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/* Internal type definitions for GDB.

   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,

   2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010

   Free Software Foundation, Inc.

   Contributed by Cygnus Support, using pieces from other GDB modules.

   This file is part of GDB.

   This program 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 3 of the License, or

   (at your option) any later version.

   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.  */

#if !defined (GDBTYPES_H)

#define GDBTYPES_H 1

#include "hashtab.h"

/* Forward declarations for prototypes.  */

struct field;

struct block;

struct value_print_options;

struct language_defn;

/* Some macros for char-based bitfields.  */

#define B_SET(a,x)      ((a)[(x)>>3] |= (1 << ((x)&7)))

#define B_CLR(a,x)      ((a)[(x)>>3] &= ~(1 << ((x)&7)))

#define B_TST(a,x)      ((a)[(x)>>3] & (1 << ((x)&7)))

#define B_TYPE          unsigned char

#define B_BYTES(x)      ( 1 + ((x)>>3) )

#define B_CLRALL(a,x)   memset ((a), 0, B_BYTES(x))

/* Different kinds of data types are distinguished by the `code' field.  */

enum type_code

  {

    TYPE_CODE_UNDEF,            /* Not used; catches errors */

    TYPE_CODE_PTR,              /* Pointer type */

    /* Array type with lower & upper bounds.

       Regardless of the language, GDB represents multidimensional

       array types the way C does: as arrays of arrays.  So an

       instance of a GDB array type T can always be seen as a series

       of instances of TYPE_TARGET_TYPE (T) laid out sequentially in

       memory.

       Row-major languages like C lay out multi-dimensional arrays so

       that incrementing the rightmost index in a subscripting

       expression results in the smallest change in the address of the

       element referred to.  Column-major languages like Fortran lay

       them out so that incrementing the leftmost index results in the

       smallest change.

       This means that, in column-major languages, working our way

       from type to target type corresponds to working through indices

       from right to left, not left to right.  */

    TYPE_CODE_ARRAY,

    TYPE_CODE_STRUCT,           /* C struct or Pascal record */

    TYPE_CODE_UNION,            /* C union or Pascal variant part */

    TYPE_CODE_ENUM,             /* Enumeration type */

    TYPE_CODE_FLAGS,            /* Bit flags type */

    TYPE_CODE_FUNC,             /* Function type */

    TYPE_CODE_INT,              /* Integer type */

    /* Floating type.  This is *NOT* a complex type.  Beware, there are parts

       of GDB which bogusly assume that TYPE_CODE_FLT can mean complex.  */

    TYPE_CODE_FLT,

    /* Void type.  The length field specifies the length (probably always

       one) which is used in pointer arithmetic involving pointers to

       this type, but actually dereferencing such a pointer is invalid;

       a void type has no length and no actual representation in memory

       or registers.  A pointer to a void type is a generic pointer.  */

    TYPE_CODE_VOID,

    TYPE_CODE_SET,              /* Pascal sets */

    TYPE_CODE_RANGE,            /* Range (integers within spec'd bounds) */

    /* A string type which is like an array of character but prints

       differently (at least for (the deleted) CHILL).  It does not

       contain a length field as Pascal strings (for many Pascals,

       anyway) do; if we want to deal with such strings, we should use

       a new type code.  */

    TYPE_CODE_STRING,

    /* String of bits; like TYPE_CODE_SET but prints differently (at

       least for (the deleted) CHILL).  */

    TYPE_CODE_BITSTRING,

    /* Unknown type.  The length field is valid if we were able to

       deduce that much about the type, or 0 if we don't even know that.  */

    TYPE_CODE_ERROR,

    /* C++ */

    TYPE_CODE_METHOD,           /* Method type */

    /* Pointer-to-member-function type.  This describes how to access a

       particular member function of a class (possibly a virtual

       member function).  The representation may vary between different

       C++ ABIs.  */

    TYPE_CODE_METHODPTR,

    /* Pointer-to-member type.  This is the offset within a class to some

       particular data member.  The only currently supported representation

       uses an unbiased offset, with -1 representing NULL; this is used

       by the Itanium C++ ABI (used by GCC on all platforms).  */

    TYPE_CODE_MEMBERPTR,

    TYPE_CODE_REF,              /* C++ Reference types */

    TYPE_CODE_CHAR,             /* *real* character type */

    /* Boolean type.  0 is false, 1 is true, and other values are non-boolean

       (e.g. FORTRAN "logical" used as unsigned int).  */

    TYPE_CODE_BOOL,

    /* Fortran */

    TYPE_CODE_COMPLEX,          /* Complex float */

    TYPE_CODE_TYPEDEF,

    TYPE_CODE_NAMESPACE,        /* C++ namespace.  */

    TYPE_CODE_DECFLOAT,         /* Decimal floating point.  */

    TYPE_CODE_MODULE,           /* Fortran module.  */

    /* Internal function type.  */

    TYPE_CODE_INTERNAL_FUNCTION

  };

