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2.7.4 typedef asymbol

An asymbol has the form:


typedef struct bfd_symbol
{
  /* 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              (1 << 0)

  /* The symbol has global scope; initialized data in C. The
     value is the offset into the section of the data.  */
#define BSF_GLOBAL             (1 << 1)

  /* 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_UNDEFINED or BSF_GLOBAL.  */

  /* The symbol is a debugging record. The value has an arbitrary
     meaning, unless BSF_DEBUGGING_RELOC is also set.  */
#define BSF_DEBUGGING          (1 << 2)

  /* The symbol denotes a function entry point.  Used in ELF,
     perhaps others someday.  */
#define BSF_FUNCTION           (1 << 3)

  /* Used by the linker.  */
#define BSF_KEEP               (1 << 5)

  /* An ELF common symbol.  */
#define BSF_ELF_COMMON         (1 << 6)

  /* A weak global symbol, overridable without warnings by
     a regular global symbol of the same name.  */
#define BSF_WEAK               (1 << 7)

  /* This symbol was created to point to a section, e.g. ELF's
     STT_SECTION symbols.  */
#define BSF_SECTION_SYM        (1 << 8)

  /* The symbol used to be a common symbol, but now it is
     allocated.  */
#define BSF_OLD_COMMON         (1 << 9)

  /* 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         (1 << 10)

  /* Signal that the symbol is the label of constructor section.  */
#define BSF_CONSTRUCTOR        (1 << 11)

  /* 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            (1 << 12)

  /* 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           (1 << 13)

  /* BSF_FILE marks symbols that contain a file name.  This is used
     for ELF STT_FILE symbols.  */
#define BSF_FILE               (1 << 14)

  /* Symbol is from dynamic linking information.  */
#define BSF_DYNAMIC            (1 << 15)

  /* The symbol denotes a data object.  Used in ELF, and perhaps
     others someday.  */
#define BSF_OBJECT             (1 << 16)

  /* 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    (1 << 17)

  /* This symbol is thread local.  Used in ELF.  */
#define BSF_THREAD_LOCAL       (1 << 18)

  /* This symbol represents a complex relocation expression,
     with the expression tree serialized in the symbol name.  */
#define BSF_RELC               (1 << 19)

  /* This symbol represents a signed complex relocation expression,
     with the expression tree serialized in the symbol name.  */
#define BSF_SRELC              (1 << 20)

  /* This symbol was created by bfd_get_synthetic_symtab.  */
#define BSF_SYNTHETIC          (1 << 21)

  /* This symbol is an indirect code object.  Unrelated to BSF_INDIRECT.
     The dynamic linker will compute the value of this symbol by
     calling the function that it points to.  BSF_FUNCTION must
     also be also set.  */
#define BSF_GNU_INDIRECT_FUNCTION (1 << 22)
  /* This symbol is a globally unique data object.  The dynamic linker
     will make sure that in the entire process there is just one symbol
     with this name and type in use.  BSF_OBJECT must also be set.  */
#define BSF_GNU_UNIQUE         (1 << 23)

  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 bfd_section *section;

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


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