82b1edf7b9
should be) anyways.
1623 lines
47 KiB
C
1623 lines
47 KiB
C
/* Intel 80386/80486-specific support for 32-bit ELF
|
||
Copyright 1993 Free Software Foundation, Inc.
|
||
|
||
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 2 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
|
||
|
||
#include "bfd.h"
|
||
#include "sysdep.h"
|
||
#include "bfdlink.h"
|
||
#include "libbfd.h"
|
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#include "libelf.h"
|
||
|
||
static CONST struct reloc_howto_struct *elf_i386_reloc_type_lookup
|
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PARAMS ((bfd *, bfd_reloc_code_real_type));
|
||
static void elf_i386_info_to_howto
|
||
PARAMS ((bfd *, arelent *, Elf32_Internal_Rela *));
|
||
static void elf_i386_info_to_howto_rel
|
||
PARAMS ((bfd *, arelent *, Elf32_Internal_Rel *));
|
||
static boolean elf_i386_create_dynamic_sections
|
||
PARAMS ((bfd *, struct bfd_link_info *));
|
||
static boolean elf_i386_create_got_section
|
||
PARAMS ((bfd *, struct bfd_link_info *));
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||
static boolean elf_i386_check_relocs
|
||
PARAMS ((bfd *, struct bfd_link_info *, asection *,
|
||
const Elf_Internal_Rela *));
|
||
static boolean elf_i386_adjust_dynamic_symbol
|
||
PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
|
||
static boolean elf_i386_size_dynamic_sections
|
||
PARAMS ((bfd *, struct bfd_link_info *));
|
||
static boolean elf_i386_relocate_section
|
||
PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
|
||
Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
|
||
static boolean elf_i386_finish_dynamic_symbol
|
||
PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
|
||
Elf_Internal_Sym *));
|
||
static boolean elf_i386_finish_dynamic_sections
|
||
PARAMS ((bfd *, struct bfd_link_info *));
|
||
|
||
#define USE_REL 1 /* 386 uses REL relocations instead of RELA */
|
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|
||
enum reloc_type
|
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{
|
||
R_386_NONE = 0,
|
||
R_386_32,
|
||
R_386_PC32,
|
||
R_386_GOT32,
|
||
R_386_PLT32,
|
||
R_386_COPY,
|
||
R_386_GLOB_DAT,
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||
R_386_JUMP_SLOT,
|
||
R_386_RELATIVE,
|
||
R_386_GOTOFF,
|
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R_386_GOTPC,
|
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R_386_max
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||
};
|
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|
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#if 0
|
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static CONST char *CONST reloc_type_names[] =
|
||
{
|
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"R_386_NONE",
|
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"R_386_32",
|
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"R_386_PC32",
|
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"R_386_GOT32",
|
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"R_386_PLT32",
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"R_386_COPY",
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"R_386_GLOB_DAT",
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"R_386_JUMP_SLOT",
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"R_386_RELATIVE",
|
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"R_386_GOTOFF",
|
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"R_386_GOTPC",
|
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};
|
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#endif
|
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static reloc_howto_type elf_howto_table[]=
|
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{
|
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HOWTO(R_386_NONE, 0,0, 0,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_NONE", true,0x00000000,0x00000000,false),
|
||
HOWTO(R_386_32, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_32", true,0xffffffff,0xffffffff,false),
|
||
HOWTO(R_386_PC32, 0,2,32,true, 0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_PC32", true,0xffffffff,0xffffffff,true),
|
||
HOWTO(R_386_GOT32, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOT32", true,0xffffffff,0xffffffff,false),
|
||