/* For now allow source to use TYPE_CODE_CLASS for C++ classes, as an

   alias for TYPE_CODE_STRUCT.  This is for DWARF, which has a distinct

   "class" attribute.  Perhaps we should actually have a separate TYPE_CODE

   so that we can print "class" or "struct" depending on what the debug

   info said.  It's not clear we should bother.  */

#define TYPE_CODE_CLASS TYPE_CODE_STRUCT

/* Some constants representing each bit field in the main_type.  See

   the bit-field-specific macros, below, for documentation of each

   constant in this enum.  These enum values are only used with

   init_type.  Note that the values are chosen not to conflict with

   type_instance_flag_value; this lets init_type error-check its

   input.  */

enum type_flag_value

{

  TYPE_FLAG_UNSIGNED = (1 << 6),

  TYPE_FLAG_NOSIGN = (1 << 7),

  TYPE_FLAG_STUB = (1 << 8),

  TYPE_FLAG_TARGET_STUB = (1 << 9),

  TYPE_FLAG_STATIC = (1 << 10),

  TYPE_FLAG_PROTOTYPED = (1 << 11),

  TYPE_FLAG_INCOMPLETE = (1 << 12),

  TYPE_FLAG_VARARGS = (1 << 13),

  TYPE_FLAG_VECTOR = (1 << 14),

  TYPE_FLAG_FIXED_INSTANCE = (1 << 15),

  TYPE_FLAG_STUB_SUPPORTED = (1 << 16),

  TYPE_FLAG_NOTTEXT = (1 << 17),

  /* Used for error-checking.  */

  TYPE_FLAG_MIN = TYPE_FLAG_UNSIGNED

};

/* Some bits for the type's instance_flags word.  See the macros below

   for documentation on each bit.  Note that if you add a value here,

   you must update the enum type_flag_value as well.  */

enum type_instance_flag_value

{

  TYPE_INSTANCE_FLAG_CONST = (1 << 0),

  TYPE_INSTANCE_FLAG_VOLATILE = (1 << 1),

  TYPE_INSTANCE_FLAG_CODE_SPACE = (1 << 2),

  TYPE_INSTANCE_FLAG_DATA_SPACE = (1 << 3),

  TYPE_INSTANCE_FLAG_ADDRESS_CLASS_1 = (1 << 4),

  TYPE_INSTANCE_FLAG_ADDRESS_CLASS_2 = (1 << 5)

};

/* Unsigned integer type.  If this is not set for a TYPE_CODE_INT, the

   type is signed (unless TYPE_FLAG_NOSIGN (below) is set). */

#define TYPE_UNSIGNED(t)        (TYPE_MAIN_TYPE (t)->flag_unsigned)

/* No sign for this type.  In C++, "char", "signed char", and "unsigned

   char" are distinct types; so we need an extra flag to indicate the

   absence of a sign! */

#define TYPE_NOSIGN(t)          (TYPE_MAIN_TYPE (t)->flag_nosign)

/* This appears in a type's flags word if it is a stub type (e.g., if

   someone referenced a type that wasn't defined in a source file

   via (struct sir_not_appearing_in_this_film *)).  */

#define TYPE_STUB(t)            (TYPE_MAIN_TYPE (t)->flag_stub)

/* The target type of this type is a stub type, and this type needs to

   be updated if it gets un-stubbed in check_typedef.

   Used for arrays and ranges, in which TYPE_LENGTH of the array/range

   gets set based on the TYPE_LENGTH of the target type.

   Also, set for TYPE_CODE_TYPEDEF. */

#define TYPE_TARGET_STUB(t)     (TYPE_MAIN_TYPE (t)->flag_target_stub)

/* Static type.  If this is set, the corresponding type had

 * a static modifier.

