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[/] [openrisc/] [trunk/] [gnu-src/] [gcc-4.5.1/] [gcc/] [cp/] [class.c] - Blame information for rev 308

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1 283 jeremybenn
/* Functions related to building classes and their related objects.
2
   Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3
   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
4
   Free Software Foundation, Inc.
5
   Contributed by Michael Tiemann (tiemann@cygnus.com)
6
 
7
This file is part of GCC.
8
 
9
GCC is free software; you can redistribute it and/or modify
10
it under the terms of the GNU General Public License as published by
11
the Free Software Foundation; either version 3, or (at your option)
12
any later version.
13
 
14
GCC is distributed in the hope that it will be useful,
15
but WITHOUT ANY WARRANTY; without even the implied warranty of
16
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17
GNU General Public License for more details.
18
 
19
You should have received a copy of the GNU General Public License
20
along with GCC; see the file COPYING3.  If not see
21
<http://www.gnu.org/licenses/>.  */
22
 
23
 
24
/* High-level class interface.  */
25
 
26
#include "config.h"
27
#include "system.h"
28
#include "coretypes.h"
29
#include "tm.h"
30
#include "tree.h"
31
#include "cp-tree.h"
32
#include "flags.h"
33
#include "rtl.h"
34
#include "output.h"
35
#include "toplev.h"
36
#include "target.h"
37
#include "convert.h"
38
#include "cgraph.h"
39
#include "tree-dump.h"
40
 
41
/* The number of nested classes being processed.  If we are not in the
42
   scope of any class, this is zero.  */
43
 
44
int current_class_depth;
45
 
46
/* In order to deal with nested classes, we keep a stack of classes.
47
   The topmost entry is the innermost class, and is the entry at index
48
   CURRENT_CLASS_DEPTH  */
49
 
50
typedef struct class_stack_node {
51
  /* The name of the class.  */
52
  tree name;
53
 
54
  /* The _TYPE node for the class.  */
55
  tree type;
56
 
57
  /* The access specifier pending for new declarations in the scope of
58
     this class.  */
59
  tree access;
60
 
61
  /* If were defining TYPE, the names used in this class.  */
62
  splay_tree names_used;
63
 
64
  /* Nonzero if this class is no longer open, because of a call to
65
     push_to_top_level.  */
66
  size_t hidden;
67
}* class_stack_node_t;
68
 
69
typedef struct vtbl_init_data_s
70
{
71
  /* The base for which we're building initializers.  */
72
  tree binfo;
73
  /* The type of the most-derived type.  */
74
  tree derived;
75
  /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76
     unless ctor_vtbl_p is true.  */
77
  tree rtti_binfo;
78
  /* The negative-index vtable initializers built up so far.  These
79
     are in order from least negative index to most negative index.  */
80
  tree inits;
81
  /* The last (i.e., most negative) entry in INITS.  */
82
  tree* last_init;
83
  /* The binfo for the virtual base for which we're building
84
     vcall offset initializers.  */
85
  tree vbase;
86
  /* The functions in vbase for which we have already provided vcall
87
     offsets.  */
88
  VEC(tree,gc) *fns;
89
  /* The vtable index of the next vcall or vbase offset.  */
90
  tree index;
91
  /* Nonzero if we are building the initializer for the primary
92
     vtable.  */
93
  int primary_vtbl_p;
94
  /* Nonzero if we are building the initializer for a construction
95
     vtable.  */
96
  int ctor_vtbl_p;
97
  /* True when adding vcall offset entries to the vtable.  False when
98
     merely computing the indices.  */
99
  bool generate_vcall_entries;
100
} vtbl_init_data;
101
 
102
/* The type of a function passed to walk_subobject_offsets.  */
103
typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
104
 
105
/* The stack itself.  This is a dynamically resized array.  The
106
   number of elements allocated is CURRENT_CLASS_STACK_SIZE.  */
107
static int current_class_stack_size;
108
static class_stack_node_t current_class_stack;
109
 
110
/* The size of the largest empty class seen in this translation unit.  */
111
static GTY (()) tree sizeof_biggest_empty_class;
112
 
113
/* An array of all local classes present in this translation unit, in
114
   declaration order.  */
115
VEC(tree,gc) *local_classes;
116
 
117
static tree get_vfield_name (tree);
118
static void finish_struct_anon (tree);
119
static tree get_vtable_name (tree);
120
static tree get_basefndecls (tree, tree);
121
static int build_primary_vtable (tree, tree);
122
static int build_secondary_vtable (tree);
123
static void finish_vtbls (tree);
124
static void modify_vtable_entry (tree, tree, tree, tree, tree *);
125
static void finish_struct_bits (tree);
126
static int alter_access (tree, tree, tree);
127
static void handle_using_decl (tree, tree);
128
static tree dfs_modify_vtables (tree, void *);
129
static tree modify_all_vtables (tree, tree);
130
static void determine_primary_bases (tree);
131
static void finish_struct_methods (tree);
132
static void maybe_warn_about_overly_private_class (tree);
133
static int method_name_cmp (const void *, const void *);
134
static int resort_method_name_cmp (const void *, const void *);
135
static void add_implicitly_declared_members (tree, int, int);
136
static tree fixed_type_or_null (tree, int *, int *);
137
static tree build_simple_base_path (tree expr, tree binfo);
138
static tree build_vtbl_ref_1 (tree, tree);
139
static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
140
static int count_fields (tree);
141
static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142
static bool check_bitfield_decl (tree);
143
static void check_field_decl (tree, tree, int *, int *, int *);
144
static void check_field_decls (tree, tree *, int *, int *);
145
static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146
static void build_base_fields (record_layout_info, splay_tree, tree *);
147
static void check_methods (tree);
148
static void remove_zero_width_bit_fields (tree);
149
static void check_bases (tree, int *, int *);
150
static void check_bases_and_members (tree);
151
static tree create_vtable_ptr (tree, tree *);
152
static void include_empty_classes (record_layout_info);
153
static void layout_class_type (tree, tree *);
154
static void propagate_binfo_offsets (tree, tree);
155
static void layout_virtual_bases (record_layout_info, splay_tree);
156
static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
157
static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
158
static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
159
static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
160
static void add_vcall_offset (tree, tree, vtbl_init_data *);
161
static void layout_vtable_decl (tree, int);
162
static tree dfs_find_final_overrider_pre (tree, void *);
163
static tree dfs_find_final_overrider_post (tree, void *);
164
static tree find_final_overrider (tree, tree, tree);
165
static int make_new_vtable (tree, tree);
166
static tree get_primary_binfo (tree);
167
static int maybe_indent_hierarchy (FILE *, int, int);
168
static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
169
static void dump_class_hierarchy (tree);
170
static void dump_class_hierarchy_1 (FILE *, int, tree);
171
static void dump_array (FILE *, tree);
172
static void dump_vtable (tree, tree, tree);
173
static void dump_vtt (tree, tree);
174
static void dump_thunk (FILE *, int, tree);
175
static tree build_vtable (tree, tree, tree);
176
static void initialize_vtable (tree, tree);
177
static void layout_nonempty_base_or_field (record_layout_info,
178
                                           tree, tree, splay_tree);
179
static tree end_of_class (tree, int);
180
static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
181
static void accumulate_vtbl_inits (tree, tree, tree, tree, tree);
182
static tree dfs_accumulate_vtbl_inits (tree, tree, tree, tree,
183
                                               tree);
184
static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
185
static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
186
static void clone_constructors_and_destructors (tree);
187
static tree build_clone (tree, tree);
188
static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
189
static void build_ctor_vtbl_group (tree, tree);
190
static void build_vtt (tree);
191
static tree binfo_ctor_vtable (tree);
192
static tree *build_vtt_inits (tree, tree, tree *, tree *);
193
static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
194
static tree dfs_fixup_binfo_vtbls (tree, void *);
195
static int record_subobject_offset (tree, tree, splay_tree);
196
static int check_subobject_offset (tree, tree, splay_tree);
197
static int walk_subobject_offsets (tree, subobject_offset_fn,
198
                                   tree, splay_tree, tree, int);
199
static void record_subobject_offsets (tree, tree, splay_tree, bool);
200
static int layout_conflict_p (tree, tree, splay_tree, int);
201
static int splay_tree_compare_integer_csts (splay_tree_key k1,
202
                                            splay_tree_key k2);
203
static void warn_about_ambiguous_bases (tree);
204
static bool type_requires_array_cookie (tree);
205
static bool contains_empty_class_p (tree);
206
static bool base_derived_from (tree, tree);
207
static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
208
static tree end_of_base (tree);
209
static tree get_vcall_index (tree, tree);
210
 
211
/* Variables shared between class.c and call.c.  */
212
 
213
#ifdef GATHER_STATISTICS
214
int n_vtables = 0;
215
int n_vtable_entries = 0;
216
int n_vtable_searches = 0;
217
int n_vtable_elems = 0;
218
int n_convert_harshness = 0;
219
int n_compute_conversion_costs = 0;
220
int n_inner_fields_searched = 0;
221
#endif
222
 
223
/* Convert to or from a base subobject.  EXPR is an expression of type
224
   `A' or `A*', an expression of type `B' or `B*' is returned.  To
225
   convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
226
   the B base instance within A.  To convert base A to derived B, CODE
227
   is MINUS_EXPR and BINFO is the binfo for the A instance within B.
228
   In this latter case, A must not be a morally virtual base of B.
229
   NONNULL is true if EXPR is known to be non-NULL (this is only
230
   needed when EXPR is of pointer type).  CV qualifiers are preserved
231
   from EXPR.  */
232
 
233
tree
234
build_base_path (enum tree_code code,
235
                 tree expr,
236
                 tree binfo,
237
                 int nonnull)
238
{
239
  tree v_binfo = NULL_TREE;
240
  tree d_binfo = NULL_TREE;
241
  tree probe;
242
  tree offset;
243
  tree target_type;
244
  tree null_test = NULL;
245
  tree ptr_target_type;
246
  int fixed_type_p;
247
  int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
248
  bool has_empty = false;
249
  bool virtual_access;
250
 
251
  if (expr == error_mark_node || binfo == error_mark_node || !binfo)
252
    return error_mark_node;
253
 
254
  for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
255
    {
256
      d_binfo = probe;
257
      if (is_empty_class (BINFO_TYPE (probe)))
258
        has_empty = true;
259
      if (!v_binfo && BINFO_VIRTUAL_P (probe))
260
        v_binfo = probe;
261
    }
262
 
263
  probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
264
  if (want_pointer)
265
    probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
266
 
267
  gcc_assert ((code == MINUS_EXPR
268
               && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
269
              || (code == PLUS_EXPR
270
                  && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
271
 
272
  if (binfo == d_binfo)
273
    /* Nothing to do.  */
274
    return expr;
275
 
276
  if (code == MINUS_EXPR && v_binfo)
277
    {
278
      error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
279
             BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
280
      return error_mark_node;
281
    }
282
 
283
  if (!want_pointer)
284
    /* This must happen before the call to save_expr.  */
285
    expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
286
 
287
  offset = BINFO_OFFSET (binfo);
288
  fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
289
  target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
290
 
291
  /* Do we need to look in the vtable for the real offset?  */
292
  virtual_access = (v_binfo && fixed_type_p <= 0);
293
 
294
  /* Don't bother with the calculations inside sizeof; they'll ICE if the
295
     source type is incomplete and the pointer value doesn't matter.  */
296
  if (cp_unevaluated_operand != 0)
297
    {
298
      expr = build_nop (build_pointer_type (target_type), expr);
299
      if (!want_pointer)
300
        expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
301
      return expr;
302
    }
303
 
304
  /* Do we need to check for a null pointer?  */
305
  if (want_pointer && !nonnull)
306
    {
307
      /* If we know the conversion will not actually change the value
308
         of EXPR, then we can avoid testing the expression for NULL.
309
         We have to avoid generating a COMPONENT_REF for a base class
310
         field, because other parts of the compiler know that such
311
         expressions are always non-NULL.  */
312
      if (!virtual_access && integer_zerop (offset))
313
        {
314
          tree class_type;
315
          /* TARGET_TYPE has been extracted from BINFO, and, is
316
             therefore always cv-unqualified.  Extract the
317
             cv-qualifiers from EXPR so that the expression returned
318
             matches the input.  */
319
          class_type = TREE_TYPE (TREE_TYPE (expr));
320
          target_type
321
            = cp_build_qualified_type (target_type,
322
                                       cp_type_quals (class_type));
323
          return build_nop (build_pointer_type (target_type), expr);
324
        }
325
      null_test = error_mark_node;
326
    }
327
 
328
  /* Protect against multiple evaluation if necessary.  */
329
  if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
330
    expr = save_expr (expr);
331
 
332
  /* Now that we've saved expr, build the real null test.  */
333
  if (null_test)
334
    {
335
      tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
336
      null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
337
                               expr, zero);
338
    }
339
 
340
  /* If this is a simple base reference, express it as a COMPONENT_REF.  */
341
  if (code == PLUS_EXPR && !virtual_access
342
      /* We don't build base fields for empty bases, and they aren't very
343
         interesting to the optimizers anyway.  */
344
      && !has_empty)
345
    {
346
      expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
347
      expr = build_simple_base_path (expr, binfo);
348
      if (want_pointer)
349
        expr = build_address (expr);
350
      target_type = TREE_TYPE (expr);
351
      goto out;
352
    }
353
 
354
  if (virtual_access)
355
    {
356
      /* Going via virtual base V_BINFO.  We need the static offset
357
         from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
358
         V_BINFO.  That offset is an entry in D_BINFO's vtable.  */
359
      tree v_offset;
360
 
361
      if (fixed_type_p < 0 && in_base_initializer)
362
        {
363
          /* In a base member initializer, we cannot rely on the
364
             vtable being set up.  We have to indirect via the
365
             vtt_parm.  */
366
          tree t;
367
 
368
          t = TREE_TYPE (TYPE_VFIELD (current_class_type));
369
          t = build_pointer_type (t);
370
          v_offset = convert (t, current_vtt_parm);
371
          v_offset = cp_build_indirect_ref (v_offset, RO_NULL,
372
                                            tf_warning_or_error);
373
        }
374
      else
375
        v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
376
                                                            tf_warning_or_error),
377
                                     TREE_TYPE (TREE_TYPE (expr)));
378
 
379
      v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
380
                         v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
381
      v_offset = build1 (NOP_EXPR,
382
                         build_pointer_type (ptrdiff_type_node),
383
                         v_offset);
384
      v_offset = cp_build_indirect_ref (v_offset, RO_NULL, tf_warning_or_error);
385
      TREE_CONSTANT (v_offset) = 1;
386
 
387
      offset = convert_to_integer (ptrdiff_type_node,
388
                                   size_diffop_loc (input_location, offset,
389
                                                BINFO_OFFSET (v_binfo)));
390
 
391
      if (!integer_zerop (offset))
392
        v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
393
 
394
      if (fixed_type_p < 0)
395
        /* Negative fixed_type_p means this is a constructor or destructor;
396
           virtual base layout is fixed in in-charge [cd]tors, but not in
397
           base [cd]tors.  */
398
        offset = build3 (COND_EXPR, ptrdiff_type_node,
399
                         build2 (EQ_EXPR, boolean_type_node,
400
                                 current_in_charge_parm, integer_zero_node),
401
                         v_offset,
402
                         convert_to_integer (ptrdiff_type_node,
403
                                             BINFO_OFFSET (binfo)));
404
      else
405
        offset = v_offset;
406
    }
407
 
408
  target_type = cp_build_qualified_type
409
    (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
410
  ptr_target_type = build_pointer_type (target_type);
411
  if (want_pointer)
412
    target_type = ptr_target_type;
413
 
414
  expr = build1 (NOP_EXPR, ptr_target_type, expr);
415
 
416
  if (!integer_zerop (offset))
417
    {
418
      offset = fold_convert (sizetype, offset);
419
      if (code == MINUS_EXPR)
420
        offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
421
      expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
422
    }
423
  else
424
    null_test = NULL;
425
 
426
  if (!want_pointer)
427
    expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
428
 
429
 out:
430
  if (null_test)
431
    expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
432
                        fold_build1_loc (input_location, NOP_EXPR, target_type,
433
                                     integer_zero_node));
434
 
435
  return expr;
436
}
437
 
438
/* Subroutine of build_base_path; EXPR and BINFO are as in that function.
439
   Perform a derived-to-base conversion by recursively building up a
440
   sequence of COMPONENT_REFs to the appropriate base fields.  */
441
 
442
static tree
443
build_simple_base_path (tree expr, tree binfo)
444
{
445
  tree type = BINFO_TYPE (binfo);
446
  tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
447
  tree field;
448
 
449
  if (d_binfo == NULL_TREE)
450
    {
451
      tree temp;
452
 
453
      gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
454
 
455
      /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
456
         into `(*(a ?  &b : &c)).x', and so on.  A COND_EXPR is only
457
         an lvalue in the front end; only _DECLs and _REFs are lvalues
458
         in the back end.  */
459
      temp = unary_complex_lvalue (ADDR_EXPR, expr);
460
      if (temp)
461
        expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
462
 
463
      return expr;
464
    }
465
 
466
  /* Recurse.  */
467
  expr = build_simple_base_path (expr, d_binfo);
468
 
469
  for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
470
       field; field = TREE_CHAIN (field))
471
    /* Is this the base field created by build_base_field?  */
472
    if (TREE_CODE (field) == FIELD_DECL
473
        && DECL_FIELD_IS_BASE (field)
474
        && TREE_TYPE (field) == type)
475
      {
476
        /* We don't use build_class_member_access_expr here, as that
477
           has unnecessary checks, and more importantly results in
478
           recursive calls to dfs_walk_once.  */
479
        int type_quals = cp_type_quals (TREE_TYPE (expr));
480
 
481
        expr = build3 (COMPONENT_REF,
482
                       cp_build_qualified_type (type, type_quals),
483
                       expr, field, NULL_TREE);
484
        expr = fold_if_not_in_template (expr);
485
 
486
        /* Mark the expression const or volatile, as appropriate.
487
           Even though we've dealt with the type above, we still have
488
           to mark the expression itself.  */
489
        if (type_quals & TYPE_QUAL_CONST)
490
          TREE_READONLY (expr) = 1;
491
        if (type_quals & TYPE_QUAL_VOLATILE)
492
          TREE_THIS_VOLATILE (expr) = 1;
493
 
494
        return expr;
495
      }
496
 
497
  /* Didn't find the base field?!?  */
498
  gcc_unreachable ();
499
}
500
 
501
/* Convert OBJECT to the base TYPE.  OBJECT is an expression whose
502
   type is a class type or a pointer to a class type.  In the former
503
   case, TYPE is also a class type; in the latter it is another
504
   pointer type.  If CHECK_ACCESS is true, an error message is emitted
505
   if TYPE is inaccessible.  If OBJECT has pointer type, the value is
506
   assumed to be non-NULL.  */
507
 
508
tree
509
convert_to_base (tree object, tree type, bool check_access, bool nonnull)
510
{
511
  tree binfo;
512
  tree object_type;
513
 
514
  if (TYPE_PTR_P (TREE_TYPE (object)))
515
    {
516
      object_type = TREE_TYPE (TREE_TYPE (object));
517
      type = TREE_TYPE (type);
518
    }
519
  else
520
    object_type = TREE_TYPE (object);
521
 
522
  binfo = lookup_base (object_type, type,
523
                       check_access ? ba_check : ba_unique,
524
                       NULL);
525
  if (!binfo || binfo == error_mark_node)
526
    return error_mark_node;
527
 
528
  return build_base_path (PLUS_EXPR, object, binfo, nonnull);
529
}
530
 
531
/* EXPR is an expression with unqualified class type.  BASE is a base
532
   binfo of that class type.  Returns EXPR, converted to the BASE
533
   type.  This function assumes that EXPR is the most derived class;
534
   therefore virtual bases can be found at their static offsets.  */
535
 
536
tree
537
convert_to_base_statically (tree expr, tree base)
538
{
539
  tree expr_type;
540
 
541
  expr_type = TREE_TYPE (expr);
542
  if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
543
    {
544
      tree pointer_type;
545
 
546
      pointer_type = build_pointer_type (expr_type);
547
 
548
      /* We use fold_build2 and fold_convert below to simplify the trees
549
         provided to the optimizers.  It is not safe to call these functions
550
         when processing a template because they do not handle C++-specific
551
         trees.  */
552
      gcc_assert (!processing_template_decl);
553
      expr = cp_build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1,
554
                             tf_warning_or_error);
555
      if (!integer_zerop (BINFO_OFFSET (base)))
556
        expr = fold_build2_loc (input_location,
557
                            POINTER_PLUS_EXPR, pointer_type, expr,
558
                            fold_convert (sizetype, BINFO_OFFSET (base)));
559
      expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
560
      expr = build_fold_indirect_ref_loc (input_location, expr);
561
    }
562
 
563
  return expr;
564
}
565
 
566
 
567
tree
568
build_vfield_ref (tree datum, tree type)
569
{
570
  tree vfield, vcontext;
571
 
572
  if (datum == error_mark_node)
573
    return error_mark_node;
574
 
575
  /* First, convert to the requested type.  */
576
  if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
577
    datum = convert_to_base (datum, type, /*check_access=*/false,
578
                             /*nonnull=*/true);
579
 
580
  /* Second, the requested type may not be the owner of its own vptr.
581
     If not, convert to the base class that owns it.  We cannot use
582
     convert_to_base here, because VCONTEXT may appear more than once
583
     in the inheritance hierarchy of TYPE, and thus direct conversion
584
     between the types may be ambiguous.  Following the path back up
585
     one step at a time via primary bases avoids the problem.  */
586
  vfield = TYPE_VFIELD (type);
587
  vcontext = DECL_CONTEXT (vfield);
588
  while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
589
    {
590
      datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
591
      type = TREE_TYPE (datum);
592
    }
593
 
594
  return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
595
}
596
 
597
/* Given an object INSTANCE, return an expression which yields the
598
   vtable element corresponding to INDEX.  There are many special
599
   cases for INSTANCE which we take care of here, mainly to avoid
600
   creating extra tree nodes when we don't have to.  */
601
 
602
static tree
603
build_vtbl_ref_1 (tree instance, tree idx)
604
{
605
  tree aref;
606
  tree vtbl = NULL_TREE;
607
 
608
  /* Try to figure out what a reference refers to, and
609
     access its virtual function table directly.  */
610
 
611
  int cdtorp = 0;
612
  tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
613
 
614
  tree basetype = non_reference (TREE_TYPE (instance));
615
 
616
  if (fixed_type && !cdtorp)
617
    {
618
      tree binfo = lookup_base (fixed_type, basetype,
619
                                ba_unique | ba_quiet, NULL);
620
      if (binfo)
621
        vtbl = unshare_expr (BINFO_VTABLE (binfo));
622
    }
623
 
624
  if (!vtbl)
625
    vtbl = build_vfield_ref (instance, basetype);
626
 
627
  aref = build_array_ref (input_location, vtbl, idx);
628
  TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
629
 
630
  return aref;
631
}
632
 
633
tree
634
build_vtbl_ref (tree instance, tree idx)
635
{
636
  tree aref = build_vtbl_ref_1 (instance, idx);
637
 
638
  return aref;
639
}
640
 
641
/* Given a stable object pointer INSTANCE_PTR, return an expression which
642
   yields a function pointer corresponding to vtable element INDEX.  */
643
 
644
tree
645
build_vfn_ref (tree instance_ptr, tree idx)
646
{
647
  tree aref;
648
 
649
  aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
650
                                                  tf_warning_or_error),
651
                           idx);
652
 
653
  /* When using function descriptors, the address of the
654
     vtable entry is treated as a function pointer.  */
655
  if (TARGET_VTABLE_USES_DESCRIPTORS)
656
    aref = build1 (NOP_EXPR, TREE_TYPE (aref),
657
                   cp_build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1,
658
                                   tf_warning_or_error));
659
 
660
  /* Remember this as a method reference, for later devirtualization.  */
661
  aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
662
 
663
  return aref;
664
}
665
 
666
/* Return the name of the virtual function table (as an IDENTIFIER_NODE)
667
   for the given TYPE.  */
668
 
669
static tree
670
get_vtable_name (tree type)
671
{
672
  return mangle_vtbl_for_type (type);
673
}
674
 
675
/* DECL is an entity associated with TYPE, like a virtual table or an
676
   implicitly generated constructor.  Determine whether or not DECL
677
   should have external or internal linkage at the object file
678
   level.  This routine does not deal with COMDAT linkage and other
679
   similar complexities; it simply sets TREE_PUBLIC if it possible for
680
   entities in other translation units to contain copies of DECL, in
681
   the abstract.  */
682
 
683
void
684
set_linkage_according_to_type (tree type, tree decl)
685
{
686
  /* If TYPE involves a local class in a function with internal
687
     linkage, then DECL should have internal linkage too.  Other local
688
     classes have no linkage -- but if their containing functions
689
     have external linkage, it makes sense for DECL to have external
690
     linkage too.  That will allow template definitions to be merged,
691
     for example.  */
692
  if (no_linkage_check (type, /*relaxed_p=*/true))
693
    {
694
      TREE_PUBLIC (decl) = 0;
695
      DECL_INTERFACE_KNOWN (decl) = 1;
696
    }
697
  else
698
    TREE_PUBLIC (decl) = 1;
699
}
700
 
701
/* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
702
   (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
703
   Use NAME for the name of the vtable, and VTABLE_TYPE for its type.  */
704
 
705
static tree
706
build_vtable (tree class_type, tree name, tree vtable_type)
707
{
708
  tree decl;
709
 
710
  decl = build_lang_decl (VAR_DECL, name, vtable_type);
711
  /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
712
     now to avoid confusion in mangle_decl.  */
713
  SET_DECL_ASSEMBLER_NAME (decl, name);
714
  DECL_CONTEXT (decl) = class_type;
715
  DECL_ARTIFICIAL (decl) = 1;
716
  TREE_STATIC (decl) = 1;
717
  TREE_READONLY (decl) = 1;
718
  DECL_VIRTUAL_P (decl) = 1;
719
  DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
720
  DECL_VTABLE_OR_VTT_P (decl) = 1;
721
  /* At one time the vtable info was grabbed 2 words at a time.  This
722
     fails on sparc unless you have 8-byte alignment.  (tiemann) */
723
  DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
724
                           DECL_ALIGN (decl));
725
  set_linkage_according_to_type (class_type, decl);
726
  /* The vtable has not been defined -- yet.  */
727
  DECL_EXTERNAL (decl) = 1;
728
  DECL_NOT_REALLY_EXTERN (decl) = 1;
729
 
730
  /* Mark the VAR_DECL node representing the vtable itself as a
731
     "gratuitous" one, thereby forcing dwarfout.c to ignore it.  It
732
     is rather important that such things be ignored because any
733
     effort to actually generate DWARF for them will run into
734
     trouble when/if we encounter code like:
735
 
736
     #pragma interface
737
     struct S { virtual void member (); };
738
 
739
     because the artificial declaration of the vtable itself (as
740
     manufactured by the g++ front end) will say that the vtable is
741
     a static member of `S' but only *after* the debug output for
742
     the definition of `S' has already been output.  This causes
743
     grief because the DWARF entry for the definition of the vtable
744
     will try to refer back to an earlier *declaration* of the
745
     vtable as a static member of `S' and there won't be one.  We
746
     might be able to arrange to have the "vtable static member"
747
     attached to the member list for `S' before the debug info for
748
     `S' get written (which would solve the problem) but that would
749
     require more intrusive changes to the g++ front end.  */
750
  DECL_IGNORED_P (decl) = 1;
751
 
752
  return decl;
753
}
754
 
755
/* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
756
   or even complete.  If this does not exist, create it.  If COMPLETE is
757
   nonzero, then complete the definition of it -- that will render it
758
   impossible to actually build the vtable, but is useful to get at those
759
   which are known to exist in the runtime.  */
760
 
761
tree
762
get_vtable_decl (tree type, int complete)
763
{
764
  tree decl;
765
 
766
  if (CLASSTYPE_VTABLES (type))
767
    return CLASSTYPE_VTABLES (type);
768
 
769
  decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
770
  CLASSTYPE_VTABLES (type) = decl;
771
 
772
  if (complete)
773
    {
774
      DECL_EXTERNAL (decl) = 1;
775
      cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
776
    }
777
 
778
  return decl;
779
}
780
 
781
/* Build the primary virtual function table for TYPE.  If BINFO is
782
   non-NULL, build the vtable starting with the initial approximation
783
   that it is the same as the one which is the head of the association
784
   list.  Returns a nonzero value if a new vtable is actually
785
   created.  */
786
 
787
static int
788
build_primary_vtable (tree binfo, tree type)
789
{
790
  tree decl;
791
  tree virtuals;
792
 
793
  decl = get_vtable_decl (type, /*complete=*/0);
794
 
795
  if (binfo)
796
    {
797
      if (BINFO_NEW_VTABLE_MARKED (binfo))
798
        /* We have already created a vtable for this base, so there's
799
           no need to do it again.  */
800
        return 0;
801
 
802
      virtuals = copy_list (BINFO_VIRTUALS (binfo));
803
      TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
804
      DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
805
      DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
806
    }
807
  else
808
    {
809
      gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
810
      virtuals = NULL_TREE;
811
    }
812
 
813
#ifdef GATHER_STATISTICS
814
  n_vtables += 1;
815
  n_vtable_elems += list_length (virtuals);
816
#endif
817
 
818
  /* Initialize the association list for this type, based
819
     on our first approximation.  */
820
  BINFO_VTABLE (TYPE_BINFO (type)) = decl;
821
  BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
822
  SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
823
  return 1;
824
}
825
 
826
/* Give BINFO a new virtual function table which is initialized
827
   with a skeleton-copy of its original initialization.  The only
828
   entry that changes is the `delta' entry, so we can really
829
   share a lot of structure.
830
 
831
   FOR_TYPE is the most derived type which caused this table to
832
   be needed.
833
 
834
   Returns nonzero if we haven't met BINFO before.
835
 
836
   The order in which vtables are built (by calling this function) for
837
   an object must remain the same, otherwise a binary incompatibility
838
   can result.  */
839
 
840
static int
841
build_secondary_vtable (tree binfo)
842
{
843
  if (BINFO_NEW_VTABLE_MARKED (binfo))
844
    /* We already created a vtable for this base.  There's no need to
845
       do it again.  */
846
    return 0;
847
 
848
  /* Remember that we've created a vtable for this BINFO, so that we
849
     don't try to do so again.  */
850
  SET_BINFO_NEW_VTABLE_MARKED (binfo);
851
 
852
  /* Make fresh virtual list, so we can smash it later.  */
853
  BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
854
 
855
  /* Secondary vtables are laid out as part of the same structure as
856
     the primary vtable.  */
857
  BINFO_VTABLE (binfo) = NULL_TREE;
858
  return 1;
859
}
860
 
861
/* Create a new vtable for BINFO which is the hierarchy dominated by
862
   T. Return nonzero if we actually created a new vtable.  */
863
 
864
static int
865
make_new_vtable (tree t, tree binfo)
866
{
867
  if (binfo == TYPE_BINFO (t))
868
    /* In this case, it is *type*'s vtable we are modifying.  We start
869
       with the approximation that its vtable is that of the
870
       immediate base class.  */
871
    return build_primary_vtable (binfo, t);
872
  else
873
    /* This is our very own copy of `basetype' to play with.  Later,
874
       we will fill in all the virtual functions that override the
875
       virtual functions in these base classes which are not defined
876
       by the current type.  */
877
    return build_secondary_vtable (binfo);
878
}
879
 
880
/* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
881
   (which is in the hierarchy dominated by T) list FNDECL as its
882
   BV_FN.  DELTA is the required constant adjustment from the `this'
883
   pointer where the vtable entry appears to the `this' required when
884
   the function is actually called.  */
885
 
886
static void
887
modify_vtable_entry (tree t,
888
                     tree binfo,
889
                     tree fndecl,
890
                     tree delta,
891
                     tree *virtuals)
892
{
893
  tree v;
894
 
895
  v = *virtuals;
896
 
897
  if (fndecl != BV_FN (v)
898
      || !tree_int_cst_equal (delta, BV_DELTA (v)))
899
    {
900
      /* We need a new vtable for BINFO.  */
901
      if (make_new_vtable (t, binfo))
902
        {
903
          /* If we really did make a new vtable, we also made a copy
904
             of the BINFO_VIRTUALS list.  Now, we have to find the
905
             corresponding entry in that list.  */
906
          *virtuals = BINFO_VIRTUALS (binfo);
907
          while (BV_FN (*virtuals) != BV_FN (v))
908
            *virtuals = TREE_CHAIN (*virtuals);
909
          v = *virtuals;
910
        }
911
 
912
      BV_DELTA (v) = delta;
913
      BV_VCALL_INDEX (v) = NULL_TREE;
914
      BV_FN (v) = fndecl;
915
    }
916
}
917
 
918
 
919
/* Add method METHOD to class TYPE.  If USING_DECL is non-null, it is
920
   the USING_DECL naming METHOD.  Returns true if the method could be
921
   added to the method vec.  */
922
 
923
bool
924
add_method (tree type, tree method, tree using_decl)
925
{
926
  unsigned slot;
927
  tree overload;
928
  bool template_conv_p = false;
929
  bool conv_p;
930
  VEC(tree,gc) *method_vec;
931
  bool complete_p;
932
  bool insert_p = false;
933
  tree current_fns;
934
  tree fns;
935
 
936
  if (method == error_mark_node)
937
    return false;
938
 
939
  complete_p = COMPLETE_TYPE_P (type);
940
  conv_p = DECL_CONV_FN_P (method);
941
  if (conv_p)
942
    template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
943
                       && DECL_TEMPLATE_CONV_FN_P (method));
944
 
945
  method_vec = CLASSTYPE_METHOD_VEC (type);
946
  if (!method_vec)
947
    {
948
      /* Make a new method vector.  We start with 8 entries.  We must
949
         allocate at least two (for constructors and destructors), and
950
         we're going to end up with an assignment operator at some
951
         point as well.  */
952
      method_vec = VEC_alloc (tree, gc, 8);
953
      /* Create slots for constructors and destructors.  */
954
      VEC_quick_push (tree, method_vec, NULL_TREE);
955
      VEC_quick_push (tree, method_vec, NULL_TREE);
956
      CLASSTYPE_METHOD_VEC (type) = method_vec;
957
    }
958
 
959
  /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc.  */
960
  grok_special_member_properties (method);
961
 
962
  /* Constructors and destructors go in special slots.  */
963
  if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
964
    slot = CLASSTYPE_CONSTRUCTOR_SLOT;
965
  else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
966
    {
967
      slot = CLASSTYPE_DESTRUCTOR_SLOT;
968
 
969
      if (TYPE_FOR_JAVA (type))
970
        {
971
          if (!DECL_ARTIFICIAL (method))
972
            error ("Java class %qT cannot have a destructor", type);
973
          else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
974
            error ("Java class %qT cannot have an implicit non-trivial "
975
                   "destructor",
976
                   type);
977
        }
978
    }
979
  else
980
    {
981
      tree m;
982
 
983
      insert_p = true;
984
      /* See if we already have an entry with this name.  */
985
      for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
986
           VEC_iterate (tree, method_vec, slot, m);
987
           ++slot)
988
        {
989
          m = OVL_CURRENT (m);
990
          if (template_conv_p)
991
            {
992
              if (TREE_CODE (m) == TEMPLATE_DECL
993
                  && DECL_TEMPLATE_CONV_FN_P (m))
994
                insert_p = false;
995
              break;
996
            }
997
          if (conv_p && !DECL_CONV_FN_P (m))
998
            break;
999
          if (DECL_NAME (m) == DECL_NAME (method))
1000
            {
1001
              insert_p = false;
1002
              break;
1003
            }
1004
          if (complete_p
1005
              && !DECL_CONV_FN_P (m)
1006
              && DECL_NAME (m) > DECL_NAME (method))
1007
            break;
1008
        }
1009
    }
1010
  current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1011
 
