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/* Separate lexical analyzer for GNU C++.

   Copyright (C) 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,

   1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.

   Hacked by Michael Tiemann (tiemann@cygnus.com)

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify

it under the terms of the GNU General Public License as published by

the Free Software Foundation; either version 2, or (at your option)

any later version.

GCC is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with GCC; see the file COPYING.  If not, write to

the Free Software Foundation, 51 Franklin Street, Fifth Floor,

Boston, MA 02110-1301, USA.  */

/* This file is the lexical analyzer for GNU C++.  */

#include "config.h"

#include "system.h"

#include "coretypes.h"

#include "tm.h"

#include "input.h"

#include "tree.h"

#include "cp-tree.h"

#include "cpplib.h"

#include "flags.h"

#include "c-pragma.h"

#include "toplev.h"

#include "output.h"

#include "tm_p.h"

#include "timevar.h"

static int interface_strcmp (const char *);

static void init_cp_pragma (void);

static tree parse_strconst_pragma (const char *, int);

static void handle_pragma_vtable (cpp_reader *);

static void handle_pragma_unit (cpp_reader *);

static void handle_pragma_interface (cpp_reader *);

static void handle_pragma_implementation (cpp_reader *);

static void handle_pragma_java_exceptions (cpp_reader *);

static void init_operators (void);

static void copy_lang_type (tree);

/* A constraint that can be tested at compile time.  */

#define CONSTRAINT(name, expr) extern int constraint_##name [(expr) ? 1 : -1]

/* Functions and data structures for #pragma interface.

   `#pragma implementation' means that the main file being compiled

   is considered to implement (provide) the classes that appear in

   its main body.  I.e., if this is file "foo.cc", and class `bar'

   is defined in "foo.cc", then we say that "foo.cc implements bar".

   All main input files "implement" themselves automagically.

   `#pragma interface' means that unless this file (of the form "foo.h"

   is not presently being included by file "foo.cc", the

   CLASSTYPE_INTERFACE_ONLY bit gets set.  The effect is that none

   of the vtables nor any of the inline functions defined in foo.h

   will ever be output.

   There are cases when we want to link files such as "defs.h" and

   "main.cc".  In this case, we give "defs.h" a `#pragma interface',

   and "main.cc" has `#pragma implementation "defs.h"'.  */

struct impl_files

{

  const char *filename;

  struct impl_files *next;

};

static struct impl_files *impl_file_chain;

void

cxx_finish (void)

{

  c_common_finish ();

}

/* A mapping from tree codes to operator name information.  */

operator_name_info_t operator_name_info[(int) LAST_CPLUS_TREE_CODE];

/* Similar, but for assignment operators.  */

operator_name_info_t assignment_operator_name_info[(int) LAST_CPLUS_TREE_CODE];

/* Initialize data structures that keep track of operator names.  */

#define DEF_OPERATOR(NAME, C, M, AR, AP) \

 CONSTRAINT (C, sizeof "operator " + sizeof NAME <= 256);

#include "operators.def"

#undef DEF_OPERATOR

static void

init_operators (void)

{

  tree identifier;

  char buffer[256];

  struct operator_name_info_t *oni;

#define DEF_OPERATOR(NAME, CODE, MANGLING, ARITY, ASSN_P)                   \

  sprintf (buffer, ISALPHA (NAME[0]) ? "operator %s" : "operator%s", NAME); \

  identifier = get_identifier (buffer);                                     \

  IDENTIFIER_OPNAME_P (identifier) = 1;                                     \

                                                                            \

  oni = (ASSN_P                                                             \

         ? &assignment_operator_name_info[(int) CODE]                       \

         : &operator_name_info[(int) CODE]);                                \

  oni->identifier = identifier;                                             \

  oni->name = NAME;                                                         \

  oni->mangled_name = MANGLING;                                             \

  oni->arity = ARITY;

#include "operators.def"

#undef DEF_OPERATOR

  operator_name_info[(int) ERROR_MARK].identifier

    = get_identifier ("<invalid operator>");