 * Note: This may be unnecessary, since static data members

 * are indicated by other means (bitpos == -1)

 */

#define TYPE_STATIC(t)          (TYPE_MAIN_TYPE (t)->flag_static)

/* This is a function type which appears to have a prototype.  We need this

   for function calls in order to tell us if it's necessary to coerce the args,

   or to just do the standard conversions.  This is used with a short field. */

#define TYPE_PROTOTYPED(t)      (TYPE_MAIN_TYPE (t)->flag_prototyped)

/* This flag is used to indicate that processing for this type

   is incomplete.

   (Mostly intended for HP platforms, where class methods, for

   instance, can be encountered before their classes in the debug

   info; the incomplete type has to be marked so that the class and

   the method can be assigned correct types.) */

#define TYPE_INCOMPLETE(t)      (TYPE_MAIN_TYPE (t)->flag_incomplete)

/* FIXME drow/2002-06-03:  Only used for methods, but applies as well

   to functions.  */

#define TYPE_VARARGS(t)         (TYPE_MAIN_TYPE (t)->flag_varargs)

/* Identify a vector type.  Gcc is handling this by adding an extra

   attribute to the array type.  We slurp that in as a new flag of a

   type.  This is used only in dwarf2read.c.  */

#define TYPE_VECTOR(t)          (TYPE_MAIN_TYPE (t)->flag_vector)

/* The debugging formats (especially STABS) do not contain enough information

   to represent all Ada types---especially those whose size depends on

   dynamic quantities.  Therefore, the GNAT Ada compiler includes

   extra information in the form of additional type definitions

   connected by naming conventions.  This flag indicates that the

   type is an ordinary (unencoded) GDB type that has been created from

   the necessary run-time information, and does not need further

   interpretation. Optionally marks ordinary, fixed-size GDB type. */

#define TYPE_FIXED_INSTANCE(t) (TYPE_MAIN_TYPE (t)->flag_fixed_instance)

/* This debug target supports TYPE_STUB(t).  In the unsupported case we have to

   rely on NFIELDS to be zero etc., see TYPE_IS_OPAQUE ().

   TYPE_STUB(t) with !TYPE_STUB_SUPPORTED(t) may exist if we only guessed

   the TYPE_STUB(t) value (see dwarfread.c).  */

#define TYPE_STUB_SUPPORTED(t)   (TYPE_MAIN_TYPE (t)->flag_stub_supported)

/* Not textual.  By default, GDB treats all single byte integers as

   characters (or elements of strings) unless this flag is set.  */

#define TYPE_NOTTEXT(t)         (TYPE_MAIN_TYPE (t)->flag_nottext)

/* Type owner.  If TYPE_OBJFILE_OWNED is true, the type is owned by

   the objfile retrieved as TYPE_OBJFILE.  Otherweise, the type is

   owned by an architecture; TYPE_OBJFILE is NULL in this case.  */

#define TYPE_OBJFILE_OWNED(t) (TYPE_MAIN_TYPE (t)->flag_objfile_owned)

#define TYPE_OWNER(t) TYPE_MAIN_TYPE(t)->owner

#define TYPE_OBJFILE(t) (TYPE_OBJFILE_OWNED(t)? TYPE_OWNER(t).objfile : NULL)

/* True if this type was declared using the "class" keyword.  This is

   only valid for C++ structure types, and only used for displaying

   the type.  If false, the structure was declared as a "struct".  */

#define TYPE_DECLARED_CLASS(t) (TYPE_MAIN_TYPE (t)->flag_declared_class)

/* Constant type.  If this is set, the corresponding type has a

 * const modifier.

 */

#define TYPE_CONST(t) (TYPE_INSTANCE_FLAGS (t) & TYPE_INSTANCE_FLAG_CONST)

/* Volatile type.  If this is set, the corresponding type has a

 * volatile modifier.

 */

#define TYPE_VOLATILE(t) (TYPE_INSTANCE_FLAGS (t) & TYPE_INSTANCE_FLAG_VOLATILE)

/* Instruction-space delimited type.  This is for Harvard architectures

   which have separate instruction and data address spaces (and perhaps

   others).

   GDB usually defines a flat address space that is a superset of the

   architecture's two (or more) address spaces, but this is an extension

   of the architecture's model.

   If TYPE_FLAG_INST is set, an object of the corresponding type

   resides in instruction memory, even if its address (in the extended

   flat address space) does not reflect this.