1012
  /* Check to see if we've already got this method.  */
1013
  for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1014
    {
1015
      tree fn = OVL_CURRENT (fns);
1016
      tree fn_type;
1017
      tree method_type;
1018
      tree parms1;
1019
      tree parms2;
1020
 
1021
      if (TREE_CODE (fn) != TREE_CODE (method))
1022
        continue;
1023
 
1024
      /* [over.load] Member function declarations with the
1025
         same name and the same parameter types cannot be
1026
         overloaded if any of them is a static member
1027
         function declaration.
1028
 
1029
         [namespace.udecl] When a using-declaration brings names
1030
         from a base class into a derived class scope, member
1031
         functions in the derived class override and/or hide member
1032
         functions with the same name and parameter types in a base
1033
         class (rather than conflicting).  */
1034
      fn_type = TREE_TYPE (fn);
1035
      method_type = TREE_TYPE (method);
1036
      parms1 = TYPE_ARG_TYPES (fn_type);
1037
      parms2 = TYPE_ARG_TYPES (method_type);
1038
 
1039
      /* Compare the quals on the 'this' parm.  Don't compare
1040
         the whole types, as used functions are treated as
1041
         coming from the using class in overload resolution.  */
1042
      if (! DECL_STATIC_FUNCTION_P (fn)
1043
          && ! DECL_STATIC_FUNCTION_P (method)
1044
          && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1045
          && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1046
          && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1047
              != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1048
        continue;
1049
 
1050
      /* For templates, the return type and template parameters
1051
         must be identical.  */
1052
      if (TREE_CODE (fn) == TEMPLATE_DECL
1053
          && (!same_type_p (TREE_TYPE (fn_type),
1054
                            TREE_TYPE (method_type))
1055
              || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1056
                                       DECL_TEMPLATE_PARMS (method))))
1057
        continue;
1058
 
1059
      if (! DECL_STATIC_FUNCTION_P (fn))
1060
        parms1 = TREE_CHAIN (parms1);
1061
      if (! DECL_STATIC_FUNCTION_P (method))
1062
        parms2 = TREE_CHAIN (parms2);
1063
 
1064
      if (compparms (parms1, parms2)
1065
          && (!DECL_CONV_FN_P (fn)
1066
              || same_type_p (TREE_TYPE (fn_type),
1067
                              TREE_TYPE (method_type))))
1068
        {
1069
          if (using_decl)
1070
            {
1071
              if (DECL_CONTEXT (fn) == type)
1072
                /* Defer to the local function.  */
1073
                return false;
1074
              if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1075
                error ("repeated using declaration %q+D", using_decl);
1076
              else
1077
                error ("using declaration %q+D conflicts with a previous using declaration",
1078
                       using_decl);
1079
            }
1080
          else
1081
            {
1082
              error ("%q+#D cannot be overloaded", method);
1083
              error ("with %q+#D", fn);
1084
            }
1085
 
1086
          /* We don't call duplicate_decls here to merge the
1087
             declarations because that will confuse things if the
1088
             methods have inline definitions.  In particular, we
1089
             will crash while processing the definitions.  */
1090
          return false;
1091
        }
1092
    }
1093
 
1094
  /* A class should never have more than one destructor.  */
1095
  if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1096
    return false;
1097
 
1098
  /* Add the new binding.  */
1099
  overload = build_overload (method, current_fns);
1100
 
1101
  if (conv_p)
1102
    TYPE_HAS_CONVERSION (type) = 1;
1103
  else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1104
    push_class_level_binding (DECL_NAME (method), overload);
1105
 
1106
  if (insert_p)
1107
    {
1108
      bool reallocated;
1109
 
1110
      /* We only expect to add few methods in the COMPLETE_P case, so
1111
         just make room for one more method in that case.  */
1112
      if (complete_p)
1113
        reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1114
      else
1115
        reallocated = VEC_reserve (tree, gc, method_vec, 1);
1116
      if (reallocated)
1117
        CLASSTYPE_METHOD_VEC (type) = method_vec;
1118
      if (slot == VEC_length (tree, method_vec))
1119
        VEC_quick_push (tree, method_vec, overload);
1120
      else
1121
        VEC_quick_insert (tree, method_vec, slot, overload);
1122
    }
1123
  else
1124
    /* Replace the current slot.  */
1125
    VEC_replace (tree, method_vec, slot, overload);
1126
  return true;
1127
}
1128
 
1129
/* Subroutines of finish_struct.  */
1130
 
1131
/* Change the access of FDECL to ACCESS in T.  Return 1 if change was
1132
   legit, otherwise return 0.  */
1133
 
1134
static int
1135
alter_access (tree t, tree fdecl, tree access)
1136
{
1137
  tree elem;
1138
 
1139
  if (!DECL_LANG_SPECIFIC (fdecl))
1140
    retrofit_lang_decl (fdecl);
1141
 
1142
  gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1143
 
1144
  elem = purpose_member (t, DECL_ACCESS (fdecl));
1145
  if (elem)
1146
    {
1147
      if (TREE_VALUE (elem) != access)
1148
        {
1149
          if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1150
            error ("conflicting access specifications for method"
1151
                   " %q+D, ignored", TREE_TYPE (fdecl));
1152
          else
1153
            error ("conflicting access specifications for field %qE, ignored",
1154
                   DECL_NAME (fdecl));
1155
        }
1156
      else
1157
        {
1158
          /* They're changing the access to the same thing they changed
1159
             it to before.  That's OK.  */
1160
          ;
1161
        }
1162
    }
1163
  else
1164
    {
1165
      perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1166
      DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1167
      return 1;
1168
    }
1169
  return 0;
1170
}
1171
 
1172
/* Process the USING_DECL, which is a member of T.  */
1173
 
1174
static void
1175
handle_using_decl (tree using_decl, tree t)
1176
{
1177
  tree decl = USING_DECL_DECLS (using_decl);
1178
  tree name = DECL_NAME (using_decl);
1179
  tree access
1180
    = TREE_PRIVATE (using_decl) ? access_private_node
1181
    : TREE_PROTECTED (using_decl) ? access_protected_node
1182
    : access_public_node;
1183
  tree flist = NULL_TREE;
1184
  tree old_value;
1185
 
1186
  gcc_assert (!processing_template_decl && decl);
1187
 
1188
  old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1189
  if (old_value)
1190
    {
1191
      if (is_overloaded_fn (old_value))
1192
        old_value = OVL_CURRENT (old_value);
1193
 
1194
      if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1195
        /* OK */;
1196
      else
1197
        old_value = NULL_TREE;
1198
    }
1199
 
1200
  cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1201
 
1202
  if (is_overloaded_fn (decl))
1203
    flist = decl;
1204
 
1205
  if (! old_value)
1206
    ;
1207
  else if (is_overloaded_fn (old_value))
1208
    {
1209
      if (flist)
1210
        /* It's OK to use functions from a base when there are functions with
1211
           the same name already present in the current class.  */;
1212
      else
1213
        {
1214
          error ("%q+D invalid in %q#T", using_decl, t);
1215
          error ("  because of local method %q+#D with same name",
1216
                 OVL_CURRENT (old_value));
1217
          return;
1218
        }
1219
    }
1220
  else if (!DECL_ARTIFICIAL (old_value))
1221
    {
1222
      error ("%q+D invalid in %q#T", using_decl, t);
1223
      error ("  because of local member %q+#D with same name", old_value);
1224
      return;
1225
    }
1226
 
1227
  /* Make type T see field decl FDECL with access ACCESS.  */
1228
  if (flist)
1229
    for (; flist; flist = OVL_NEXT (flist))
1230
      {
1231
        add_method (t, OVL_CURRENT (flist), using_decl);
1232
        alter_access (t, OVL_CURRENT (flist), access);
1233
      }
1234
  else
1235
    alter_access (t, decl, access);
1236
}
1237
 
1238
/* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1239
   and NO_CONST_ASN_REF_P.  Also set flag bits in T based on
1240
   properties of the bases.  */
1241
 
1242
static void
1243
check_bases (tree t,
1244
             int* cant_have_const_ctor_p,
1245
             int* no_const_asn_ref_p)
1246
{
1247
  int i;
1248
  int seen_non_virtual_nearly_empty_base_p;
1249
  tree base_binfo;
1250
  tree binfo;
1251
  tree field = NULL_TREE;
1252
 
1253
  seen_non_virtual_nearly_empty_base_p = 0;
1254
 
1255
  if (!CLASSTYPE_NON_STD_LAYOUT (t))
1256
    for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1257
      if (TREE_CODE (field) == FIELD_DECL)
1258
        break;
1259
 
1260
  for (binfo = TYPE_BINFO (t), i = 0;
1261
       BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1262
    {
1263
      tree basetype = TREE_TYPE (base_binfo);
1264
 
1265
      gcc_assert (COMPLETE_TYPE_P (basetype));
1266
 
1267
      /* Effective C++ rule 14.  We only need to check TYPE_POLYMORPHIC_P
1268
         here because the case of virtual functions but non-virtual
1269
         dtor is handled in finish_struct_1.  */
1270
      if (!TYPE_POLYMORPHIC_P (basetype))
1271
        warning (OPT_Weffc__,
1272
                 "base class %q#T has a non-virtual destructor", basetype);
1273
 
1274
      /* If the base class doesn't have copy constructors or
1275
         assignment operators that take const references, then the
1276
         derived class cannot have such a member automatically
1277
         generated.  */
1278
      if (! TYPE_HAS_CONST_INIT_REF (basetype))
1279
        *cant_have_const_ctor_p = 1;
1280
      if (TYPE_HAS_ASSIGN_REF (basetype)
1281
          && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1282
        *no_const_asn_ref_p = 1;
1283
 
1284
      if (BINFO_VIRTUAL_P (base_binfo))
1285
        /* A virtual base does not effect nearly emptiness.  */
1286
        ;
1287
      else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1288
        {
1289
          if (seen_non_virtual_nearly_empty_base_p)
1290
            /* And if there is more than one nearly empty base, then the
1291
               derived class is not nearly empty either.  */
1292
            CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1293
          else
1294
            /* Remember we've seen one.  */
1295
            seen_non_virtual_nearly_empty_base_p = 1;
1296
        }
1297
      else if (!is_empty_class (basetype))
1298
        /* If the base class is not empty or nearly empty, then this
1299
           class cannot be nearly empty.  */
1300
        CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1301
 
1302
      /* A lot of properties from the bases also apply to the derived
1303
         class.  */
1304
      TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1305
      TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1306
        |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1307
      TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1308
        |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1309
      TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1310
      TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1311
      CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1312
        |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1313
      TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1314
 
1315
      /*  A standard-layout class is a class that:
1316
          ...
1317
          * has no non-standard-layout base classes,  */
1318
      CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1319
      if (!CLASSTYPE_NON_STD_LAYOUT (t))
1320
        {
1321
          tree basefield;
1322
          /* ...has no base classes of the same type as the first non-static
1323
             data member...  */
1324
          if (field && DECL_CONTEXT (field) == t
1325
              && (same_type_ignoring_top_level_qualifiers_p
1326
                  (TREE_TYPE (field), basetype)))
1327
            CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1328
          else
1329
            /* ...either has no non-static data members in the most-derived
1330
               class and at most one base class with non-static data
1331
               members, or has no base classes with non-static data
1332
               members */
1333
            for (basefield = TYPE_FIELDS (basetype); basefield;
1334
                 basefield = TREE_CHAIN (basefield))
1335
              if (TREE_CODE (basefield) == FIELD_DECL)
1336
                {
1337
                  if (field)
1338
                    CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1339
                  else
1340
                    field = basefield;
1341
                  break;
1342
                }
1343
        }
1344
    }
1345
}
1346
 
1347
/* Determine all the primary bases within T.  Sets BINFO_PRIMARY_BASE_P for
1348
   those that are primaries.  Sets BINFO_LOST_PRIMARY_P for those
1349
   that have had a nearly-empty virtual primary base stolen by some
1350
   other base in the hierarchy.  Determines CLASSTYPE_PRIMARY_BASE for
1351
   T.  */
1352
 
1353
static void
1354
determine_primary_bases (tree t)
1355
{
1356
  unsigned i;
1357
  tree primary = NULL_TREE;
1358
  tree type_binfo = TYPE_BINFO (t);
1359
  tree base_binfo;
1360
 
1361
  /* Determine the primary bases of our bases.  */
1362
  for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1363
       base_binfo = TREE_CHAIN (base_binfo))
1364
    {
1365
      tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1366
 
1367
      /* See if we're the non-virtual primary of our inheritance
1368
         chain.  */
1369
      if (!BINFO_VIRTUAL_P (base_binfo))
1370
        {
1371
          tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1372
          tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1373
 
1374
          if (parent_primary
1375
              && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1376
                                    BINFO_TYPE (parent_primary)))
1377
            /* We are the primary binfo.  */
1378
            BINFO_PRIMARY_P (base_binfo) = 1;
1379
        }
1380
      /* Determine if we have a virtual primary base, and mark it so.
1381
       */
1382
      if (primary && BINFO_VIRTUAL_P (primary))
1383
        {
1384
          tree this_primary = copied_binfo (primary, base_binfo);
1385
 
1386
          if (BINFO_PRIMARY_P (this_primary))
1387
            /* Someone already claimed this base.  */
1388
            BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1389
          else
1390
            {
1391
              tree delta;
1392
 
1393
              BINFO_PRIMARY_P (this_primary) = 1;
1394
              BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1395
 
1396
              /* A virtual binfo might have been copied from within
1397
                 another hierarchy. As we're about to use it as a
1398
                 primary base, make sure the offsets match.  */
1399
              delta = size_diffop_loc (input_location,
1400
                                   convert (ssizetype,
1401
                                            BINFO_OFFSET (base_binfo)),
1402
                                   convert (ssizetype,
1403
                                            BINFO_OFFSET (this_primary)));
1404
 
1405
              propagate_binfo_offsets (this_primary, delta);
1406
            }
1407
        }
1408
    }
1409
 
1410
  /* First look for a dynamic direct non-virtual base.  */
1411
  for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1412
    {
1413
      tree basetype = BINFO_TYPE (base_binfo);
1414
 
1415
      if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1416
        {
1417
          primary = base_binfo;
1418
          goto found;
1419
        }
1420
    }
1421
 
1422
  /* A "nearly-empty" virtual base class can be the primary base
1423
     class, if no non-virtual polymorphic base can be found.  Look for
1424
     a nearly-empty virtual dynamic base that is not already a primary
1425
     base of something in the hierarchy.  If there is no such base,
1426
     just pick the first nearly-empty virtual base.  */
1427
 
1428
  for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1429
       base_binfo = TREE_CHAIN (base_binfo))
1430
    if (BINFO_VIRTUAL_P (base_binfo)
1431
        && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1432
      {
1433
        if (!BINFO_PRIMARY_P (base_binfo))
1434
          {
1435
            /* Found one that is not primary.  */
1436
            primary = base_binfo;
1437
            goto found;
1438
          }
1439
        else if (!primary)
1440
          /* Remember the first candidate.  */
1441
          primary = base_binfo;
1442
      }
1443
 
1444
 found:
1445
  /* If we've got a primary base, use it.  */
1446
  if (primary)
1447
    {
1448
      tree basetype = BINFO_TYPE (primary);
1449
 
1450
      CLASSTYPE_PRIMARY_BINFO (t) = primary;
1451
      if (BINFO_PRIMARY_P (primary))
1452
        /* We are stealing a primary base.  */
1453
        BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1454
      BINFO_PRIMARY_P (primary) = 1;
1455
      if (BINFO_VIRTUAL_P (primary))
1456
        {
1457
          tree delta;
1458
 
1459
          BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1460
          /* A virtual binfo might have been copied from within
1461
             another hierarchy. As we're about to use it as a primary
1462
             base, make sure the offsets match.  */
1463
          delta = size_diffop_loc (input_location, ssize_int (0),
1464
                               convert (ssizetype, BINFO_OFFSET (primary)));
1465
 
1466
          propagate_binfo_offsets (primary, delta);
1467
        }
1468
 
1469
      primary = TYPE_BINFO (basetype);
1470
 
1471
      TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1472
      BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1473
      BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1474
    }
1475
}
1476
 
1477
/* Update the variant types of T.  */
1478
 
1479
void
1480
fixup_type_variants (tree t)
1481
{
1482
  tree variants;
1483
 
1484
  if (!t)
1485
    return;
1486
 
1487
  for (variants = TYPE_NEXT_VARIANT (t);
1488
       variants;
1489
       variants = TYPE_NEXT_VARIANT (variants))
1490
    {
1491
      /* These fields are in the _TYPE part of the node, not in
1492
         the TYPE_LANG_SPECIFIC component, so they are not shared.  */
1493
      TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1494
      TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1495
      TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1496
        = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1497
 
1498
      TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1499
 
1500
      TYPE_BINFO (variants) = TYPE_BINFO (t);
1501
 
1502
      /* Copy whatever these are holding today.  */
1503
      TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1504
      TYPE_METHODS (variants) = TYPE_METHODS (t);
1505
      TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1506
 
1507
      /* All variants of a class have the same attributes.  */
1508
      TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1509
    }
1510
}
1511
 
1512
 
1513
/* Set memoizing fields and bits of T (and its variants) for later
1514
   use.  */
1515
 
1516
static void
1517
finish_struct_bits (tree t)
1518
{
1519
  /* Fix up variants (if any).  */
1520
  fixup_type_variants (t);
1521
 
1522
  if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1523
    /* For a class w/o baseclasses, 'finish_struct' has set
1524
       CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1525
       Similarly for a class whose base classes do not have vtables.
1526
       When neither of these is true, we might have removed abstract
1527
       virtuals (by providing a definition), added some (by declaring
1528
       new ones), or redeclared ones from a base class.  We need to
1529
       recalculate what's really an abstract virtual at this point (by
1530
       looking in the vtables).  */
1531
    get_pure_virtuals (t);
1532
 
1533
  /* If this type has a copy constructor or a destructor, force its
1534
     mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1535
     nonzero.  This will cause it to be passed by invisible reference
1536
     and prevent it from being returned in a register.  */
1537
  if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1538
    {
1539
      tree variants;
1540
      DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1541
      for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1542
        {
1543
          SET_TYPE_MODE (variants, BLKmode);
1544
          TREE_ADDRESSABLE (variants) = 1;
1545
        }
1546
    }
1547
}
1548
 
1549
/* Issue warnings about T having private constructors, but no friends,
1550
   and so forth.
1551
 
1552
   HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1553
   static members.  HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1554
   non-private static member functions.  */
1555
 
1556
static void
1557
maybe_warn_about_overly_private_class (tree t)
1558
{
1559
  int has_member_fn = 0;
1560
  int has_nonprivate_method = 0;
1561
  tree fn;
1562
 
1563
  if (!warn_ctor_dtor_privacy
1564
      /* If the class has friends, those entities might create and
1565
         access instances, so we should not warn.  */
1566
      || (CLASSTYPE_FRIEND_CLASSES (t)
1567
          || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1568
      /* We will have warned when the template was declared; there's
1569
         no need to warn on every instantiation.  */
1570
      || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1571
    /* There's no reason to even consider warning about this
1572
       class.  */
1573
    return;
1574
 
1575
  /* We only issue one warning, if more than one applies, because
1576
     otherwise, on code like:
1577
 
1578
     class A {
1579
       // Oops - forgot `public:'
1580
       A();
1581
       A(const A&);
1582
       ~A();
1583
     };
1584
 
1585
     we warn several times about essentially the same problem.  */
1586
 
1587
  /* Check to see if all (non-constructor, non-destructor) member
1588
     functions are private.  (Since there are no friends or
1589
     non-private statics, we can't ever call any of the private member
1590
     functions.)  */
1591
  for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1592
    /* We're not interested in compiler-generated methods; they don't
1593
       provide any way to call private members.  */
1594
    if (!DECL_ARTIFICIAL (fn))
1595
      {
1596
        if (!TREE_PRIVATE (fn))
1597
          {
1598
            if (DECL_STATIC_FUNCTION_P (fn))
1599
              /* A non-private static member function is just like a
1600
                 friend; it can create and invoke private member
1601
                 functions, and be accessed without a class
1602
                 instance.  */
1603
              return;
1604
 
1605
            has_nonprivate_method = 1;
1606
            /* Keep searching for a static member function.  */
1607
          }
1608
        else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1609
          has_member_fn = 1;
1610
      }
1611
 
1612
  if (!has_nonprivate_method && has_member_fn)
1613
    {
1614
      /* There are no non-private methods, and there's at least one
1615
         private member function that isn't a constructor or
1616
         destructor.  (If all the private members are
1617
         constructors/destructors we want to use the code below that
1618
         issues error messages specifically referring to
1619
         constructors/destructors.)  */
1620
      unsigned i;
1621
      tree binfo = TYPE_BINFO (t);
1622
 
1623
      for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1624
        if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1625
          {
1626
            has_nonprivate_method = 1;
1627
            break;
1628
          }
1629
      if (!has_nonprivate_method)
1630
        {
1631
          warning (OPT_Wctor_dtor_privacy,
1632
                   "all member functions in class %qT are private", t);
1633
          return;
1634
        }
1635
    }
1636
 
1637
  /* Even if some of the member functions are non-private, the class
1638
     won't be useful for much if all the constructors or destructors
1639
     are private: such an object can never be created or destroyed.  */
1640
  fn = CLASSTYPE_DESTRUCTORS (t);
1641
  if (fn && TREE_PRIVATE (fn))
1642
    {
1643
      warning (OPT_Wctor_dtor_privacy,
1644
               "%q#T only defines a private destructor and has no friends",
1645
               t);
1646
      return;
1647
    }
1648
 
1649
  /* Warn about classes that have private constructors and no friends.  */
1650
  if (TYPE_HAS_USER_CONSTRUCTOR (t)
1651
      /* Implicitly generated constructors are always public.  */
1652
      && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1653
          || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1654
    {
1655
      int nonprivate_ctor = 0;
1656
 
1657
      /* If a non-template class does not define a copy
1658
         constructor, one is defined for it, enabling it to avoid
1659
         this warning.  For a template class, this does not
1660
         happen, and so we would normally get a warning on:
1661
 
1662
           template <class T> class C { private: C(); };
1663
 
1664
         To avoid this asymmetry, we check TYPE_HAS_INIT_REF.  All
1665
         complete non-template or fully instantiated classes have this
1666
         flag set.  */
1667
      if (!TYPE_HAS_INIT_REF (t))
1668
        nonprivate_ctor = 1;
1669
      else
1670
        for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1671
          {
1672
            tree ctor = OVL_CURRENT (fn);
1673
            /* Ideally, we wouldn't count copy constructors (or, in
1674
               fact, any constructor that takes an argument of the
1675
               class type as a parameter) because such things cannot
1676
               be used to construct an instance of the class unless
1677
               you already have one.  But, for now at least, we're
1678
               more generous.  */
1679
            if (! TREE_PRIVATE (ctor))
1680
              {
1681
                nonprivate_ctor = 1;
1682
                break;
1683
              }
1684
          }
1685
 
1686
      if (nonprivate_ctor == 0)
1687
        {
1688
          warning (OPT_Wctor_dtor_privacy,
1689
                   "%q#T only defines private constructors and has no friends",
1690
                   t);
1691
          return;
1692
        }
1693
    }
1694
}
1695
 
1696
static struct {
1697
  gt_pointer_operator new_value;
1698
  void *cookie;
1699
} resort_data;
1700
 
1701
/* Comparison function to compare two TYPE_METHOD_VEC entries by name.  */
1702
 
1703
static int
1704
method_name_cmp (const void* m1_p, const void* m2_p)
1705
{
1706
  const tree *const m1 = (const tree *) m1_p;
1707
  const tree *const m2 = (const tree *) m2_p;
1708
 
1709
  if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1710
    return 0;
1711
  if (*m1 == NULL_TREE)
1712
    return -1;
1713
  if (*m2 == NULL_TREE)
1714
    return 1;
1715
  if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1716
    return -1;
1717
  return 1;
1718
}
1719
 
1720
/* This routine compares two fields like method_name_cmp but using the
1721
   pointer operator in resort_field_decl_data.  */
1722
 
1723
static int
1724
resort_method_name_cmp (const void* m1_p, const void* m2_p)
1725
{
1726
  const tree *const m1 = (const tree *) m1_p;
1727
  const tree *const m2 = (const tree *) m2_p;
1728
  if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1729
    return 0;
1730
  if (*m1 == NULL_TREE)
1731
    return -1;
1732
  if (*m2 == NULL_TREE)
1733
    return 1;
1734
  {
1735
    tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1736
    tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1737
    resort_data.new_value (&d1, resort_data.cookie);
1738
    resort_data.new_value (&d2, resort_data.cookie);
1739
    if (d1 < d2)
1740
      return -1;
1741
  }
1742
  return 1;
1743
}
1744
 
1745
/* Resort TYPE_METHOD_VEC because pointers have been reordered.  */
1746
 
1747
void
1748
resort_type_method_vec (void* obj,
1749
                        void* orig_obj ATTRIBUTE_UNUSED ,
1750
                        gt_pointer_operator new_value,
1751
                        void* cookie)
1752
{
1753
  VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1754
  int len = VEC_length (tree, method_vec);
1755
  size_t slot;
1756
  tree fn;
1757
 
1758
  /* The type conversion ops have to live at the front of the vec, so we
1759
     can't sort them.  */
1760
  for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1761
       VEC_iterate (tree, method_vec, slot, fn);
1762
       ++slot)
1763
    if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1764
      break;
1765
 
1766
  if (len - slot > 1)
1767
    {
1768
      resort_data.new_value = new_value;
1769
      resort_data.cookie = cookie;
1770
      qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1771
             resort_method_name_cmp);
1772
    }
1773
}
1774
 
1775
/* Warn about duplicate methods in fn_fields.
1776
 
1777
   Sort methods that are not special (i.e., constructors, destructors,
1778
   and type conversion operators) so that we can find them faster in
1779
   search.  */
1780
 
1781
static void
1782
finish_struct_methods (tree t)
1783
{
1784
  tree fn_fields;
1785
  VEC(tree,gc) *method_vec;
1786
  int slot, len;
1787
 
1788
  method_vec = CLASSTYPE_METHOD_VEC (t);
1789
  if (!method_vec)
1790
    return;
1791
 
1792
  len = VEC_length (tree, method_vec);
1793
 
1794
  /* Clear DECL_IN_AGGR_P for all functions.  */
1795
  for (fn_fields = TYPE_METHODS (t); fn_fields;
1796
       fn_fields = TREE_CHAIN (fn_fields))
1797
    DECL_IN_AGGR_P (fn_fields) = 0;
1798
 
1799
  /* Issue warnings about private constructors and such.  If there are
1800
     no methods, then some public defaults are generated.  */
1801
  maybe_warn_about_overly_private_class (t);
1802
 
1803
  /* The type conversion ops have to live at the front of the vec, so we
1804
     can't sort them.  */
1805
  for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1806
       VEC_iterate (tree, method_vec, slot, fn_fields);
1807
       ++slot)
1808
    if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1809
      break;
1810
  if (len - slot > 1)
1811
    qsort (VEC_address (tree, method_vec) + slot,
1812
           len-slot, sizeof (tree), method_name_cmp);
1813
}
1814
 
1815
/* Make BINFO's vtable have N entries, including RTTI entries,
1816
   vbase and vcall offsets, etc.  Set its type and call the back end
1817
   to lay it out.  */
1818
 
1819
static void
1820
layout_vtable_decl (tree binfo, int n)
1821
{
1822
  tree atype;
1823
  tree vtable;
1824
 
1825
  atype = build_cplus_array_type (vtable_entry_type,
1826
                                  build_index_type (size_int (n - 1)));
1827
  layout_type (atype);
1828
 
1829
  /* We may have to grow the vtable.  */
1830
  vtable = get_vtbl_decl_for_binfo (binfo);
1831
  if (!same_type_p (TREE_TYPE (vtable), atype))
1832
    {
1833
      TREE_TYPE (vtable) = atype;
1834
      DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1835
      layout_decl (vtable, 0);
1836
    }
1837
}
1838
 
1839
/* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1840
   have the same signature.  */
1841
 
1842
int
1843
same_signature_p (const_tree fndecl, const_tree base_fndecl)
1844
{
1845
  /* One destructor overrides another if they are the same kind of
1846
     destructor.  */
1847
  if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1848
      && special_function_p (base_fndecl) == special_function_p (fndecl))
1849
    return 1;
1850
  /* But a non-destructor never overrides a destructor, nor vice
1851
     versa, nor do different kinds of destructors override
1852
     one-another.  For example, a complete object destructor does not
1853
     override a deleting destructor.  */
1854
  if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1855
    return 0;
1856
 
1857
  if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1858
      || (DECL_CONV_FN_P (fndecl)
1859
          && DECL_CONV_FN_P (base_fndecl)
1860
          && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1861
                          DECL_CONV_FN_TYPE (base_fndecl))))
1862
    {
1863
      tree types, base_types;
1864
      types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1865
      base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1866
      if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1867
           == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1868
          && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1869
        return 1;
1870
    }
1871
  return 0;
1872
}
1873
 
1874
/* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1875
   subobject.  */
1876
 
1877
static bool
1878
base_derived_from (tree derived, tree base)
1879
{
1880
  tree probe;
1881
 
1882
  for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1883
    {
1884
      if (probe == derived)
1885
        return true;
1886
      else if (BINFO_VIRTUAL_P (probe))
1887
        /* If we meet a virtual base, we can't follow the inheritance
1888
           any more.  See if the complete type of DERIVED contains
1889
           such a virtual base.  */
1890
        return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1891
                != NULL_TREE);
1892
    }
1893
  return false;
1894
}
1895
 
1896
typedef struct find_final_overrider_data_s {
1897
  /* The function for which we are trying to find a final overrider.  */
1898
  tree fn;
1899
  /* The base class in which the function was declared.  */
1900
  tree declaring_base;
1901
  /* The candidate overriders.  */
1902
  tree candidates;
1903
  /* Path to most derived.  */
1904
  VEC(tree,heap) *path;
1905
} find_final_overrider_data;
1906
 
1907
/* Add the overrider along the current path to FFOD->CANDIDATES.
1908
   Returns true if an overrider was found; false otherwise.  */
1909
 
1910
static bool
1911
dfs_find_final_overrider_1 (tree binfo,
1912
                            find_final_overrider_data *ffod,
1913
                            unsigned depth)
1914
{
1915
  tree method;
1916
 
1917
  /* If BINFO is not the most derived type, try a more derived class.
1918
     A definition there will overrider a definition here.  */
1919
  if (depth)
1920
    {
1921
      depth--;
1922
      if (dfs_find_final_overrider_1
1923
          (VEC_index (tree, ffod->path, depth), ffod, depth))
1924
        return true;
1925
    }
1926
 
1927
  method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1928
  if (method)
1929
    {
1930
      tree *candidate = &ffod->candidates;
1931
 
1932
      /* Remove any candidates overridden by this new function.  */
1933
      while (*candidate)
1934
        {
1935
          /* If *CANDIDATE overrides METHOD, then METHOD
1936
             cannot override anything else on the list.  */
1937
          if (base_derived_from (TREE_VALUE (*candidate), binfo))
1938
            return true;
1939
          /* If METHOD overrides *CANDIDATE, remove *CANDIDATE.  */
1940
          if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1941
            *candidate = TREE_CHAIN (*candidate);
1942
          else
1943
            candidate = &TREE_CHAIN (*candidate);
1944
        }
1945
 
1946
      /* Add the new function.  */
1947
      ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1948
      return true;
1949
    }
1950
 
1951
  return false;
1952
}
1953
 
1954
/* Called from find_final_overrider via dfs_walk.  */
1955
 
1956
static tree
1957
dfs_find_final_overrider_pre (tree binfo, void *data)
1958
{
1959
  find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1960
 
1961
  if (binfo == ffod->declaring_base)
1962
    dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1963
  VEC_safe_push (tree, heap, ffod->path, binfo);
1964
 
1965
  return NULL_TREE;
1966
}
1967
 
1968
static tree
1969
dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1970
{
1971
  find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1972
  VEC_pop (tree, ffod->path);
1973
 
1974
  return NULL_TREE;
1975
}
1976
 
1977
/* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1978
   FN and whose TREE_VALUE is the binfo for the base where the
1979
   overriding occurs.  BINFO (in the hierarchy dominated by the binfo
1980
   DERIVED) is the base object in which FN is declared.  */
1981
 
1982
static tree
1983
find_final_overrider (tree derived, tree binfo, tree fn)
1984
{
1985
  find_final_overrider_data ffod;
1986
 
1987
  /* Getting this right is a little tricky.  This is valid:
1988
 
1989
       struct S { virtual void f (); };
1990
       struct T { virtual void f (); };
1991
       struct U : public S, public T { };
1992
 
1993
     even though calling `f' in `U' is ambiguous.  But,
1994
 
1995
       struct R { virtual void f(); };
1996
       struct S : virtual public R { virtual void f (); };
1997
       struct T : virtual public R { virtual void f (); };
1998
       struct U : public S, public T { };
1999
 
2000
     is not -- there's no way to decide whether to put `S::f' or
2001
     `T::f' in the vtable for `R'.
2002
 
2003
     The solution is to look at all paths to BINFO.  If we find
2004
     different overriders along any two, then there is a problem.  */
2005
  if (DECL_THUNK_P (fn))
2006
    fn = THUNK_TARGET (fn);
2007
 
2008
  /* Determine the depth of the hierarchy.  */
2009
  ffod.fn = fn;
2010
  ffod.declaring_base = binfo;
2011
  ffod.candidates = NULL_TREE;
2012
  ffod.path = VEC_alloc (tree, heap, 30);
2013
 
2014
  dfs_walk_all (derived, dfs_find_final_overrider_pre,
2015
                dfs_find_final_overrider_post, &ffod);
2016
 
2017
  VEC_free (tree, heap, ffod.path);
2018
 
2019
  /* If there was no winner, issue an error message.  */
2020
  if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2021
    return error_mark_node;
2022
 
2023
  return ffod.candidates;
2024
}
2025
 
2026
/* Return the index of the vcall offset for FN when TYPE is used as a
2027
   virtual base.  */
2028
 
2029
static tree
2030
get_vcall_index (tree fn, tree type)
2031
{
2032
  VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2033
  tree_pair_p p;
2034
  unsigned ix;
2035
 
2036
  for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
2037
    if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2038
        || same_signature_p (fn, p->purpose))
2039
      return p->value;
2040
 
2041
  /* There should always be an appropriate index.  */
2042
  gcc_unreachable ();
2043
}
2044
 
2045
/* Update an entry in the vtable for BINFO, which is in the hierarchy
2046
   dominated by T.  FN has been overridden in BINFO; VIRTUALS points to the
2047
   corresponding position in the BINFO_VIRTUALS list.  */
2048
 
2049
static void
2050
update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2051
                            unsigned ix)
2052
{
2053
  tree b;
2054
  tree overrider;
2055
  tree delta;
2056
  tree virtual_base;
2057
  tree first_defn;
2058
  tree overrider_fn, overrider_target;
2059
  tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2060
  tree over_return, base_return;
2061
  bool lost = false;
2062
 
