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2.7.4 typedef asymbol

An asymbol has the form:

 
typedef struct symbol_cache_entry
{
  /* A pointer to the BFD which owns the symbol. This information
     is necessary so that a back end can work out what additional
     information (invisible to the application writer) is carried
     with the symbol.

     This field is *almost* redundant, since you can use section->owner
     instead, except that some symbols point to the global sections
     bfd_{abs,com,und}_section.  This could be fixed by making
     these globals be per-bfd (or per-target-flavor).  FIXME.  */
  struct _bfd *the_bfd; /* Use bfd_asymbol_bfd(sym) to access this field.  */

  /* The text of the symbol. The name is left alone, and not copied; the
     application may not alter it.  */
  const char *name;

  /* The value of the symbol.  This really should be a union of a
     numeric value with a pointer, since some flags indicate that
     a pointer to another symbol is stored here.  */
  symvalue value;

  /* Attributes of a symbol.  */
#define BSF_NO_FLAGS    0x00

  /* The symbol has local scope; static in C. The value
     is the offset into the section of the data.  */
#define BSF_LOCAL      0x01

  /* The symbol has global scope; initialized data in C. The
     value is the offset into the section of the data.  */
#define BSF_GLOBAL     0x02

  /* The symbol has global scope and is exported. The value is
     the offset into the section of the data.  */
#define BSF_EXPORT     BSF_GLOBAL /* No real difference.  */

  /* A normal C symbol would be one of:
     BSF_LOCAL, BSF_FORT_COMM,  BSF_UNDEFINED or
     BSF_GLOBAL.  */

  /* The symbol is a debugging record. The value has an arbitary
     meaning, unless BSF_DEBUGGING_RELOC is also set.  */
#define BSF_DEBUGGING  0x08

  /* The symbol denotes a function entry point.  Used in ELF,
     perhaps others someday.  */
#define BSF_FUNCTION    0x10

  /* Used by the linker.  */
#define BSF_KEEP        0x20
#define BSF_KEEP_G      0x40

  /* A weak global symbol, overridable without warnings by
     a regular global symbol of the same name.  */
#define BSF_WEAK        0x80

  /* This symbol was created to point to a section, e.g. ELF's
     STT_SECTION symbols.  */
#define BSF_SECTION_SYM 0x100

  /* The symbol used to be a common symbol, but now it is
     allocated.  */
#define BSF_OLD_COMMON  0x200

  /* The default value for common data.  */
#define BFD_FORT_COMM_DEFAULT_VALUE 0

  /* In some files the type of a symbol sometimes alters its
     location in an output file - ie in coff a ISFCN symbol
     which is also C_EXT symbol appears where it was
     declared and not at the end of a section.  This bit is set
     by the target BFD part to convey this information.  */
#define BSF_NOT_AT_END    0x400

  /* Signal that the symbol is the label of constructor section.  */
#define BSF_CONSTRUCTOR   0x800

  /* Signal that the symbol is a warning symbol.  The name is a
     warning.  The name of the next symbol is the one to warn about;
     if a reference is made to a symbol with the same name as the next
     symbol, a warning is issued by the linker.  */
#define BSF_WARNING       0x1000

  /* Signal that the symbol is indirect.  This symbol is an indirect
     pointer to the symbol with the same name as the next symbol.  */
#define BSF_INDIRECT      0x2000

  /* BSF_FILE marks symbols that contain a file name.  This is used
     for ELF STT_FILE symbols.  */
#define BSF_FILE          0x4000

  /* Symbol is from dynamic linking information.  */
#define BSF_DYNAMIC       0x8000

  /* The symbol denotes a data object.  Used in ELF, and perhaps
     others someday.  */
#define BSF_OBJECT        0x10000

  /* This symbol is a debugging symbol.  The value is the offset
     into the section of the data.  BSF_DEBUGGING should be set
     as well.  */
#define BSF_DEBUGGING_RELOC 0x20000

  /* This symbol is thread local.  Used in ELF.  */
#define BSF_THREAD_LOCAL  0x40000

  flagword flags;

  /* A pointer to the section to which this symbol is
     relative.  This will always be non NULL, there are special
     sections for undefined and absolute symbols.  */
  struct sec *section;

  /* Back end special data.  */
  union
    {
      PTR p;
      bfd_vma i;
    }
  udata;
}
asymbol;


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