HOWTO(R_386_PLT32, 0,2,32,true,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_PLT32", true,0xffffffff,0xffffffff,true),
|
||
HOWTO(R_386_COPY, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_COPY", true,0xffffffff,0xffffffff,false),
|
||
HOWTO(R_386_GLOB_DAT, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GLOB_DAT", true,0xffffffff,0xffffffff,false),
|
||
HOWTO(R_386_JUMP_SLOT, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_JUMP_SLOT",true,0xffffffff,0xffffffff,false),
|
||
HOWTO(R_386_RELATIVE, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_RELATIVE", true,0xffffffff,0xffffffff,false),
|
||
HOWTO(R_386_GOTOFF, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOTOFF", true,0xffffffff,0xffffffff,false),
|
||
HOWTO(R_386_GOTPC, 0,2,32,true,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOTPC", true,0xffffffff,0xffffffff,true),
|
||
};
|
||
|
||
#ifdef DEBUG_GEN_RELOC
|
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#define TRACE(str) fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str)
|
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#else
|
||
#define TRACE(str)
|
||
#endif
|
||
|
||
static CONST struct reloc_howto_struct *
|
||
elf_i386_reloc_type_lookup (abfd, code)
|
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bfd *abfd;
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bfd_reloc_code_real_type code;
|
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{
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||
switch (code)
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{
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||
case BFD_RELOC_NONE:
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||
TRACE ("BFD_RELOC_NONE");
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return &elf_howto_table[ (int)R_386_NONE ];
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case BFD_RELOC_32:
|
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TRACE ("BFD_RELOC_32");
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return &elf_howto_table[ (int)R_386_32 ];
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|
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case BFD_RELOC_32_PCREL:
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TRACE ("BFD_RELOC_PC32");
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return &elf_howto_table[ (int)R_386_PC32 ];
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case BFD_RELOC_386_GOT32:
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TRACE ("BFD_RELOC_386_GOT32");
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return &elf_howto_table[ (int)R_386_GOT32 ];
|
||
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||
case BFD_RELOC_386_PLT32:
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TRACE ("BFD_RELOC_386_PLT32");
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return &elf_howto_table[ (int)R_386_PLT32 ];
|
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|
||
case BFD_RELOC_386_COPY:
|
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TRACE ("BFD_RELOC_386_COPY");
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||
return &elf_howto_table[ (int)R_386_COPY ];
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||
|
||
case BFD_RELOC_386_GLOB_DAT:
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||
TRACE ("BFD_RELOC_386_GLOB_DAT");
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return &elf_howto_table[ (int)R_386_GLOB_DAT ];
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||
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||
case BFD_RELOC_386_JUMP_SLOT:
|
||
TRACE ("BFD_RELOC_386_JUMP_SLOT");
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||
return &elf_howto_table[ (int)R_386_JUMP_SLOT ];
|
||
|
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case BFD_RELOC_386_RELATIVE:
|
||
TRACE ("BFD_RELOC_386_RELATIVE");
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||
return &elf_howto_table[ (int)R_386_RELATIVE ];
|
||
|
||
case BFD_RELOC_386_GOTOFF:
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TRACE ("BFD_RELOC_386_GOTOFF");
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return &elf_howto_table[ (int)R_386_GOTOFF ];
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||
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||
case BFD_RELOC_386_GOTPC:
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||