2063
  /* Find the nearest primary base (possibly binfo itself) which defines
2064
     this function; this is the class the caller will convert to when
2065
     calling FN through BINFO.  */
2066
  for (b = binfo; ; b = get_primary_binfo (b))
2067
    {
2068
      gcc_assert (b);
2069
      if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2070
        break;
2071
 
2072
      /* The nearest definition is from a lost primary.  */
2073
      if (BINFO_LOST_PRIMARY_P (b))
2074
        lost = true;
2075
    }
2076
  first_defn = b;
2077
 
2078
  /* Find the final overrider.  */
2079
  overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2080
  if (overrider == error_mark_node)
2081
    {
2082
      error ("no unique final overrider for %qD in %qT", target_fn, t);
2083
      return;
2084
    }
2085
  overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2086
 
2087
  /* Check for adjusting covariant return types.  */
2088
  over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2089
  base_return = TREE_TYPE (TREE_TYPE (target_fn));
2090
 
2091
  if (POINTER_TYPE_P (over_return)
2092
      && TREE_CODE (over_return) == TREE_CODE (base_return)
2093
      && CLASS_TYPE_P (TREE_TYPE (over_return))
2094
      && CLASS_TYPE_P (TREE_TYPE (base_return))
2095
      /* If the overrider is invalid, don't even try.  */
2096
      && !DECL_INVALID_OVERRIDER_P (overrider_target))
2097
    {
2098
      /* If FN is a covariant thunk, we must figure out the adjustment
2099
         to the final base FN was converting to. As OVERRIDER_TARGET might
2100
         also be converting to the return type of FN, we have to
2101
         combine the two conversions here.  */
2102
      tree fixed_offset, virtual_offset;
2103
 
2104
      over_return = TREE_TYPE (over_return);
2105
      base_return = TREE_TYPE (base_return);
2106
 
2107
      if (DECL_THUNK_P (fn))
2108
        {
2109
          gcc_assert (DECL_RESULT_THUNK_P (fn));
2110
          fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2111
          virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2112
        }
2113
      else
2114
        fixed_offset = virtual_offset = NULL_TREE;
2115
 
2116
      if (virtual_offset)
2117
        /* Find the equivalent binfo within the return type of the
2118
           overriding function. We will want the vbase offset from
2119
           there.  */
2120
        virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2121
                                          over_return);
2122
      else if (!same_type_ignoring_top_level_qualifiers_p
2123
               (over_return, base_return))
2124
        {
2125
          /* There was no existing virtual thunk (which takes
2126
             precedence).  So find the binfo of the base function's
2127
             return type within the overriding function's return type.
2128
             We cannot call lookup base here, because we're inside a
2129
             dfs_walk, and will therefore clobber the BINFO_MARKED
2130
             flags.  Fortunately we know the covariancy is valid (it
2131
             has already been checked), so we can just iterate along
2132
             the binfos, which have been chained in inheritance graph
2133
             order.  Of course it is lame that we have to repeat the
2134
             search here anyway -- we should really be caching pieces
2135
             of the vtable and avoiding this repeated work.  */
2136
          tree thunk_binfo, base_binfo;
2137
 
2138
          /* Find the base binfo within the overriding function's
2139
             return type.  We will always find a thunk_binfo, except
2140
             when the covariancy is invalid (which we will have
2141
             already diagnosed).  */
2142
          for (base_binfo = TYPE_BINFO (base_return),
2143
               thunk_binfo = TYPE_BINFO (over_return);
2144
               thunk_binfo;
2145
               thunk_binfo = TREE_CHAIN (thunk_binfo))
2146
            if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2147
                                   BINFO_TYPE (base_binfo)))
2148
              break;
2149
 
2150
          /* See if virtual inheritance is involved.  */
2151
          for (virtual_offset = thunk_binfo;
2152
               virtual_offset;
2153
               virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2154
            if (BINFO_VIRTUAL_P (virtual_offset))
2155
              break;
2156
 
2157
          if (virtual_offset
2158
              || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2159
            {
2160
              tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2161
 
2162
              if (virtual_offset)
2163
                {
2164
                  /* We convert via virtual base.  Adjust the fixed
2165
                     offset to be from there.  */
2166
                  offset =
2167
                    size_diffop (offset,
2168
                                 convert (ssizetype,
2169
                                          BINFO_OFFSET (virtual_offset)));
2170
                }
2171
              if (fixed_offset)
2172
                /* There was an existing fixed offset, this must be
2173
                   from the base just converted to, and the base the
2174
                   FN was thunking to.  */
2175
                fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2176
              else
2177
                fixed_offset = offset;
2178
            }
2179
        }
2180
 
2181
      if (fixed_offset || virtual_offset)
2182
        /* Replace the overriding function with a covariant thunk.  We
2183
           will emit the overriding function in its own slot as
2184
           well.  */
2185
        overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2186
                                   fixed_offset, virtual_offset);
2187
    }
2188
  else
2189
    gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2190
                !DECL_THUNK_P (fn));
2191
 
2192
  /* Assume that we will produce a thunk that convert all the way to
2193
     the final overrider, and not to an intermediate virtual base.  */
2194
  virtual_base = NULL_TREE;
2195
 
2196
  /* See if we can convert to an intermediate virtual base first, and then
2197
     use the vcall offset located there to finish the conversion.  */
2198
  for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2199
    {
2200
      /* If we find the final overrider, then we can stop
2201
         walking.  */
2202
      if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2203
                             BINFO_TYPE (TREE_VALUE (overrider))))
2204
        break;
2205
 
2206
      /* If we find a virtual base, and we haven't yet found the
2207
         overrider, then there is a virtual base between the
2208
         declaring base (first_defn) and the final overrider.  */
2209
      if (BINFO_VIRTUAL_P (b))
2210
        {
2211
          virtual_base = b;
2212
          break;
2213
        }
2214
    }
2215
 
2216
  if (overrider_fn != overrider_target && !virtual_base)
2217
    {
2218
      /* The ABI specifies that a covariant thunk includes a mangling
2219
         for a this pointer adjustment.  This-adjusting thunks that
2220
         override a function from a virtual base have a vcall
2221
         adjustment.  When the virtual base in question is a primary
2222
         virtual base, we know the adjustments are zero, (and in the
2223
         non-covariant case, we would not use the thunk).
2224
         Unfortunately we didn't notice this could happen, when
2225
         designing the ABI and so never mandated that such a covariant
2226
         thunk should be emitted.  Because we must use the ABI mandated
2227
         name, we must continue searching from the binfo where we
2228
         found the most recent definition of the function, towards the
2229
         primary binfo which first introduced the function into the
2230
         vtable.  If that enters a virtual base, we must use a vcall
2231
         this-adjusting thunk.  Bleah! */
2232
      tree probe = first_defn;
2233
 
2234
      while ((probe = get_primary_binfo (probe))
2235
             && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2236
        if (BINFO_VIRTUAL_P (probe))
2237
          virtual_base = probe;
2238
 
2239
      if (virtual_base)
2240
        /* Even if we find a virtual base, the correct delta is
2241
           between the overrider and the binfo we're building a vtable
2242
           for.  */
2243
        goto virtual_covariant;
2244
    }
2245
 
2246
  /* Compute the constant adjustment to the `this' pointer.  The
2247
     `this' pointer, when this function is called, will point at BINFO
2248
     (or one of its primary bases, which are at the same offset).  */
2249
  if (virtual_base)
2250
    /* The `this' pointer needs to be adjusted from the declaration to
2251
       the nearest virtual base.  */
2252
    delta = size_diffop_loc (input_location,
2253
                         convert (ssizetype, BINFO_OFFSET (virtual_base)),
2254
                         convert (ssizetype, BINFO_OFFSET (first_defn)));
2255
  else if (lost)
2256
    /* If the nearest definition is in a lost primary, we don't need an
2257
       entry in our vtable.  Except possibly in a constructor vtable,
2258
       if we happen to get our primary back.  In that case, the offset
2259
       will be zero, as it will be a primary base.  */
2260
    delta = size_zero_node;
2261
  else
2262
    /* The `this' pointer needs to be adjusted from pointing to
2263
       BINFO to pointing at the base where the final overrider
2264
       appears.  */
2265
    virtual_covariant:
2266
    delta = size_diffop_loc (input_location,
2267
                         convert (ssizetype,
2268
                                  BINFO_OFFSET (TREE_VALUE (overrider))),
2269
                         convert (ssizetype, BINFO_OFFSET (binfo)));
2270
 
2271
  modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2272
 
2273
  if (virtual_base)
2274
    BV_VCALL_INDEX (*virtuals)
2275
      = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2276
  else
2277
    BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2278
}
2279
 
2280
/* Called from modify_all_vtables via dfs_walk.  */
2281
 
2282
static tree
2283
dfs_modify_vtables (tree binfo, void* data)
2284
{
2285
  tree t = (tree) data;
2286
  tree virtuals;
2287
  tree old_virtuals;
2288
  unsigned ix;
2289
 
2290
  if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2291
    /* A base without a vtable needs no modification, and its bases
2292
       are uninteresting.  */
2293
    return dfs_skip_bases;
2294
 
2295
  if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2296
      && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2297
    /* Don't do the primary vtable, if it's new.  */
2298
    return NULL_TREE;
2299
 
2300
  if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2301
    /* There's no need to modify the vtable for a non-virtual primary
2302
       base; we're not going to use that vtable anyhow.  We do still
2303
       need to do this for virtual primary bases, as they could become
2304
       non-primary in a construction vtable.  */
2305
    return NULL_TREE;
2306
 
2307
  make_new_vtable (t, binfo);
2308
 
2309
  /* Now, go through each of the virtual functions in the virtual
2310
     function table for BINFO.  Find the final overrider, and update
2311
     the BINFO_VIRTUALS list appropriately.  */
2312
  for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2313
         old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2314
       virtuals;
2315
       ix++, virtuals = TREE_CHAIN (virtuals),
2316
         old_virtuals = TREE_CHAIN (old_virtuals))
2317
    update_vtable_entry_for_fn (t,
2318
                                binfo,
2319
                                BV_FN (old_virtuals),
2320
                                &virtuals, ix);
2321
 
2322
  return NULL_TREE;
2323
}
2324
 
2325
/* Update all of the primary and secondary vtables for T.  Create new
2326
   vtables as required, and initialize their RTTI information.  Each
2327
   of the functions in VIRTUALS is declared in T and may override a
2328
   virtual function from a base class; find and modify the appropriate
2329
   entries to point to the overriding functions.  Returns a list, in
2330
   declaration order, of the virtual functions that are declared in T,
2331
   but do not appear in the primary base class vtable, and which
2332
   should therefore be appended to the end of the vtable for T.  */
2333
 
2334
static tree
2335
modify_all_vtables (tree t, tree virtuals)
2336
{
2337
  tree binfo = TYPE_BINFO (t);
2338
  tree *fnsp;
2339
 
2340
  /* Update all of the vtables.  */
2341
  dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2342
 
2343
  /* Add virtual functions not already in our primary vtable. These
2344
     will be both those introduced by this class, and those overridden
2345
     from secondary bases.  It does not include virtuals merely
2346
     inherited from secondary bases.  */
2347
  for (fnsp = &virtuals; *fnsp; )
2348
    {
2349
      tree fn = TREE_VALUE (*fnsp);
2350
 
2351
      if (!value_member (fn, BINFO_VIRTUALS (binfo))
2352
          || DECL_VINDEX (fn) == error_mark_node)
2353
        {
2354
          /* We don't need to adjust the `this' pointer when
2355
             calling this function.  */
2356
          BV_DELTA (*fnsp) = integer_zero_node;
2357
          BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2358
 
2359
          /* This is a function not already in our vtable.  Keep it.  */
2360
          fnsp = &TREE_CHAIN (*fnsp);
2361
        }
2362
      else
2363
        /* We've already got an entry for this function.  Skip it.  */
2364
        *fnsp = TREE_CHAIN (*fnsp);
2365
    }
2366
 
2367
  return virtuals;
2368
}
2369
 
2370
/* Get the base virtual function declarations in T that have the
2371
   indicated NAME.  */
2372
 
2373
static tree
2374
get_basefndecls (tree name, tree t)
2375
{
2376
  tree methods;
2377
  tree base_fndecls = NULL_TREE;
2378
  int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2379
  int i;
2380
 
2381
  /* Find virtual functions in T with the indicated NAME.  */
2382
  i = lookup_fnfields_1 (t, name);
2383
  if (i != -1)
2384
    for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2385
         methods;
2386
         methods = OVL_NEXT (methods))
2387
      {
2388
        tree method = OVL_CURRENT (methods);
2389
 
2390
        if (TREE_CODE (method) == FUNCTION_DECL
2391
            && DECL_VINDEX (method))
2392
          base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2393
      }
2394
 
2395
  if (base_fndecls)
2396
    return base_fndecls;
2397
 
2398
  for (i = 0; i < n_baseclasses; i++)
2399
    {
2400
      tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2401
      base_fndecls = chainon (get_basefndecls (name, basetype),
2402
                              base_fndecls);
2403
    }
2404
 
2405
  return base_fndecls;
2406
}
2407
 
2408
/* If this declaration supersedes the declaration of
2409
   a method declared virtual in the base class, then
2410
   mark this field as being virtual as well.  */
2411
 
2412
void
2413
check_for_override (tree decl, tree ctype)
2414
{
2415
  if (TREE_CODE (decl) == TEMPLATE_DECL)
2416
    /* In [temp.mem] we have:
2417
 
2418
         A specialization of a member function template does not
2419
         override a virtual function from a base class.  */
2420
    return;
2421
  if ((DECL_DESTRUCTOR_P (decl)
2422
       || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2423
       || DECL_CONV_FN_P (decl))
2424
      && look_for_overrides (ctype, decl)
2425
      && !DECL_STATIC_FUNCTION_P (decl))
2426
    /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2427
       the error_mark_node so that we know it is an overriding
2428
       function.  */
2429
    DECL_VINDEX (decl) = decl;
2430
 
2431
  if (DECL_VIRTUAL_P (decl))
2432
    {
2433
      if (!DECL_VINDEX (decl))
2434
        DECL_VINDEX (decl) = error_mark_node;
2435
      IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2436
    }
2437
}
2438
 
2439
/* Warn about hidden virtual functions that are not overridden in t.
2440
   We know that constructors and destructors don't apply.  */
2441
 
2442
static void
2443
warn_hidden (tree t)
2444
{
2445
  VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2446
  tree fns;
2447
  size_t i;
2448
 
2449
  /* We go through each separately named virtual function.  */
2450
  for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2451
       VEC_iterate (tree, method_vec, i, fns);
2452
       ++i)
2453
    {
2454
      tree fn;
2455
      tree name;
2456
      tree fndecl;
2457
      tree base_fndecls;
2458
      tree base_binfo;
2459
      tree binfo;
2460
      int j;
2461
 
2462
      /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2463
         have the same name.  Figure out what name that is.  */
2464
      name = DECL_NAME (OVL_CURRENT (fns));
2465
      /* There are no possibly hidden functions yet.  */
2466
      base_fndecls = NULL_TREE;
2467
      /* Iterate through all of the base classes looking for possibly
2468
         hidden functions.  */
2469
      for (binfo = TYPE_BINFO (t), j = 0;
2470
           BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2471
        {
2472
          tree basetype = BINFO_TYPE (base_binfo);
2473
          base_fndecls = chainon (get_basefndecls (name, basetype),
2474
                                  base_fndecls);
2475
        }
2476
 
2477
      /* If there are no functions to hide, continue.  */
2478
      if (!base_fndecls)
2479
        continue;
2480
 
2481
      /* Remove any overridden functions.  */
2482
      for (fn = fns; fn; fn = OVL_NEXT (fn))
2483
        {
2484
          fndecl = OVL_CURRENT (fn);
2485
          if (DECL_VINDEX (fndecl))
2486
            {
2487
              tree *prev = &base_fndecls;
2488
 
2489
              while (*prev)
2490
                /* If the method from the base class has the same
2491
                   signature as the method from the derived class, it
2492
                   has been overridden.  */
2493
                if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2494
                  *prev = TREE_CHAIN (*prev);
2495
                else
2496
                  prev = &TREE_CHAIN (*prev);
2497
            }
2498
        }
2499
 
2500
      /* Now give a warning for all base functions without overriders,
2501
         as they are hidden.  */
2502
      while (base_fndecls)
2503
        {
2504
          /* Here we know it is a hider, and no overrider exists.  */
2505
          warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2506
          warning (OPT_Woverloaded_virtual, "  by %q+D", fns);
2507
          base_fndecls = TREE_CHAIN (base_fndecls);
2508
        }
2509
    }
2510
}
2511
 
2512
/* Check for things that are invalid.  There are probably plenty of other
2513
   things we should check for also.  */
2514
 
2515
static void
2516
finish_struct_anon (tree t)
2517
{
2518
  tree field;
2519
 
2520
  for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2521
    {
2522
      if (TREE_STATIC (field))
2523
        continue;
2524
      if (TREE_CODE (field) != FIELD_DECL)
2525
        continue;
2526
 
2527
      if (DECL_NAME (field) == NULL_TREE
2528
          && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2529
        {
2530
          bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2531
          tree elt = TYPE_FIELDS (TREE_TYPE (field));
2532
          for (; elt; elt = TREE_CHAIN (elt))
2533
            {
2534
              /* We're generally only interested in entities the user
2535
                 declared, but we also find nested classes by noticing
2536
                 the TYPE_DECL that we create implicitly.  You're
2537
                 allowed to put one anonymous union inside another,
2538
                 though, so we explicitly tolerate that.  We use
2539
                 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2540
                 we also allow unnamed types used for defining fields.  */
2541
              if (DECL_ARTIFICIAL (elt)
2542
                  && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2543
                      || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2544
                continue;
2545
 
2546
              if (TREE_CODE (elt) != FIELD_DECL)
2547
                {
2548
                  if (is_union)
2549
                    permerror (input_location, "%q+#D invalid; an anonymous union can "
2550
                               "only have non-static data members", elt);
2551
                  else
2552
                    permerror (input_location, "%q+#D invalid; an anonymous struct can "
2553
                               "only have non-static data members", elt);
2554
                  continue;
2555
                }
2556
 
2557
              if (TREE_PRIVATE (elt))
2558
                {
2559
                  if (is_union)
2560
                    permerror (input_location, "private member %q+#D in anonymous union", elt);
2561
                  else
2562
                    permerror (input_location, "private member %q+#D in anonymous struct", elt);
2563
                }
2564
              else if (TREE_PROTECTED (elt))
2565
                {
2566
                  if (is_union)
2567
                    permerror (input_location, "protected member %q+#D in anonymous union", elt);
2568
                  else
2569
                    permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2570
                }
2571
 
2572
              TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2573
              TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2574
            }
2575
        }
2576
    }
2577
}
2578
 
2579
/* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2580
   will be used later during class template instantiation.
2581
   When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2582
   a non-static member data (FIELD_DECL), a member function
2583
   (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2584
   a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2585
   When FRIEND_P is nonzero, T is either a friend class
2586
   (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2587
   (FUNCTION_DECL, TEMPLATE_DECL).  */
2588
 
2589
void
2590
maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2591
{
2592
  /* Save some memory by not creating TREE_LIST if TYPE is not template.  */
2593
  if (CLASSTYPE_TEMPLATE_INFO (type))
2594
    CLASSTYPE_DECL_LIST (type)
2595
      = tree_cons (friend_p ? NULL_TREE : type,
2596
                   t, CLASSTYPE_DECL_LIST (type));
2597
}
2598
 
2599
/* Create default constructors, assignment operators, and so forth for
2600
   the type indicated by T, if they are needed.  CANT_HAVE_CONST_CTOR,
2601
   and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2602
   the class cannot have a default constructor, copy constructor
2603
   taking a const reference argument, or an assignment operator taking
2604
   a const reference, respectively.  */
2605
 
2606
static void
2607
add_implicitly_declared_members (tree t,
2608
                                 int cant_have_const_cctor,
2609
                                 int cant_have_const_assignment)
2610
{
2611
  /* Destructor.  */
2612
  if (!CLASSTYPE_DESTRUCTORS (t))
2613
    {
2614
      /* In general, we create destructors lazily.  */
2615
      CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2616
      /* However, if the implicit destructor is non-trivial
2617
         destructor, we sometimes have to create it at this point.  */
2618
      if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2619
        {
2620
          bool lazy_p = true;
2621
 
2622
          if (TYPE_FOR_JAVA (t))
2623
            /* If this a Java class, any non-trivial destructor is
2624
               invalid, even if compiler-generated.  Therefore, if the
2625
               destructor is non-trivial we create it now.  */
2626
            lazy_p = false;
2627
          else
2628
            {
2629
              tree binfo;
2630
              tree base_binfo;
2631
              int ix;
2632
 
2633
              /* If the implicit destructor will be virtual, then we must
2634
                 generate it now because (unfortunately) we do not
2635
                 generate virtual tables lazily.  */
2636
              binfo = TYPE_BINFO (t);
2637
              for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2638
                {
2639
                  tree base_type;
2640
                  tree dtor;
2641
 
2642
                  base_type = BINFO_TYPE (base_binfo);
2643
                  dtor = CLASSTYPE_DESTRUCTORS (base_type);
2644
                  if (dtor && DECL_VIRTUAL_P (dtor))
2645
                    {
2646
                      lazy_p = false;
2647
                      break;
2648
                    }
2649
                }
2650
            }
2651
 
2652
          /* If we can't get away with being lazy, generate the destructor
2653
             now.  */
2654
          if (!lazy_p)
2655
            lazily_declare_fn (sfk_destructor, t);
2656
        }
2657
    }
2658
 
2659
  /* [class.ctor]
2660
 
2661
     If there is no user-declared constructor for a class, a default
2662
     constructor is implicitly declared.  */
2663
  if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2664
    {
2665
      TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2666
      CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2667
    }
2668
 
2669
  /* [class.ctor]
2670
 
2671
     If a class definition does not explicitly declare a copy
2672
     constructor, one is declared implicitly.  */
2673
  if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2674
    {
2675
      TYPE_HAS_INIT_REF (t) = 1;
2676
      TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2677
      CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2678
    }
2679
 
2680
  /* Currently only lambdas get a lazy move ctor, but N2987 adds them for
2681
     other classes.  */
2682
  if (LAMBDA_TYPE_P (t))
2683
    CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2684
 
2685
  /* If there is no assignment operator, one will be created if and
2686
     when it is needed.  For now, just record whether or not the type
2687
     of the parameter to the assignment operator will be a const or
2688
     non-const reference.  */
2689
  if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2690
    {
2691
      TYPE_HAS_ASSIGN_REF (t) = 1;
2692
      TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2693
      CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2694
    }
2695
}
2696
 
2697
/* Subroutine of finish_struct_1.  Recursively count the number of fields
2698
   in TYPE, including anonymous union members.  */
2699
 
2700
static int
2701
count_fields (tree fields)
2702
{
2703
  tree x;
2704
  int n_fields = 0;
2705
  for (x = fields; x; x = TREE_CHAIN (x))
2706
    {
2707
      if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2708
        n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2709
      else
2710
        n_fields += 1;
2711
    }
2712
  return n_fields;
2713
}
2714
 
2715
/* Subroutine of finish_struct_1.  Recursively add all the fields in the
2716
   TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX.  */
2717
 
2718
static int
2719
add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2720
{
2721
  tree x;
2722
  for (x = fields; x; x = TREE_CHAIN (x))
2723
    {
2724
      if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2725
        idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2726
      else
2727
        field_vec->elts[idx++] = x;
2728
    }
2729
  return idx;
2730
}
2731
 
2732
/* FIELD is a bit-field.  We are finishing the processing for its
2733
   enclosing type.  Issue any appropriate messages and set appropriate
2734
   flags.  Returns false if an error has been diagnosed.  */
2735
 
2736
static bool
2737
check_bitfield_decl (tree field)
2738
{
2739
  tree type = TREE_TYPE (field);
2740
  tree w;
2741
 
2742
  /* Extract the declared width of the bitfield, which has been
2743
     temporarily stashed in DECL_INITIAL.  */
2744
  w = DECL_INITIAL (field);
2745
  gcc_assert (w != NULL_TREE);
2746
  /* Remove the bit-field width indicator so that the rest of the
2747
     compiler does not treat that value as an initializer.  */
2748
  DECL_INITIAL (field) = NULL_TREE;
2749
 
2750
  /* Detect invalid bit-field type.  */
2751
  if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2752
    {
2753
      error ("bit-field %q+#D with non-integral type", field);
2754
      w = error_mark_node;
2755
    }
2756
  else
2757
    {
2758
      /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs.  */
2759
      STRIP_NOPS (w);
2760
 
2761
      /* detect invalid field size.  */
2762
      w = integral_constant_value (w);
2763
 
2764
      if (TREE_CODE (w) != INTEGER_CST)
2765
        {
2766
          error ("bit-field %q+D width not an integer constant", field);
2767
          w = error_mark_node;
2768
        }
2769
      else if (tree_int_cst_sgn (w) < 0)
2770
        {
2771
          error ("negative width in bit-field %q+D", field);
2772
          w = error_mark_node;
2773
        }
2774
      else if (integer_zerop (w) && DECL_NAME (field) != 0)
2775
        {
2776
          error ("zero width for bit-field %q+D", field);
2777
          w = error_mark_node;
2778
        }
2779
      else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2780
               && TREE_CODE (type) != ENUMERAL_TYPE
2781
               && TREE_CODE (type) != BOOLEAN_TYPE)
2782
        warning (0, "width of %q+D exceeds its type", field);
2783
      else if (TREE_CODE (type) == ENUMERAL_TYPE
2784
               && (0 > compare_tree_int (w,
2785
                                         tree_int_cst_min_precision
2786
                                         (TYPE_MIN_VALUE (type),
2787
                                          TYPE_UNSIGNED (type)))
2788
                   ||  0 > compare_tree_int (w,
2789
                                             tree_int_cst_min_precision
2790
                                             (TYPE_MAX_VALUE (type),
2791
                                              TYPE_UNSIGNED (type)))))
2792
        warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2793
    }
2794
 
2795
  if (w != error_mark_node)
2796
    {
2797
      DECL_SIZE (field) = convert (bitsizetype, w);
2798
      DECL_BIT_FIELD (field) = 1;
2799
      return true;
2800
    }
2801
  else
2802
    {
2803
      /* Non-bit-fields are aligned for their type.  */
2804
      DECL_BIT_FIELD (field) = 0;
2805
      CLEAR_DECL_C_BIT_FIELD (field);
2806
      return false;
2807
    }
2808
}
2809
 
2810
/* FIELD is a non bit-field.  We are finishing the processing for its
2811
   enclosing type T.  Issue any appropriate messages and set appropriate
2812
   flags.  */
2813
 
2814
static void
2815
check_field_decl (tree field,
2816
                  tree t,
2817
                  int* cant_have_const_ctor,
2818
                  int* no_const_asn_ref,
2819
                  int* any_default_members)
2820
{
2821
  tree type = strip_array_types (TREE_TYPE (field));
2822
 
2823
  /* An anonymous union cannot contain any fields which would change
2824
     the settings of CANT_HAVE_CONST_CTOR and friends.  */
2825
  if (ANON_UNION_TYPE_P (type))
2826
    ;
2827
  /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2828
     structs.  So, we recurse through their fields here.  */
2829
  else if (ANON_AGGR_TYPE_P (type))
2830
    {
2831
      tree fields;
2832
 
2833
      for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2834
        if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2835
          check_field_decl (fields, t, cant_have_const_ctor,
2836
                            no_const_asn_ref, any_default_members);
2837
    }
2838
  /* Check members with class type for constructors, destructors,
2839
     etc.  */
2840
  else if (CLASS_TYPE_P (type))
2841
    {
2842
      /* Never let anything with uninheritable virtuals
2843
         make it through without complaint.  */
2844
      abstract_virtuals_error (field, type);
2845
 
2846
      if (TREE_CODE (t) == UNION_TYPE)
2847
        {
2848
          if (TYPE_NEEDS_CONSTRUCTING (type))
2849
            error ("member %q+#D with constructor not allowed in union",
2850
                   field);
2851
          if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2852
            error ("member %q+#D with destructor not allowed in union", field);
2853
          if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2854
            error ("member %q+#D with copy assignment operator not allowed in union",
2855
                   field);
2856
        }
2857
      else
2858
        {
2859
          TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2860
          TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2861
            |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2862
          TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2863
          TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2864
          TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2865
        }
2866
 
2867
      if (!TYPE_HAS_CONST_INIT_REF (type))
2868
        *cant_have_const_ctor = 1;
2869
 
2870
      if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2871
        *no_const_asn_ref = 1;
2872
    }
2873
  if (DECL_INITIAL (field) != NULL_TREE)
2874
    {
2875
      /* `build_class_init_list' does not recognize
2876
         non-FIELD_DECLs.  */
2877
      if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2878
        error ("multiple fields in union %qT initialized", t);
2879
      *any_default_members = 1;
2880
    }
2881
}
2882
 
2883
/* Check the data members (both static and non-static), class-scoped
2884
   typedefs, etc., appearing in the declaration of T.  Issue
2885
   appropriate diagnostics.  Sets ACCESS_DECLS to a list (in
2886
   declaration order) of access declarations; each TREE_VALUE in this
2887
   list is a USING_DECL.
2888
 
2889
   In addition, set the following flags:
2890
 
2891
     EMPTY_P
2892
       The class is empty, i.e., contains no non-static data members.
2893
 
2894
     CANT_HAVE_CONST_CTOR_P
2895
       This class cannot have an implicitly generated copy constructor
2896
       taking a const reference.
2897
 
2898
     CANT_HAVE_CONST_ASN_REF
2899
       This class cannot have an implicitly generated assignment
2900
       operator taking a const reference.
2901
 
2902
   All of these flags should be initialized before calling this
2903
   function.
2904
 
2905
   Returns a pointer to the end of the TYPE_FIELDs chain; additional
2906
   fields can be added by adding to this chain.  */
2907
 
2908
static void
2909
check_field_decls (tree t, tree *access_decls,
2910
                   int *cant_have_const_ctor_p,
2911
                   int *no_const_asn_ref_p)
2912
{
2913
  tree *field;
2914
  tree *next;
2915
  bool has_pointers;
2916
  int any_default_members;
2917
  int cant_pack = 0;
2918
  int field_access = -1;
2919
 
2920
  /* Assume there are no access declarations.  */
2921
  *access_decls = NULL_TREE;
2922
  /* Assume this class has no pointer members.  */
2923
  has_pointers = false;
2924
  /* Assume none of the members of this class have default
2925
     initializations.  */
2926
  any_default_members = 0;
2927
 
2928
  for (field = &TYPE_FIELDS (t); *field; field = next)
2929
    {
2930
      tree x = *field;
2931
      tree type = TREE_TYPE (x);
2932
      int this_field_access;
2933
 
2934
      next = &TREE_CHAIN (x);
2935
 
2936
      if (TREE_CODE (x) == USING_DECL)
2937
        {
2938
          /* Prune the access declaration from the list of fields.  */
2939
          *field = TREE_CHAIN (x);
2940
 
2941
          /* Save the access declarations for our caller.  */
2942
          *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2943
 
2944
          /* Since we've reset *FIELD there's no reason to skip to the
2945
             next field.  */
2946
          next = field;
2947
          continue;
2948
        }
2949
 
2950
      if (TREE_CODE (x) == TYPE_DECL
2951
          || TREE_CODE (x) == TEMPLATE_DECL)
2952
        continue;
2953
 
2954
      /* If we've gotten this far, it's a data member, possibly static,
2955
         or an enumerator.  */
2956
      DECL_CONTEXT (x) = t;
2957
 
2958
      /* When this goes into scope, it will be a non-local reference.  */
2959
      DECL_NONLOCAL (x) = 1;
2960
 
2961
      if (TREE_CODE (t) == UNION_TYPE)
2962
        {
2963
          /* [class.union]
2964
 
2965
             If a union contains a static data member, or a member of
2966
             reference type, the program is ill-formed.  */
2967
          if (TREE_CODE (x) == VAR_DECL)
2968
            {
2969
              error ("%q+D may not be static because it is a member of a union", x);
2970
              continue;
2971
            }
2972
          if (TREE_CODE (type) == REFERENCE_TYPE)
2973
            {
2974
              error ("%q+D may not have reference type %qT because"
2975
                     " it is a member of a union",
2976
                     x, type);
2977
              continue;
2978
            }
2979
        }
2980
 
2981
      /* Perform error checking that did not get done in
2982
         grokdeclarator.  */
2983
      if (TREE_CODE (type) == FUNCTION_TYPE)
2984
        {
2985
          error ("field %q+D invalidly declared function type", x);
2986
          type = build_pointer_type (type);
2987
          TREE_TYPE (x) = type;
2988
        }
2989
      else if (TREE_CODE (type) == METHOD_TYPE)
2990
        {
2991
          error ("field %q+D invalidly declared method type", x);
2992
          type = build_pointer_type (type);
2993
          TREE_TYPE (x) = type;
2994
        }
2995
 
2996
      if (type == error_mark_node)
2997
        continue;
2998
 
2999
      if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3000
        continue;
3001
 
3002
      /* Now it can only be a FIELD_DECL.  */
3003
 
3004
      if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3005
        CLASSTYPE_NON_AGGREGATE (t) = 1;
3006
 
3007
      /* A standard-layout class is a class that:
3008
         ...
3009
         has the same access control (Clause 11) for all non-static data members,
3010
         ...  */
3011
      this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3012
      if (field_access == -1)
3013
        field_access = this_field_access;
3014
      else if (this_field_access != field_access)
3015
        CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3016
 
3017
      /* If this is of reference type, check if it needs an init.  */
3018
      if (TREE_CODE (type) == REFERENCE_TYPE)
3019
        {
3020
          CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3021
          CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3022
          if (DECL_INITIAL (x) == NULL_TREE)
3023
            SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3024
 
3025
          /* ARM $12.6.2: [A member initializer list] (or, for an
3026
             aggregate, initialization by a brace-enclosed list) is the
3027
             only way to initialize nonstatic const and reference
3028
             members.  */
3029
          TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3030
        }
3031
 
3032
      type = strip_array_types (type);
3033
 
3034
      if (TYPE_PACKED (t))
3035
        {
3036
          if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3037
            {
3038
              warning
3039
                (0,
3040
                 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3041
                 x);
3042
              cant_pack = 1;
3043
            }
3044
          else if (DECL_C_BIT_FIELD (x)
3045
                   || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3046
            DECL_PACKED (x) = 1;
3047
        }
3048
 
3049
      if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3050
        /* We don't treat zero-width bitfields as making a class
3051
           non-empty.  */
3052
        ;
3053
      else
3054
        {
3055
          /* The class is non-empty.  */
3056
          CLASSTYPE_EMPTY_P (t) = 0;
3057
          /* The class is not even nearly empty.  */
3058
          CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3059
          /* If one of the data members contains an empty class,
3060
             so does T.  */
3061
          if (CLASS_TYPE_P (type)
3062
              && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3063
            CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3064
        }
3065
 
3066
      /* This is used by -Weffc++ (see below). Warn only for pointers
3067
         to members which might hold dynamic memory. So do not warn
3068
         for pointers to functions or pointers to members.  */
3069
      if (TYPE_PTR_P (type)
3070
          && !TYPE_PTRFN_P (type)
3071
          && !TYPE_PTR_TO_MEMBER_P (type))
3072
        has_pointers = true;
3073
 
3074
      if (CLASS_TYPE_P (type))
3075
        {
3076
          if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3077
            SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3078
          if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3079
            SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3080
        }
3081
 