  /* Handle some special cases.  These operators are not defined in

     the language, but can be produced internally.  We may need them

     for error-reporting.  (Eventually, we should ensure that this

     does not happen.  Error messages involving these operators will

     be confusing to users.)  */

  operator_name_info [(int) INIT_EXPR].name

    = operator_name_info [(int) MODIFY_EXPR].name;

  operator_name_info [(int) EXACT_DIV_EXPR].name = "(ceiling /)";

  operator_name_info [(int) CEIL_DIV_EXPR].name = "(ceiling /)";

  operator_name_info [(int) FLOOR_DIV_EXPR].name = "(floor /)";

  operator_name_info [(int) ROUND_DIV_EXPR].name = "(round /)";

  operator_name_info [(int) CEIL_MOD_EXPR].name = "(ceiling %)";

  operator_name_info [(int) FLOOR_MOD_EXPR].name = "(floor %)";

  operator_name_info [(int) ROUND_MOD_EXPR].name = "(round %)";

  operator_name_info [(int) ABS_EXPR].name = "abs";

  operator_name_info [(int) TRUTH_AND_EXPR].name = "strict &&";

  operator_name_info [(int) TRUTH_OR_EXPR].name = "strict ||";

  operator_name_info [(int) RANGE_EXPR].name = "...";

  operator_name_info [(int) UNARY_PLUS_EXPR].name = "+";

  assignment_operator_name_info [(int) EXACT_DIV_EXPR].name

    = "(exact /=)";

  assignment_operator_name_info [(int) CEIL_DIV_EXPR].name

    = "(ceiling /=)";

  assignment_operator_name_info [(int) FLOOR_DIV_EXPR].name

    = "(floor /=)";

  assignment_operator_name_info [(int) ROUND_DIV_EXPR].name

    = "(round /=)";

  assignment_operator_name_info [(int) CEIL_MOD_EXPR].name

    = "(ceiling %=)";

  assignment_operator_name_info [(int) FLOOR_MOD_EXPR].name

    = "(floor %=)";

  assignment_operator_name_info [(int) ROUND_MOD_EXPR].name

    = "(round %=)";

}

/* The reserved keyword table.  */

struct resword

{

  const char *const word;

  ENUM_BITFIELD(rid) const rid : 16;

  const unsigned int disable   : 16;

};

/* Disable mask.  Keywords are disabled if (reswords[i].disable & mask) is

   _true_.  */

#define D_EXT           0x01    /* GCC extension */

#define D_ASM           0x02    /* in C99, but has a switch to turn it off */

#define D_OBJC          0x04    /* Objective C++ only */

CONSTRAINT(ridbits_fit, RID_LAST_MODIFIER < sizeof(unsigned long) * CHAR_BIT);