TRACE ("BFD_RELOC_386_GOTPC");
|
||
return &elf_howto_table[ (int)R_386_GOTPC ];
|
||
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||
default:
|
||
break;
|
||
}
|
||
|
||
TRACE ("Unknown");
|
||
return 0;
|
||
}
|
||
|
||
static void
|
||
elf_i386_info_to_howto (abfd, cache_ptr, dst)
|
||
bfd *abfd;
|
||
arelent *cache_ptr;
|
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Elf32_Internal_Rela *dst;
|
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{
|
||
BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_386_max);
|
||
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||
cache_ptr->howto = &elf_howto_table[ELF32_R_TYPE(dst->r_info)];
|
||
}
|
||
|
||
static void
|
||
elf_i386_info_to_howto_rel (abfd, cache_ptr, dst)
|
||
bfd *abfd;
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||
arelent *cache_ptr;
|
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Elf32_Internal_Rel *dst;
|
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{
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BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_386_max);
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cache_ptr->howto = &elf_howto_table[ELF32_R_TYPE(dst->r_info)];
|
||
}
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||
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||
/* Functions for the i386 ELF linker. */
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||
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||
/* The name of the dynamic interpreter. This is put in the .interp
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section. */
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#define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
|
||
|
||
/* The size in bytes of an entry in the procedure linkage table. */
|
||
|
||
#define PLT_ENTRY_SIZE 16
|
||
|
||
/* The first entry in an absolute procedure linkage table looks like
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||
this. See the SVR4 ABI i386 supplement to see how this works. */
|
||
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||
static bfd_byte elf_i386_plt0_entry[PLT_ENTRY_SIZE] =
|
||
{
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||
0xff, 0x35, /* pushl contents of address */
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0, 0, 0, 0, /* replaced with address of .got + 4. */
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0xff, 0x25, /* jmp indirect */
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||
0, 0, 0, 0, /* replaced with address of .got + 8. */
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||
0, 0, 0, 0 /* pad out to 16 bytes. */
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||
};
|
||
|
||
/* Subsequent entries in an absolute procedure linkage table look like
|
||
this. */
|
||
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static bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
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{
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0xff, 0x25, /* jmp indirect */
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||
0, 0, 0, 0, /* replaced with address of this symbol in .got. */
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||
0x68, /* pushl immediate */
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||
0, 0, 0, 0, /* replaced with offset into relocation table. */
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||
0xe9, /* jmp relative */
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0, 0, 0, 0 /* replaced with offset to start of .plt. */
|
||
};
|
||
|
||
/* The first entry in a PIC procedure linkage table look like this. */
|
||
|
||
static bfd_byte elf_i386_pic_plt0_entry[PLT_ENTRY_SIZE] =
|
||
{
|
||
0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */
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||
0xff, 0xa3, 8, 0, 0, 0, /* jmp *8(%ebx) */
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||
0, 0, 0, 0 /* pad out to 16 bytes. */
|
||
};
|
||
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||
/* Subsequent entries in a PIC procedure linkage table look like this. */
|
||
|
||
static bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] =
|
||
{
|
||
0xff, 0xa3, /* jmp *offset(%ebx) */
|
||
0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