3082
      if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3083
        CLASSTYPE_HAS_MUTABLE (t) = 1;
3084
 
3085
      if (! layout_pod_type_p (type))
3086
        /* DR 148 now allows pointers to members (which are POD themselves),
3087
           to be allowed in POD structs.  */
3088
        CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3089
 
3090
      if (!std_layout_type_p (type))
3091
        CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3092
 
3093
      if (! zero_init_p (type))
3094
        CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3095
 
3096
      /* If any field is const, the structure type is pseudo-const.  */
3097
      if (CP_TYPE_CONST_P (type))
3098
        {
3099
          C_TYPE_FIELDS_READONLY (t) = 1;
3100
          if (DECL_INITIAL (x) == NULL_TREE)
3101
            SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3102
 
3103
          /* ARM $12.6.2: [A member initializer list] (or, for an
3104
             aggregate, initialization by a brace-enclosed list) is the
3105
             only way to initialize nonstatic const and reference
3106
             members.  */
3107
          TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3108
        }
3109
      /* A field that is pseudo-const makes the structure likewise.  */
3110
      else if (CLASS_TYPE_P (type))
3111
        {
3112
          C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3113
          SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3114
            CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3115
            | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3116
        }
3117
 
3118
      /* Core issue 80: A nonstatic data member is required to have a
3119
         different name from the class iff the class has a
3120
         user-declared constructor.  */
3121
      if (constructor_name_p (DECL_NAME (x), t)
3122
          && TYPE_HAS_USER_CONSTRUCTOR (t))
3123
        permerror (input_location, "field %q+#D with same name as class", x);
3124
 
3125
      /* We set DECL_C_BIT_FIELD in grokbitfield.
3126
         If the type and width are valid, we'll also set DECL_BIT_FIELD.  */
3127
      if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3128
        check_field_decl (x, t,
3129
                          cant_have_const_ctor_p,
3130
                          no_const_asn_ref_p,
3131
                          &any_default_members);
3132
    }
3133
 
3134
  /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3135
     it should also define a copy constructor and an assignment operator to
3136
     implement the correct copy semantic (deep vs shallow, etc.). As it is
3137
     not feasible to check whether the constructors do allocate dynamic memory
3138
     and store it within members, we approximate the warning like this:
3139
 
3140
     -- Warn only if there are members which are pointers
3141
     -- Warn only if there is a non-trivial constructor (otherwise,
3142
        there cannot be memory allocated).
3143
     -- Warn only if there is a non-trivial destructor. We assume that the
3144
        user at least implemented the cleanup correctly, and a destructor
3145
        is needed to free dynamic memory.
3146
 
3147
     This seems enough for practical purposes.  */
3148
  if (warn_ecpp
3149
      && has_pointers
3150
      && TYPE_HAS_USER_CONSTRUCTOR (t)
3151
      && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3152
      && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3153
    {
3154
      warning (OPT_Weffc__, "%q#T has pointer data members", t);
3155
 
3156
      if (! TYPE_HAS_INIT_REF (t))
3157
        {
3158
          warning (OPT_Weffc__,
3159
                   "  but does not override %<%T(const %T&)%>", t, t);
3160
          if (!TYPE_HAS_ASSIGN_REF (t))
3161
            warning (OPT_Weffc__, "  or %<operator=(const %T&)%>", t);
3162
        }
3163
      else if (! TYPE_HAS_ASSIGN_REF (t))
3164
        warning (OPT_Weffc__,
3165
                 "  but does not override %<operator=(const %T&)%>", t);
3166
    }
3167
 
3168
  /* If any of the fields couldn't be packed, unset TYPE_PACKED.  */
3169
  if (cant_pack)
3170
    TYPE_PACKED (t) = 0;
3171
 
3172
  /* Check anonymous struct/anonymous union fields.  */
3173
  finish_struct_anon (t);
3174
 
3175
  /* We've built up the list of access declarations in reverse order.
3176
     Fix that now.  */
3177
  *access_decls = nreverse (*access_decls);
3178
}
3179
 
3180
/* If TYPE is an empty class type, records its OFFSET in the table of
3181
   OFFSETS.  */
3182
 
3183
static int
3184
record_subobject_offset (tree type, tree offset, splay_tree offsets)
3185
{
3186
  splay_tree_node n;
3187
 
3188
  if (!is_empty_class (type))
3189
    return 0;
3190
 
3191
  /* Record the location of this empty object in OFFSETS.  */
3192
  n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3193
  if (!n)
3194
    n = splay_tree_insert (offsets,
3195
                           (splay_tree_key) offset,
3196
                           (splay_tree_value) NULL_TREE);
3197
  n->value = ((splay_tree_value)
3198
              tree_cons (NULL_TREE,
3199
                         type,
3200
                         (tree) n->value));
3201
 
3202
  return 0;
3203
}
3204
 
3205
/* Returns nonzero if TYPE is an empty class type and there is
3206
   already an entry in OFFSETS for the same TYPE as the same OFFSET.  */
3207
 
3208
static int
3209
check_subobject_offset (tree type, tree offset, splay_tree offsets)
3210
{
3211
  splay_tree_node n;
3212
  tree t;
3213
 
3214
  if (!is_empty_class (type))
3215
    return 0;
3216
 
3217
  /* Record the location of this empty object in OFFSETS.  */
3218
  n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3219
  if (!n)
3220
    return 0;
3221
 
3222
  for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3223
    if (same_type_p (TREE_VALUE (t), type))
3224
      return 1;
3225
 
3226
  return 0;
3227
}
3228
 
3229
/* Walk through all the subobjects of TYPE (located at OFFSET).  Call
3230
   F for every subobject, passing it the type, offset, and table of
3231
   OFFSETS.  If VBASES_P is one, then virtual non-primary bases should
3232
   be traversed.
3233
 
3234
   If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3235
   than MAX_OFFSET will not be walked.
3236
 
3237
   If F returns a nonzero value, the traversal ceases, and that value
3238
   is returned.  Otherwise, returns zero.  */
3239
 
3240
static int
3241
walk_subobject_offsets (tree type,
3242
                        subobject_offset_fn f,
3243
                        tree offset,
3244
                        splay_tree offsets,
3245
                        tree max_offset,
3246
                        int vbases_p)
3247
{
3248
  int r = 0;
3249
  tree type_binfo = NULL_TREE;
3250
 
3251
  /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3252
     stop.  */
3253
  if (max_offset && INT_CST_LT (max_offset, offset))
3254
    return 0;
3255
 
3256
  if (type == error_mark_node)
3257
    return 0;
3258
 
3259
  if (!TYPE_P (type))
3260
    {
3261
      if (abi_version_at_least (2))
3262
        type_binfo = type;
3263
      type = BINFO_TYPE (type);
3264
    }
3265
 
3266
  if (CLASS_TYPE_P (type))
3267
    {
3268
      tree field;
3269
      tree binfo;
3270
      int i;
3271
 
3272
      /* Avoid recursing into objects that are not interesting.  */
3273
      if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3274
        return 0;
3275
 
3276
      /* Record the location of TYPE.  */
3277
      r = (*f) (type, offset, offsets);
3278
      if (r)
3279
        return r;
3280
 
3281
      /* Iterate through the direct base classes of TYPE.  */
3282
      if (!type_binfo)
3283
        type_binfo = TYPE_BINFO (type);
3284
      for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3285
        {
3286
          tree binfo_offset;
3287
 
3288
          if (abi_version_at_least (2)
3289
              && BINFO_VIRTUAL_P (binfo))
3290
            continue;
3291
 
3292
          if (!vbases_p
3293
              && BINFO_VIRTUAL_P (binfo)
3294
              && !BINFO_PRIMARY_P (binfo))
3295
            continue;
3296
 
3297
          if (!abi_version_at_least (2))
3298
            binfo_offset = size_binop (PLUS_EXPR,
3299
                                       offset,
3300
                                       BINFO_OFFSET (binfo));
3301
          else
3302
            {
3303
              tree orig_binfo;
3304
              /* We cannot rely on BINFO_OFFSET being set for the base
3305
                 class yet, but the offsets for direct non-virtual
3306
                 bases can be calculated by going back to the TYPE.  */
3307
              orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3308
              binfo_offset = size_binop (PLUS_EXPR,
3309
                                         offset,
3310
                                         BINFO_OFFSET (orig_binfo));
3311
            }
3312
 
3313
          r = walk_subobject_offsets (binfo,
3314
                                      f,
3315
                                      binfo_offset,
3316
                                      offsets,
3317
                                      max_offset,
3318
                                      (abi_version_at_least (2)
3319
                                       ? /*vbases_p=*/0 : vbases_p));
3320
          if (r)
3321
            return r;
3322
        }
3323
 
3324
      if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3325
        {
3326
          unsigned ix;
3327
          VEC(tree,gc) *vbases;
3328
 
3329
          /* Iterate through the virtual base classes of TYPE.  In G++
3330
             3.2, we included virtual bases in the direct base class
3331
             loop above, which results in incorrect results; the
3332
             correct offsets for virtual bases are only known when
3333
             working with the most derived type.  */
3334
          if (vbases_p)
3335
            for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3336
                 VEC_iterate (tree, vbases, ix, binfo); ix++)
3337
              {
3338
                r = walk_subobject_offsets (binfo,
3339
                                            f,
3340
                                            size_binop (PLUS_EXPR,
3341
                                                        offset,
3342
                                                        BINFO_OFFSET (binfo)),
3343
                                            offsets,
3344
                                            max_offset,
3345
                                            /*vbases_p=*/0);
3346
                if (r)
3347
                  return r;
3348
              }
3349
          else
3350
            {
3351
              /* We still have to walk the primary base, if it is
3352
                 virtual.  (If it is non-virtual, then it was walked
3353
                 above.)  */
3354
              tree vbase = get_primary_binfo (type_binfo);
3355
 
3356
              if (vbase && BINFO_VIRTUAL_P (vbase)
3357
                  && BINFO_PRIMARY_P (vbase)
3358
                  && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3359
                {
3360
                  r = (walk_subobject_offsets
3361
                       (vbase, f, offset,
3362
                        offsets, max_offset, /*vbases_p=*/0));
3363
                  if (r)
3364
                    return r;
3365
                }
3366
            }
3367
        }
3368
 
3369
      /* Iterate through the fields of TYPE.  */
3370
      for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3371
        if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3372
          {
3373
            tree field_offset;
3374
 
3375
            if (abi_version_at_least (2))
3376
              field_offset = byte_position (field);
3377
            else
3378
              /* In G++ 3.2, DECL_FIELD_OFFSET was used.  */
3379
              field_offset = DECL_FIELD_OFFSET (field);
3380
 
3381
            r = walk_subobject_offsets (TREE_TYPE (field),
3382
                                        f,
3383
                                        size_binop (PLUS_EXPR,
3384
                                                    offset,
3385
                                                    field_offset),
3386
                                        offsets,
3387
                                        max_offset,
3388
                                        /*vbases_p=*/1);
3389
            if (r)
3390
              return r;
3391
          }
3392
    }
3393
  else if (TREE_CODE (type) == ARRAY_TYPE)
3394
    {
3395
      tree element_type = strip_array_types (type);
3396
      tree domain = TYPE_DOMAIN (type);
3397
      tree index;
3398
 
3399
      /* Avoid recursing into objects that are not interesting.  */
3400
      if (!CLASS_TYPE_P (element_type)
3401
          || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3402
        return 0;
3403
 
3404
      /* Step through each of the elements in the array.  */
3405
      for (index = size_zero_node;
3406
           /* G++ 3.2 had an off-by-one error here.  */
3407
           (abi_version_at_least (2)
3408
            ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3409
            : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3410
           index = size_binop (PLUS_EXPR, index, size_one_node))
3411
        {
3412
          r = walk_subobject_offsets (TREE_TYPE (type),
3413
                                      f,
3414
                                      offset,
3415
                                      offsets,
3416
                                      max_offset,
3417
                                      /*vbases_p=*/1);
3418
          if (r)
3419
            return r;
3420
          offset = size_binop (PLUS_EXPR, offset,
3421
                               TYPE_SIZE_UNIT (TREE_TYPE (type)));
3422
          /* If this new OFFSET is bigger than the MAX_OFFSET, then
3423
             there's no point in iterating through the remaining
3424
             elements of the array.  */
3425
          if (max_offset && INT_CST_LT (max_offset, offset))
3426
            break;
3427
        }
3428
    }
3429
 
3430
  return 0;
3431
}
3432
 
3433
/* Record all of the empty subobjects of TYPE (either a type or a
3434
   binfo).  If IS_DATA_MEMBER is true, then a non-static data member
3435
   is being placed at OFFSET; otherwise, it is a base class that is
3436
   being placed at OFFSET.  */
3437
 
3438
static void
3439
record_subobject_offsets (tree type,
3440
                          tree offset,
3441
                          splay_tree offsets,
3442
                          bool is_data_member)
3443
{
3444
  tree max_offset;
3445
  /* If recording subobjects for a non-static data member or a
3446
     non-empty base class , we do not need to record offsets beyond
3447
     the size of the biggest empty class.  Additional data members
3448
     will go at the end of the class.  Additional base classes will go
3449
     either at offset zero (if empty, in which case they cannot
3450
     overlap with offsets past the size of the biggest empty class) or
3451
     at the end of the class.
3452
 
3453
     However, if we are placing an empty base class, then we must record
3454
     all offsets, as either the empty class is at offset zero (where
3455
     other empty classes might later be placed) or at the end of the
3456
     class (where other objects might then be placed, so other empty
3457
     subobjects might later overlap).  */
3458
  if (is_data_member
3459
      || !is_empty_class (BINFO_TYPE (type)))
3460
    max_offset = sizeof_biggest_empty_class;
3461
  else
3462
    max_offset = NULL_TREE;
3463
  walk_subobject_offsets (type, record_subobject_offset, offset,
3464
                          offsets, max_offset, is_data_member);
3465
}
3466
 
3467
/* Returns nonzero if any of the empty subobjects of TYPE (located at
3468
   OFFSET) conflict with entries in OFFSETS.  If VBASES_P is nonzero,
3469
   virtual bases of TYPE are examined.  */
3470
 
3471
static int
3472
layout_conflict_p (tree type,
3473
                   tree offset,
3474
                   splay_tree offsets,
3475
                   int vbases_p)
3476
{
3477
  splay_tree_node max_node;
3478
 
3479
  /* Get the node in OFFSETS that indicates the maximum offset where
3480
     an empty subobject is located.  */
3481
  max_node = splay_tree_max (offsets);
3482
  /* If there aren't any empty subobjects, then there's no point in
3483
     performing this check.  */
3484
  if (!max_node)
3485
    return 0;
3486
 
3487
  return walk_subobject_offsets (type, check_subobject_offset, offset,
3488
                                 offsets, (tree) (max_node->key),
3489
                                 vbases_p);
3490
}
3491
 
3492
/* DECL is a FIELD_DECL corresponding either to a base subobject of a
3493
   non-static data member of the type indicated by RLI.  BINFO is the
3494
   binfo corresponding to the base subobject, OFFSETS maps offsets to
3495
   types already located at those offsets.  This function determines
3496
   the position of the DECL.  */
3497
 
3498
static void
3499
layout_nonempty_base_or_field (record_layout_info rli,
3500
                               tree decl,
3501
                               tree binfo,
3502
                               splay_tree offsets)
3503
{
3504
  tree offset = NULL_TREE;
3505
  bool field_p;
3506
  tree type;
3507
 
3508
  if (binfo)
3509
    {
3510
      /* For the purposes of determining layout conflicts, we want to
3511
         use the class type of BINFO; TREE_TYPE (DECL) will be the
3512
         CLASSTYPE_AS_BASE version, which does not contain entries for
3513
         zero-sized bases.  */
3514
      type = TREE_TYPE (binfo);
3515
      field_p = false;
3516
    }
3517
  else
3518
    {
3519
      type = TREE_TYPE (decl);
3520
      field_p = true;
3521
    }
3522
 
3523
  /* Try to place the field.  It may take more than one try if we have
3524
     a hard time placing the field without putting two objects of the
3525
     same type at the same address.  */
3526
  while (1)
3527
    {
3528
      struct record_layout_info_s old_rli = *rli;
3529
 
3530
      /* Place this field.  */
3531
      place_field (rli, decl);
3532
      offset = byte_position (decl);
3533
 
3534
      /* We have to check to see whether or not there is already
3535
         something of the same type at the offset we're about to use.
3536
         For example, consider:
3537
 
3538
           struct S {};
3539
           struct T : public S { int i; };
3540
           struct U : public S, public T {};
3541
 
3542
         Here, we put S at offset zero in U.  Then, we can't put T at
3543
         offset zero -- its S component would be at the same address
3544
         as the S we already allocated.  So, we have to skip ahead.
3545
         Since all data members, including those whose type is an
3546
         empty class, have nonzero size, any overlap can happen only
3547
         with a direct or indirect base-class -- it can't happen with
3548
         a data member.  */
3549
      /* In a union, overlap is permitted; all members are placed at
3550
         offset zero.  */
3551
      if (TREE_CODE (rli->t) == UNION_TYPE)
3552
        break;
3553
      /* G++ 3.2 did not check for overlaps when placing a non-empty
3554
         virtual base.  */
3555
      if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3556
        break;
3557
      if (layout_conflict_p (field_p ? type : binfo, offset,
3558
                             offsets, field_p))
3559
        {
3560
          /* Strip off the size allocated to this field.  That puts us
3561
             at the first place we could have put the field with
3562
             proper alignment.  */
3563
          *rli = old_rli;
3564
 
3565
          /* Bump up by the alignment required for the type.  */
3566
          rli->bitpos
3567
            = size_binop (PLUS_EXPR, rli->bitpos,
3568
                          bitsize_int (binfo
3569
                                       ? CLASSTYPE_ALIGN (type)
3570
                                       : TYPE_ALIGN (type)));
3571
          normalize_rli (rli);
3572
        }
3573
      else
3574
        /* There was no conflict.  We're done laying out this field.  */
3575
        break;
3576
    }
3577
 
3578
  /* Now that we know where it will be placed, update its
3579
     BINFO_OFFSET.  */
3580
  if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3581
    /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3582
       this point because their BINFO_OFFSET is copied from another
3583
       hierarchy.  Therefore, we may not need to add the entire
3584
       OFFSET.  */
3585
    propagate_binfo_offsets (binfo,
3586
                             size_diffop_loc (input_location,
3587
                                          convert (ssizetype, offset),
3588
                                          convert (ssizetype,
3589
                                                   BINFO_OFFSET (binfo))));
3590
}
3591
 
3592
/* Returns true if TYPE is empty and OFFSET is nonzero.  */
3593
 
3594
static int
3595
empty_base_at_nonzero_offset_p (tree type,
3596
                                tree offset,
3597
                                splay_tree offsets ATTRIBUTE_UNUSED)
3598
{
3599
  return is_empty_class (type) && !integer_zerop (offset);
3600
}
3601
 
3602
/* Layout the empty base BINFO.  EOC indicates the byte currently just
3603
   past the end of the class, and should be correctly aligned for a
3604
   class of the type indicated by BINFO; OFFSETS gives the offsets of
3605
   the empty bases allocated so far. T is the most derived
3606
   type.  Return nonzero iff we added it at the end.  */
3607
 
3608
static bool
3609
layout_empty_base (record_layout_info rli, tree binfo,
3610
                   tree eoc, splay_tree offsets)
3611
{
3612
  tree alignment;
3613
  tree basetype = BINFO_TYPE (binfo);
3614
  bool atend = false;
3615
 
3616
  /* This routine should only be used for empty classes.  */
3617
  gcc_assert (is_empty_class (basetype));
3618
  alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3619
 
3620
  if (!integer_zerop (BINFO_OFFSET (binfo)))
3621
    {
3622
      if (abi_version_at_least (2))
3623
        propagate_binfo_offsets
3624
          (binfo, size_diffop_loc (input_location,
3625
                               size_zero_node, BINFO_OFFSET (binfo)));
3626
      else
3627
        warning (OPT_Wabi,
3628
                 "offset of empty base %qT may not be ABI-compliant and may"
3629
                 "change in a future version of GCC",
3630
                 BINFO_TYPE (binfo));
3631
    }
3632
 
3633
  /* This is an empty base class.  We first try to put it at offset
3634
     zero.  */
3635
  if (layout_conflict_p (binfo,
3636
                         BINFO_OFFSET (binfo),
3637
                         offsets,
3638
                         /*vbases_p=*/0))
3639
    {
3640
      /* That didn't work.  Now, we move forward from the next
3641
         available spot in the class.  */
3642
      atend = true;
3643
      propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3644
      while (1)
3645
        {
3646
          if (!layout_conflict_p (binfo,
3647
                                  BINFO_OFFSET (binfo),
3648
                                  offsets,
3649
                                  /*vbases_p=*/0))
3650
            /* We finally found a spot where there's no overlap.  */
3651
            break;
3652
 
3653
          /* There's overlap here, too.  Bump along to the next spot.  */
3654
          propagate_binfo_offsets (binfo, alignment);
3655
        }
3656
    }
3657
 
3658
  if (CLASSTYPE_USER_ALIGN (basetype))
3659
    {
3660
      rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3661
      if (warn_packed)
3662
        rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3663
      TYPE_USER_ALIGN (rli->t) = 1;
3664
    }
3665
 
3666
  return atend;
3667
}
3668
 
3669
/* Layout the base given by BINFO in the class indicated by RLI.
3670
   *BASE_ALIGN is a running maximum of the alignments of
3671
   any base class.  OFFSETS gives the location of empty base
3672
   subobjects.  T is the most derived type.  Return nonzero if the new
3673
   object cannot be nearly-empty.  A new FIELD_DECL is inserted at
3674
   *NEXT_FIELD, unless BINFO is for an empty base class.
3675
 
3676
   Returns the location at which the next field should be inserted.  */
3677
 
3678
static tree *
3679
build_base_field (record_layout_info rli, tree binfo,
3680
                  splay_tree offsets, tree *next_field)
3681
{
3682
  tree t = rli->t;
3683
  tree basetype = BINFO_TYPE (binfo);
3684
 
3685
  if (!COMPLETE_TYPE_P (basetype))
3686
    /* This error is now reported in xref_tag, thus giving better
3687
       location information.  */
3688
    return next_field;
3689
 
3690
  /* Place the base class.  */
3691
  if (!is_empty_class (basetype))
3692
    {
3693
      tree decl;
3694
 
3695
      /* The containing class is non-empty because it has a non-empty
3696
         base class.  */
3697
      CLASSTYPE_EMPTY_P (t) = 0;
3698
 
3699
      /* Create the FIELD_DECL.  */
3700
      decl = build_decl (input_location,
3701
                         FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3702
      DECL_ARTIFICIAL (decl) = 1;
3703
      DECL_IGNORED_P (decl) = 1;
3704
      DECL_FIELD_CONTEXT (decl) = t;
3705
      if (CLASSTYPE_AS_BASE (basetype))
3706
        {
3707
          DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3708
          DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3709
          DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3710
          DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3711
          DECL_MODE (decl) = TYPE_MODE (basetype);
3712
          DECL_FIELD_IS_BASE (decl) = 1;
3713
 
3714
          /* Try to place the field.  It may take more than one try if we
3715
             have a hard time placing the field without putting two
3716
             objects of the same type at the same address.  */
3717
          layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3718
          /* Add the new FIELD_DECL to the list of fields for T.  */
3719
          TREE_CHAIN (decl) = *next_field;
3720
          *next_field = decl;
3721
          next_field = &TREE_CHAIN (decl);
3722
        }
3723
    }
3724
  else
3725
    {
3726
      tree eoc;
3727
      bool atend;
3728
 
3729
      /* On some platforms (ARM), even empty classes will not be
3730
         byte-aligned.  */
3731
      eoc = round_up_loc (input_location,
3732
                      rli_size_unit_so_far (rli),
3733
                      CLASSTYPE_ALIGN_UNIT (basetype));
3734
      atend = layout_empty_base (rli, binfo, eoc, offsets);
3735
      /* A nearly-empty class "has no proper base class that is empty,
3736
         not morally virtual, and at an offset other than zero."  */
3737
      if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3738
        {
3739
          if (atend)
3740
            CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3741
          /* The check above (used in G++ 3.2) is insufficient because
3742
             an empty class placed at offset zero might itself have an
3743
             empty base at a nonzero offset.  */
3744
          else if (walk_subobject_offsets (basetype,
3745
                                           empty_base_at_nonzero_offset_p,
3746
                                           size_zero_node,
3747
                                           /*offsets=*/NULL,
3748
                                           /*max_offset=*/NULL_TREE,
3749
                                           /*vbases_p=*/true))
3750
            {
3751
              if (abi_version_at_least (2))
3752
                CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3753
              else
3754
                warning (OPT_Wabi,
3755
                         "class %qT will be considered nearly empty in a "
3756
                         "future version of GCC", t);
3757
            }
3758
        }
3759
 
3760
      /* We do not create a FIELD_DECL for empty base classes because
3761
         it might overlap some other field.  We want to be able to
3762
         create CONSTRUCTORs for the class by iterating over the
3763
         FIELD_DECLs, and the back end does not handle overlapping
3764
         FIELD_DECLs.  */
3765
 
3766
      /* An empty virtual base causes a class to be non-empty
3767
         -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3768
         here because that was already done when the virtual table
3769
         pointer was created.  */
3770
    }
3771
 
3772
  /* Record the offsets of BINFO and its base subobjects.  */
3773
  record_subobject_offsets (binfo,
3774
                            BINFO_OFFSET (binfo),
3775
                            offsets,
3776
                            /*is_data_member=*/false);
3777
 
3778
  return next_field;
3779
}
3780
 
3781
/* Layout all of the non-virtual base classes.  Record empty
3782
   subobjects in OFFSETS.  T is the most derived type.  Return nonzero
3783
   if the type cannot be nearly empty.  The fields created
3784
   corresponding to the base classes will be inserted at
3785
   *NEXT_FIELD.  */
3786
 
3787
static void
3788
build_base_fields (record_layout_info rli,
3789
                   splay_tree offsets, tree *next_field)
3790
{
3791
  /* Chain to hold all the new FIELD_DECLs which stand in for base class
3792
     subobjects.  */
3793
  tree t = rli->t;
3794
  int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3795
  int i;
3796
 
3797
  /* The primary base class is always allocated first.  */
3798
  if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3799
    next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3800
                                   offsets, next_field);
3801
 
3802
  /* Now allocate the rest of the bases.  */
3803
  for (i = 0; i < n_baseclasses; ++i)
3804
    {
3805
      tree base_binfo;
3806
 
3807
      base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3808
 
3809
      /* The primary base was already allocated above, so we don't
3810
         need to allocate it again here.  */
3811
      if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3812
        continue;
3813
 
3814
      /* Virtual bases are added at the end (a primary virtual base
3815
         will have already been added).  */
3816
      if (BINFO_VIRTUAL_P (base_binfo))
3817
        continue;
3818
 
3819
      next_field = build_base_field (rli, base_binfo,
3820
                                     offsets, next_field);
3821
    }
3822
}
3823
 
3824
/* Go through the TYPE_METHODS of T issuing any appropriate
3825
   diagnostics, figuring out which methods override which other
3826
   methods, and so forth.  */
3827
 
3828
static void
3829
check_methods (tree t)
3830
{
3831
  tree x;
3832
 
3833
  for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3834
    {
3835
      check_for_override (x, t);
3836
      if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3837
        error ("initializer specified for non-virtual method %q+D", x);
3838
      /* The name of the field is the original field name
3839
         Save this in auxiliary field for later overloading.  */
3840
      if (DECL_VINDEX (x))
3841
        {
3842
          TYPE_POLYMORPHIC_P (t) = 1;
3843
          if (DECL_PURE_VIRTUAL_P (x))
3844
            VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3845
        }
3846
      /* All user-provided destructors are non-trivial.  */
3847
      if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3848
        TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3849
    }
3850
}
3851
 
3852
/* FN is a constructor or destructor.  Clone the declaration to create
3853
   a specialized in-charge or not-in-charge version, as indicated by
3854
   NAME.  */
3855
 
3856
static tree
3857
build_clone (tree fn, tree name)
3858
{
3859
  tree parms;
3860
  tree clone;
3861
 
3862
  /* Copy the function.  */
3863
  clone = copy_decl (fn);
3864
  /* Reset the function name.  */
3865
  DECL_NAME (clone) = name;
3866
  SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3867
  /* Remember where this function came from.  */
3868
  DECL_ABSTRACT_ORIGIN (clone) = fn;
3869
  /* Make it easy to find the CLONE given the FN.  */
3870
  TREE_CHAIN (clone) = TREE_CHAIN (fn);
3871
  TREE_CHAIN (fn) = clone;
3872
 
3873
  /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT.  */
3874
  if (TREE_CODE (clone) == TEMPLATE_DECL)
3875
    {
3876
      tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3877
      DECL_TEMPLATE_RESULT (clone) = result;
3878
      DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3879
      DECL_TI_TEMPLATE (result) = clone;
3880
      TREE_TYPE (clone) = TREE_TYPE (result);
3881
      return clone;
3882
    }
3883
 
3884
  DECL_CLONED_FUNCTION (clone) = fn;
3885
  /* There's no pending inline data for this function.  */
3886
  DECL_PENDING_INLINE_INFO (clone) = NULL;
3887
  DECL_PENDING_INLINE_P (clone) = 0;
3888
 
3889
  /* The base-class destructor is not virtual.  */
3890
  if (name == base_dtor_identifier)
3891
    {
3892
      DECL_VIRTUAL_P (clone) = 0;
3893
      if (TREE_CODE (clone) != TEMPLATE_DECL)
3894
        DECL_VINDEX (clone) = NULL_TREE;
3895
    }
3896
 
3897
  /* If there was an in-charge parameter, drop it from the function
3898
     type.  */
3899
  if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3900
    {
3901
      tree basetype;
3902
      tree parmtypes;
3903
      tree exceptions;
3904
 
3905
      exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3906
      basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3907
      parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3908
      /* Skip the `this' parameter.  */
3909
      parmtypes = TREE_CHAIN (parmtypes);
3910
      /* Skip the in-charge parameter.  */
3911
      parmtypes = TREE_CHAIN (parmtypes);
3912
      /* And the VTT parm, in a complete [cd]tor.  */
3913
      if (DECL_HAS_VTT_PARM_P (fn)
3914
          && ! DECL_NEEDS_VTT_PARM_P (clone))
3915
        parmtypes = TREE_CHAIN (parmtypes);
3916
       /* If this is subobject constructor or destructor, add the vtt
3917
         parameter.  */
3918
      TREE_TYPE (clone)
3919
        = build_method_type_directly (basetype,
3920
                                      TREE_TYPE (TREE_TYPE (clone)),
3921
                                      parmtypes);
3922
      if (exceptions)
3923
        TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3924
                                                     exceptions);
3925
      TREE_TYPE (clone)
3926
        = cp_build_type_attribute_variant (TREE_TYPE (clone),
3927
                                           TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3928
    }
3929
 
3930
  /* Copy the function parameters.  */
3931
  DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3932
  /* Remove the in-charge parameter.  */
3933
  if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3934
    {
3935
      TREE_CHAIN (DECL_ARGUMENTS (clone))
3936
        = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3937
      DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3938
    }
3939
  /* And the VTT parm, in a complete [cd]tor.  */
3940
  if (DECL_HAS_VTT_PARM_P (fn))
3941
    {
3942
      if (DECL_NEEDS_VTT_PARM_P (clone))
3943
        DECL_HAS_VTT_PARM_P (clone) = 1;
3944
      else
3945
        {
3946
          TREE_CHAIN (DECL_ARGUMENTS (clone))
3947
            = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3948
          DECL_HAS_VTT_PARM_P (clone) = 0;
3949
        }
3950
    }
3951
 
3952
  for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3953
    {
3954
      DECL_CONTEXT (parms) = clone;
3955
      cxx_dup_lang_specific_decl (parms);
3956
    }
3957
 
3958
  /* Create the RTL for this function.  */
3959
  SET_DECL_RTL (clone, NULL_RTX);
3960
  rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3961
 
3962
  if (pch_file)
3963
    note_decl_for_pch (clone);
3964
 
3965
  return clone;
3966
}
3967
 
3968
/* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
3969
   not invoke this function directly.
3970
 
3971
   For a non-thunk function, returns the address of the slot for storing
3972
   the function it is a clone of.  Otherwise returns NULL_TREE.
3973
 
3974
   If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
3975
   cloned_function is unset.  This is to support the separate
3976
   DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
3977
   on a template makes sense, but not the former.  */
3978
 
3979
tree *
3980
decl_cloned_function_p (const_tree decl, bool just_testing)
3981
{
3982
  tree *ptr;
3983
  if (just_testing)
3984
    decl = STRIP_TEMPLATE (decl);
3985
 
3986
  if (TREE_CODE (decl) != FUNCTION_DECL
3987
      || !DECL_LANG_SPECIFIC (decl)
3988
      || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
3989
    {
3990
#if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
3991
      if (!just_testing)
3992
        lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
3993
      else
3994
#endif
3995
        return NULL;
3996
    }
3997
 
3998
  ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
3999
  if (just_testing && *ptr == NULL_TREE)
4000
    return NULL;
4001
  else
4002
    return ptr;
4003
}
4004
 
4005
/* Produce declarations for all appropriate clones of FN.  If
4006
   UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4007
   CLASTYPE_METHOD_VEC as well.  */
4008
 
4009
void
4010
clone_function_decl (tree fn, int update_method_vec_p)
4011
{
4012
  tree clone;
4013
 
4014
  /* Avoid inappropriate cloning.  */
4015
  if (TREE_CHAIN (fn)
4016
      && DECL_CLONED_FUNCTION_P (TREE_CHAIN (fn)))
4017
    return;
4018
 
4019
  if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4020
    {
4021
      /* For each constructor, we need two variants: an in-charge version
4022
         and a not-in-charge version.  */
4023
      clone = build_clone (fn, complete_ctor_identifier);
4024
      if (update_method_vec_p)
4025
        add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4026
      clone = build_clone (fn, base_ctor_identifier);
4027
      if (update_method_vec_p)
4028
        add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4029
    }
4030
  else
4031
    {
4032
      gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4033
 
4034
      /* For each destructor, we need three variants: an in-charge
4035
         version, a not-in-charge version, and an in-charge deleting
4036
         version.  We clone the deleting version first because that
4037
         means it will go second on the TYPE_METHODS list -- and that
4038
         corresponds to the correct layout order in the virtual
4039
         function table.
4040
 
4041
         For a non-virtual destructor, we do not build a deleting
4042
         destructor.  */
4043
      if (DECL_VIRTUAL_P (fn))
4044
        {
4045
          clone = build_clone (fn, deleting_dtor_identifier);
4046
          if (update_method_vec_p)
4047
            add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4048
        }
4049
      clone = build_clone (fn, complete_dtor_identifier);
4050
      if (update_method_vec_p)
4051
        add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4052
      clone = build_clone (fn, base_dtor_identifier);
4053
      if (update_method_vec_p)
4054
        add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4055
    }
4056
 
4057
  /* Note that this is an abstract function that is never emitted.  */
4058
  DECL_ABSTRACT (fn) = 1;
4059
}
4060
 
4061
/* DECL is an in charge constructor, which is being defined. This will
4062
   have had an in class declaration, from whence clones were
4063
   declared. An out-of-class definition can specify additional default
4064
   arguments. As it is the clones that are involved in overload
4065
   resolution, we must propagate the information from the DECL to its
4066
   clones.  */
4067
 