   Similarly, if TYPE_FLAG_DATA is set, then an object of the

   corresponding type resides in the data memory space, even if

   this is not indicated by its (flat address space) address.

   If neither flag is set, the default space for functions / methods

   is instruction space, and for data objects is data memory.  */

#define TYPE_CODE_SPACE(t) \

  (TYPE_INSTANCE_FLAGS (t) & TYPE_INSTANCE_FLAG_CODE_SPACE)

#define TYPE_DATA_SPACE(t) \

  (TYPE_INSTANCE_FLAGS (t) & TYPE_INSTANCE_FLAG_DATA_SPACE)

/* Address class flags.  Some environments provide for pointers whose

   size is different from that of a normal pointer or address types

   where the bits are interpreted differently than normal addresses.  The

   TYPE_FLAG_ADDRESS_CLASS_n flags may be used in target specific

   ways to represent these different types of address classes.  */

#define TYPE_ADDRESS_CLASS_1(t) (TYPE_INSTANCE_FLAGS(t) \

                                 & TYPE_INSTANCE_FLAG_ADDRESS_CLASS_1)

#define TYPE_ADDRESS_CLASS_2(t) (TYPE_INSTANCE_FLAGS(t) \

                                 & TYPE_INSTANCE_FLAG_ADDRESS_CLASS_2)

#define TYPE_INSTANCE_FLAG_ADDRESS_CLASS_ALL \

  (TYPE_INSTANCE_FLAG_ADDRESS_CLASS_1 | TYPE_INSTANCE_FLAG_ADDRESS_CLASS_2)

#define TYPE_ADDRESS_CLASS_ALL(t) (TYPE_INSTANCE_FLAGS(t) \

                                   & TYPE_INSTANCE_FLAG_ADDRESS_CLASS_ALL)

/* Determine which field of the union main_type.fields[x].loc is used.  */

enum field_loc_kind

  {

    FIELD_LOC_KIND_BITPOS,      /* bitpos */

    FIELD_LOC_KIND_PHYSADDR,    /* physaddr */

    FIELD_LOC_KIND_PHYSNAME     /* physname */

  };

/* A discriminant to determine which field in the main_type.type_specific

   union is being used, if any.

   For types such as TYPE_CODE_FLT or TYPE_CODE_FUNC, the use of this

   discriminant is really redundant, as we know from the type code

   which field is going to be used.  As such, it would be possible to

   reduce the size of this enum in order to save a bit or two for

   other fields of struct main_type.  But, since we still have extra

   room , and for the sake of clarity and consistency, we treat all fields

   of the union the same way.  */

enum type_specific_kind

{

  TYPE_SPECIFIC_NONE,

  TYPE_SPECIFIC_CPLUS_STUFF,

  TYPE_SPECIFIC_GNAT_STUFF,

  TYPE_SPECIFIC_FLOATFORMAT,

  TYPE_SPECIFIC_CALLING_CONVENTION

};

/* This structure is space-critical.

   Its layout has been tweaked to reduce the space used.  */

struct main_type

{

  /* Code for kind of type */

  ENUM_BITFIELD(type_code) code : 8;

  /* Flags about this type.  These fields appear at this location

     because they packs nicely here.  See the TYPE_* macros for

     documentation about these fields.  */

  unsigned int flag_unsigned : 1;

  unsigned int flag_nosign : 1;

  unsigned int flag_stub : 1;

  unsigned int flag_target_stub : 1;

  unsigned int flag_static : 1;

  unsigned int flag_prototyped : 1;

  unsigned int flag_incomplete : 1;

  unsigned int flag_varargs : 1;

  unsigned int flag_vector : 1;

  unsigned int flag_stub_supported : 1;

  unsigned int flag_nottext : 1;

  unsigned int flag_fixed_instance : 1;

  unsigned int flag_objfile_owned : 1;

  /* True if this type was declared with "class" rather than

     "struct".  */

  unsigned int flag_declared_class : 1;

  /* A discriminant telling us which field of the type_specific union

     is being used for this type, if any.  */

  ENUM_BITFIELD(type_specific_kind) type_specific_field : 3;

  /* Number of fields described for this type.  This field appears at

     this location because it packs nicely here.  */

  short nfields;

  /* Field number of the virtual function table pointer in

     VPTR_BASETYPE.  If -1, we were unable to find the virtual

     function table pointer in initial symbol reading, and

     get_vptr_fieldno should be called to find it if possible.

     get_vptr_fieldno will update this field if possible.

