path: root/include/bfdlink.h

/* bfdlink.h -- header file for BFD link routines
   Copyright (C) 1993-2025 Free Software Foundation, Inc.
   Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support.

   This file is part of BFD, the Binary File Descriptor library.

   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, write to the Free Software
   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#ifndef BFDLINK_H
#define BFDLINK_H

/* Which symbols to strip during a link.  */
enum bfd_link_strip
{
  strip_none,		/* Don't strip any symbols.  */
  strip_debugger,	/* Strip debugging symbols.  */
  strip_some,		/* keep_hash is the list of symbols to keep.  */
  strip_all		/* Strip all symbols.  */
};

/* Which local symbols to discard during a link.  This is irrelevant
   if strip_all is used.  */
enum bfd_link_discard
{
  discard_sec_merge,	/* Discard local temporary symbols in SEC_MERGE
			   sections.  */
  discard_none,		/* Don't discard any locals.  */
  discard_l,		/* Discard local temporary symbols.  */
  discard_all		/* Discard all locals.  */
};

enum notice_asneeded_action {
  notice_as_needed,
  notice_not_needed,
  notice_needed
};

/* Whether to generate ELF common symbols with the STT_COMMON type
   during a relocatable link.  */
enum bfd_link_elf_stt_common
{
  unchanged,
  elf_stt_common,
  no_elf_stt_common
};

/* Describes the type of hash table entry structure being used.
   Different hash table structure have different fields and so
   support different linking features.  */
enum bfd_link_hash_table_type
  {
    bfd_link_generic_hash_table,
    bfd_link_elf_hash_table
  };

/* These are the possible types of an entry in the BFD link hash
   table.  */

enum bfd_link_hash_type
{
  bfd_link_hash_new,		/* Symbol is new.  */
  bfd_link_hash_undefined,	/* Symbol seen before, but undefined.  */
  bfd_link_hash_undefweak,	/* Symbol is weak and undefined.  */
  bfd_link_hash_defined,	/* Symbol is defined.  */
  bfd_link_hash_defweak,	/* Symbol is weak and defined.  */
  bfd_link_hash_common,		/* Symbol is common.  */
  bfd_link_hash_indirect,	/* Symbol is an indirect link.  */
  bfd_link_hash_warning		/* Like indirect, but warn if referenced.  */
};

enum bfd_link_common_skip_ar_symbols
{
  bfd_link_common_skip_none,
  bfd_link_common_skip_text,
  bfd_link_common_skip_data,
  bfd_link_common_skip_all
};

struct bfd_link_hash_common_entry
  {
    unsigned int alignment_power;	/* Alignment.  */
    asection *section;		/* Symbol section.  */
  };

/* The linking routines use a hash table which uses this structure for
   its elements.  */

struct bfd_link_hash_entry
{
  /* Base hash table entry structure.  */
  struct bfd_hash_entry root;

  /* Type of this entry.  */
  ENUM_BITFIELD (bfd_link_hash_type) type : 8;

  /* Symbol is referenced in a normal regular object file,
     as distinct from a LTO IR object file.  */
  unsigned int non_ir_ref_regular : 1;

  /* Symbol is referenced in a normal dynamic object file,
     as distinct from a LTO IR object file.  */
  unsigned int non_ir_ref_dynamic : 1;

  /* The symbol, SYM, is referenced by __real_SYM in an object file.  */
  unsigned int ref_real : 1;

  /* The symbol is a wrapper symbol, __wrap_SYM.  */
  unsigned int wrapper_symbol : 1;

  /* Symbol is a built-in define.  These will be overridden by PROVIDE
     in a linker script.  */
  unsigned int linker_def : 1;

  /* Symbol defined in a linker script.  */
  unsigned int ldscript_def : 1;