4068
void
4069
adjust_clone_args (tree decl)
4070
{
4071
  tree clone;
4072
 
4073
  for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4074
       clone = TREE_CHAIN (clone))
4075
    {
4076
      tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4077
      tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4078
      tree decl_parms, clone_parms;
4079
 
4080
      clone_parms = orig_clone_parms;
4081
 
4082
      /* Skip the 'this' parameter.  */
4083
      orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4084
      orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4085
 
4086
      if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4087
        orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4088
      if (DECL_HAS_VTT_PARM_P (decl))
4089
        orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4090
 
4091
      clone_parms = orig_clone_parms;
4092
      if (DECL_HAS_VTT_PARM_P (clone))
4093
        clone_parms = TREE_CHAIN (clone_parms);
4094
 
4095
      for (decl_parms = orig_decl_parms; decl_parms;
4096
           decl_parms = TREE_CHAIN (decl_parms),
4097
             clone_parms = TREE_CHAIN (clone_parms))
4098
        {
4099
          gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4100
                                   TREE_TYPE (clone_parms)));
4101
 
4102
          if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4103
            {
4104
              /* A default parameter has been added. Adjust the
4105
                 clone's parameters.  */
4106
              tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4107
              tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4108
              tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4109
              tree type;
4110
 
4111
              clone_parms = orig_decl_parms;
4112
 
4113
              if (DECL_HAS_VTT_PARM_P (clone))
4114
                {
4115
                  clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4116
                                           TREE_VALUE (orig_clone_parms),
4117
                                           clone_parms);
4118
                  TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4119
                }
4120
              type = build_method_type_directly (basetype,
4121
                                                 TREE_TYPE (TREE_TYPE (clone)),
4122
                                                 clone_parms);
4123
              if (exceptions)
4124
                type = build_exception_variant (type, exceptions);
4125
              if (attrs)
4126
                type = cp_build_type_attribute_variant (type, attrs);
4127
              TREE_TYPE (clone) = type;
4128
 
4129
              clone_parms = NULL_TREE;
4130
              break;
4131
            }
4132
        }
4133
      gcc_assert (!clone_parms);
4134
    }
4135
}
4136
 
4137
/* For each of the constructors and destructors in T, create an
4138
   in-charge and not-in-charge variant.  */
4139
 
4140
static void
4141
clone_constructors_and_destructors (tree t)
4142
{
4143
  tree fns;
4144
 
4145
  /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4146
     out now.  */
4147
  if (!CLASSTYPE_METHOD_VEC (t))
4148
    return;
4149
 
4150
  for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4151
    clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4152
  for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4153
    clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4154
}
4155
 
4156
/* Returns true iff class T has a user-defined constructor other than
4157
   the default constructor.  */
4158
 
4159
bool
4160
type_has_user_nondefault_constructor (tree t)
4161
{
4162
  tree fns;
4163
 
4164
  if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4165
    return false;
4166
 
4167
  for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4168
    {
4169
      tree fn = OVL_CURRENT (fns);
4170
      if (!DECL_ARTIFICIAL (fn)
4171
          && (TREE_CODE (fn) == TEMPLATE_DECL
4172
              || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4173
                  != NULL_TREE)))
4174
        return true;
4175
    }
4176
 
4177
  return false;
4178
}
4179
 
4180
/* Returns true iff FN is a user-provided function, i.e. user-declared
4181
   and not defaulted at its first declaration; or explicit, private,
4182
   protected, or non-const.  */
4183
 
4184
bool
4185
user_provided_p (tree fn)
4186
{
4187
  if (TREE_CODE (fn) == TEMPLATE_DECL)
4188
    return true;
4189
  else
4190
    return (!DECL_ARTIFICIAL (fn)
4191
            && !DECL_DEFAULTED_IN_CLASS_P (fn));
4192
}
4193
 
4194
/* Returns true iff class T has a user-provided constructor.  */
4195
 
4196
bool
4197
type_has_user_provided_constructor (tree t)
4198
{
4199
  tree fns;
4200
 
4201
  if (!CLASS_TYPE_P (t))
4202
    return false;
4203
 
4204
  if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4205
    return false;
4206
 
4207
  /* This can happen in error cases; avoid crashing.  */
4208
  if (!CLASSTYPE_METHOD_VEC (t))
4209
    return false;
4210
 
4211
  for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4212
    if (user_provided_p (OVL_CURRENT (fns)))
4213
      return true;
4214
 
4215
  return false;
4216
}
4217
 
4218
/* Returns true iff class T has a user-provided default constructor.  */
4219
 
4220
bool
4221
type_has_user_provided_default_constructor (tree t)
4222
{
4223
  tree fns, args;
4224
 
4225
  if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4226
    return false;
4227
 
4228
  for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4229
    {
4230
      tree fn = OVL_CURRENT (fns);
4231
      if (TREE_CODE (fn) == FUNCTION_DECL
4232
          && user_provided_p (fn))
4233
        {
4234
          args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4235
          while (args && TREE_PURPOSE (args))
4236
            args = TREE_CHAIN (args);
4237
          if (!args || args == void_list_node)
4238
            return true;
4239
        }
4240
    }
4241
 
4242
  return false;
4243
}
4244
 
4245
/* Remove all zero-width bit-fields from T.  */
4246
 
4247
static void
4248
remove_zero_width_bit_fields (tree t)
4249
{
4250
  tree *fieldsp;
4251
 
4252
  fieldsp = &TYPE_FIELDS (t);
4253
  while (*fieldsp)
4254
    {
4255
      if (TREE_CODE (*fieldsp) == FIELD_DECL
4256
          && DECL_C_BIT_FIELD (*fieldsp)
4257
          /* We should not be confused by the fact that grokbitfield
4258
             temporarily sets the width of the bit field into
4259
             DECL_INITIAL (*fieldsp).
4260
             check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4261
             to that width.  */
4262
          && integer_zerop (DECL_SIZE (*fieldsp)))
4263
        *fieldsp = TREE_CHAIN (*fieldsp);
4264
      else
4265
        fieldsp = &TREE_CHAIN (*fieldsp);
4266
    }
4267
}
4268
 
4269
/* Returns TRUE iff we need a cookie when dynamically allocating an
4270
   array whose elements have the indicated class TYPE.  */
4271
 
4272
static bool
4273
type_requires_array_cookie (tree type)
4274
{
4275
  tree fns;
4276
  bool has_two_argument_delete_p = false;
4277
 
4278
  gcc_assert (CLASS_TYPE_P (type));
4279
 
4280
  /* If there's a non-trivial destructor, we need a cookie.  In order
4281
     to iterate through the array calling the destructor for each
4282
     element, we'll have to know how many elements there are.  */
4283
  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4284
    return true;
4285
 
4286
  /* If the usual deallocation function is a two-argument whose second
4287
     argument is of type `size_t', then we have to pass the size of
4288
     the array to the deallocation function, so we will need to store
4289
     a cookie.  */
4290
  fns = lookup_fnfields (TYPE_BINFO (type),
4291
                         ansi_opname (VEC_DELETE_EXPR),
4292
                         /*protect=*/0);
4293
  /* If there are no `operator []' members, or the lookup is
4294
     ambiguous, then we don't need a cookie.  */
4295
  if (!fns || fns == error_mark_node)
4296
    return false;
4297
  /* Loop through all of the functions.  */
4298
  for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4299
    {
4300
      tree fn;
4301
      tree second_parm;
4302
 
4303
      /* Select the current function.  */
4304
      fn = OVL_CURRENT (fns);
4305
      /* See if this function is a one-argument delete function.  If
4306
         it is, then it will be the usual deallocation function.  */
4307
      second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4308
      if (second_parm == void_list_node)
4309
        return false;
4310
      /* Do not consider this function if its second argument is an
4311
         ellipsis.  */
4312
      if (!second_parm)
4313
        continue;
4314
      /* Otherwise, if we have a two-argument function and the second
4315
         argument is `size_t', it will be the usual deallocation
4316
         function -- unless there is one-argument function, too.  */
4317
      if (TREE_CHAIN (second_parm) == void_list_node
4318
          && same_type_p (TREE_VALUE (second_parm), size_type_node))
4319
        has_two_argument_delete_p = true;
4320
    }
4321
 
4322
  return has_two_argument_delete_p;
4323
}
4324
 
4325
/* Check the validity of the bases and members declared in T.  Add any
4326
   implicitly-generated functions (like copy-constructors and
4327
   assignment operators).  Compute various flag bits (like
4328
   CLASSTYPE_NON_LAYOUT_POD_T) for T.  This routine works purely at the C++
4329
   level: i.e., independently of the ABI in use.  */
4330
 
4331
static void
4332
check_bases_and_members (tree t)
4333
{
4334
  /* Nonzero if the implicitly generated copy constructor should take
4335
     a non-const reference argument.  */
4336
  int cant_have_const_ctor;
4337
  /* Nonzero if the implicitly generated assignment operator
4338
     should take a non-const reference argument.  */
4339
  int no_const_asn_ref;
4340
  tree access_decls;
4341
  bool saved_complex_asn_ref;
4342
  bool saved_nontrivial_dtor;
4343
  tree fn;
4344
 
4345
  /* By default, we use const reference arguments and generate default
4346
     constructors.  */
4347
  cant_have_const_ctor = 0;
4348
  no_const_asn_ref = 0;
4349
 
4350
  /* Check all the base-classes.  */
4351
  check_bases (t, &cant_have_const_ctor,
4352
               &no_const_asn_ref);
4353
 
4354
  /* Check all the method declarations.  */
4355
  check_methods (t);
4356
 
4357
  /* Save the initial values of these flags which only indicate whether
4358
     or not the class has user-provided functions.  As we analyze the
4359
     bases and members we can set these flags for other reasons.  */
4360
  saved_complex_asn_ref = TYPE_HAS_COMPLEX_ASSIGN_REF (t);
4361
  saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4362
 
4363
  /* Check all the data member declarations.  We cannot call
4364
     check_field_decls until we have called check_bases check_methods,
4365
     as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4366
     being set appropriately.  */
4367
  check_field_decls (t, &access_decls,
4368
                     &cant_have_const_ctor,
4369
                     &no_const_asn_ref);
4370
 
4371
  /* A nearly-empty class has to be vptr-containing; a nearly empty
4372
     class contains just a vptr.  */
4373
  if (!TYPE_CONTAINS_VPTR_P (t))
4374
    CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4375
 
4376
  /* Do some bookkeeping that will guide the generation of implicitly
4377
     declared member functions.  */
4378
  TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4379
  /* We need to call a constructor for this class if it has a
4380
     user-provided constructor, or if the default constructor is going
4381
     to initialize the vptr.  (This is not an if-and-only-if;
4382
     TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4383
     themselves need constructing.)  */
4384
  TYPE_NEEDS_CONSTRUCTING (t)
4385
    |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4386
  /* [dcl.init.aggr]
4387
 
4388
     An aggregate is an array or a class with no user-provided
4389
     constructors ... and no virtual functions.
4390
 
4391
     Again, other conditions for being an aggregate are checked
4392
     elsewhere.  */
4393
  CLASSTYPE_NON_AGGREGATE (t)
4394
    |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4395
  /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4396
     retain the old definition internally for ABI reasons.  */
4397
  CLASSTYPE_NON_LAYOUT_POD_P (t)
4398
    |= (CLASSTYPE_NON_AGGREGATE (t)
4399
        || saved_nontrivial_dtor || saved_complex_asn_ref);
4400
  CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4401
  TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4402
  TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4403
 
4404
  /* If the class has no user-declared constructor, but does have
4405
     non-static const or reference data members that can never be
4406
     initialized, issue a warning.  */
4407
  if (warn_uninitialized
4408
      /* Classes with user-declared constructors are presumed to
4409
         initialize these members.  */
4410
      && !TYPE_HAS_USER_CONSTRUCTOR (t)
4411
      /* Aggregates can be initialized with brace-enclosed
4412
         initializers.  */
4413
      && CLASSTYPE_NON_AGGREGATE (t))
4414
    {
4415
      tree field;
4416
 
4417
      for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4418
        {
4419
          tree type;
4420
 
4421
          if (TREE_CODE (field) != FIELD_DECL)
4422
            continue;
4423
 
4424
          type = TREE_TYPE (field);
4425
          if (TREE_CODE (type) == REFERENCE_TYPE)
4426
            warning (OPT_Wuninitialized, "non-static reference %q+#D "
4427
                     "in class without a constructor", field);
4428
          else if (CP_TYPE_CONST_P (type)
4429
                   && (!CLASS_TYPE_P (type)
4430
                       || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4431
            warning (OPT_Wuninitialized, "non-static const member %q+#D "
4432
                     "in class without a constructor", field);
4433
        }
4434
    }
4435
 
4436
  /* Synthesize any needed methods.  */
4437
  add_implicitly_declared_members (t,
4438
                                   cant_have_const_ctor,
4439
                                   no_const_asn_ref);
4440
 
4441
  /* Check defaulted declarations here so we have cant_have_const_ctor
4442
     and don't need to worry about clones.  */
4443
  for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4444
    if (DECL_DEFAULTED_IN_CLASS_P (fn))
4445
      {
4446
        int copy = copy_fn_p (fn);
4447
        if (copy > 0)
4448
          {
4449
            bool imp_const_p
4450
              = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4451
                 : !no_const_asn_ref);
4452
            bool fn_const_p = (copy == 2);
4453
 
4454
            if (fn_const_p && !imp_const_p)
4455
              /* If the function is defaulted outside the class, we just
4456
                 give the synthesis error.  */
4457
              error ("%q+D declared to take const reference, but implicit "
4458
                     "declaration would take non-const", fn);
4459
            else if (imp_const_p && !fn_const_p)
4460
              error ("%q+D declared to take non-const reference cannot be "
4461
                     "defaulted in the class body", fn);
4462
          }
4463
        defaulted_late_check (fn);
4464
      }
4465
 
4466
  if (LAMBDA_TYPE_P (t))
4467
    {
4468
      /* "The closure type associated with a lambda-expression has a deleted
4469
         default constructor and a deleted copy assignment operator."  */
4470
      TYPE_NEEDS_CONSTRUCTING (t) = 1;
4471
      TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 0;
4472
      CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 0;
4473
      TYPE_HAS_ASSIGN_REF (t) = 0;
4474
      CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 0;
4475
 
4476
      /* "This class type is not an aggregate."  */
4477
      CLASSTYPE_NON_AGGREGATE (t) = 1;
4478
    }
4479
 
4480
  /* Create the in-charge and not-in-charge variants of constructors
4481
     and destructors.  */
4482
  clone_constructors_and_destructors (t);
4483
 
4484
  /* Process the using-declarations.  */
4485
  for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4486
    handle_using_decl (TREE_VALUE (access_decls), t);
4487
 
4488
  /* Build and sort the CLASSTYPE_METHOD_VEC.  */
4489
  finish_struct_methods (t);
4490
 
4491
  /* Figure out whether or not we will need a cookie when dynamically
4492
     allocating an array of this type.  */
4493
  TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4494
    = type_requires_array_cookie (t);
4495
}
4496
 
4497
/* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4498
   accordingly.  If a new vfield was created (because T doesn't have a
4499
   primary base class), then the newly created field is returned.  It
4500
   is not added to the TYPE_FIELDS list; it is the caller's
4501
   responsibility to do that.  Accumulate declared virtual functions
4502
   on VIRTUALS_P.  */
4503
 
4504
static tree
4505
create_vtable_ptr (tree t, tree* virtuals_p)
4506
{
4507
  tree fn;
4508
 
4509
  /* Collect the virtual functions declared in T.  */
4510
  for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4511
    if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4512
        && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4513
      {
4514
        tree new_virtual = make_node (TREE_LIST);
4515
 
4516
        BV_FN (new_virtual) = fn;
4517
        BV_DELTA (new_virtual) = integer_zero_node;
4518
        BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4519
 
4520
        TREE_CHAIN (new_virtual) = *virtuals_p;
4521
        *virtuals_p = new_virtual;
4522
      }
4523
 
4524
  /* If we couldn't find an appropriate base class, create a new field
4525
     here.  Even if there weren't any new virtual functions, we might need a
4526
     new virtual function table if we're supposed to include vptrs in
4527
     all classes that need them.  */
4528
  if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4529
    {
4530
      /* We build this decl with vtbl_ptr_type_node, which is a
4531
         `vtable_entry_type*'.  It might seem more precise to use
4532
         `vtable_entry_type (*)[N]' where N is the number of virtual
4533
         functions.  However, that would require the vtable pointer in
4534
         base classes to have a different type than the vtable pointer
4535
         in derived classes.  We could make that happen, but that
4536
         still wouldn't solve all the problems.  In particular, the
4537
         type-based alias analysis code would decide that assignments
4538
         to the base class vtable pointer can't alias assignments to
4539
         the derived class vtable pointer, since they have different
4540
         types.  Thus, in a derived class destructor, where the base
4541
         class constructor was inlined, we could generate bad code for
4542
         setting up the vtable pointer.
4543
 
4544
         Therefore, we use one type for all vtable pointers.  We still
4545
         use a type-correct type; it's just doesn't indicate the array
4546
         bounds.  That's better than using `void*' or some such; it's
4547
         cleaner, and it let's the alias analysis code know that these
4548
         stores cannot alias stores to void*!  */
4549
      tree field;
4550
 
4551
      field = build_decl (input_location,
4552
                          FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4553
      DECL_VIRTUAL_P (field) = 1;
4554
      DECL_ARTIFICIAL (field) = 1;
4555
      DECL_FIELD_CONTEXT (field) = t;
4556
      DECL_FCONTEXT (field) = t;
4557
      if (TYPE_PACKED (t))
4558
        DECL_PACKED (field) = 1;
4559
 
4560
      TYPE_VFIELD (t) = field;
4561
 
4562
      /* This class is non-empty.  */
4563
      CLASSTYPE_EMPTY_P (t) = 0;
4564
 
4565
      return field;
4566
    }
4567
 
4568
  return NULL_TREE;
4569
}
4570
 
4571
/* Add OFFSET to all base types of BINFO which is a base in the
4572
   hierarchy dominated by T.
4573
 
4574
   OFFSET, which is a type offset, is number of bytes.  */
4575
 
4576
static void
4577
propagate_binfo_offsets (tree binfo, tree offset)
4578
{
4579
  int i;
4580
  tree primary_binfo;
4581
  tree base_binfo;
4582
 
4583
  /* Update BINFO's offset.  */
4584
  BINFO_OFFSET (binfo)
4585
    = convert (sizetype,
4586
               size_binop (PLUS_EXPR,
4587
                           convert (ssizetype, BINFO_OFFSET (binfo)),
4588
                           offset));
4589
 
4590
  /* Find the primary base class.  */
4591
  primary_binfo = get_primary_binfo (binfo);
4592
 
4593
  if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4594
    propagate_binfo_offsets (primary_binfo, offset);
4595
 
4596
  /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4597
     downwards.  */
4598
  for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4599
    {
4600
      /* Don't do the primary base twice.  */
4601
      if (base_binfo == primary_binfo)
4602
        continue;
4603
 
4604
      if (BINFO_VIRTUAL_P (base_binfo))
4605
        continue;
4606
 
4607
      propagate_binfo_offsets (base_binfo, offset);
4608
    }
4609
}
4610
 
4611
/* Set BINFO_OFFSET for all of the virtual bases for RLI->T.  Update
4612
   TYPE_ALIGN and TYPE_SIZE for T.  OFFSETS gives the location of
4613
   empty subobjects of T.  */
4614
 
4615
static void
4616
layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4617
{
4618
  tree vbase;
4619
  tree t = rli->t;
4620
  bool first_vbase = true;
4621
  tree *next_field;
4622
 
4623
  if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4624
    return;
4625
 
4626
  if (!abi_version_at_least(2))
4627
    {
4628
      /* In G++ 3.2, we incorrectly rounded the size before laying out
4629
         the virtual bases.  */
4630
      finish_record_layout (rli, /*free_p=*/false);
4631
#ifdef STRUCTURE_SIZE_BOUNDARY
4632
      /* Packed structures don't need to have minimum size.  */
4633
      if (! TYPE_PACKED (t))
4634
        TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4635
#endif
4636
      rli->offset = TYPE_SIZE_UNIT (t);
4637
      rli->bitpos = bitsize_zero_node;
4638
      rli->record_align = TYPE_ALIGN (t);
4639
    }
4640
 
4641
  /* Find the last field.  The artificial fields created for virtual
4642
     bases will go after the last extant field to date.  */
4643
  next_field = &TYPE_FIELDS (t);
4644
  while (*next_field)
4645
    next_field = &TREE_CHAIN (*next_field);
4646
 
4647
  /* Go through the virtual bases, allocating space for each virtual
4648
     base that is not already a primary base class.  These are
4649
     allocated in inheritance graph order.  */
4650
  for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4651
    {
4652
      if (!BINFO_VIRTUAL_P (vbase))
4653
        continue;
4654
 
4655
      if (!BINFO_PRIMARY_P (vbase))
4656
        {
4657
          tree basetype = TREE_TYPE (vbase);
4658
 
4659
          /* This virtual base is not a primary base of any class in the
4660
             hierarchy, so we have to add space for it.  */
4661
          next_field = build_base_field (rli, vbase,
4662
                                         offsets, next_field);
4663
 
4664
          /* If the first virtual base might have been placed at a
4665
             lower address, had we started from CLASSTYPE_SIZE, rather
4666
             than TYPE_SIZE, issue a warning.  There can be both false
4667
             positives and false negatives from this warning in rare
4668
             cases; to deal with all the possibilities would probably
4669
             require performing both layout algorithms and comparing
4670
             the results which is not particularly tractable.  */
4671
          if (warn_abi
4672
              && first_vbase
4673
              && (tree_int_cst_lt
4674
                  (size_binop (CEIL_DIV_EXPR,
4675
                               round_up_loc (input_location,
4676
                                         CLASSTYPE_SIZE (t),
4677
                                         CLASSTYPE_ALIGN (basetype)),
4678
                               bitsize_unit_node),
4679
                   BINFO_OFFSET (vbase))))
4680
            warning (OPT_Wabi,
4681
                     "offset of virtual base %qT is not ABI-compliant and "
4682
                     "may change in a future version of GCC",
4683
                     basetype);
4684
 
4685
          first_vbase = false;
4686
        }
4687
    }
4688
}
4689
 
4690
/* Returns the offset of the byte just past the end of the base class
4691
   BINFO.  */
4692
 
4693
static tree
4694
end_of_base (tree binfo)
4695
{
4696
  tree size;
4697
 
4698
  if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4699
    size = TYPE_SIZE_UNIT (char_type_node);
4700
  else if (is_empty_class (BINFO_TYPE (binfo)))
4701
    /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4702
       allocate some space for it. It cannot have virtual bases, so
4703
       TYPE_SIZE_UNIT is fine.  */
4704
    size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4705
  else
4706
    size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4707
 
4708
  return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4709
}
4710
 
4711
/* Returns the offset of the byte just past the end of the base class
4712
   with the highest offset in T.  If INCLUDE_VIRTUALS_P is zero, then
4713
   only non-virtual bases are included.  */
4714
 
4715
static tree
4716
end_of_class (tree t, int include_virtuals_p)
4717
{
4718
  tree result = size_zero_node;
4719
  VEC(tree,gc) *vbases;
4720
  tree binfo;
4721
  tree base_binfo;
4722
  tree offset;
4723
  int i;
4724
 
4725
  for (binfo = TYPE_BINFO (t), i = 0;
4726
       BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4727
    {
4728
      if (!include_virtuals_p
4729
          && BINFO_VIRTUAL_P (base_binfo)
4730
          && (!BINFO_PRIMARY_P (base_binfo)
4731
              || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4732
        continue;
4733
 
4734
      offset = end_of_base (base_binfo);
4735
      if (INT_CST_LT_UNSIGNED (result, offset))
4736
        result = offset;
4737
    }
4738
 
4739
  /* G++ 3.2 did not check indirect virtual bases.  */
4740
  if (abi_version_at_least (2) && include_virtuals_p)
4741
    for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4742
         VEC_iterate (tree, vbases, i, base_binfo); i++)
4743
      {
4744
        offset = end_of_base (base_binfo);
4745
        if (INT_CST_LT_UNSIGNED (result, offset))
4746
          result = offset;
4747
      }
4748
 
4749
  return result;
4750
}
4751
 
4752
/* Warn about bases of T that are inaccessible because they are
4753
   ambiguous.  For example:
4754
 
4755
     struct S {};
4756
     struct T : public S {};
4757
     struct U : public S, public T {};
4758
 
4759
   Here, `(S*) new U' is not allowed because there are two `S'
4760
   subobjects of U.  */
4761
 
4762
static void
4763
warn_about_ambiguous_bases (tree t)
4764
{
4765
  int i;
4766
  VEC(tree,gc) *vbases;
4767
  tree basetype;
4768
  tree binfo;
4769
  tree base_binfo;
4770
 
4771
  /* If there are no repeated bases, nothing can be ambiguous.  */
4772
  if (!CLASSTYPE_REPEATED_BASE_P (t))
4773
    return;
4774
 
4775
  /* Check direct bases.  */
4776
  for (binfo = TYPE_BINFO (t), i = 0;
4777
       BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4778
    {
4779
      basetype = BINFO_TYPE (base_binfo);
4780
 
4781
      if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4782
        warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4783
                 basetype, t);
4784
    }
4785
 
4786
  /* Check for ambiguous virtual bases.  */
4787
  if (extra_warnings)
4788
    for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4789
         VEC_iterate (tree, vbases, i, binfo); i++)
4790
      {
4791
        basetype = BINFO_TYPE (binfo);
4792
 
4793
        if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4794
          warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4795
                   basetype, t);
4796
      }
4797
}
4798
 
4799
/* Compare two INTEGER_CSTs K1 and K2.  */
4800
 
4801
static int
4802
splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4803
{
4804
  return tree_int_cst_compare ((tree) k1, (tree) k2);
4805
}
4806
 
4807
/* Increase the size indicated in RLI to account for empty classes
4808
   that are "off the end" of the class.  */
4809
 
4810
static void
4811
include_empty_classes (record_layout_info rli)
4812
{
4813
  tree eoc;
4814
  tree rli_size;
4815
 
4816
  /* It might be the case that we grew the class to allocate a
4817
     zero-sized base class.  That won't be reflected in RLI, yet,
4818
     because we are willing to overlay multiple bases at the same
4819
     offset.  However, now we need to make sure that RLI is big enough
4820
     to reflect the entire class.  */
4821
  eoc = end_of_class (rli->t,
4822
                      CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4823
  rli_size = rli_size_unit_so_far (rli);
4824
  if (TREE_CODE (rli_size) == INTEGER_CST
4825
      && INT_CST_LT_UNSIGNED (rli_size, eoc))
4826
    {
4827
      if (!abi_version_at_least (2))
4828
        /* In version 1 of the ABI, the size of a class that ends with
4829
           a bitfield was not rounded up to a whole multiple of a
4830
           byte.  Because rli_size_unit_so_far returns only the number
4831
           of fully allocated bytes, any extra bits were not included
4832
           in the size.  */
4833
        rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4834
      else
4835
        /* The size should have been rounded to a whole byte.  */
4836
        gcc_assert (tree_int_cst_equal
4837
                    (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4838
      rli->bitpos
4839
        = size_binop (PLUS_EXPR,
4840
                      rli->bitpos,
4841
                      size_binop (MULT_EXPR,
4842
                                  convert (bitsizetype,
4843
                                           size_binop (MINUS_EXPR,
4844
                                                       eoc, rli_size)),
4845
                                  bitsize_int (BITS_PER_UNIT)));
4846
      normalize_rli (rli);
4847
    }
4848
}
4849
 
4850
/* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T.  Calculate
4851
   BINFO_OFFSETs for all of the base-classes.  Position the vtable
4852
   pointer.  Accumulate declared virtual functions on VIRTUALS_P.  */
4853
 
4854
static void
4855
layout_class_type (tree t, tree *virtuals_p)
4856
{
4857
  tree non_static_data_members;
4858
  tree field;
4859
  tree vptr;
4860
  record_layout_info rli;
4861
  /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4862
     types that appear at that offset.  */
4863
  splay_tree empty_base_offsets;
4864
  /* True if the last field layed out was a bit-field.  */
4865
  bool last_field_was_bitfield = false;
4866
  /* The location at which the next field should be inserted.  */
4867
  tree *next_field;
4868
  /* T, as a base class.  */
4869
  tree base_t;
4870
 
4871
  /* Keep track of the first non-static data member.  */
4872
  non_static_data_members = TYPE_FIELDS (t);
4873
 
4874
  /* Start laying out the record.  */
4875
  rli = start_record_layout (t);
4876
 
4877
  /* Mark all the primary bases in the hierarchy.  */
4878
  determine_primary_bases (t);
4879
 
4880
  /* Create a pointer to our virtual function table.  */
4881
  vptr = create_vtable_ptr (t, virtuals_p);
4882
 
4883
  /* The vptr is always the first thing in the class.  */
4884
  if (vptr)
4885
    {
4886
      TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4887
      TYPE_FIELDS (t) = vptr;
4888
      next_field = &TREE_CHAIN (vptr);
4889
      place_field (rli, vptr);
4890
    }
4891
  else
4892
    next_field = &TYPE_FIELDS (t);
4893
 
4894
  /* Build FIELD_DECLs for all of the non-virtual base-types.  */
4895
  empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4896
                                       NULL, NULL);
4897
  build_base_fields (rli, empty_base_offsets, next_field);
4898
 
4899
  /* Layout the non-static data members.  */
4900
  for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4901
    {
4902
      tree type;
4903
      tree padding;
4904
 
4905
      /* We still pass things that aren't non-static data members to
4906
         the back end, in case it wants to do something with them.  */
4907
      if (TREE_CODE (field) != FIELD_DECL)
4908
        {
4909
          place_field (rli, field);
4910
          /* If the static data member has incomplete type, keep track
4911
             of it so that it can be completed later.  (The handling
4912
             of pending statics in finish_record_layout is
4913
             insufficient; consider:
4914
 
4915
               struct S1;
4916
               struct S2 { static S1 s1; };
4917
 
4918
             At this point, finish_record_layout will be called, but
4919
             S1 is still incomplete.)  */
4920
          if (TREE_CODE (field) == VAR_DECL)
4921
            {
4922
              maybe_register_incomplete_var (field);
4923
              /* The visibility of static data members is determined
4924
                 at their point of declaration, not their point of
4925
                 definition.  */
4926
              determine_visibility (field);
4927
            }
4928
          continue;
4929
        }
4930
 
4931
      type = TREE_TYPE (field);
4932
      if (type == error_mark_node)
4933
        continue;
4934
 
4935
      padding = NULL_TREE;
4936
 
4937
      /* If this field is a bit-field whose width is greater than its
4938
         type, then there are some special rules for allocating
4939
         it.  */
4940
      if (DECL_C_BIT_FIELD (field)
4941
          && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4942
        {
4943
          unsigned int itk;
4944
          tree integer_type;
4945
          bool was_unnamed_p = false;
4946
          /* We must allocate the bits as if suitably aligned for the
4947
             longest integer type that fits in this many bits.  type
4948
             of the field.  Then, we are supposed to use the left over
4949
             bits as additional padding.  */
4950
          for (itk = itk_char; itk != itk_none; ++itk)
4951
            if (INT_CST_LT (DECL_SIZE (field),
4952
                            TYPE_SIZE (integer_types[itk])))
4953
              break;
4954
 
4955
          /* ITK now indicates a type that is too large for the
4956
             field.  We have to back up by one to find the largest
4957
             type that fits.  */
4958
          integer_type = integer_types[itk - 1];
4959
 
4960
          /* Figure out how much additional padding is required.  GCC
4961
             3.2 always created a padding field, even if it had zero
4962
             width.  */
4963
          if (!abi_version_at_least (2)
4964
              || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4965
            {
4966
              if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4967
                /* In a union, the padding field must have the full width
4968
                   of the bit-field; all fields start at offset zero.  */
4969
                padding = DECL_SIZE (field);
4970
              else
4971
                {
4972
                  if (TREE_CODE (t) == UNION_TYPE)
4973
                    warning (OPT_Wabi, "size assigned to %qT may not be "
4974
                             "ABI-compliant and may change in a future "
4975
                             "version of GCC",
4976
                             t);
4977
                  padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4978
                                        TYPE_SIZE (integer_type));
4979
                }
4980
            }
4981
#ifdef PCC_BITFIELD_TYPE_MATTERS
4982
          /* An unnamed bitfield does not normally affect the
4983
             alignment of the containing class on a target where
4984
             PCC_BITFIELD_TYPE_MATTERS.  But, the C++ ABI does not
4985
             make any exceptions for unnamed bitfields when the
4986
             bitfields are longer than their types.  Therefore, we
4987
             temporarily give the field a name.  */
4988
          if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4989
            {
4990
              was_unnamed_p = true;
4991
              DECL_NAME (field) = make_anon_name ();
4992
            }
4993
#endif
4994
          DECL_SIZE (field) = TYPE_SIZE (integer_type);
4995
          DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4996
          DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4997
          layout_nonempty_base_or_field (rli, field, NULL_TREE,
4998
                                         empty_base_offsets);
4999
          if (was_unnamed_p)
5000
            DECL_NAME (field) = NULL_TREE;
5001
          /* Now that layout has been performed, set the size of the
5002
             field to the size of its declared type; the rest of the
5003
             field is effectively invisible.  */
5004
          DECL_SIZE (field) = TYPE_SIZE (type);
5005
          /* We must also reset the DECL_MODE of the field.  */
5006
          if (abi_version_at_least (2))
5007
            DECL_MODE (field) = TYPE_MODE (type);
5008
          else if (warn_abi
5009
                   && DECL_MODE (field) != TYPE_MODE (type))
5010
            /* Versions of G++ before G++ 3.4 did not reset the
5011
               DECL_MODE.  */
5012
            warning (OPT_Wabi,
5013
                     "the offset of %qD may not be ABI-compliant and may "
5014
                     "change in a future version of GCC", field);
5015
        }
5016
      else
5017
        layout_nonempty_base_or_field (rli, field, NULL_TREE,
5018
                                       empty_base_offsets);
5019
 
5020
      /* Remember the location of any empty classes in FIELD.  */
5021
      if (abi_version_at_least (2))
5022
        record_subobject_offsets (TREE_TYPE (field),
5023
                                  byte_position(field),
5024
                                  empty_base_offsets,
5025
                                  /*is_data_member=*/true);
5026
 
5027
      /* If a bit-field does not immediately follow another bit-field,
5028
         and yet it starts in the middle of a byte, we have failed to
5029
         comply with the ABI.  */
5030
      if (warn_abi
5031
          && DECL_C_BIT_FIELD (field)
5032
          /* The TREE_NO_WARNING flag gets set by Objective-C when
5033
             laying out an Objective-C class.  The ObjC ABI differs
5034
             from the C++ ABI, and so we do not want a warning
5035
             here.  */
5036
          && !TREE_NO_WARNING (field)
5037
          && !last_field_was_bitfield
5038
          && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5039
                                         DECL_FIELD_BIT_OFFSET (field),
5040
                                         bitsize_unit_node)))
5041
        warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5042
                 "change in a future version of GCC", field);
5043
 
5044
      /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5045
         offset of the field.  */
5046
      if (warn_abi
5047
          && !abi_version_at_least (2)
5048
          && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5049
                                  byte_position (field))
5050
          && contains_empty_class_p (TREE_TYPE (field)))
5051
        warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5052
                 "classes to be placed at different locations in a "
5053
                 "future version of GCC", field);
5054
 