     Otherwise the value is left at -1.

     Unused if this type does not have virtual functions.

     This field appears at this location because it packs nicely here.  */

  short vptr_fieldno;

  /* Name of this type, or NULL if none.

     This is used for printing only, except by poorly designed C++ code.

     For looking up a name, look for a symbol in the VAR_DOMAIN.  */

  char *name;

  /* Tag name for this type, or NULL if none.  This means that the

     name of the type consists of a keyword followed by the tag name.

     Which keyword is determined by the type code ("struct" for

     TYPE_CODE_STRUCT, etc.).  As far as I know C/C++ are the only languages

     with this feature.

     This is used for printing only, except by poorly designed C++ code.

     For looking up a name, look for a symbol in the STRUCT_DOMAIN.

     One more legitimate use is that if TYPE_FLAG_STUB is set, this is

     the name to use to look for definitions in other files.  */

  char *tag_name;

  /* Every type is now associated with a particular objfile, and the

     type is allocated on the objfile_obstack for that objfile.  One problem

     however, is that there are times when gdb allocates new types while

     it is not in the process of reading symbols from a particular objfile.

     Fortunately, these happen when the type being created is a derived

     type of an existing type, such as in lookup_pointer_type().  So

     we can just allocate the new type using the same objfile as the

     existing type, but to do this we need a backpointer to the objfile

     from the existing type.  Yes this is somewhat ugly, but without

     major overhaul of the internal type system, it can't be avoided

     for now. */

  union type_owner

    {

      struct objfile *objfile;

      struct gdbarch *gdbarch;

    } owner;

  /* For a pointer type, describes the type of object pointed to.

     For an array type, describes the type of the elements.

     For a function or method type, describes the type of the return value.

     For a range type, describes the type of the full range.

     For a complex type, describes the type of each coordinate.

     For a special record or union type encoding a dynamic-sized type

     in GNAT, a memoized pointer to a corresponding static version of

     the type.

     Unused otherwise.  */

  struct type *target_type;

  /* For structure and union types, a description of each field.

     For set and pascal array types, there is one "field",

     whose type is the domain type of the set or array.

     For range types, there are two "fields",

     the minimum and maximum values (both inclusive).

     For enum types, each possible value is described by one "field".

     For a function or method type, a "field" for each parameter.

     For C++ classes, there is one field for each base class (if it is

     a derived class) plus one field for each class data member.  Member

     functions are recorded elsewhere.

     Using a pointer to a separate array of fields

     allows all types to have the same size, which is useful

     because we can allocate the space for a type before

     we know what to put in it.  */

  union

  {

    struct field

    {

      union field_location

      {

        /* Position of this field, counting in bits from start of

           containing structure.

           For gdbarch_bits_big_endian=1 targets, it is the bit offset to the MSB.

           For gdbarch_bits_big_endian=0 targets, it is the bit offset to the LSB.

           For a range bound or enum value, this is the value itself. */

        int bitpos;

        /* For a static field, if TYPE_FIELD_STATIC_HAS_ADDR then physaddr

           is the location (in the target) of the static field.

           Otherwise, physname is the mangled label of the static field. */

        CORE_ADDR physaddr;

        char *physname;

      }

      loc;

      /* For a function or member type, this is 1 if the argument is marked

         artificial.  Artificial arguments should not be shown to the

         user.  For TYPE_CODE_RANGE it is set if the specific bound is not

         defined.  */

      unsigned int artificial : 1;

      /* Discriminant for union field_location.  */

      ENUM_BITFIELD(field_loc_kind) loc_kind : 2;

      /* Size of this field, in bits, or zero if not packed.

         If non-zero in an array type, indicates the element size in

         bits (used only in Ada at the moment).

         For an unpacked field, the field's type's length

         says how many bytes the field occupies.  */

      unsigned int bitsize : 29;

      /* In a struct or union type, type of this field.

         In a function or member type, type of this argument.

         In an array type, the domain-type of the array.  */

      struct type *type;

      /* Name of field, value or argument.