|
||
0x68, /* pushl immediate */
|
||
0, 0, 0, 0, /* replaced with offset into relocation table. */
|
||
0xe9, /* jmp relative */
|
||
0, 0, 0, 0 /* replaced with offset to start of .plt. */
|
||
};
|
||
|
||
/* Create dynamic sections when linking against a dynamic object. */
|
||
|
||
static boolean
|
||
elf_i386_create_dynamic_sections (abfd, info)
|
||
bfd *abfd;
|
||
struct bfd_link_info *info;
|
||
{
|
||
flagword flags;
|
||
register asection *s;
|
||
|
||
/* We need to create .plt, .rel.plt, .got, .got.plt, .dynbss, and
|
||
.rel.bss sections. */
|
||
|
||
flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
|
||
|
||
s = bfd_make_section (abfd, ".plt");
|
||
if (s == NULL
|
||
|| ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY | SEC_CODE)
|
||
|| ! bfd_set_section_alignment (abfd, s, 2))
|
||
return false;
|
||
|
||
s = bfd_make_section (abfd, ".rel.plt");
|
||
if (s == NULL
|
||
|| ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
|
||
|| ! bfd_set_section_alignment (abfd, s, 2))
|
||
return false;
|
||
|
||
if (! elf_i386_create_got_section (abfd, info))
|
||
return false;
|
||
|
||
/* The .dynbss section is a place to put symbols which are defined
|
||
by dynamic objects, are referenced by regular objects, and are
|
||
not functions. We must allocate space for them in the process
|
||
image and use a R_386_COPY reloc to tell the dynamic linker to
|
||
initialize them at run time. The linker script puts the .dynbss
|
||
section into the .bss section of the final image. */
|
||
s = bfd_make_section (abfd, ".dynbss");
|
||
if (s == NULL
|
||
|| ! bfd_set_section_flags (abfd, s, SEC_ALLOC))
|
||
return false;
|
||
|
||
/* The .rel.bss section holds copy relocs. This section is not
|
||
normally needed. We need to create it here, though, so that the
|
||
linker will map it to an output section. We can't just create it
|
||
only if we need it, because we will not know whether we need it
|
||
until we have seen all the input files, and the first time the
|
||
main linker code calls BFD after examining all the input files
|
||
(size_dynamic_sections) the input sections have already been
|
||
mapped to the output sections. If the section turns out not to
|
||
be needed, we can discard it later. We will never need this
|
||
section when generating a shared object, since they do not use
|
||
copy relocs. */
|
||
if (! info->shared)
|
||
{
|
||
s = bfd_make_section (abfd, ".rel.bss");
|
||
if (s == NULL
|
||
|| ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
|
||
|| ! bfd_set_section_alignment (abfd, s, 2))
|
||
return false;
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Create the .got section to hold the global offset table, and the
|
||
.got.plt section to hold procedure linkage table GOT entries. The
|
||
linker script will put .got.plt into the output .got section. */
|
||
|
||
static boolean
|
||
elf_i386_create_got_section (abfd, info)
|
||
bfd *abfd;
|
||
struct bfd_link_info *info;
|
||
{
|
||
flagword flags;
|
||
register asection *s;
|
||
struct elf_link_hash_entry *h;
|
||
|
||
/* This function may be called more than once. */
|
||
if (bfd_get_section_by_name (abfd, ".got") != NULL)
|
||
return true;
|
||
|
||
flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
|
||
|
||
s = bfd_make_section (abfd, ".got");
|
||
if (s == NULL
|
||
|| ! bfd_set_section_flags (abfd, s, flags)
|
||
|| ! bfd_set_section_alignment (abfd, s, 2))
|
||
return false;
|
||
|
||
s = bfd_make_section (abfd, ".got.plt");
|
||
if (s == NULL
|
||
|| ! bfd_set_section_flags (abfd, s, flags)
|
||
|| ! bfd_set_section_alignment (abfd, s, 2))
|
||
return false;
|
||
|
||
/* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the
|
||
.got.plt section, which will be placed at the start of the output
|
||
.got section. We don't do this in the linker script because we
|
||
don't want to define the symbol if we are not creating a global
|
||
offset table. */
|
||
h = NULL;
|
||
if (! (_bfd_generic_link_add_one_symbol
|
||
(info, abfd, "_GLOBAL_OFFSET_TABLE_", BSF_GLOBAL, s, (bfd_vma) 0,
|
||
(const char *) NULL, false, get_elf_backend_data (abfd)->collect,
|
||
(struct bfd_link_hash_entry **) &h)))
|
||
return false;
|
||
h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
|
||
h->type = STT_OBJECT;
|
||
|
||
if (info->shared