5055
      /* The middle end uses the type of expressions to determine the
5056
         possible range of expression values.  In order to optimize
5057
         "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5058
         must be made aware of the width of "i", via its type.
5059
 
5060
         Because C++ does not have integer types of arbitrary width,
5061
         we must (for the purposes of the front end) convert from the
5062
         type assigned here to the declared type of the bitfield
5063
         whenever a bitfield expression is used as an rvalue.
5064
         Similarly, when assigning a value to a bitfield, the value
5065
         must be converted to the type given the bitfield here.  */
5066
      if (DECL_C_BIT_FIELD (field))
5067
        {
5068
          unsigned HOST_WIDE_INT width;
5069
          tree ftype = TREE_TYPE (field);
5070
          width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5071
          if (width != TYPE_PRECISION (ftype))
5072
            {
5073
              TREE_TYPE (field)
5074
                = c_build_bitfield_integer_type (width,
5075
                                                 TYPE_UNSIGNED (ftype));
5076
              TREE_TYPE (field)
5077
                = cp_build_qualified_type (TREE_TYPE (field),
5078
                                           TYPE_QUALS (ftype));
5079
            }
5080
        }
5081
 
5082
      /* If we needed additional padding after this field, add it
5083
         now.  */
5084
      if (padding)
5085
        {
5086
          tree padding_field;
5087
 
5088
          padding_field = build_decl (input_location,
5089
                                      FIELD_DECL,
5090
                                      NULL_TREE,
5091
                                      char_type_node);
5092
          DECL_BIT_FIELD (padding_field) = 1;
5093
          DECL_SIZE (padding_field) = padding;
5094
          DECL_CONTEXT (padding_field) = t;
5095
          DECL_ARTIFICIAL (padding_field) = 1;
5096
          DECL_IGNORED_P (padding_field) = 1;
5097
          layout_nonempty_base_or_field (rli, padding_field,
5098
                                         NULL_TREE,
5099
                                         empty_base_offsets);
5100
        }
5101
 
5102
      last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5103
    }
5104
 
5105
  if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5106
    {
5107
      /* Make sure that we are on a byte boundary so that the size of
5108
         the class without virtual bases will always be a round number
5109
         of bytes.  */
5110
      rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5111
      normalize_rli (rli);
5112
    }
5113
 
5114
  /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5115
     padding.  */
5116
  if (!abi_version_at_least (2))
5117
    include_empty_classes(rli);
5118
 
5119
  /* Delete all zero-width bit-fields from the list of fields.  Now
5120
     that the type is laid out they are no longer important.  */
5121
  remove_zero_width_bit_fields (t);
5122
 
5123
  /* Create the version of T used for virtual bases.  We do not use
5124
     make_class_type for this version; this is an artificial type.  For
5125
     a POD type, we just reuse T.  */
5126
  if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5127
    {
5128
      base_t = make_node (TREE_CODE (t));
5129
 
5130
      /* Set the size and alignment for the new type.  In G++ 3.2, all
5131
         empty classes were considered to have size zero when used as
5132
         base classes.  */
5133
      if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5134
        {
5135
          TYPE_SIZE (base_t) = bitsize_zero_node;
5136
          TYPE_SIZE_UNIT (base_t) = size_zero_node;
5137
          if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5138
            warning (OPT_Wabi,
5139
                     "layout of classes derived from empty class %qT "
5140
                     "may change in a future version of GCC",
5141
                     t);
5142
        }
5143
      else
5144
        {
5145
          tree eoc;
5146
 
5147
          /* If the ABI version is not at least two, and the last
5148
             field was a bit-field, RLI may not be on a byte
5149
             boundary.  In particular, rli_size_unit_so_far might
5150
             indicate the last complete byte, while rli_size_so_far
5151
             indicates the total number of bits used.  Therefore,
5152
             rli_size_so_far, rather than rli_size_unit_so_far, is
5153
             used to compute TYPE_SIZE_UNIT.  */
5154
          eoc = end_of_class (t, /*include_virtuals_p=*/0);
5155
          TYPE_SIZE_UNIT (base_t)
5156
            = size_binop (MAX_EXPR,
5157
                          convert (sizetype,
5158
                                   size_binop (CEIL_DIV_EXPR,
5159
                                               rli_size_so_far (rli),
5160
                                               bitsize_int (BITS_PER_UNIT))),
5161
                          eoc);
5162
          TYPE_SIZE (base_t)
5163
            = size_binop (MAX_EXPR,
5164
                          rli_size_so_far (rli),
5165
                          size_binop (MULT_EXPR,
5166
                                      convert (bitsizetype, eoc),
5167
                                      bitsize_int (BITS_PER_UNIT)));
5168
        }
5169
      TYPE_ALIGN (base_t) = rli->record_align;
5170
      TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5171
 
5172
      /* Copy the fields from T.  */
5173
      next_field = &TYPE_FIELDS (base_t);
5174
      for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5175
        if (TREE_CODE (field) == FIELD_DECL)
5176
          {
5177
            *next_field = build_decl (input_location,
5178
                                      FIELD_DECL,
5179
                                      DECL_NAME (field),
5180
                                      TREE_TYPE (field));
5181
            DECL_CONTEXT (*next_field) = base_t;
5182
            DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5183
            DECL_FIELD_BIT_OFFSET (*next_field)
5184
              = DECL_FIELD_BIT_OFFSET (field);
5185
            DECL_SIZE (*next_field) = DECL_SIZE (field);
5186
            DECL_MODE (*next_field) = DECL_MODE (field);
5187
            next_field = &TREE_CHAIN (*next_field);
5188
          }
5189
 
5190
      /* Record the base version of the type.  */
5191
      CLASSTYPE_AS_BASE (t) = base_t;
5192
      TYPE_CONTEXT (base_t) = t;
5193
    }
5194
  else
5195
    CLASSTYPE_AS_BASE (t) = t;
5196
 
5197
  /* Every empty class contains an empty class.  */
5198
  if (CLASSTYPE_EMPTY_P (t))
5199
    CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5200
 
5201
  /* Set the TYPE_DECL for this type to contain the right
5202
     value for DECL_OFFSET, so that we can use it as part
5203
     of a COMPONENT_REF for multiple inheritance.  */
5204
  layout_decl (TYPE_MAIN_DECL (t), 0);
5205
 
5206
  /* Now fix up any virtual base class types that we left lying
5207
     around.  We must get these done before we try to lay out the
5208
     virtual function table.  As a side-effect, this will remove the
5209
     base subobject fields.  */
5210
  layout_virtual_bases (rli, empty_base_offsets);
5211
 
5212
  /* Make sure that empty classes are reflected in RLI at this
5213
     point.  */
5214
  include_empty_classes(rli);
5215
 
5216
  /* Make sure not to create any structures with zero size.  */
5217
  if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5218
    place_field (rli,
5219
                 build_decl (input_location,
5220
                             FIELD_DECL, NULL_TREE, char_type_node));
5221
 
5222
  /* If this is a non-POD, declaring it packed makes a difference to how it
5223
     can be used as a field; don't let finalize_record_size undo it.  */
5224
  if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5225
    rli->packed_maybe_necessary = true;
5226
 
5227
  /* Let the back end lay out the type.  */
5228
  finish_record_layout (rli, /*free_p=*/true);
5229
 
5230
  /* Warn about bases that can't be talked about due to ambiguity.  */
5231
  warn_about_ambiguous_bases (t);
5232
 
5233
  /* Now that we're done with layout, give the base fields the real types.  */
5234
  for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5235
    if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5236
      TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5237
 
5238
  /* Clean up.  */
5239
  splay_tree_delete (empty_base_offsets);
5240
 
5241
  if (CLASSTYPE_EMPTY_P (t)
5242
      && tree_int_cst_lt (sizeof_biggest_empty_class,
5243
                          TYPE_SIZE_UNIT (t)))
5244
    sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5245
}
5246
 
5247
/* Determine the "key method" for the class type indicated by TYPE,
5248
   and set CLASSTYPE_KEY_METHOD accordingly.  */
5249
 
5250
void
5251
determine_key_method (tree type)
5252
{
5253
  tree method;
5254
 
5255
  if (TYPE_FOR_JAVA (type)
5256
      || processing_template_decl
5257
      || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5258
      || CLASSTYPE_INTERFACE_KNOWN (type))
5259
    return;
5260
 
5261
  /* The key method is the first non-pure virtual function that is not
5262
     inline at the point of class definition.  On some targets the
5263
     key function may not be inline; those targets should not call
5264
     this function until the end of the translation unit.  */
5265
  for (method = TYPE_METHODS (type); method != NULL_TREE;
5266
       method = TREE_CHAIN (method))
5267
    if (DECL_VINDEX (method) != NULL_TREE
5268
        && ! DECL_DECLARED_INLINE_P (method)
5269
        && ! DECL_PURE_VIRTUAL_P (method))
5270
      {
5271
        CLASSTYPE_KEY_METHOD (type) = method;
5272
        break;
5273
      }
5274
 
5275
  return;
5276
}
5277
 
5278
/* Perform processing required when the definition of T (a class type)
5279
   is complete.  */
5280
 
5281
void
5282
finish_struct_1 (tree t)
5283
{
5284
  tree x;
5285
  /* A TREE_LIST.  The TREE_VALUE of each node is a FUNCTION_DECL.  */
5286
  tree virtuals = NULL_TREE;
5287
  int n_fields = 0;
5288
 
5289
  if (COMPLETE_TYPE_P (t))
5290
    {
5291
      gcc_assert (MAYBE_CLASS_TYPE_P (t));
5292
      error ("redefinition of %q#T", t);
5293
      popclass ();
5294
      return;
5295
    }
5296
 
5297
  /* If this type was previously laid out as a forward reference,
5298
     make sure we lay it out again.  */
5299
  TYPE_SIZE (t) = NULL_TREE;
5300
  CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5301
 
5302
  /* Make assumptions about the class; we'll reset the flags if
5303
     necessary.  */
5304
  CLASSTYPE_EMPTY_P (t) = 1;
5305
  CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5306
  CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5307
 
5308
  /* Do end-of-class semantic processing: checking the validity of the
5309
     bases and members and add implicitly generated methods.  */
5310
  check_bases_and_members (t);
5311
 
5312
  /* Find the key method.  */
5313
  if (TYPE_CONTAINS_VPTR_P (t))
5314
    {
5315
      /* The Itanium C++ ABI permits the key method to be chosen when
5316
         the class is defined -- even though the key method so
5317
         selected may later turn out to be an inline function.  On
5318
         some systems (such as ARM Symbian OS) the key method cannot
5319
         be determined until the end of the translation unit.  On such
5320
         systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5321
         will cause the class to be added to KEYED_CLASSES.  Then, in
5322
         finish_file we will determine the key method.  */
5323
      if (targetm.cxx.key_method_may_be_inline ())
5324
        determine_key_method (t);
5325
 
5326
      /* If a polymorphic class has no key method, we may emit the vtable
5327
         in every translation unit where the class definition appears.  */
5328
      if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5329
        keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5330
    }
5331
 
5332
  /* Layout the class itself.  */
5333
  layout_class_type (t, &virtuals);
5334
  if (CLASSTYPE_AS_BASE (t) != t)
5335
    /* We use the base type for trivial assignments, and hence it
5336
       needs a mode.  */
5337
    compute_record_mode (CLASSTYPE_AS_BASE (t));
5338
 
5339
  virtuals = modify_all_vtables (t, nreverse (virtuals));
5340
 
5341
  /* If necessary, create the primary vtable for this class.  */
5342
  if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5343
    {
5344
      /* We must enter these virtuals into the table.  */
5345
      if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5346
        build_primary_vtable (NULL_TREE, t);
5347
      else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5348
        /* Here we know enough to change the type of our virtual
5349
           function table, but we will wait until later this function.  */
5350
        build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5351
    }
5352
 
5353
  if (TYPE_CONTAINS_VPTR_P (t))
5354
    {
5355
      int vindex;
5356
      tree fn;
5357
 
5358
      if (BINFO_VTABLE (TYPE_BINFO (t)))
5359
        gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5360
      if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5361
        gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5362
 
5363
      /* Add entries for virtual functions introduced by this class.  */
5364
      BINFO_VIRTUALS (TYPE_BINFO (t))
5365
        = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5366
 
5367
      /* Set DECL_VINDEX for all functions declared in this class.  */
5368
      for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5369
           fn;
5370
           fn = TREE_CHAIN (fn),
5371
             vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5372
                        ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5373
        {
5374
          tree fndecl = BV_FN (fn);
5375
 
5376
          if (DECL_THUNK_P (fndecl))
5377
            /* A thunk. We should never be calling this entry directly
5378
               from this vtable -- we'd use the entry for the non
5379
               thunk base function.  */
5380
            DECL_VINDEX (fndecl) = NULL_TREE;
5381
          else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5382
            DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5383
        }
5384
    }
5385
 
5386
  finish_struct_bits (t);
5387
 
5388
  /* Complete the rtl for any static member objects of the type we're
5389
     working on.  */
5390
  for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5391
    if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5392
        && TREE_TYPE (x) != error_mark_node
5393
        && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5394
      DECL_MODE (x) = TYPE_MODE (t);
5395
 
5396
  /* Done with FIELDS...now decide whether to sort these for
5397
     faster lookups later.
5398
 
5399
     We use a small number because most searches fail (succeeding
5400
     ultimately as the search bores through the inheritance
5401
     hierarchy), and we want this failure to occur quickly.  */
5402
 
5403
  n_fields = count_fields (TYPE_FIELDS (t));
5404
  if (n_fields > 7)
5405
    {
5406
      struct sorted_fields_type *field_vec = GGC_NEWVAR
5407
         (struct sorted_fields_type,
5408
          sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5409
      field_vec->len = n_fields;
5410
      add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5411
      qsort (field_vec->elts, n_fields, sizeof (tree),
5412
             field_decl_cmp);
5413
      CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5414
    }
5415
 
5416
  /* Complain if one of the field types requires lower visibility.  */
5417
  constrain_class_visibility (t);
5418
 
5419
  /* Make the rtl for any new vtables we have created, and unmark
5420
     the base types we marked.  */
5421
  finish_vtbls (t);
5422
 
5423
  /* Build the VTT for T.  */
5424
  build_vtt (t);
5425
 
5426
  /* This warning does not make sense for Java classes, since they
5427
     cannot have destructors.  */
5428
  if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5429
    {
5430
      tree dtor;
5431
 
5432
      dtor = CLASSTYPE_DESTRUCTORS (t);
5433
      if (/* An implicitly declared destructor is always public.  And,
5434
             if it were virtual, we would have created it by now.  */
5435
          !dtor
5436
          || (!DECL_VINDEX (dtor)
5437
              && (/* public non-virtual */
5438
                  (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5439
                   || (/* non-public non-virtual with friends */
5440
                       (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5441
                        && (CLASSTYPE_FRIEND_CLASSES (t)
5442
                        || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5443
        warning (OPT_Wnon_virtual_dtor,
5444
                 "%q#T has virtual functions and accessible"
5445
                 " non-virtual destructor", t);
5446
    }
5447
 
5448
  complete_vars (t);
5449
 
5450
  if (warn_overloaded_virtual)
5451
    warn_hidden (t);
5452
 
5453
  /* Class layout, assignment of virtual table slots, etc., is now
5454
     complete.  Give the back end a chance to tweak the visibility of
5455
     the class or perform any other required target modifications.  */
5456
  targetm.cxx.adjust_class_at_definition (t);
5457
 
5458
  maybe_suppress_debug_info (t);
5459
 
5460
  dump_class_hierarchy (t);
5461
 
5462
  /* Finish debugging output for this type.  */
5463
  rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5464
}
5465
 
5466
/* When T was built up, the member declarations were added in reverse
5467
   order.  Rearrange them to declaration order.  */
5468
 
5469
void
5470
unreverse_member_declarations (tree t)
5471
{
5472
  tree next;
5473
  tree prev;
5474
  tree x;
5475
 
5476
  /* The following lists are all in reverse order.  Put them in
5477
     declaration order now.  */
5478
  TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5479
  CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5480
 
5481
  /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5482
     reverse order, so we can't just use nreverse.  */
5483
  prev = NULL_TREE;
5484
  for (x = TYPE_FIELDS (t);
5485
       x && TREE_CODE (x) != TYPE_DECL;
5486
       x = next)
5487
    {
5488
      next = TREE_CHAIN (x);
5489
      TREE_CHAIN (x) = prev;
5490
      prev = x;
5491
    }
5492
  if (prev)
5493
    {
5494
      TREE_CHAIN (TYPE_FIELDS (t)) = x;
5495
      if (prev)
5496
        TYPE_FIELDS (t) = prev;
5497
    }
5498
}
5499
 
5500
tree
5501
finish_struct (tree t, tree attributes)
5502
{
5503
  location_t saved_loc = input_location;
5504
 
5505
  /* Now that we've got all the field declarations, reverse everything
5506
     as necessary.  */
5507
  unreverse_member_declarations (t);
5508
 
5509
  cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5510
 
5511
  /* Nadger the current location so that diagnostics point to the start of
5512
     the struct, not the end.  */
5513
  input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5514
 
5515
  if (processing_template_decl)
5516
    {
5517
      tree x;
5518
 
5519
      finish_struct_methods (t);
5520
      TYPE_SIZE (t) = bitsize_zero_node;
5521
      TYPE_SIZE_UNIT (t) = size_zero_node;
5522
 
5523
      /* We need to emit an error message if this type was used as a parameter
5524
         and it is an abstract type, even if it is a template. We construct
5525
         a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5526
         account and we call complete_vars with this type, which will check
5527
         the PARM_DECLS. Note that while the type is being defined,
5528
         CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5529
         (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it.  */
5530
      CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5531
      for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5532
        if (DECL_PURE_VIRTUAL_P (x))
5533
          VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5534
      complete_vars (t);
5535
 
5536
      /* Remember current #pragma pack value.  */
5537
      TYPE_PRECISION (t) = maximum_field_alignment;
5538
    }
5539
  else
5540
    finish_struct_1 (t);
5541
 
5542
  input_location = saved_loc;
5543
 
5544
  TYPE_BEING_DEFINED (t) = 0;
5545
 
5546
  if (current_class_type)
5547
    popclass ();
5548
  else
5549
    error ("trying to finish struct, but kicked out due to previous parse errors");
5550
 
5551
  if (processing_template_decl && at_function_scope_p ())
5552
    add_stmt (build_min (TAG_DEFN, t));
5553
 
5554
  return t;
5555
}
5556
 
5557
/* Return the dynamic type of INSTANCE, if known.
5558
   Used to determine whether the virtual function table is needed
5559
   or not.
5560
 
5561
   *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5562
   of our knowledge of its type.  *NONNULL should be initialized
5563
   before this function is called.  */
5564
 
5565
static tree
5566
fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5567
{
5568
#define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5569
 
5570
  switch (TREE_CODE (instance))
5571
    {
5572
    case INDIRECT_REF:
5573
      if (POINTER_TYPE_P (TREE_TYPE (instance)))
5574
        return NULL_TREE;
5575
      else
5576
        return RECUR (TREE_OPERAND (instance, 0));
5577
 
5578
    case CALL_EXPR:
5579
      /* This is a call to a constructor, hence it's never zero.  */
5580
      if (TREE_HAS_CONSTRUCTOR (instance))
5581
        {
5582
          if (nonnull)
5583
            *nonnull = 1;
5584
          return TREE_TYPE (instance);
5585
        }
5586
      return NULL_TREE;
5587
 
5588
    case SAVE_EXPR:
5589
      /* This is a call to a constructor, hence it's never zero.  */
5590
      if (TREE_HAS_CONSTRUCTOR (instance))
5591
        {
5592
          if (nonnull)
5593
            *nonnull = 1;
5594
          return TREE_TYPE (instance);
5595
        }
5596
      return RECUR (TREE_OPERAND (instance, 0));
5597
 
5598
    case POINTER_PLUS_EXPR:
5599
    case PLUS_EXPR:
5600
    case MINUS_EXPR:
5601
      if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5602
        return RECUR (TREE_OPERAND (instance, 0));
5603
      if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5604
        /* Propagate nonnull.  */
5605
        return RECUR (TREE_OPERAND (instance, 0));
5606
 
5607
      return NULL_TREE;
5608
 
5609
    CASE_CONVERT:
5610
      return RECUR (TREE_OPERAND (instance, 0));
5611
 
5612
    case ADDR_EXPR:
5613
      instance = TREE_OPERAND (instance, 0);
5614
      if (nonnull)
5615
        {
5616
          /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5617
             with a real object -- given &p->f, p can still be null.  */
5618
          tree t = get_base_address (instance);
5619
          /* ??? Probably should check DECL_WEAK here.  */
5620
          if (t && DECL_P (t))
5621
            *nonnull = 1;
5622
        }
5623
      return RECUR (instance);
5624
 
5625
    case COMPONENT_REF:
5626
      /* If this component is really a base class reference, then the field
5627
         itself isn't definitive.  */
5628
      if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5629
        return RECUR (TREE_OPERAND (instance, 0));
5630
      return RECUR (TREE_OPERAND (instance, 1));
5631
 
5632
    case VAR_DECL:
5633
    case FIELD_DECL:
5634
      if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5635
          && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5636
        {
5637
          if (nonnull)
5638
            *nonnull = 1;
5639
          return TREE_TYPE (TREE_TYPE (instance));
5640
        }
5641
      /* fall through...  */
5642
    case TARGET_EXPR:
5643
    case PARM_DECL:
5644
    case RESULT_DECL:
5645
      if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5646
        {
5647
          if (nonnull)
5648
            *nonnull = 1;
5649
          return TREE_TYPE (instance);
5650
        }
5651
      else if (instance == current_class_ptr)
5652
        {
5653
          if (nonnull)
5654
            *nonnull = 1;
5655
 
5656
          /* if we're in a ctor or dtor, we know our type.  */
5657
          if (DECL_LANG_SPECIFIC (current_function_decl)
5658
              && (DECL_CONSTRUCTOR_P (current_function_decl)
5659
                  || DECL_DESTRUCTOR_P (current_function_decl)))
5660
            {
5661
              if (cdtorp)
5662
                *cdtorp = 1;
5663
              return TREE_TYPE (TREE_TYPE (instance));
5664
            }
5665
        }
5666
      else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5667
        {
5668
          /* We only need one hash table because it is always left empty.  */
5669
          static htab_t ht;
5670
          if (!ht)
5671
            ht = htab_create (37,
5672
                              htab_hash_pointer,
5673
                              htab_eq_pointer,
5674
                              /*htab_del=*/NULL);
5675
 
5676
          /* Reference variables should be references to objects.  */
5677
          if (nonnull)
5678
            *nonnull = 1;
5679
 
5680
          /* Enter the INSTANCE in a table to prevent recursion; a
5681
             variable's initializer may refer to the variable
5682
             itself.  */
5683
          if (TREE_CODE (instance) == VAR_DECL
5684
              && DECL_INITIAL (instance)
5685
              && !htab_find (ht, instance))
5686
            {
5687
              tree type;
5688
              void **slot;
5689
 
5690
              slot = htab_find_slot (ht, instance, INSERT);
5691
              *slot = instance;
5692
              type = RECUR (DECL_INITIAL (instance));
5693
              htab_remove_elt (ht, instance);
5694
 
5695
              return type;
5696
            }
5697
        }
5698
      return NULL_TREE;
5699
 
5700
    default:
5701
      return NULL_TREE;
5702
    }
5703
#undef RECUR
5704
}
5705
 
5706
/* Return nonzero if the dynamic type of INSTANCE is known, and
5707
   equivalent to the static type.  We also handle the case where
5708
   INSTANCE is really a pointer. Return negative if this is a
5709
   ctor/dtor. There the dynamic type is known, but this might not be
5710
   the most derived base of the original object, and hence virtual
5711
   bases may not be layed out according to this type.
5712
 
5713
   Used to determine whether the virtual function table is needed
5714
   or not.
5715
 
5716
   *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5717
   of our knowledge of its type.  *NONNULL should be initialized
5718
   before this function is called.  */
5719
 
5720
int
5721
resolves_to_fixed_type_p (tree instance, int* nonnull)
5722
{
5723
  tree t = TREE_TYPE (instance);
5724
  int cdtorp = 0;
5725
  tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5726
  if (fixed == NULL_TREE)
5727
    return 0;
5728
  if (POINTER_TYPE_P (t))
5729
    t = TREE_TYPE (t);
5730
  if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5731
    return 0;
5732
  return cdtorp ? -1 : 1;
5733
}
5734
 
5735
 
5736
void
5737
init_class_processing (void)
5738
{
5739
  current_class_depth = 0;
5740
  current_class_stack_size = 10;
5741
  current_class_stack
5742
    = XNEWVEC (struct class_stack_node, current_class_stack_size);
5743
  local_classes = VEC_alloc (tree, gc, 8);
5744
  sizeof_biggest_empty_class = size_zero_node;
5745
 
5746
  ridpointers[(int) RID_PUBLIC] = access_public_node;
5747
  ridpointers[(int) RID_PRIVATE] = access_private_node;
5748
  ridpointers[(int) RID_PROTECTED] = access_protected_node;
5749
}
5750
 
5751
/* Restore the cached PREVIOUS_CLASS_LEVEL.  */
5752
 
5753
static void
5754
restore_class_cache (void)
5755
{
5756
  tree type;
5757
 
5758
  /* We are re-entering the same class we just left, so we don't
5759
     have to search the whole inheritance matrix to find all the
5760
     decls to bind again.  Instead, we install the cached
5761
     class_shadowed list and walk through it binding names.  */
5762
  push_binding_level (previous_class_level);
5763
  class_binding_level = previous_class_level;
5764
  /* Restore IDENTIFIER_TYPE_VALUE.  */
5765
  for (type = class_binding_level->type_shadowed;
5766
       type;
5767
       type = TREE_CHAIN (type))
5768
    SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5769
}
5770
 
5771
/* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5772
   appropriate for TYPE.
5773
 
5774
   So that we may avoid calls to lookup_name, we cache the _TYPE
5775
   nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5776
 
5777
   For multiple inheritance, we perform a two-pass depth-first search
5778
   of the type lattice.  */
5779
 
5780
void
5781
pushclass (tree type)
5782
{
5783
  class_stack_node_t csn;
5784
 
5785
  type = TYPE_MAIN_VARIANT (type);
5786
 
5787
  /* Make sure there is enough room for the new entry on the stack.  */
5788
  if (current_class_depth + 1 >= current_class_stack_size)
5789
    {
5790
      current_class_stack_size *= 2;
5791
      current_class_stack
5792
        = XRESIZEVEC (struct class_stack_node, current_class_stack,
5793
                      current_class_stack_size);
5794
    }
5795
 
5796
  /* Insert a new entry on the class stack.  */
5797
  csn = current_class_stack + current_class_depth;
5798
  csn->name = current_class_name;
5799
  csn->type = current_class_type;
5800
  csn->access = current_access_specifier;
5801
  csn->names_used = 0;
5802
  csn->hidden = 0;
5803
  current_class_depth++;
5804
 
5805
  /* Now set up the new type.  */
5806
  current_class_name = TYPE_NAME (type);
5807
  if (TREE_CODE (current_class_name) == TYPE_DECL)
5808
    current_class_name = DECL_NAME (current_class_name);
5809
  current_class_type = type;
5810
 
5811
  /* By default, things in classes are private, while things in
5812
     structures or unions are public.  */
5813
  current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5814
                              ? access_private_node
5815
                              : access_public_node);
5816
 
5817
  if (previous_class_level
5818
      && type != previous_class_level->this_entity
5819
      && current_class_depth == 1)
5820
    {
5821
      /* Forcibly remove any old class remnants.  */
5822
      invalidate_class_lookup_cache ();
5823
    }
5824
 
5825
  if (!previous_class_level
5826
      || type != previous_class_level->this_entity
5827
      || current_class_depth > 1)
5828
    pushlevel_class ();
5829
  else
5830
    restore_class_cache ();
5831
}
5832
 
5833
/* When we exit a toplevel class scope, we save its binding level so
5834
   that we can restore it quickly.  Here, we've entered some other
5835
   class, so we must invalidate our cache.  */
5836
 
5837
void
5838
invalidate_class_lookup_cache (void)
5839
{
5840
  previous_class_level = NULL;
5841
}
5842
 
5843
/* Get out of the current class scope. If we were in a class scope
5844
   previously, that is the one popped to.  */
5845
 
5846
void
5847
popclass (void)
5848
{
5849
  poplevel_class ();
5850
 
5851
  current_class_depth--;
5852
  current_class_name = current_class_stack[current_class_depth].name;
5853
  current_class_type = current_class_stack[current_class_depth].type;
5854
  current_access_specifier = current_class_stack[current_class_depth].access;
5855
  if (current_class_stack[current_class_depth].names_used)
5856
    splay_tree_delete (current_class_stack[current_class_depth].names_used);
5857
}
5858
 
5859
/* Mark the top of the class stack as hidden.  */
5860
 
5861
void
5862
push_class_stack (void)
5863
{
5864
  if (current_class_depth)
5865
    ++current_class_stack[current_class_depth - 1].hidden;
5866
}
5867
 
5868
/* Mark the top of the class stack as un-hidden.  */
5869
 
5870
void
5871
pop_class_stack (void)
5872
{
5873
  if (current_class_depth)
5874
    --current_class_stack[current_class_depth - 1].hidden;
5875
}
5876
 
5877
/* Returns 1 if the class type currently being defined is either T or
5878
   a nested type of T.  */
5879
 
5880
bool
5881
currently_open_class (tree t)
5882
{
5883
  int i;
5884
 
5885
  if (!CLASS_TYPE_P (t))
5886
    return false;
5887
 
5888
  t = TYPE_MAIN_VARIANT (t);
5889
 
5890
  /* We start looking from 1 because entry 0 is from global scope,
5891
     and has no type.  */
5892
  for (i = current_class_depth; i > 0; --i)
5893
    {
5894
      tree c;
5895
      if (i == current_class_depth)
5896
        c = current_class_type;
5897
      else
5898
        {
5899
          if (current_class_stack[i].hidden)
5900
            break;
5901
          c = current_class_stack[i].type;
5902
        }
5903
      if (!c)
5904
        continue;
5905
      if (same_type_p (c, t))
5906
        return true;
5907
    }
5908
  return false;
5909
}
5910
 
5911
/* If either current_class_type or one of its enclosing classes are derived
5912
   from T, return the appropriate type.  Used to determine how we found
5913
   something via unqualified lookup.  */
5914
 
5915
tree
5916
currently_open_derived_class (tree t)
5917
{
5918
  int i;
5919
 
5920
  /* The bases of a dependent type are unknown.  */
5921
  if (dependent_type_p (t))
5922
    return NULL_TREE;
5923
 
5924
  if (!current_class_type)
5925
    return NULL_TREE;
5926
 
5927
  if (DERIVED_FROM_P (t, current_class_type))
5928
    return current_class_type;
5929
 
5930
  for (i = current_class_depth - 1; i > 0; --i)
5931
    {
5932
      if (current_class_stack[i].hidden)
5933
        break;
5934
      if (DERIVED_FROM_P (t, current_class_stack[i].type))
5935
        return current_class_stack[i].type;
5936
    }
5937
 
5938
  return NULL_TREE;
5939
}
5940
 
5941
/* When entering a class scope, all enclosing class scopes' names with
5942
   static meaning (static variables, static functions, types and
5943
   enumerators) have to be visible.  This recursive function calls
5944
   pushclass for all enclosing class contexts until global or a local
5945
   scope is reached.  TYPE is the enclosed class.  */
5946
 
5947
void
5948
push_nested_class (tree type)
5949
{
5950
  /* A namespace might be passed in error cases, like A::B:C.  */
5951
  if (type == NULL_TREE
5952
      || !CLASS_TYPE_P (type))
5953
    return;
5954
 
5955
  push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
5956
 
5957
  pushclass (type);
5958
}
5959
 
5960
/* Undoes a push_nested_class call.  */
5961
 
5962
void
5963
pop_nested_class (void)
5964
{
5965
  tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5966
 
5967
  popclass ();
5968
  if (context && CLASS_TYPE_P (context))
5969
    pop_nested_class ();
5970
}
5971
 
5972
/* Returns the number of extern "LANG" blocks we are nested within.  */
5973
 
5974
int
5975
current_lang_depth (void)
5976
{
5977
  return VEC_length (tree, current_lang_base);
5978
}
5979
 
5980
/* Set global variables CURRENT_LANG_NAME to appropriate value
5981
   so that behavior of name-mangling machinery is correct.  */
5982
 
5983
void
5984
push_lang_context (tree name)
5985
{
5986
  VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5987
 
5988
  if (name == lang_name_cplusplus)
5989
    {
5990
      current_lang_name = name;
5991
    }
5992
  else if (name == lang_name_java)
5993
    {
5994
      current_lang_name = name;
5995
      /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5996
         (See record_builtin_java_type in decl.c.)  However, that causes
5997
         incorrect debug entries if these types are actually used.
5998
         So we re-enable debug output after extern "Java".  */
5999
      DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6000
      DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6001
      DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6002
      DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6003
      DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6004
      DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6005
      DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6006
      DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6007
    }
6008
  else if (name == lang_name_c)
6009
    {
6010
      current_lang_name = name;
6011
    }
6012
  else
6013
    error ("language string %<\"%E\"%> not recognized", name);
6014
}
6015
 
6016
/* Get out of the current language scope.  */
6017
 
6018
void
6019
pop_lang_context (void)
6020
{
6021
  current_lang_name = VEC_pop (tree, current_lang_base);
6022
}
6023
 
6024
/* Type instantiation routines.  */
6025
 
6026
/* Given an OVERLOAD and a TARGET_TYPE, return the function that
6027
   matches the TARGET_TYPE.  If there is no satisfactory match, return
6028
   error_mark_node, and issue an error & warning messages under
6029
   control of FLAGS.  Permit pointers to member function if FLAGS
6030
   permits.  If TEMPLATE_ONLY, the name of the overloaded function was
6031
   a template-id, and EXPLICIT_TARGS are the explicitly provided
6032
   template arguments.
6033
 
6034
   If OVERLOAD is for one or more member functions, then ACCESS_PATH
6035
   is the base path used to reference those member functions.  If
6036
   TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6037
   resolved to a member function, access checks will be performed and
6038
   errors issued if appropriate.  */
6039
 
6040
static tree
6041
resolve_address_of_overloaded_function (tree target_type,
6042
                                        tree overload,
6043
                                        tsubst_flags_t flags,
6044
                                        bool template_only,
6045
                                        tree explicit_targs,
6046
                                        tree access_path)
6047
{
6048
  /* Here's what the standard says:
6049
 
6050
       [over.over]
6051
 
6052
       If the name is a function template, template argument deduction
6053
       is done, and if the argument deduction succeeds, the deduced
6054
       arguments are used to generate a single template function, which
6055
       is added to the set of overloaded functions considered.
6056
 
6057
       Non-member functions and static member functions match targets of
6058
       type "pointer-to-function" or "reference-to-function."  Nonstatic
6059
       member functions match targets of type "pointer-to-member
6060
       function;" the function type of the pointer to member is used to
6061
       select the member function from the set of overloaded member
6062
       functions.  If a nonstatic member function is selected, the
6063
       reference to the overloaded function name is required to have the
6064
       form of a pointer to member as described in 5.3.1.
6065
 
6066
       If more than one function is selected, any template functions in
6067
       the set are eliminated if the set also contains a non-template
6068
       function, and any given template function is eliminated if the
6069
       set contains a second template function that is more specialized
6070
       than the first according to the partial ordering rules 14.5.5.2.
6071
       After such eliminations, if any, there shall remain exactly one
6072
       selected function.  */
6073
 