static const struct resword reswords[] =

{

  { "_Complex",         RID_COMPLEX,    0 },

  { "__FUNCTION__",     RID_FUNCTION_NAME, 0 },

  { "__PRETTY_FUNCTION__", RID_PRETTY_FUNCTION_NAME, 0 },

  { "__alignof",        RID_ALIGNOF,    0 },

  { "__alignof__",      RID_ALIGNOF,    0 },

  { "__asm",            RID_ASM,        0 },

  { "__asm__",          RID_ASM,        0 },

  { "__attribute",      RID_ATTRIBUTE,  0 },

  { "__attribute__",    RID_ATTRIBUTE,  0 },

  { "__builtin_offsetof", RID_OFFSETOF, 0 },

  { "__builtin_va_arg", RID_VA_ARG,     0 },

  { "__complex",        RID_COMPLEX,    0 },

  { "__complex__",      RID_COMPLEX,    0 },

  { "__const",          RID_CONST,      0 },

  { "__const__",        RID_CONST,      0 },

  { "__extension__",    RID_EXTENSION,  0 },

  { "__func__",         RID_C99_FUNCTION_NAME,  0 },

  { "__imag",           RID_IMAGPART,   0 },

  { "__imag__",         RID_IMAGPART,   0 },

  { "__inline",         RID_INLINE,     0 },

  { "__inline__",       RID_INLINE,     0 },

  { "__label__",        RID_LABEL,      0 },

  { "__null",           RID_NULL,       0 },

  { "__real",           RID_REALPART,   0 },

  { "__real__",         RID_REALPART,   0 },

  { "__restrict",       RID_RESTRICT,   0 },

  { "__restrict__",     RID_RESTRICT,   0 },

  { "__signed",         RID_SIGNED,     0 },

  { "__signed__",       RID_SIGNED,     0 },

  { "__thread",         RID_THREAD,     0 },

  { "__typeof",         RID_TYPEOF,     0 },

  { "__typeof__",       RID_TYPEOF,     0 },

  { "__volatile",       RID_VOLATILE,   0 },

  { "__volatile__",     RID_VOLATILE,   0 },

  { "asm",              RID_ASM,        D_ASM },

  { "auto",             RID_AUTO,       0 },

  { "bool",             RID_BOOL,       0 },

  { "break",            RID_BREAK,      0 },

  { "case",             RID_CASE,       0 },

  { "catch",            RID_CATCH,      0 },

  { "char",             RID_CHAR,       0 },

  { "class",            RID_CLASS,      0 },

  { "const",            RID_CONST,      0 },

  { "const_cast",       RID_CONSTCAST,  0 },

  { "continue",         RID_CONTINUE,   0 },

  { "default",          RID_DEFAULT,    0 },

  { "delete",           RID_DELETE,     0 },

  { "do",               RID_DO,         0 },

  { "double",           RID_DOUBLE,     0 },

  { "dynamic_cast",     RID_DYNCAST,    0 },

  { "else",             RID_ELSE,       0 },

  { "enum",             RID_ENUM,       0 },

  { "explicit",         RID_EXPLICIT,   0 },

  { "export",           RID_EXPORT,     0 },

  { "extern",           RID_EXTERN,     0 },

  { "false",            RID_FALSE,      0 },

  { "float",            RID_FLOAT,      0 },

  { "for",              RID_FOR,        0 },

  { "friend",           RID_FRIEND,     0 },

  { "goto",             RID_GOTO,       0 },

  { "if",               RID_IF,         0 },

  { "inline",           RID_INLINE,     0 },

  { "int",              RID_INT,        0 },

  { "long",             RID_LONG,       0 },

  { "mutable",          RID_MUTABLE,    0 },

  { "namespace",        RID_NAMESPACE,  0 },

  { "new",              RID_NEW,        0 },

  { "operator",         RID_OPERATOR,   0 },

  { "private",          RID_PRIVATE,    0 },

  { "protected",        RID_PROTECTED,  0 },

  { "public",           RID_PUBLIC,     0 },

  { "register",         RID_REGISTER,   0 },

  { "reinterpret_cast", RID_REINTCAST,  0 },

  { "return",           RID_RETURN,     0 },

  { "short",            RID_SHORT,      0 },

  { "signed",           RID_SIGNED,     0 },

  { "sizeof",           RID_SIZEOF,     0 },

  { "static",           RID_STATIC,     0 },

  { "static_cast",      RID_STATCAST,   0 },

  { "struct",           RID_STRUCT,     0 },

  { "switch",           RID_SWITCH,     0 },

  { "template",         RID_TEMPLATE,   0 },

  { "this",             RID_THIS,       0 },

  { "throw",            RID_THROW,      0 },

  { "true",             RID_TRUE,       0 },

  { "try",              RID_TRY,        0 },

  { "typedef",          RID_TYPEDEF,    0 },

  { "typename",         RID_TYPENAME,   0 },

  { "typeid",           RID_TYPEID,     0 },

  { "typeof",           RID_TYPEOF,     D_ASM|D_EXT },

  { "union",            RID_UNION,      0 },

  { "unsigned",         RID_UNSIGNED,   0 },

  { "using",            RID_USING,      0 },

  { "virtual",          RID_VIRTUAL,    0 },

  { "void",             RID_VOID,       0 },

  { "volatile",         RID_VOLATILE,   0 },

  { "wchar_t",          RID_WCHAR,      0 },

  { "while",            RID_WHILE,      0 },

  /* The remaining keywords are specific to Objective-C++.  NB:

     All of them will remain _disabled_, since they are context-

     sensitive.  */

  /* These ObjC keywords are recognized only immediately after

     an '@'.  NB: The following C++ keywords double as

     ObjC keywords in this context: RID_CLASS, RID_PRIVATE,

     RID_PROTECTED, RID_PUBLIC, RID_THROW, RID_TRY and RID_CATCH.  */

  { "compatibility_alias", RID_AT_ALIAS,        D_OBJC },

  { "defs",             RID_AT_DEFS,            D_OBJC },

  { "encode",           RID_AT_ENCODE,          D_OBJC },

  { "end",              RID_AT_END,             D_OBJC },

  { "implementation",   RID_AT_IMPLEMENTATION,  D_OBJC },

  { "interface",        RID_AT_INTERFACE,       D_OBJC },

  { "protocol",         RID_AT_PROTOCOL,        D_OBJC },

  { "selector",         RID_AT_SELECTOR,        D_OBJC },

  { "finally",          RID_AT_FINALLY,         D_OBJC },

  { "synchronized",     RID_AT_SYNCHRONIZED,    D_OBJC },

  /* These are recognized only in protocol-qualifier context.  */

  { "bycopy",           RID_BYCOPY,             D_OBJC },

  { "byref",            RID_BYREF,              D_OBJC },

  { "in",               RID_IN,                 D_OBJC },

  { "inout",            RID_INOUT,              D_OBJC },

  { "oneway",           RID_ONEWAY,             D_OBJC },

  { "out",              RID_OUT,                D_OBJC },

};

void

init_reswords (void)

{

  unsigned int i;

  tree id;

  int mask = ((flag_no_asm ? D_ASM : 0)

              | D_OBJC

              | (flag_no_gnu_keywords ? D_EXT : 0));

  ridpointers = ggc_calloc ((int) RID_MAX, sizeof (tree));

  for (i = 0; i < ARRAY_SIZE (reswords); i++)

    {

      id = get_identifier (reswords[i].word);

      C_RID_CODE (id) = reswords[i].rid;

      ridpointers [(int) reswords[i].rid] = id;

      if (! (reswords[i].disable & mask))

        C_IS_RESERVED_WORD (id) = 1;

    }

}

static void

init_cp_pragma (void)

{

  c_register_pragma (0, "vtable", handle_pragma_vtable);

  c_register_pragma (0, "unit", handle_pragma_unit);

  c_register_pragma (0, "interface", handle_pragma_interface);

  c_register_pragma (0, "implementation", handle_pragma_implementation);

  c_register_pragma ("GCC", "interface", handle_pragma_interface);

  c_register_pragma ("GCC", "implementation", handle_pragma_implementation);

  c_register_pragma ("GCC", "java_exceptions", handle_pragma_java_exceptions);

}

/* TRUE if a code represents a statement.  */

bool statement_code_p[MAX_TREE_CODES];

/* Initialize the C++ front end.  This function is very sensitive to

   the exact order that things are done here.  It would be nice if the

   initialization done by this routine were moved to its subroutines,

   and the ordering dependencies clarified and reduced.  */

bool

cxx_init (void)

{

  unsigned int i;

  static const enum tree_code stmt_codes[] = {

   CTOR_INITIALIZER,    TRY_BLOCK,      HANDLER,

   EH_SPEC_BLOCK,       USING_STMT,     TAG_DEFN,

   IF_STMT,             CLEANUP_STMT,   FOR_STMT,

   WHILE_STMT,          DO_STMT,        BREAK_STMT,

   CONTINUE_STMT,       SWITCH_STMT,    EXPR_STMT

  };

  memset (&statement_code_p, 0, sizeof (statement_code_p));

  for (i = 0; i < ARRAY_SIZE (stmt_codes); i++)

    statement_code_p[stmt_codes[i]] = true;