         NULL for range bounds, array domains, and member function

         arguments.  */

      char *name;

    } *fields;

    /* Union member used for range types. */

    struct range_bounds

    {

      /* Low bound of range. */

      LONGEST low;

      /* High bound of range. */

      LONGEST high;

      /* Flags indicating whether the values of low and high are

         valid.  When true, the respective range value is

         undefined.  Currently used only for FORTRAN arrays.  */

      char low_undefined;

      char high_undefined;

    } *bounds;

  } flds_bnds;

  /* For types with virtual functions (TYPE_CODE_STRUCT), VPTR_BASETYPE

     is the base class which defined the virtual function table pointer.

     For types that are pointer to member types (TYPE_CODE_METHODPTR,

     TYPE_CODE_MEMBERPTR), VPTR_BASETYPE is the type that this pointer

     is a member of.

     For method types (TYPE_CODE_METHOD), VPTR_BASETYPE is the aggregate

     type that contains the method.

     Unused otherwise.  */

  struct type *vptr_basetype;

  /* Slot to point to additional language-specific fields of this type.  */

  union type_specific

  {

    /* CPLUS_STUFF is for TYPE_CODE_STRUCT.  It is initialized to point to

       cplus_struct_default, a default static instance of a struct

       cplus_struct_type. */

    struct cplus_struct_type *cplus_stuff;

    /* GNAT_STUFF is for types for which the GNAT Ada compiler

       provides additional information.  */

    struct gnat_aux_type *gnat_stuff;

    /* FLOATFORMAT is for TYPE_CODE_FLT.  It is a pointer to two

       floatformat objects that describe the floating-point value

       that resides within the type.  The first is for big endian

       targets and the second is for little endian targets.  */

    const struct floatformat **floatformat;

    /* For TYPE_CODE_FUNC types, the calling convention for targets

       supporting multiple ABIs.  Right now this is only fetched from

       the Dwarf-2 DW_AT_calling_convention attribute.  */

    unsigned calling_convention;

  } type_specific;

};

/* A ``struct type'' describes a particular instance of a type, with

   some particular qualification.  */

struct type

{

  /* Type that is a pointer to this type.

     NULL if no such pointer-to type is known yet.

     The debugger may add the address of such a type

     if it has to construct one later.  */

  struct type *pointer_type;

  /* C++: also need a reference type.  */

  struct type *reference_type;

  /* Variant chain.  This points to a type that differs from this one only

     in qualifiers and length.  Currently, the possible qualifiers are

     const, volatile, code-space, data-space, and address class.  The

     length may differ only when one of the address class flags are set.

     The variants are linked in a circular ring and share MAIN_TYPE.  */

  struct type *chain;

  /* Flags specific to this instance of the type, indicating where

     on the ring we are.  */

  int instance_flags;

  /* Length of storage for a value of this type.  This is what

     sizeof(type) would return; use it for address arithmetic,

     memory reads and writes, etc.  This size includes padding.  For

     example, an i386 extended-precision floating point value really

     only occupies ten bytes, but most ABI's declare its size to be

     12 bytes, to preserve alignment.  A `struct type' representing

     such a floating-point type would have a `length' value of 12,

     even though the last two bytes are unused.

     There's a bit of a host/target mess here, if you're concerned

     about machines whose bytes aren't eight bits long, or who don't

     have byte-addressed memory.  Various places pass this to memcpy

     and such, meaning it must be in units of host bytes.  Various

     other places expect they can calculate addresses by adding it

     and such, meaning it must be in units of target bytes.  For

     some DSP targets, in which HOST_CHAR_BIT will (presumably) be 8

     and TARGET_CHAR_BIT will be (say) 32, this is a problem.

     One fix would be to make this field in bits (requiring that it

     always be a multiple of HOST_CHAR_BIT and TARGET_CHAR_BIT) ---

     the other choice would be to make it consistently in units of

     HOST_CHAR_BIT.  However, this would still fail to address

     machines based on a ternary or decimal representation.  */

  unsigned length;

  /* Core type, shared by a group of qualified types.  */

  struct main_type *main_type;

};

#define NULL_TYPE ((struct type *) 0)

/* C++ language-specific information for TYPE_CODE_STRUCT and TYPE_CODE_UNION

   nodes.  */

struct cplus_struct_type

  {

    /* Number of base classes this type derives from.  The baseclasses are

       stored in the first N_BASECLASSES fields (i.e. the `fields' field of

       the struct type).  I think only the `type' field of such a field has

       any meaning.  */

    short n_baseclasses;

    /* Number of methods with unique names.  All overloaded methods with

       the same name count only once. */

    short nfn_fields;

    /* Number of methods described for this type, not including the

       methods that it derives from.  */

    short nfn_fields_total;

    /* One if this struct is a dynamic class, as defined by the

       Itanium C++ ABI: if it requires a virtual table pointer,

       because it or any of its base classes have one or more virtual

       member functions or virtual base classes.  Minus one if not

       dynamic.  Zero if not yet computed.  */

    int is_dynamic : 2;

    /* For derived classes, the number of base classes is given by n_baseclasses

       and virtual_field_bits is a bit vector containing one bit per base class.