6074
  int is_ptrmem = 0;
6075
  /* We store the matches in a TREE_LIST rooted here.  The functions
6076
     are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6077
     interoperability with most_specialized_instantiation.  */
6078
  tree matches = NULL_TREE;
6079
  tree fn;
6080
  tree target_fn_type;
6081
 
6082
  /* By the time we get here, we should be seeing only real
6083
     pointer-to-member types, not the internal POINTER_TYPE to
6084
     METHOD_TYPE representation.  */
6085
  gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6086
              || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6087
 
6088
  gcc_assert (is_overloaded_fn (overload));
6089
 
6090
  /* Check that the TARGET_TYPE is reasonable.  */
6091
  if (TYPE_PTRFN_P (target_type))
6092
    /* This is OK.  */;
6093
  else if (TYPE_PTRMEMFUNC_P (target_type))
6094
    /* This is OK, too.  */
6095
    is_ptrmem = 1;
6096
  else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6097
    /* This is OK, too.  This comes from a conversion to reference
6098
       type.  */
6099
    target_type = build_reference_type (target_type);
6100
  else
6101
    {
6102
      if (flags & tf_error)
6103
        error ("cannot resolve overloaded function %qD based on"
6104
               " conversion to type %qT",
6105
               DECL_NAME (OVL_FUNCTION (overload)), target_type);
6106
      return error_mark_node;
6107
    }
6108
 
6109
  /* Non-member functions and static member functions match targets of type
6110
     "pointer-to-function" or "reference-to-function."  Nonstatic member
6111
     functions match targets of type "pointer-to-member-function;" the
6112
     function type of the pointer to member is used to select the member
6113
     function from the set of overloaded member functions.
6114
 
6115
     So figure out the FUNCTION_TYPE that we want to match against.  */
6116
  target_fn_type = static_fn_type (target_type);
6117
 
6118
  /* If we can find a non-template function that matches, we can just
6119
     use it.  There's no point in generating template instantiations
6120
     if we're just going to throw them out anyhow.  But, of course, we
6121
     can only do this when we don't *need* a template function.  */
6122
  if (!template_only)
6123
    {
6124
      tree fns;
6125
 
6126
      for (fns = overload; fns; fns = OVL_NEXT (fns))
6127
        {
6128
          tree fn = OVL_CURRENT (fns);
6129
 
6130
          if (TREE_CODE (fn) == TEMPLATE_DECL)
6131
            /* We're not looking for templates just yet.  */
6132
            continue;
6133
 
6134
          if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6135
              != is_ptrmem)
6136
            /* We're looking for a non-static member, and this isn't
6137
               one, or vice versa.  */
6138
            continue;
6139
 
6140
          /* Ignore functions which haven't been explicitly
6141
             declared.  */
6142
          if (DECL_ANTICIPATED (fn))
6143
            continue;
6144
 
6145
          /* See if there's a match.  */
6146
          if (same_type_p (target_fn_type, static_fn_type (fn)))
6147
            matches = tree_cons (fn, NULL_TREE, matches);
6148
        }
6149
    }
6150
 
6151
  /* Now, if we've already got a match (or matches), there's no need
6152
     to proceed to the template functions.  But, if we don't have a
6153
     match we need to look at them, too.  */
6154
  if (!matches)
6155
    {
6156
      tree target_arg_types;
6157
      tree target_ret_type;
6158
      tree fns;
6159
      tree *args;
6160
      unsigned int nargs, ia;
6161
      tree arg;
6162
 
6163
      target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6164
      target_ret_type = TREE_TYPE (target_fn_type);
6165
 
6166
      nargs = list_length (target_arg_types);
6167
      args = XALLOCAVEC (tree, nargs);
6168
      for (arg = target_arg_types, ia = 0;
6169
           arg != NULL_TREE && arg != void_list_node;
6170
           arg = TREE_CHAIN (arg), ++ia)
6171
        args[ia] = TREE_VALUE (arg);
6172
      nargs = ia;
6173
 
6174
      for (fns = overload; fns; fns = OVL_NEXT (fns))
6175
        {
6176
          tree fn = OVL_CURRENT (fns);
6177
          tree instantiation;
6178
          tree targs;
6179
 
6180
          if (TREE_CODE (fn) != TEMPLATE_DECL)
6181
            /* We're only looking for templates.  */
6182
            continue;
6183
 
6184
          if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6185
              != is_ptrmem)
6186
            /* We're not looking for a non-static member, and this is
6187
               one, or vice versa.  */
6188
            continue;
6189
 
6190
          /* Try to do argument deduction.  */
6191
          targs = make_tree_vec (DECL_NTPARMS (fn));
6192
          if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6193
                                   target_ret_type, DEDUCE_EXACT,
6194
                                   LOOKUP_NORMAL))
6195
            /* Argument deduction failed.  */
6196
            continue;
6197
 
6198
          /* Instantiate the template.  */
6199
          instantiation = instantiate_template (fn, targs, flags);
6200
          if (instantiation == error_mark_node)
6201
            /* Instantiation failed.  */
6202
            continue;
6203
 
6204
          /* See if there's a match.  */
6205
          if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6206
            matches = tree_cons (instantiation, fn, matches);
6207
        }
6208
 
6209
      /* Now, remove all but the most specialized of the matches.  */
6210
      if (matches)
6211
        {
6212
          tree match = most_specialized_instantiation (matches);
6213
 
6214
          if (match != error_mark_node)
6215
            matches = tree_cons (TREE_PURPOSE (match),
6216
                                 NULL_TREE,
6217
                                 NULL_TREE);
6218
        }
6219
    }
6220
 
6221
  /* Now we should have exactly one function in MATCHES.  */
6222
  if (matches == NULL_TREE)
6223
    {
6224
      /* There were *no* matches.  */
6225
      if (flags & tf_error)
6226
        {
6227
          error ("no matches converting function %qD to type %q#T",
6228
                 DECL_NAME (OVL_CURRENT (overload)),
6229
                 target_type);
6230
 
6231
          /* print_candidates expects a chain with the functions in
6232
             TREE_VALUE slots, so we cons one up here (we're losing anyway,
6233
             so why be clever?).  */
6234
          for (; overload; overload = OVL_NEXT (overload))
6235
            matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6236
                                 matches);
6237
 
6238
          print_candidates (matches);
6239
        }
6240
      return error_mark_node;
6241
    }
6242
  else if (TREE_CHAIN (matches))
6243
    {
6244
      /* There were too many matches.  First check if they're all
6245
         the same function.  */
6246
      tree match;
6247
 
6248
      fn = TREE_PURPOSE (matches);
6249
      for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6250
        if (!decls_match (fn, TREE_PURPOSE (match)))
6251
          break;
6252
 
6253
      if (match)
6254
        {
6255
          if (flags & tf_error)
6256
            {
6257
              error ("converting overloaded function %qD to type %q#T is ambiguous",
6258
                     DECL_NAME (OVL_FUNCTION (overload)),
6259
                     target_type);
6260
 
6261
              /* Since print_candidates expects the functions in the
6262
                 TREE_VALUE slot, we flip them here.  */
6263
              for (match = matches; match; match = TREE_CHAIN (match))
6264
                TREE_VALUE (match) = TREE_PURPOSE (match);
6265
 
6266
              print_candidates (matches);
6267
            }
6268
 
6269
          return error_mark_node;
6270
        }
6271
    }
6272
 
6273
  /* Good, exactly one match.  Now, convert it to the correct type.  */
6274
  fn = TREE_PURPOSE (matches);
6275
 
6276
  if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6277
      && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6278
    {
6279
      static int explained;
6280
 
6281
      if (!(flags & tf_error))
6282
        return error_mark_node;
6283
 
6284
      permerror (input_location, "assuming pointer to member %qD", fn);
6285
      if (!explained)
6286
        {
6287
          inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6288
          explained = 1;
6289
        }
6290
    }
6291
 
6292
  /* If we're doing overload resolution purely for the purpose of
6293
     determining conversion sequences, we should not consider the
6294
     function used.  If this conversion sequence is selected, the
6295
     function will be marked as used at this point.  */
6296
  if (!(flags & tf_conv))
6297
    {
6298
      /* Make =delete work with SFINAE.  */
6299
      if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6300
        return error_mark_node;
6301
 
6302
      mark_used (fn);
6303
    }
6304
 
6305
  /* We could not check access to member functions when this
6306
     expression was originally created since we did not know at that
6307
     time to which function the expression referred.  */
6308
  if (!(flags & tf_no_access_control)
6309
      && DECL_FUNCTION_MEMBER_P (fn))
6310
    {
6311
      gcc_assert (access_path);
6312
      perform_or_defer_access_check (access_path, fn, fn);
6313
    }
6314
 
6315
  if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6316
    return cp_build_unary_op (ADDR_EXPR, fn, 0, flags);
6317
  else
6318
    {
6319
      /* The target must be a REFERENCE_TYPE.  Above, cp_build_unary_op
6320
         will mark the function as addressed, but here we must do it
6321
         explicitly.  */
6322
      cxx_mark_addressable (fn);
6323
 
6324
      return fn;
6325
    }
6326
}
6327
 
6328
/* This function will instantiate the type of the expression given in
6329
   RHS to match the type of LHSTYPE.  If errors exist, then return
6330
   error_mark_node. FLAGS is a bit mask.  If TF_ERROR is set, then
6331
   we complain on errors.  If we are not complaining, never modify rhs,
6332
   as overload resolution wants to try many possible instantiations, in
6333
   the hope that at least one will work.
6334
 
6335
   For non-recursive calls, LHSTYPE should be a function, pointer to
6336
   function, or a pointer to member function.  */
6337
 
6338
tree
6339
instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6340
{
6341
  tsubst_flags_t flags_in = flags;
6342
  tree access_path = NULL_TREE;
6343
 
6344
  flags &= ~tf_ptrmem_ok;
6345
 
6346
  if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6347
    {
6348
      if (flags & tf_error)
6349
        error ("not enough type information");
6350
      return error_mark_node;
6351
    }
6352
 
6353
  if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6354
    {
6355
      if (same_type_p (lhstype, TREE_TYPE (rhs)))
6356
        return rhs;
6357
      if (flag_ms_extensions
6358
          && TYPE_PTRMEMFUNC_P (lhstype)
6359
          && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6360
        /* Microsoft allows `A::f' to be resolved to a
6361
           pointer-to-member.  */
6362
        ;
6363
      else
6364
        {
6365
          if (flags & tf_error)
6366
            error ("argument of type %qT does not match %qT",
6367
                   TREE_TYPE (rhs), lhstype);
6368
          return error_mark_node;
6369
        }
6370
    }
6371
 
6372
  if (TREE_CODE (rhs) == BASELINK)
6373
    {
6374
      access_path = BASELINK_ACCESS_BINFO (rhs);
6375
      rhs = BASELINK_FUNCTIONS (rhs);
6376
    }
6377
 
6378
  /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6379
     deduce any type information.  */
6380
  if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6381
    {
6382
      if (flags & tf_error)
6383
        error ("not enough type information");
6384
      return error_mark_node;
6385
    }
6386
 
6387
  /* There only a few kinds of expressions that may have a type
6388
     dependent on overload resolution.  */
6389
  gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6390
              || TREE_CODE (rhs) == COMPONENT_REF
6391
              || really_overloaded_fn (rhs)
6392
              || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6393
 
6394
  /* This should really only be used when attempting to distinguish
6395
     what sort of a pointer to function we have.  For now, any
6396
     arithmetic operation which is not supported on pointers
6397
     is rejected as an error.  */
6398
 
6399
  switch (TREE_CODE (rhs))
6400
    {
6401
    case COMPONENT_REF:
6402
      {
6403
        tree member = TREE_OPERAND (rhs, 1);
6404
 
6405
        member = instantiate_type (lhstype, member, flags);
6406
        if (member != error_mark_node
6407
            && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6408
          /* Do not lose object's side effects.  */
6409
          return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6410
                         TREE_OPERAND (rhs, 0), member);
6411
        return member;
6412
      }
6413
 
6414
    case OFFSET_REF:
6415
      rhs = TREE_OPERAND (rhs, 1);
6416
      if (BASELINK_P (rhs))
6417
        return instantiate_type (lhstype, rhs, flags_in);
6418
 
6419
      /* This can happen if we are forming a pointer-to-member for a
6420
         member template.  */
6421
      gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6422
 
6423
      /* Fall through.  */
6424
 
6425
    case TEMPLATE_ID_EXPR:
6426
      {
6427
        tree fns = TREE_OPERAND (rhs, 0);
6428
        tree args = TREE_OPERAND (rhs, 1);
6429
 
6430
        return
6431
          resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6432
                                                  /*template_only=*/true,
6433
                                                  args, access_path);
6434
      }
6435
 
6436
    case OVERLOAD:
6437
    case FUNCTION_DECL:
6438
      return
6439
        resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6440
                                                /*template_only=*/false,
6441
                                                /*explicit_targs=*/NULL_TREE,
6442
                                                access_path);
6443
 
6444
    case ADDR_EXPR:
6445
    {
6446
      if (PTRMEM_OK_P (rhs))
6447
        flags |= tf_ptrmem_ok;
6448
 
6449
      return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6450
    }
6451
 
6452
    case ERROR_MARK:
6453
      return error_mark_node;
6454
 
6455
    default:
6456
      gcc_unreachable ();
6457
    }
6458
  return error_mark_node;
6459
}
6460
 
6461
/* Return the name of the virtual function pointer field
6462
   (as an IDENTIFIER_NODE) for the given TYPE.  Note that
6463
   this may have to look back through base types to find the
6464
   ultimate field name.  (For single inheritance, these could
6465
   all be the same name.  Who knows for multiple inheritance).  */
6466
 
6467
static tree
6468
get_vfield_name (tree type)
6469
{
6470
  tree binfo, base_binfo;
6471
  char *buf;
6472
 
6473
  for (binfo = TYPE_BINFO (type);
6474
       BINFO_N_BASE_BINFOS (binfo);
6475
       binfo = base_binfo)
6476
    {
6477
      base_binfo = BINFO_BASE_BINFO (binfo, 0);
6478
 
6479
      if (BINFO_VIRTUAL_P (base_binfo)
6480
          || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6481
        break;
6482
    }
6483
 
6484
  type = BINFO_TYPE (binfo);
6485
  buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6486
                         + TYPE_NAME_LENGTH (type) + 2);
6487
  sprintf (buf, VFIELD_NAME_FORMAT,
6488
           IDENTIFIER_POINTER (constructor_name (type)));
6489
  return get_identifier (buf);
6490
}
6491
 
6492
void
6493
print_class_statistics (void)
6494
{
6495
#ifdef GATHER_STATISTICS
6496
  fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6497
  fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6498
  if (n_vtables)
6499
    {
6500
      fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6501
               n_vtables, n_vtable_searches);
6502
      fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6503
               n_vtable_entries, n_vtable_elems);
6504
    }
6505
#endif
6506
}
6507
 
6508
/* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6509
   according to [class]:
6510
                                          The class-name is also inserted
6511
   into  the scope of the class itself.  For purposes of access checking,
6512
   the inserted class name is treated as if it were a public member name.  */
6513
 
6514
void
6515
build_self_reference (void)
6516
{
6517
  tree name = constructor_name (current_class_type);
6518
  tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6519
  tree saved_cas;
6520
 
6521
  DECL_NONLOCAL (value) = 1;
6522
  DECL_CONTEXT (value) = current_class_type;
6523
  DECL_ARTIFICIAL (value) = 1;
6524
  SET_DECL_SELF_REFERENCE_P (value);
6525
  cp_set_underlying_type (value);
6526
 
6527
  if (processing_template_decl)
6528
    value = push_template_decl (value);
6529
 
6530
  saved_cas = current_access_specifier;
6531
  current_access_specifier = access_public_node;
6532
  finish_member_declaration (value);
6533
  current_access_specifier = saved_cas;
6534
}
6535
 
6536
/* Returns 1 if TYPE contains only padding bytes.  */
6537
 
6538
int
6539
is_empty_class (tree type)
6540
{
6541
  if (type == error_mark_node)
6542
    return 0;
6543
 
6544
  if (! CLASS_TYPE_P (type))
6545
    return 0;
6546
 
6547
  /* In G++ 3.2, whether or not a class was empty was determined by
6548
     looking at its size.  */
6549
  if (abi_version_at_least (2))
6550
    return CLASSTYPE_EMPTY_P (type);
6551
  else
6552
    return integer_zerop (CLASSTYPE_SIZE (type));
6553
}
6554
 
6555
/* Returns true if TYPE contains an empty class.  */
6556
 
6557
static bool
6558
contains_empty_class_p (tree type)
6559
{
6560
  if (is_empty_class (type))
6561
    return true;
6562
  if (CLASS_TYPE_P (type))
6563
    {
6564
      tree field;
6565
      tree binfo;
6566
      tree base_binfo;
6567
      int i;
6568
 
6569
      for (binfo = TYPE_BINFO (type), i = 0;
6570
           BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6571
        if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6572
          return true;
6573
      for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6574
        if (TREE_CODE (field) == FIELD_DECL
6575
            && !DECL_ARTIFICIAL (field)
6576
            && is_empty_class (TREE_TYPE (field)))
6577
          return true;
6578
    }
6579
  else if (TREE_CODE (type) == ARRAY_TYPE)
6580
    return contains_empty_class_p (TREE_TYPE (type));
6581
  return false;
6582
}
6583
 
6584
/* Returns true if TYPE contains no actual data, just various
6585
   possible combinations of empty classes.  */
6586
 
6587
bool
6588
is_really_empty_class (tree type)
6589
{
6590
  if (is_empty_class (type))
6591
    return true;
6592
  if (CLASS_TYPE_P (type))
6593
    {
6594
      tree field;
6595
      tree binfo;
6596
      tree base_binfo;
6597
      int i;
6598
 
6599
      for (binfo = TYPE_BINFO (type), i = 0;
6600
           BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6601
        if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6602
          return false;
6603
      for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6604
        if (TREE_CODE (field) == FIELD_DECL
6605
            && !DECL_ARTIFICIAL (field)
6606
            && !is_really_empty_class (TREE_TYPE (field)))
6607
          return false;
6608
      return true;
6609
    }
6610
  else if (TREE_CODE (type) == ARRAY_TYPE)
6611
    return is_really_empty_class (TREE_TYPE (type));
6612
  return false;
6613
}
6614
 
6615
/* Note that NAME was looked up while the current class was being
6616
   defined and that the result of that lookup was DECL.  */
6617
 
6618
void
6619
maybe_note_name_used_in_class (tree name, tree decl)
6620
{
6621
  splay_tree names_used;
6622
 
6623
  /* If we're not defining a class, there's nothing to do.  */
6624
  if (!(innermost_scope_kind() == sk_class
6625
        && TYPE_BEING_DEFINED (current_class_type)
6626
        && !LAMBDA_TYPE_P (current_class_type)))
6627
    return;
6628
 
6629
  /* If there's already a binding for this NAME, then we don't have
6630
     anything to worry about.  */
6631
  if (lookup_member (current_class_type, name,
6632
                     /*protect=*/0, /*want_type=*/false))
6633
    return;
6634
 
6635
  if (!current_class_stack[current_class_depth - 1].names_used)
6636
    current_class_stack[current_class_depth - 1].names_used
6637
      = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6638
  names_used = current_class_stack[current_class_depth - 1].names_used;
6639
 
6640
  splay_tree_insert (names_used,
6641
                     (splay_tree_key) name,
6642
                     (splay_tree_value) decl);
6643
}
6644
 
6645
/* Note that NAME was declared (as DECL) in the current class.  Check
6646
   to see that the declaration is valid.  */
6647
 
6648
void
6649
note_name_declared_in_class (tree name, tree decl)
6650
{
6651
  splay_tree names_used;
6652
  splay_tree_node n;
6653
 
6654
  /* Look to see if we ever used this name.  */
6655
  names_used
6656
    = current_class_stack[current_class_depth - 1].names_used;
6657
  if (!names_used)
6658
    return;
6659
 
6660
  n = splay_tree_lookup (names_used, (splay_tree_key) name);
6661
  if (n)
6662
    {
6663
      /* [basic.scope.class]
6664
 
6665
         A name N used in a class S shall refer to the same declaration
6666
         in its context and when re-evaluated in the completed scope of
6667
         S.  */
6668
      permerror (input_location, "declaration of %q#D", decl);
6669
      permerror (input_location, "changes meaning of %qD from %q+#D",
6670
               DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6671
    }
6672
}
6673
 
6674
/* Returns the VAR_DECL for the complete vtable associated with BINFO.
6675
   Secondary vtables are merged with primary vtables; this function
6676
   will return the VAR_DECL for the primary vtable.  */
6677
 
6678
tree
6679
get_vtbl_decl_for_binfo (tree binfo)
6680
{
6681
  tree decl;
6682
 
6683
  decl = BINFO_VTABLE (binfo);
6684
  if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6685
    {
6686
      gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6687
      decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6688
    }
6689
  if (decl)
6690
    gcc_assert (TREE_CODE (decl) == VAR_DECL);
6691
  return decl;
6692
}
6693
 
6694
 
6695
/* Returns the binfo for the primary base of BINFO.  If the resulting
6696
   BINFO is a virtual base, and it is inherited elsewhere in the
6697
   hierarchy, then the returned binfo might not be the primary base of
6698
   BINFO in the complete object.  Check BINFO_PRIMARY_P or
6699
   BINFO_LOST_PRIMARY_P to be sure.  */
6700
 
6701
static tree
6702
get_primary_binfo (tree binfo)
6703
{
6704
  tree primary_base;
6705
 
6706
  primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6707
  if (!primary_base)
6708
    return NULL_TREE;
6709
 
6710
  return copied_binfo (primary_base, binfo);
6711
}
6712
 
6713
/* If INDENTED_P is zero, indent to INDENT. Return nonzero.  */
6714
 
6715
static int
6716
maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6717
{
6718
  if (!indented_p)
6719
    fprintf (stream, "%*s", indent, "");
6720
  return 1;
6721
}
6722
 
6723
/* Dump the offsets of all the bases rooted at BINFO to STREAM.
6724
   INDENT should be zero when called from the top level; it is
6725
   incremented recursively.  IGO indicates the next expected BINFO in
6726
   inheritance graph ordering.  */
6727
 
6728
static tree
6729
dump_class_hierarchy_r (FILE *stream,
6730
                        int flags,
6731
                        tree binfo,
6732
                        tree igo,
6733
                        int indent)
6734
{
6735
  int indented = 0;
6736
  tree base_binfo;
6737
  int i;
6738
 
6739
  indented = maybe_indent_hierarchy (stream, indent, 0);
6740
  fprintf (stream, "%s (0x%lx) ",
6741
           type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6742
           (unsigned long) binfo);
6743
  if (binfo != igo)
6744
    {
6745
      fprintf (stream, "alternative-path\n");
6746
      return igo;
6747
    }
6748
  igo = TREE_CHAIN (binfo);
6749
 
6750
  fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6751
           tree_low_cst (BINFO_OFFSET (binfo), 0));
6752
  if (is_empty_class (BINFO_TYPE (binfo)))
6753
    fprintf (stream, " empty");
6754
  else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6755
    fprintf (stream, " nearly-empty");
6756
  if (BINFO_VIRTUAL_P (binfo))
6757
    fprintf (stream, " virtual");
6758
  fprintf (stream, "\n");
6759
 
6760
  indented = 0;
6761
  if (BINFO_PRIMARY_P (binfo))
6762
    {
6763
      indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6764
      fprintf (stream, " primary-for %s (0x%lx)",
6765
               type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6766
                               TFF_PLAIN_IDENTIFIER),
6767
               (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6768
    }
6769
  if (BINFO_LOST_PRIMARY_P (binfo))
6770
    {
6771
      indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6772
      fprintf (stream, " lost-primary");
6773
    }
6774
  if (indented)
6775
    fprintf (stream, "\n");
6776
 
6777
  if (!(flags & TDF_SLIM))
6778
    {
6779
      int indented = 0;
6780
 
6781
      if (BINFO_SUBVTT_INDEX (binfo))
6782
        {
6783
          indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6784
          fprintf (stream, " subvttidx=%s",
6785
                   expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6786
                                   TFF_PLAIN_IDENTIFIER));
6787
        }
6788
      if (BINFO_VPTR_INDEX (binfo))
6789
        {
6790
          indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6791
          fprintf (stream, " vptridx=%s",
6792
                   expr_as_string (BINFO_VPTR_INDEX (binfo),
6793
                                   TFF_PLAIN_IDENTIFIER));
6794
        }
6795
      if (BINFO_VPTR_FIELD (binfo))
6796
        {
6797
          indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6798
          fprintf (stream, " vbaseoffset=%s",
6799
                   expr_as_string (BINFO_VPTR_FIELD (binfo),
6800
                                   TFF_PLAIN_IDENTIFIER));
6801
        }
6802
      if (BINFO_VTABLE (binfo))
6803
        {
6804
          indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6805
          fprintf (stream, " vptr=%s",
6806
                   expr_as_string (BINFO_VTABLE (binfo),
6807
                                   TFF_PLAIN_IDENTIFIER));
6808
        }
6809
 
6810
      if (indented)
6811
        fprintf (stream, "\n");
6812
    }
6813
 
6814
  for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6815
    igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6816
 
6817
  return igo;
6818
}
6819
 
6820
/* Dump the BINFO hierarchy for T.  */
6821
 
6822
static void
6823
dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6824
{
6825
  fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6826
  fprintf (stream, "   size=%lu align=%lu\n",
6827
           (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6828
           (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6829
  fprintf (stream, "   base size=%lu base align=%lu\n",
6830
           (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6831
                           / BITS_PER_UNIT),
6832
           (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6833
                           / BITS_PER_UNIT));
6834
  dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6835
  fprintf (stream, "\n");
6836
}
6837
 
6838
/* Debug interface to hierarchy dumping.  */
6839
 
6840
void
6841
debug_class (tree t)
6842
{
6843
  dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6844
}
6845
 
6846
static void
6847
dump_class_hierarchy (tree t)
6848
{
6849
  int flags;
6850
  FILE *stream = dump_begin (TDI_class, &flags);
6851
 
6852
  if (stream)
6853
    {
6854
      dump_class_hierarchy_1 (stream, flags, t);
6855
      dump_end (TDI_class, stream);
6856
    }
6857
}
6858
 
6859
static void
6860
dump_array (FILE * stream, tree decl)
6861
{
6862
  tree value;
6863
  unsigned HOST_WIDE_INT ix;
6864
  HOST_WIDE_INT elt;
6865
  tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6866
 
6867
  elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6868
         / BITS_PER_UNIT);
6869
  fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6870
  fprintf (stream, " %s entries",
6871
           expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6872
                           TFF_PLAIN_IDENTIFIER));
6873
  fprintf (stream, "\n");
6874
 
6875
  FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6876
                              ix, value)
6877
    fprintf (stream, "%-4ld  %s\n", (long)(ix * elt),
6878
             expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6879
}
6880
 
6881
static void
6882
dump_vtable (tree t, tree binfo, tree vtable)
6883
{
6884
  int flags;
6885
  FILE *stream = dump_begin (TDI_class, &flags);
6886
 
6887
  if (!stream)
6888
    return;
6889
 
6890
  if (!(flags & TDF_SLIM))
6891
    {
6892
      int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6893
 
6894
      fprintf (stream, "%s for %s",
6895
               ctor_vtbl_p ? "Construction vtable" : "Vtable",
6896
               type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6897
      if (ctor_vtbl_p)
6898
        {
6899
          if (!BINFO_VIRTUAL_P (binfo))
6900
            fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6901
          fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6902
        }
6903
      fprintf (stream, "\n");
6904
      dump_array (stream, vtable);
6905
      fprintf (stream, "\n");
6906
    }
6907
 
6908
  dump_end (TDI_class, stream);
6909
}
6910
 
6911
static void
6912
dump_vtt (tree t, tree vtt)
6913
{
6914
  int flags;
6915
  FILE *stream = dump_begin (TDI_class, &flags);
6916
 
6917
  if (!stream)
6918
    return;
6919
 
6920
  if (!(flags & TDF_SLIM))
6921
    {
6922
      fprintf (stream, "VTT for %s\n",
6923
               type_as_string (t, TFF_PLAIN_IDENTIFIER));
6924
      dump_array (stream, vtt);
6925
      fprintf (stream, "\n");
6926
    }
6927
 
6928
  dump_end (TDI_class, stream);
6929
}
6930
 
6931
/* Dump a function or thunk and its thunkees.  */
6932
 
6933
static void
6934
dump_thunk (FILE *stream, int indent, tree thunk)
6935
{
6936
  static const char spaces[] = "        ";
6937
  tree name = DECL_NAME (thunk);
6938
  tree thunks;
6939
 
6940
  fprintf (stream, "%.*s%p %s %s", indent, spaces,
6941
           (void *)thunk,
6942
           !DECL_THUNK_P (thunk) ? "function"
6943
           : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6944
           name ? IDENTIFIER_POINTER (name) : "<unset>");
6945
  if (DECL_THUNK_P (thunk))
6946
    {
6947
      HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6948
      tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6949
 
6950
      fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6951
      if (!virtual_adjust)
6952
        /*NOP*/;
6953
      else if (DECL_THIS_THUNK_P (thunk))
6954
        fprintf (stream, " vcall="  HOST_WIDE_INT_PRINT_DEC,
6955
                 tree_low_cst (virtual_adjust, 0));
6956
      else
6957
        fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6958
                 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6959
                 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6960
      if (THUNK_ALIAS (thunk))
6961
        fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6962
    }
6963
  fprintf (stream, "\n");
6964
  for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6965
    dump_thunk (stream, indent + 2, thunks);
6966
}
6967
 
6968
/* Dump the thunks for FN.  */
6969
 
6970
void
6971
debug_thunks (tree fn)
6972
{
6973
  dump_thunk (stderr, 0, fn);
6974
}
6975
 
6976
/* Virtual function table initialization.  */
6977
 
6978
/* Create all the necessary vtables for T and its base classes.  */
6979
 
6980
static void
6981
finish_vtbls (tree t)
6982
{
6983
  tree list;
6984
  tree vbase;
6985
 
6986
  /* We lay out the primary and secondary vtables in one contiguous
6987
     vtable.  The primary vtable is first, followed by the non-virtual
6988
     secondary vtables in inheritance graph order.  */
6989
  list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6990
  accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6991
                         TYPE_BINFO (t), t, list);
6992
 
6993
  /* Then come the virtual bases, also in inheritance graph order.  */
6994
  for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6995
    {
6996
      if (!BINFO_VIRTUAL_P (vbase))
6997
        continue;
6998
      accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6999
    }
7000
 
7001
  if (BINFO_VTABLE (TYPE_BINFO (t)))
7002
    initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
7003
}
7004
 
7005
/* Initialize the vtable for BINFO with the INITS.  */
7006
 
7007
static void
7008
initialize_vtable (tree binfo, tree inits)
7009
{
7010
  tree decl;
7011
 
7012
  layout_vtable_decl (binfo, list_length (inits));
7013
  decl = get_vtbl_decl_for_binfo (binfo);
7014
  initialize_artificial_var (decl, inits);
7015
  dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7016
}
7017
 
7018
/* Build the VTT (virtual table table) for T.
7019
   A class requires a VTT if it has virtual bases.
7020
 
7021
   This holds
7022
   1 - primary virtual pointer for complete object T
7023
   2 - secondary VTTs for each direct non-virtual base of T which requires a
7024
       VTT
7025
   3 - secondary virtual pointers for each direct or indirect base of T which
7026
       has virtual bases or is reachable via a virtual path from T.
7027
   4 - secondary VTTs for each direct or indirect virtual base of T.
7028
 
7029
   Secondary VTTs look like complete object VTTs without part 4.  */
7030
 
7031
static void
7032
build_vtt (tree t)
7033
{
7034
  tree inits;
7035
  tree type;
7036
  tree vtt;
7037
  tree index;
7038
 
7039
  /* Build up the initializers for the VTT.  */
7040
  inits = NULL_TREE;
7041
  index = size_zero_node;
7042
  build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7043
 
7044
  /* If we didn't need a VTT, we're done.  */
7045
  if (!inits)
7046
    return;
7047
 
7048
  /* Figure out the type of the VTT.  */
7049
  type = build_index_type (size_int (list_length (inits) - 1));
7050
  type = build_cplus_array_type (const_ptr_type_node, type);
7051
 
7052
  /* Now, build the VTT object itself.  */
7053
  vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7054
  initialize_artificial_var (vtt, inits);
7055
  /* Add the VTT to the vtables list.  */
7056
  TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
7057
  TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7058
 
7059
  dump_vtt (t, vtt);
7060
}
7061
 
7062
/* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7063
   PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7064
   and CHAIN the vtable pointer for this binfo after construction is
7065
   complete.  VALUE can also be another BINFO, in which case we recurse.  */
7066
 
7067
static tree
7068
binfo_ctor_vtable (tree binfo)
7069
{
7070
  tree vt;
7071
 
7072
  while (1)
7073
    {
7074
      vt = BINFO_VTABLE (binfo);
7075
      if (TREE_CODE (vt) == TREE_LIST)
7076
        vt = TREE_VALUE (vt);
7077
      if (TREE_CODE (vt) == TREE_BINFO)
7078
        binfo = vt;
7079
      else
7080
        break;
7081
    }
7082
 
7083
  return vt;
7084
}
7085
 
7086
/* Data for secondary VTT initialization.  */
7087
typedef struct secondary_vptr_vtt_init_data_s
7088
{
7089
  /* Is this the primary VTT? */
7090
  bool top_level_p;
7091
 
7092
  /* Current index into the VTT.  */
7093
  tree index;
7094
 
7095
  /* TREE_LIST of initializers built up.  */
7096
  tree inits;
7097
 
7098
  /* The type being constructed by this secondary VTT.  */
7099
  tree type_being_constructed;
7100
} secondary_vptr_vtt_init_data;
7101
 
7102
/* Recursively build the VTT-initializer for BINFO (which is in the
7103
   hierarchy dominated by T).  INITS points to the end of the initializer
7104
   list to date.  INDEX is the VTT index where the next element will be
7105
   replaced.  Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7106
   not a subvtt for some base of T).  When that is so, we emit the sub-VTTs
7107
   for virtual bases of T. When it is not so, we build the constructor
7108
   vtables for the BINFO-in-T variant.  */
7109
 
7110
static tree *
7111
build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
7112
{
7113
  int i;
7114
  tree b;
7115
  tree init;
7116
  tree secondary_vptrs;
7117
  secondary_vptr_vtt_init_data data;
7118
  int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7119
 
7120
  /* We only need VTTs for subobjects with virtual bases.  */
7121
  if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7122
    return inits;
7123
 
7124
  /* We need to use a construction vtable if this is not the primary
7125
     VTT.  */
7126
  if (!top_level_p)
7127
    {
7128
      build_ctor_vtbl_group (binfo, t);
7129
 
7130
      /* Record the offset in the VTT where this sub-VTT can be found.  */
7131
      BINFO_SUBVTT_INDEX (binfo) = *index;
7132
    }
7133
 
7134
  /* Add the address of the primary vtable for the complete object.  */
7135
  init = binfo_ctor_vtable (binfo);
7136
  *inits = build_tree_list (NULL_TREE, init);
7137
  inits = &TREE_CHAIN (*inits);
7138
  if (top_level_p)
7139
    {
7140
      gcc_assert (!BINFO_VPTR_INDEX (binfo));
7141
      BINFO_VPTR_INDEX (binfo) = *index;
7142
    }
7143
  *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7144
 