  /* We cannot just assign to input_filename because it has already

     been initialized and will be used later as an N_BINCL for stabs+

     debugging.  */

#ifdef USE_MAPPED_LOCATION

  push_srcloc (BUILTINS_LOCATION);

#else

  push_srcloc ("<built-in>", 0);

#endif

  init_reswords ();

  init_tree ();

  init_cp_semantics ();

  init_operators ();

  init_method ();

  init_error ();

  current_function_decl = NULL;

  class_type_node = ridpointers[(int) RID_CLASS];

  cxx_init_decl_processing ();

  /* The fact that G++ uses COMDAT for many entities (inline

     functions, template instantiations, virtual tables, etc.) mean

     that it is fundamentally unreliable to try to make decisions

     about whether or not to output a particular entity until the end

     of the compilation.  However, the inliner requires that functions

     be provided to the back end if they are to be inlined.

     Therefore, we always use unit-at-a-time mode; in that mode, we

     can provide entities to the back end and it will decide what to

     emit based on what is actually needed.  */

  flag_unit_at_a_time = 1;

  if (c_common_init () == false)

    {

      pop_srcloc();

      return false;

    }

  init_cp_pragma ();

  init_repo ();

  pop_srcloc();

  return true;

}

/* Return nonzero if S is not considered part of an

   INTERFACE/IMPLEMENTATION pair.  Otherwise, return 0.  */

static int

interface_strcmp (const char* s)

{

  /* Set the interface/implementation bits for this scope.  */

  struct impl_files *ifiles;

  const char *s1;

  for (ifiles = impl_file_chain; ifiles; ifiles = ifiles->next)

    {

      const char *t1 = ifiles->filename;

      s1 = s;

      if (*s1 != *t1 || *s1 == 0)

        continue;

      while (*s1 == *t1 && *s1 != 0)

        s1++, t1++;

      /* A match.  */

      if (*s1 == *t1)

        return 0;

      /* Don't get faked out by xxx.yyy.cc vs xxx.zzz.cc.  */

      if (strchr (s1, '.') || strchr (t1, '.'))

        continue;

      if (*s1 == '\0' || s1[-1] != '.' || t1[-1] != '.')

        continue;

      /* A match.  */

      return 0;

    }

  /* No matches.  */

  return 1;

}

/* Parse a #pragma whose sole argument is a string constant.

   If OPT is true, the argument is optional.  */

static tree

parse_strconst_pragma (const char* name, int opt)

{

  tree result, x;

  enum cpp_ttype t;

  t = c_lex (&x);

  if (t == CPP_STRING)

    {

      result = x;

      if (c_lex (&x) != CPP_EOF)

        warning (0, "junk at end of #pragma %s", name);

      return result;

    }

  if (t == CPP_EOF && opt)

    return 0;

  error ("invalid #pragma %s", name);

  return (tree)-1;

}

static void

handle_pragma_vtable (cpp_reader* dfile ATTRIBUTE_UNUSED )

{

  parse_strconst_pragma ("vtable", 0);

  sorry ("#pragma vtable no longer supported");

}

static void

handle_pragma_unit (cpp_reader* dfile ATTRIBUTE_UNUSED )

{

  /* Validate syntax, but don't do anything.  */

  parse_strconst_pragma ("unit", 0);

}

static void

handle_pragma_interface (cpp_reader* dfile ATTRIBUTE_UNUSED )

{

  tree fname = parse_strconst_pragma ("interface", 1);

  struct c_fileinfo *finfo;

  const char *filename;

  if (fname == (tree)-1)

    return;

  else if (fname == 0)

    filename = lbasename (input_filename);

  else

    filename = ggc_strdup (TREE_STRING_POINTER (fname));

  finfo = get_fileinfo (filename);

  if (impl_file_chain == 0)

    {

      /* If this is zero at this point, then we are

         auto-implementing.  */

      if (main_input_filename == 0)

        main_input_filename = input_filename;

    }

  finfo->interface_only = interface_strcmp (filename);

  /* If MULTIPLE_SYMBOL_SPACES is set, we cannot assume that we can see

     a definition in another file.  */

  if (!MULTIPLE_SYMBOL_SPACES || !finfo->interface_only)

    finfo->interface_unknown = 0;

}

/* Note that we have seen a #pragma implementation for the key MAIN_FILENAME.