       If the base class is virtual, the corresponding bit will be set.

       I.E, given:

       class A{};

       class B{};

       class C : public B, public virtual A {};

       B is a baseclass of C; A is a virtual baseclass for C.

       This is a C++ 2.0 language feature. */

    B_TYPE *virtual_field_bits;

    /* For classes with private fields, the number of fields is given by

       nfields and private_field_bits is a bit vector containing one bit

       per field.

       If the field is private, the corresponding bit will be set. */

    B_TYPE *private_field_bits;

    /* For classes with protected fields, the number of fields is given by

       nfields and protected_field_bits is a bit vector containing one bit

       per field.

       If the field is private, the corresponding bit will be set. */

    B_TYPE *protected_field_bits;

    /* for classes with fields to be ignored, either this is optimized out

       or this field has length 0 */

    B_TYPE *ignore_field_bits;

    /* For classes, structures, and unions, a description of each field,

       which consists of an overloaded name, followed by the types of

       arguments that the method expects, and then the name after it

       has been renamed to make it distinct.

       fn_fieldlists points to an array of nfn_fields of these. */

    struct fn_fieldlist

      {

        /* The overloaded name.  */

        char *name;

        /* The number of methods with this name.  */

        int length;

        /* The list of methods.  */

        struct fn_field

          {

            /* If is_stub is clear, this is the mangled name which we can

               look up to find the address of the method (FIXME: it would

               be cleaner to have a pointer to the struct symbol here

               instead).  */

            /* If is_stub is set, this is the portion of the mangled

               name which specifies the arguments.  For example, "ii",

               if there are two int arguments, or "" if there are no

               arguments.  See gdb_mangle_name for the conversion from this

               format to the one used if is_stub is clear.  */

            char *physname;

            /* The function type for the method.

               (This comment used to say "The return value of the method",

               but that's wrong. The function type

               is expected here, i.e. something with TYPE_CODE_FUNC,

               and *not* the return-value type). */

            struct type *type;

            /* For virtual functions.

               First baseclass that defines this virtual function.   */

            struct type *fcontext;

            /* Attributes. */

            unsigned int is_const:1;

            unsigned int is_volatile:1;

            unsigned int is_private:1;

            unsigned int is_protected:1;

            unsigned int is_public:1;

            unsigned int is_abstract:1;

            unsigned int is_static:1;

            unsigned int is_final:1;

            unsigned int is_synchronized:1;

            unsigned int is_native:1;

            unsigned int is_artificial:1;

            /* A stub method only has some fields valid (but they are enough

               to reconstruct the rest of the fields).  */

            unsigned int is_stub:1;

            /* Unused.  */

            unsigned int dummy:4;

            /* Index into that baseclass's virtual function table,

               minus 2; else if static: VOFFSET_STATIC; else: 0.  */

            unsigned int voffset:16;

#define VOFFSET_STATIC 1

          }

         *fn_fields;

      }

     *fn_fieldlists;

    /* Pointer to information about enclosing scope, if this is a

     * local type.  If it is not a local type, this is NULL

     */

    struct local_type_info

      {

        char *file;

        int line;

      }

     *localtype_ptr;

    /* typedefs defined inside this class.  TYPEDEF_FIELD points to an array of

       TYPEDEF_FIELD_COUNT elements.  */

    struct typedef_field

      {

        /* Unqualified name to be prefixed by owning class qualified name.  */

        const char *name;

        /* Type this typedef named NAME represents.  */

        struct type *type;

      }

    *typedef_field;

    unsigned typedef_field_count;

  };

/* Struct used in computing virtual base list */

struct vbase

  {

    struct type *vbasetype;     /* pointer to virtual base */

    struct vbase *next;         /* next in chain */

  };

/* Struct used for ranking a function for overload resolution */