7145
  /* Recursively add the secondary VTTs for non-virtual bases.  */
7146
  for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7147
    if (!BINFO_VIRTUAL_P (b))
7148
      inits = build_vtt_inits (b, t, inits, index);
7149
 
7150
  /* Add secondary virtual pointers for all subobjects of BINFO with
7151
     either virtual bases or reachable along a virtual path, except
7152
     subobjects that are non-virtual primary bases.  */
7153
  data.top_level_p = top_level_p;
7154
  data.index = *index;
7155
  data.inits = NULL;
7156
  data.type_being_constructed = BINFO_TYPE (binfo);
7157
 
7158
  dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7159
 
7160
  *index = data.index;
7161
 
7162
  /* The secondary vptrs come back in reverse order.  After we reverse
7163
     them, and add the INITS, the last init will be the first element
7164
     of the chain.  */
7165
  secondary_vptrs = data.inits;
7166
  if (secondary_vptrs)
7167
    {
7168
      *inits = nreverse (secondary_vptrs);
7169
      inits = &TREE_CHAIN (secondary_vptrs);
7170
      gcc_assert (*inits == NULL_TREE);
7171
    }
7172
 
7173
  if (top_level_p)
7174
    /* Add the secondary VTTs for virtual bases in inheritance graph
7175
       order.  */
7176
    for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7177
      {
7178
        if (!BINFO_VIRTUAL_P (b))
7179
          continue;
7180
 
7181
        inits = build_vtt_inits (b, t, inits, index);
7182
      }
7183
  else
7184
    /* Remove the ctor vtables we created.  */
7185
    dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7186
 
7187
  return inits;
7188
}
7189
 
7190
/* Called from build_vtt_inits via dfs_walk.  BINFO is the binfo for the base
7191
   in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure.  */
7192
 
7193
static tree
7194
dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7195
{
7196
  secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7197
 
7198
  /* We don't care about bases that don't have vtables.  */
7199
  if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7200
    return dfs_skip_bases;
7201
 
7202
  /* We're only interested in proper subobjects of the type being
7203
     constructed.  */
7204
  if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7205
    return NULL_TREE;
7206
 
7207
  /* We're only interested in bases with virtual bases or reachable
7208
     via a virtual path from the type being constructed.  */
7209
  if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7210
        || binfo_via_virtual (binfo, data->type_being_constructed)))
7211
    return dfs_skip_bases;
7212
 
7213
  /* We're not interested in non-virtual primary bases.  */
7214
  if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7215
    return NULL_TREE;
7216
 
7217
  /* Record the index where this secondary vptr can be found.  */
7218
  if (data->top_level_p)
7219
    {
7220
      gcc_assert (!BINFO_VPTR_INDEX (binfo));
7221
      BINFO_VPTR_INDEX (binfo) = data->index;
7222
 
7223
      if (BINFO_VIRTUAL_P (binfo))
7224
        {
7225
          /* It's a primary virtual base, and this is not a
7226
             construction vtable.  Find the base this is primary of in
7227
             the inheritance graph, and use that base's vtable
7228
             now.  */
7229
          while (BINFO_PRIMARY_P (binfo))
7230
            binfo = BINFO_INHERITANCE_CHAIN (binfo);
7231
        }
7232
    }
7233
 
7234
  /* Add the initializer for the secondary vptr itself.  */
7235
  data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
7236
 
7237
  /* Advance the vtt index.  */
7238
  data->index = size_binop (PLUS_EXPR, data->index,
7239
                            TYPE_SIZE_UNIT (ptr_type_node));
7240
 
7241
  return NULL_TREE;
7242
}
7243
 
7244
/* Called from build_vtt_inits via dfs_walk. After building
7245
   constructor vtables and generating the sub-vtt from them, we need
7246
   to restore the BINFO_VTABLES that were scribbled on.  DATA is the
7247
   binfo of the base whose sub vtt was generated.  */
7248
 
7249
static tree
7250
dfs_fixup_binfo_vtbls (tree binfo, void* data)
7251
{
7252
  tree vtable = BINFO_VTABLE (binfo);
7253
 
7254
  if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7255
    /* If this class has no vtable, none of its bases do.  */
7256
    return dfs_skip_bases;
7257
 
7258
  if (!vtable)
7259
    /* This might be a primary base, so have no vtable in this
7260
       hierarchy.  */
7261
    return NULL_TREE;
7262
 
7263
  /* If we scribbled the construction vtable vptr into BINFO, clear it
7264
     out now.  */
7265
  if (TREE_CODE (vtable) == TREE_LIST
7266
      && (TREE_PURPOSE (vtable) == (tree) data))
7267
    BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7268
 
7269
  return NULL_TREE;
7270
}
7271
 
7272
/* Build the construction vtable group for BINFO which is in the
7273
   hierarchy dominated by T.  */
7274
 
7275
static void
7276
build_ctor_vtbl_group (tree binfo, tree t)
7277
{
7278
  tree list;
7279
  tree type;
7280
  tree vtbl;
7281
  tree inits;
7282
  tree id;
7283
  tree vbase;
7284
 
7285
  /* See if we've already created this construction vtable group.  */
7286
  id = mangle_ctor_vtbl_for_type (t, binfo);
7287
  if (IDENTIFIER_GLOBAL_VALUE (id))
7288
    return;
7289
 
7290
  gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7291
  /* Build a version of VTBL (with the wrong type) for use in
7292
     constructing the addresses of secondary vtables in the
7293
     construction vtable group.  */
7294
  vtbl = build_vtable (t, id, ptr_type_node);
7295
  DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7296
  list = build_tree_list (vtbl, NULL_TREE);
7297
  accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7298
                         binfo, t, list);
7299
 
7300
  /* Add the vtables for each of our virtual bases using the vbase in T
7301
     binfo.  */
7302
  for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7303
       vbase;
7304
       vbase = TREE_CHAIN (vbase))
7305
    {
7306
      tree b;
7307
 
7308
      if (!BINFO_VIRTUAL_P (vbase))
7309
        continue;
7310
      b = copied_binfo (vbase, binfo);
7311
 
7312
      accumulate_vtbl_inits (b, vbase, binfo, t, list);
7313
    }
7314
  inits = TREE_VALUE (list);
7315
 
7316
  /* Figure out the type of the construction vtable.  */
7317
  type = build_index_type (size_int (list_length (inits) - 1));
7318
  type = build_cplus_array_type (vtable_entry_type, type);
7319
  layout_type (type);
7320
  TREE_TYPE (vtbl) = type;
7321
  DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7322
  layout_decl (vtbl, 0);
7323
 
7324
  /* Initialize the construction vtable.  */
7325
  CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7326
  initialize_artificial_var (vtbl, inits);
7327
  dump_vtable (t, binfo, vtbl);
7328
}
7329
 
7330
/* Add the vtbl initializers for BINFO (and its bases other than
7331
   non-virtual primaries) to the list of INITS.  BINFO is in the
7332
   hierarchy dominated by T.  RTTI_BINFO is the binfo within T of
7333
   the constructor the vtbl inits should be accumulated for. (If this
7334
   is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7335
   ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7336
   BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7337
   graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7338
   but are not necessarily the same in terms of layout.  */
7339
 
7340
static void
7341
accumulate_vtbl_inits (tree binfo,
7342
                       tree orig_binfo,
7343
                       tree rtti_binfo,
7344
                       tree t,
7345
                       tree inits)
7346
{
7347
  int i;
7348
  tree base_binfo;
7349
  int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7350
 
7351
  gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7352
 
7353
  /* If it doesn't have a vptr, we don't do anything.  */
7354
  if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7355
    return;
7356
 
7357
  /* If we're building a construction vtable, we're not interested in
7358
     subobjects that don't require construction vtables.  */
7359
  if (ctor_vtbl_p
7360
      && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7361
      && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7362
    return;
7363
 
7364
  /* Build the initializers for the BINFO-in-T vtable.  */
7365
  TREE_VALUE (inits)
7366
    = chainon (TREE_VALUE (inits),
7367
               dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7368
                                          rtti_binfo, t, inits));
7369
 
7370
  /* Walk the BINFO and its bases.  We walk in preorder so that as we
7371
     initialize each vtable we can figure out at what offset the
7372
     secondary vtable lies from the primary vtable.  We can't use
7373
     dfs_walk here because we need to iterate through bases of BINFO
7374
     and RTTI_BINFO simultaneously.  */
7375
  for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7376
    {
7377
      /* Skip virtual bases.  */
7378
      if (BINFO_VIRTUAL_P (base_binfo))
7379
        continue;
7380
      accumulate_vtbl_inits (base_binfo,
7381
                             BINFO_BASE_BINFO (orig_binfo, i),
7382
                             rtti_binfo, t,
7383
                             inits);
7384
    }
7385
}
7386
 
7387
/* Called from accumulate_vtbl_inits.  Returns the initializers for
7388
   the BINFO vtable.  */
7389
 
7390
static tree
7391
dfs_accumulate_vtbl_inits (tree binfo,
7392
                           tree orig_binfo,
7393
                           tree rtti_binfo,
7394
                           tree t,
7395
                           tree l)
7396
{
7397
  tree inits = NULL_TREE;
7398
  tree vtbl = NULL_TREE;
7399
  int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7400
 
7401
  if (ctor_vtbl_p
7402
      && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7403
    {
7404
      /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7405
         primary virtual base.  If it is not the same primary in
7406
         the hierarchy of T, we'll need to generate a ctor vtable
7407
         for it, to place at its location in T.  If it is the same
7408
         primary, we still need a VTT entry for the vtable, but it
7409
         should point to the ctor vtable for the base it is a
7410
         primary for within the sub-hierarchy of RTTI_BINFO.
7411
 
7412
         There are three possible cases:
7413
 
7414
         1) We are in the same place.
7415
         2) We are a primary base within a lost primary virtual base of
7416
         RTTI_BINFO.
7417
         3) We are primary to something not a base of RTTI_BINFO.  */
7418
 
7419
      tree b;
7420
      tree last = NULL_TREE;
7421
 
7422
      /* First, look through the bases we are primary to for RTTI_BINFO
7423
         or a virtual base.  */
7424
      b = binfo;
7425
      while (BINFO_PRIMARY_P (b))
7426
        {
7427
          b = BINFO_INHERITANCE_CHAIN (b);
7428
          last = b;
7429
          if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7430
            goto found;
7431
        }
7432
      /* If we run out of primary links, keep looking down our
7433
         inheritance chain; we might be an indirect primary.  */
7434
      for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7435
        if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7436
          break;
7437
    found:
7438
 
7439
      /* If we found RTTI_BINFO, this is case 1.  If we found a virtual
7440
         base B and it is a base of RTTI_BINFO, this is case 2.  In
7441
         either case, we share our vtable with LAST, i.e. the
7442
         derived-most base within B of which we are a primary.  */
7443
      if (b == rtti_binfo
7444
          || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7445
        /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7446
           set LAST's BINFO_VTABLE yet.  We'll extract the actual vptr in
7447
           binfo_ctor_vtable after everything's been set up.  */
7448
        vtbl = last;
7449
 
7450
      /* Otherwise, this is case 3 and we get our own.  */
7451
    }
7452
  else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7453
    return inits;
7454
 
7455
  if (!vtbl)
7456
    {
7457
      tree index;
7458
      int non_fn_entries;
7459
 
7460
      /* Compute the initializer for this vtable.  */
7461
      inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7462
                                      &non_fn_entries);
7463
 
7464
      /* Figure out the position to which the VPTR should point.  */
7465
      vtbl = TREE_PURPOSE (l);
7466
      vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7467
      index = size_binop (PLUS_EXPR,
7468
                          size_int (non_fn_entries),
7469
                          size_int (list_length (TREE_VALUE (l))));
7470
      index = size_binop (MULT_EXPR,
7471
                          TYPE_SIZE_UNIT (vtable_entry_type),
7472
                          index);
7473
      vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7474
    }
7475
 
7476
  if (ctor_vtbl_p)
7477
    /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7478
       So, we make a TREE_LIST.  Later, dfs_fixup_binfo_vtbls will
7479
       straighten this out.  */
7480
    BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7481
  else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7482
    inits = NULL_TREE;
7483
  else
7484
     /* For an ordinary vtable, set BINFO_VTABLE.  */
7485
    BINFO_VTABLE (binfo) = vtbl;
7486
 
7487
  return inits;
7488
}
7489
 
7490
static GTY(()) tree abort_fndecl_addr;
7491
 
7492
/* Construct the initializer for BINFO's virtual function table.  BINFO
7493
   is part of the hierarchy dominated by T.  If we're building a
7494
   construction vtable, the ORIG_BINFO is the binfo we should use to
7495
   find the actual function pointers to put in the vtable - but they
7496
   can be overridden on the path to most-derived in the graph that
7497
   ORIG_BINFO belongs.  Otherwise,
7498
   ORIG_BINFO should be the same as BINFO.  The RTTI_BINFO is the
7499
   BINFO that should be indicated by the RTTI information in the
7500
   vtable; it will be a base class of T, rather than T itself, if we
7501
   are building a construction vtable.
7502
 
7503
   The value returned is a TREE_LIST suitable for wrapping in a
7504
   CONSTRUCTOR to use as the DECL_INITIAL for a vtable.  If
7505
   NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7506
   number of non-function entries in the vtable.
7507
 
7508
   It might seem that this function should never be called with a
7509
   BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7510
   base is always subsumed by a derived class vtable.  However, when
7511
   we are building construction vtables, we do build vtables for
7512
   primary bases; we need these while the primary base is being
7513
   constructed.  */
7514
 
7515
static tree
7516
build_vtbl_initializer (tree binfo,
7517
                        tree orig_binfo,
7518
                        tree t,
7519
                        tree rtti_binfo,
7520
                        int* non_fn_entries_p)
7521
{
7522
  tree v, b;
7523
  tree vfun_inits;
7524
  vtbl_init_data vid;
7525
  unsigned ix;
7526
  tree vbinfo;
7527
  VEC(tree,gc) *vbases;
7528
 
7529
  /* Initialize VID.  */
7530
  memset (&vid, 0, sizeof (vid));
7531
  vid.binfo = binfo;
7532
  vid.derived = t;
7533
  vid.rtti_binfo = rtti_binfo;
7534
  vid.last_init = &vid.inits;
7535
  vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7536
  vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7537
  vid.generate_vcall_entries = true;
7538
  /* The first vbase or vcall offset is at index -3 in the vtable.  */
7539
  vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7540
 
7541
  /* Add entries to the vtable for RTTI.  */
7542
  build_rtti_vtbl_entries (binfo, &vid);
7543
 
7544
  /* Create an array for keeping track of the functions we've
7545
     processed.  When we see multiple functions with the same
7546
     signature, we share the vcall offsets.  */
7547
  vid.fns = VEC_alloc (tree, gc, 32);
7548
  /* Add the vcall and vbase offset entries.  */
7549
  build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7550
 
7551
  /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7552
     build_vbase_offset_vtbl_entries.  */
7553
  for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7554
       VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7555
    BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7556
 
7557
  /* If the target requires padding between data entries, add that now.  */
7558
  if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7559
    {
7560
      tree cur, *prev;
7561
 
7562
      for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7563
        {
7564
          tree add = cur;
7565
          int i;
7566
 
7567
          for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7568
            add = tree_cons (NULL_TREE,
7569
                             build1 (NOP_EXPR, vtable_entry_type,
7570
                                     null_pointer_node),
7571
                             add);
7572
          *prev = add;
7573
        }
7574
    }
7575
 
7576
  if (non_fn_entries_p)
7577
    *non_fn_entries_p = list_length (vid.inits);
7578
 
7579
  /* Go through all the ordinary virtual functions, building up
7580
     initializers.  */
7581
  vfun_inits = NULL_TREE;
7582
  for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7583
    {
7584
      tree delta;
7585
      tree vcall_index;
7586
      tree fn, fn_original;
7587
      tree init = NULL_TREE;
7588
 
7589
      fn = BV_FN (v);
7590
      fn_original = fn;
7591
      if (DECL_THUNK_P (fn))
7592
        {
7593
          if (!DECL_NAME (fn))
7594
            finish_thunk (fn);
7595
          if (THUNK_ALIAS (fn))
7596
            {
7597
              fn = THUNK_ALIAS (fn);
7598
              BV_FN (v) = fn;
7599
            }
7600
          fn_original = THUNK_TARGET (fn);
7601
        }
7602
 
7603
      /* If the only definition of this function signature along our
7604
         primary base chain is from a lost primary, this vtable slot will
7605
         never be used, so just zero it out.  This is important to avoid
7606
         requiring extra thunks which cannot be generated with the function.
7607
 
7608
         We first check this in update_vtable_entry_for_fn, so we handle
7609
         restored primary bases properly; we also need to do it here so we
7610
         zero out unused slots in ctor vtables, rather than filling them
7611
         with erroneous values (though harmless, apart from relocation
7612
         costs).  */
7613
      for (b = binfo; ; b = get_primary_binfo (b))
7614
        {
7615
          /* We found a defn before a lost primary; go ahead as normal.  */
7616
          if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7617
            break;
7618
 
7619
          /* The nearest definition is from a lost primary; clear the
7620
             slot.  */
7621
          if (BINFO_LOST_PRIMARY_P (b))
7622
            {
7623
              init = size_zero_node;
7624
              break;
7625
            }
7626
        }
7627
 
7628
      if (! init)
7629
        {
7630
          /* Pull the offset for `this', and the function to call, out of
7631
             the list.  */
7632
          delta = BV_DELTA (v);
7633
          vcall_index = BV_VCALL_INDEX (v);
7634
 
7635
          gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7636
          gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7637
 
7638
          /* You can't call an abstract virtual function; it's abstract.
7639
             So, we replace these functions with __pure_virtual.  */
7640
          if (DECL_PURE_VIRTUAL_P (fn_original))
7641
            {
7642
              fn = abort_fndecl;
7643
              if (abort_fndecl_addr == NULL)
7644
                abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7645
              init = abort_fndecl_addr;
7646
            }
7647
          else
7648
            {
7649
              if (!integer_zerop (delta) || vcall_index)
7650
                {
7651
                  fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7652
                  if (!DECL_NAME (fn))
7653
                    finish_thunk (fn);
7654
                }
7655
              /* Take the address of the function, considering it to be of an
7656
                 appropriate generic type.  */
7657
              init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7658
            }
7659
        }
7660
 
7661
      /* And add it to the chain of initializers.  */
7662
      if (TARGET_VTABLE_USES_DESCRIPTORS)
7663
        {
7664
          int i;
7665
          if (init == size_zero_node)
7666
            for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7667
              vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7668
          else
7669
            for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7670
              {
7671
                tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7672
                                     TREE_OPERAND (init, 0),
7673
                                     build_int_cst (NULL_TREE, i));
7674
                TREE_CONSTANT (fdesc) = 1;
7675
 
7676
                vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7677
              }
7678
        }
7679
      else
7680
        vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7681
    }
7682
 
7683
  /* The initializers for virtual functions were built up in reverse
7684
     order; straighten them out now.  */
7685
  vfun_inits = nreverse (vfun_inits);
7686
 
7687
  /* The negative offset initializers are also in reverse order.  */
7688
  vid.inits = nreverse (vid.inits);
7689
 
7690
  /* Chain the two together.  */
7691
  return chainon (vid.inits, vfun_inits);
7692
}
7693
 
7694
/* Adds to vid->inits the initializers for the vbase and vcall
7695
   offsets in BINFO, which is in the hierarchy dominated by T.  */
7696
 
7697
static void
7698
build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7699
{
7700
  tree b;
7701
 
7702
  /* If this is a derived class, we must first create entries
7703
     corresponding to the primary base class.  */
7704
  b = get_primary_binfo (binfo);
7705
  if (b)
7706
    build_vcall_and_vbase_vtbl_entries (b, vid);
7707
 
7708
  /* Add the vbase entries for this base.  */
7709
  build_vbase_offset_vtbl_entries (binfo, vid);
7710
  /* Add the vcall entries for this base.  */
7711
  build_vcall_offset_vtbl_entries (binfo, vid);
7712
}
7713
 
7714
/* Returns the initializers for the vbase offset entries in the vtable
7715
   for BINFO (which is part of the class hierarchy dominated by T), in
7716
   reverse order.  VBASE_OFFSET_INDEX gives the vtable index
7717
   where the next vbase offset will go.  */
7718
 
7719
static void
7720
build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7721
{
7722
  tree vbase;
7723
  tree t;
7724
  tree non_primary_binfo;
7725
 
7726
  /* If there are no virtual baseclasses, then there is nothing to
7727
     do.  */
7728
  if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7729
    return;
7730
 
7731
  t = vid->derived;
7732
 
7733
  /* We might be a primary base class.  Go up the inheritance hierarchy
7734
     until we find the most derived class of which we are a primary base:
7735
     it is the offset of that which we need to use.  */
7736
  non_primary_binfo = binfo;
7737
  while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7738
    {
7739
      tree b;
7740
 
7741
      /* If we have reached a virtual base, then it must be a primary
7742
         base (possibly multi-level) of vid->binfo, or we wouldn't
7743
         have called build_vcall_and_vbase_vtbl_entries for it.  But it
7744
         might be a lost primary, so just skip down to vid->binfo.  */
7745
      if (BINFO_VIRTUAL_P (non_primary_binfo))
7746
        {
7747
          non_primary_binfo = vid->binfo;
7748
          break;
7749
        }
7750
 
7751
      b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7752
      if (get_primary_binfo (b) != non_primary_binfo)
7753
        break;
7754
      non_primary_binfo = b;
7755
    }
7756
 
7757
  /* Go through the virtual bases, adding the offsets.  */
7758
  for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7759
       vbase;
7760
       vbase = TREE_CHAIN (vbase))
7761
    {
7762
      tree b;
7763
      tree delta;
7764
 
7765
      if (!BINFO_VIRTUAL_P (vbase))
7766
        continue;
7767
 
7768
      /* Find the instance of this virtual base in the complete
7769
         object.  */
7770
      b = copied_binfo (vbase, binfo);
7771
 
7772
      /* If we've already got an offset for this virtual base, we
7773
         don't need another one.  */
7774
      if (BINFO_VTABLE_PATH_MARKED (b))
7775
        continue;
7776
      BINFO_VTABLE_PATH_MARKED (b) = 1;
7777
 
7778
      /* Figure out where we can find this vbase offset.  */
7779
      delta = size_binop (MULT_EXPR,
7780
                          vid->index,
7781
                          convert (ssizetype,
7782
                                   TYPE_SIZE_UNIT (vtable_entry_type)));
7783
      if (vid->primary_vtbl_p)
7784
        BINFO_VPTR_FIELD (b) = delta;
7785
 
7786
      if (binfo != TYPE_BINFO (t))
7787
        /* The vbase offset had better be the same.  */
7788
        gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7789
 
7790
      /* The next vbase will come at a more negative offset.  */
7791
      vid->index = size_binop (MINUS_EXPR, vid->index,
7792
                               ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7793
 
7794
      /* The initializer is the delta from BINFO to this virtual base.
7795
         The vbase offsets go in reverse inheritance-graph order, and
7796
         we are walking in inheritance graph order so these end up in
7797
         the right order.  */
7798
      delta = size_diffop_loc (input_location,
7799
                           BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7800
 
7801
      *vid->last_init
7802
        = build_tree_list (NULL_TREE,
7803
                           fold_build1_loc (input_location, NOP_EXPR,
7804
                                        vtable_entry_type,
7805
                                        delta));
7806
      vid->last_init = &TREE_CHAIN (*vid->last_init);
7807
    }
7808
}
7809
 
7810
/* Adds the initializers for the vcall offset entries in the vtable
7811
   for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7812
   to VID->INITS.  */
7813
 
7814
static void
7815
build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7816
{
7817
  /* We only need these entries if this base is a virtual base.  We
7818
     compute the indices -- but do not add to the vtable -- when
7819
     building the main vtable for a class.  */
7820
  if (binfo == TYPE_BINFO (vid->derived)
7821
      || (BINFO_VIRTUAL_P (binfo)
7822
          /* If BINFO is RTTI_BINFO, then (since BINFO does not
7823
             correspond to VID->DERIVED), we are building a primary
7824
             construction virtual table.  Since this is a primary
7825
             virtual table, we do not need the vcall offsets for
7826
             BINFO.  */
7827
          && binfo != vid->rtti_binfo))
7828
    {
7829
      /* We need a vcall offset for each of the virtual functions in this
7830
         vtable.  For example:
7831
 
7832
           class A { virtual void f (); };
7833
           class B1 : virtual public A { virtual void f (); };
7834
           class B2 : virtual public A { virtual void f (); };
7835
           class C: public B1, public B2 { virtual void f (); };
7836
 
7837
         A C object has a primary base of B1, which has a primary base of A.  A
7838
         C also has a secondary base of B2, which no longer has a primary base
7839
         of A.  So the B2-in-C construction vtable needs a secondary vtable for
7840
         A, which will adjust the A* to a B2* to call f.  We have no way of
7841
         knowing what (or even whether) this offset will be when we define B2,
7842
         so we store this "vcall offset" in the A sub-vtable and look it up in
7843
         a "virtual thunk" for B2::f.
7844
 
7845
         We need entries for all the functions in our primary vtable and
7846
         in our non-virtual bases' secondary vtables.  */
7847
      vid->vbase = binfo;
7848
      /* If we are just computing the vcall indices -- but do not need
7849
         the actual entries -- not that.  */
7850
      if (!BINFO_VIRTUAL_P (binfo))
7851
        vid->generate_vcall_entries = false;
7852
      /* Now, walk through the non-virtual bases, adding vcall offsets.  */
7853
      add_vcall_offset_vtbl_entries_r (binfo, vid);
7854
    }
7855
}
7856
 
7857
/* Build vcall offsets, starting with those for BINFO.  */
7858
 
7859
static void
7860
add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7861
{
7862
  int i;
7863
  tree primary_binfo;
7864
  tree base_binfo;
7865
 
7866
  /* Don't walk into virtual bases -- except, of course, for the
7867
     virtual base for which we are building vcall offsets.  Any
7868
     primary virtual base will have already had its offsets generated
7869
     through the recursion in build_vcall_and_vbase_vtbl_entries.  */
7870
  if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7871
    return;
7872
 
7873
  /* If BINFO has a primary base, process it first.  */
7874
  primary_binfo = get_primary_binfo (binfo);
7875
  if (primary_binfo)
7876
    add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7877
 
7878
  /* Add BINFO itself to the list.  */
7879
  add_vcall_offset_vtbl_entries_1 (binfo, vid);
7880
 
7881
  /* Scan the non-primary bases of BINFO.  */
7882
  for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7883
    if (base_binfo != primary_binfo)
7884
      add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7885
}
7886
 
7887
/* Called from build_vcall_offset_vtbl_entries_r.  */
7888
 
7889
static void
7890
add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7891
{
7892
  /* Make entries for the rest of the virtuals.  */
7893
  if (abi_version_at_least (2))
7894
    {
7895
      tree orig_fn;
7896
 
7897
      /* The ABI requires that the methods be processed in declaration
7898
         order.  G++ 3.2 used the order in the vtable.  */
7899
      for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7900
           orig_fn;
7901
           orig_fn = TREE_CHAIN (orig_fn))
7902
        if (DECL_VINDEX (orig_fn))
7903
          add_vcall_offset (orig_fn, binfo, vid);
7904
    }
7905
  else
7906
    {
7907
      tree derived_virtuals;
7908
      tree base_virtuals;
7909
      tree orig_virtuals;
7910
      /* If BINFO is a primary base, the most derived class which has
7911
         BINFO as a primary base; otherwise, just BINFO.  */
7912
      tree non_primary_binfo;
7913
 
7914
      /* We might be a primary base class.  Go up the inheritance hierarchy
7915
         until we find the most derived class of which we are a primary base:
7916
         it is the BINFO_VIRTUALS there that we need to consider.  */
7917
      non_primary_binfo = binfo;
7918
      while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7919
        {
7920
          tree b;
7921
 
7922
          /* If we have reached a virtual base, then it must be vid->vbase,
7923
             because we ignore other virtual bases in
7924
             add_vcall_offset_vtbl_entries_r.  In turn, it must be a primary
7925
             base (possibly multi-level) of vid->binfo, or we wouldn't
7926
             have called build_vcall_and_vbase_vtbl_entries for it.  But it
7927
             might be a lost primary, so just skip down to vid->binfo.  */
7928
          if (BINFO_VIRTUAL_P (non_primary_binfo))
7929
            {
7930
              gcc_assert (non_primary_binfo == vid->vbase);
7931
              non_primary_binfo = vid->binfo;
7932
              break;
7933
            }
7934
 
7935
          b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7936
          if (get_primary_binfo (b) != non_primary_binfo)
7937
            break;
7938
          non_primary_binfo = b;
7939
        }
7940
 
7941
      if (vid->ctor_vtbl_p)
7942
        /* For a ctor vtable we need the equivalent binfo within the hierarchy
7943
           where rtti_binfo is the most derived type.  */
7944
        non_primary_binfo
7945
          = original_binfo (non_primary_binfo, vid->rtti_binfo);
7946
 
7947
      for (base_virtuals = BINFO_VIRTUALS (binfo),
7948
             derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7949
             orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7950
           base_virtuals;
7951
           base_virtuals = TREE_CHAIN (base_virtuals),
7952
             derived_virtuals = TREE_CHAIN (derived_virtuals),
7953
             orig_virtuals = TREE_CHAIN (orig_virtuals))
7954
        {
7955
          tree orig_fn;
7956
 
7957
          /* Find the declaration that originally caused this function to
7958
             be present in BINFO_TYPE (binfo).  */
7959
          orig_fn = BV_FN (orig_virtuals);
7960
 
7961
          /* When processing BINFO, we only want to generate vcall slots for
7962
             function slots introduced in BINFO.  So don't try to generate
7963
             one if the function isn't even defined in BINFO.  */
7964
          if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7965
            continue;
7966
 
7967
          add_vcall_offset (orig_fn, binfo, vid);
7968
        }
7969
    }
7970
}
7971
 
7972
/* Add a vcall offset entry for ORIG_FN to the vtable.  */
7973
 
7974
static void
7975
add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7976
{
7977
  size_t i;
7978
  tree vcall_offset;
7979
  tree derived_entry;
7980
 
7981
  /* If there is already an entry for a function with the same
7982
     signature as FN, then we do not need a second vcall offset.
7983
     Check the list of functions already present in the derived
7984
     class vtable.  */
7985
  for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7986
    {
7987
      if (same_signature_p (derived_entry, orig_fn)
7988
          /* We only use one vcall offset for virtual destructors,
7989
             even though there are two virtual table entries.  */
7990
          || (DECL_DESTRUCTOR_P (derived_entry)
7991
              && DECL_DESTRUCTOR_P (orig_fn)))
7992
        return;
7993
    }
7994
 
7995
  /* If we are building these vcall offsets as part of building
7996
     the vtable for the most derived class, remember the vcall
7997
     offset.  */
7998
  if (vid->binfo == TYPE_BINFO (vid->derived))
7999
    {
8000
      tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8001
                                       CLASSTYPE_VCALL_INDICES (vid->derived),
8002
                                       NULL);
8003
      elt->purpose = orig_fn;
8004
      elt->value = vid->index;
8005
    }
8006
 
8007
  /* The next vcall offset will be found at a more negative
8008
     offset.  */
8009
  vid->index = size_binop (MINUS_EXPR, vid->index,
8010
                           ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8011
 
8012
  /* Keep track of this function.  */
8013
  VEC_safe_push (tree, gc, vid->fns, orig_fn);
8014
 
8015
  if (vid->generate_vcall_entries)
8016
    {
8017
      tree base;
8018
      tree fn;
8019
 
8020
      /* Find the overriding function.  */
8021
      fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8022
      if (fn == error_mark_node)
8023
        vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
8024
                               integer_zero_node);
8025
      else
8026
        {
8027
          base = TREE_VALUE (fn);
8028
 
8029
          /* The vbase we're working on is a primary base of
8030
             vid->binfo.  But it might be a lost primary, so its
8031
             BINFO_OFFSET might be wrong, so we just use the
8032
             BINFO_OFFSET from vid->binfo.  */
8033
          vcall_offset = size_diffop_loc (input_location,
8034
                                      BINFO_OFFSET (base),
8035
                                      BINFO_OFFSET (vid->binfo));
8036
          vcall_offset = fold_build1_loc (input_location,
8037
                                      NOP_EXPR, vtable_entry_type,
8038
                                      vcall_offset);
8039
        }
8040
      /* Add the initializer to the vtable.  */
8041
      *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
8042
      vid->last_init = &TREE_CHAIN (*vid->last_init);
8043
    }
8044
}
8045
 
8046
/* Return vtbl initializers for the RTTI entries corresponding to the
8047
   BINFO's vtable.  The RTTI entries should indicate the object given
8048
   by VID->rtti_binfo.  */
8049
 
8050
static void
8051
build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8052
{
8053
  tree b;
8054
  tree t;
8055
  tree offset;
8056
  tree decl;
8057
  tree init;
8058
 
8059
  t = BINFO_TYPE (vid->rtti_binfo);
8060
 
8061
  /* To find the complete object, we will first convert to our most
8062
     primary base, and then add the offset in the vtbl to that value.  */
8063
  b = binfo;
8064
  while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8065
         && !BINFO_LOST_PRIMARY_P (b))
8066
    {
8067
      tree primary_base;
8068
 
8069
      primary_base = get_primary_binfo (b);
8070
      gcc_assert (BINFO_PRIMARY_P (primary_base)
8071
                  && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8072
      b = primary_base;
8073
    }
8074
  offset = size_diffop_loc (input_location,
8075
                        BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8076
 
8077
  /* The second entry is the address of the typeinfo object.  */
8078
  if (flag_rtti)
8079
    decl = build_address (get_tinfo_decl (t));
8080
  else
8081
    decl = integer_zero_node;
8082
 
8083
  /* Convert the declaration to a type that can be stored in the
8084
     vtable.  */
8085
  init = build_nop (vfunc_ptr_type_node, decl);
8086
  *vid->last_init = build_tree_list (NULL_TREE, init);
8087
  vid->last_init = &TREE_CHAIN (*vid->last_init);
8088
 
8089
  /* Add the offset-to-top entry.  It comes earlier in the vtable than
8090
     the typeinfo entry.  Convert the offset to look like a
8091
     function pointer, so that we can put it in the vtable.  */
8092
  init = build_nop (vfunc_ptr_type_node, offset);
8093
  *vid->last_init = build_tree_list (NULL_TREE, init);
8094
  vid->last_init = &TREE_CHAIN (*vid->last_init);
8095
}
8096
 
8097
/* Fold a OBJ_TYPE_REF expression to the address of a function.
8098
   KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF).  */
8099
 
8100
tree
8101
cp_fold_obj_type_ref (tree ref, tree known_type)
8102
{
8103
  HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
8104
  HOST_WIDE_INT i = 0;
8105
  tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
8106
  tree fndecl;
8107
 
8108
  while (i != index)
8109
    {
8110
      i += (TARGET_VTABLE_USES_DESCRIPTORS
8111
            ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
8112
      v = TREE_CHAIN (v);
8113
    }
8114
 
8115
  fndecl = BV_FN (v);
8116
 
8117
#ifdef ENABLE_CHECKING
8118
  gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
8119
                                  DECL_VINDEX (fndecl)));
8120
#endif
8121
 
8122
  cgraph_node (fndecl)->local.vtable_method = true;
8123
 
8124
  return build_address (fndecl);
8125
}
8126
 
8127
#include "gt-cp-class.h"

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