   We used to only allow this at toplevel, but that restriction was buggy

   in older compilers and it seems reasonable to allow it in the headers

   themselves, too.  It only needs to precede the matching #p interface.

   We don't touch finfo->interface_only or finfo->interface_unknown;

   the user must specify a matching #p interface for this to have

   any effect.  */

static void

handle_pragma_implementation (cpp_reader* dfile ATTRIBUTE_UNUSED )

{

  tree fname = parse_strconst_pragma ("implementation", 1);

  const char *filename;

  struct impl_files *ifiles = impl_file_chain;

  if (fname == (tree)-1)

    return;

  if (fname == 0)

    {

      if (main_input_filename)

        filename = main_input_filename;

      else

        filename = input_filename;

      filename = lbasename (filename);

    }

  else

    {

      filename = ggc_strdup (TREE_STRING_POINTER (fname));

#if 0

      /* We currently cannot give this diagnostic, as we reach this point

         only after cpplib has scanned the entire translation unit, so

         cpp_included always returns true.  A plausible fix is to compare

         the current source-location cookie with the first source-location

         cookie (if any) of the filename, but this requires completing the

         --enable-mapped-location project first.  See PR 17577.  */

      if (cpp_included (parse_in, filename))

        warning (0, "#pragma implementation for %qs appears after "

                 "file is included", filename);

#endif

    }

  for (; ifiles; ifiles = ifiles->next)

    {

      if (! strcmp (ifiles->filename, filename))

        break;

    }

  if (ifiles == 0)

    {

      ifiles = xmalloc (sizeof (struct impl_files));

      ifiles->filename = filename;

      ifiles->next = impl_file_chain;

      impl_file_chain = ifiles;

    }

}

/* Indicate that this file uses Java-personality exception handling.  */

static void

handle_pragma_java_exceptions (cpp_reader* dfile ATTRIBUTE_UNUSED )

{

  tree x;

  if (c_lex (&x) != CPP_EOF)

    warning (0, "junk at end of #pragma GCC java_exceptions");

  choose_personality_routine (lang_java);

}

/* Issue an error message indicating that the lookup of NAME (an

   IDENTIFIER_NODE) failed.  Returns the ERROR_MARK_NODE.  */

tree

unqualified_name_lookup_error (tree name)

{

  if (IDENTIFIER_OPNAME_P (name))

    {

      if (name != ansi_opname (ERROR_MARK))

        error ("%qD not defined", name);

    }

  else

    {

      error ("%qD was not declared in this scope", name);

      /* Prevent repeated error messages by creating a VAR_DECL with

         this NAME in the innermost block scope.  */

      if (current_function_decl)

        {

          tree decl;

          decl = build_decl (VAR_DECL, name, error_mark_node);

          DECL_CONTEXT (decl) = current_function_decl;

          push_local_binding (name, decl, 0);

          /* Mark the variable as used so that we do not get warnings

             about it being unused later.  */

          TREE_USED (decl) = 1;

        }

    }

  return error_mark_node;

}

/* Like unqualified_name_lookup_error, but NAME is an unqualified-id

   used as a function.  Returns an appropriate expression for

   NAME.  */

tree

unqualified_fn_lookup_error (tree name)

{

  if (processing_template_decl)

    {

      /* In a template, it is invalid to write "f()" or "f(3)" if no

         declaration of "f" is available.  Historically, G++ and most

         other compilers accepted that usage since they deferred all name

         lookup until instantiation time rather than doing unqualified

         name lookup at template definition time; explain to the user what

         is going wrong.

         Note that we have the exact wording of the following message in

         the manual (trouble.texi, node "Name lookup"), so they need to

         be kept in synch.  */

      pedwarn ("there are no arguments to %qD that depend on a template "

               "parameter, so a declaration of %qD must be available",

               name, name);

      if (!flag_permissive)

        {

          static bool hint;