|
||
&& ! bfd_elf32_link_record_dynamic_symbol (info, h))
|
||
return false;
|
||
|
||
/* The first three global offset table entries are reserved. */
|
||
s->_raw_size += 3 * 4;
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Look through the relocs for a section during the first phase, and
|
||
allocate space in the global offset table or procedure linkage
|
||
table. */
|
||
|
||
static boolean
|
||
elf_i386_check_relocs (abfd, info, sec, relocs)
|
||
bfd *abfd;
|
||
struct bfd_link_info *info;
|
||
asection *sec;
|
||
const Elf_Internal_Rela *relocs;
|
||
{
|
||
bfd *dynobj;
|
||
Elf_Internal_Shdr *symtab_hdr;
|
||
struct elf_link_hash_entry **sym_hashes;
|
||
bfd_vma *local_got_offsets;
|
||
const Elf_Internal_Rela *rel;
|
||
const Elf_Internal_Rela *rel_end;
|
||
asection *sgot;
|
||
asection *srelgot;
|
||
asection *sreloc;
|
||
|
||
if (info->relocateable)
|
||
return true;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
|
||
sym_hashes = elf_sym_hashes (abfd);
|
||
local_got_offsets = elf_local_got_offsets (abfd);
|
||
|
||
sgot = NULL;
|
||
srelgot = NULL;
|
||
sreloc = NULL;
|
||
|
||
rel_end = relocs + sec->reloc_count;
|
||
for (rel = relocs; rel < rel_end; rel++)
|
||
{
|
||
long r_symndx;
|
||
struct elf_link_hash_entry *h;
|
||
|
||
r_symndx = ELF32_R_SYM (rel->r_info);
|
||
|
||
if (r_symndx < symtab_hdr->sh_info)
|
||
h = NULL;
|
||
else
|
||
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
|
||
|
||
/* Some relocs require a global offset table. */
|
||
if (dynobj == NULL)
|
||
{
|
||
switch (ELF32_R_TYPE (rel->r_info))
|
||
{
|
||
case R_386_GOT32:
|
||
case R_386_GOTOFF:
|
||
case R_386_GOTPC:
|
||
elf_hash_table (info)->dynobj = dynobj = abfd;
|
||
if (! elf_i386_create_got_section (dynobj, info))
|
||
return false;
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
}
|
||
|
||
switch (ELF32_R_TYPE (rel->r_info))
|
||
{
|
||
case R_386_GOT32:
|
||
/* This symbol requires a global offset table entry. */
|
||
|
||
if (sgot == NULL)
|
||
{
|
||
sgot = bfd_get_section_by_name (dynobj, ".got");
|
||
BFD_ASSERT (sgot != NULL);
|
||
}
|
||
|
||
if (srelgot == NULL
|
||
&& (h != NULL || info->shared))
|
||
{
|
||
srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
|
||
if (srelgot == NULL)
|
||
{
|
||
srelgot = bfd_make_section (dynobj, ".rel.got");
|
||
if (srelgot == NULL
|
||
|| ! bfd_set_section_flags (dynobj, srelgot,
|
||
(SEC_ALLOC
|
||
| SEC_LOAD
|
||
| SEC_HAS_CONTENTS
|
||
| SEC_IN_MEMORY
|
||
| SEC_READONLY))
|
||
|| ! bfd_set_section_alignment (dynobj, srelgot, 2))
|
||
return false;
|
||
}
|
||
}
|
||
|
||
if (h != NULL)
|
||
{
|
||
if (h->got_offset != (bfd_vma) -1)
|
||
{
|
||
/* We have already allocated space in the .got. */
|
||
break;
|
||
}
|
||
h->got_offset = sgot->_raw_size;
|
||
|
||
/* Make sure this symbol is output as a dynamic symbol. */
|
||
if (h->dynindx == -1)
|
||
{
|
||
if (! bfd_elf32_link_record_dynamic_symbol (info, h))
|
||
return false;
|
||
}
|
||
|
||
srelgot->_raw_size += sizeof (Elf32_External_Rel);
|
||
}
|
||
else
|
||
{
|
||
/* This is a global offset table entry for a local
|
||
symbol. */
|
||
if (local_got_offsets == NULL)
|
||
{
|
||
size_t size;
|
||
register int i;
|
||
|
||
size = symtab_hdr->sh_info * sizeof (bfd_vma);
|
||
local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size);
|
||
if (local_got_offsets == NULL)
|
||
{
|
||
bfd_set_error (bfd_error_no_memory);
|
||
return false;
|
||
}
|
||
elf_local_got_offsets (abfd) = local_got_offsets;
|
||
for (i = 0; i < symtab_hdr->sh_info; i++)
|
||
local_got_offsets[i] = (bfd_vma) -1;
|
||
}
|
||
if (local_got_offsets[r_symndx] != (bfd_vma) -1)
|
||
{
|
||
/* We have already allocated space in the .got. */
|
||
break;
|
||
}
|
||
local_got_offsets[r_symndx] = sgot->_raw_size;
|
||
|
||
if (info->shared)
|
||
{
|
||
/* If we are generating a shared object, we need to
|
||
output a R_386_RELATIVE reloc so that the dynamic
|
||
linker can adjust this GOT entry. */
|
||
srelgot->_raw_size += sizeof (Elf32_External_Rel);
|
||
}
|
||
}
|
||
|
||
sgot->_raw_size += 4;
|
||
|
||
break;
|
||
|
||
case R_386_PLT32:
|
||
/* This symbol requires a procedure linkage table entry. We
|
||
actually build the entry in adjust_dynamic_symbol,
|
||
because this might be a case of linking PIC code without
|
||
linking in any dynamic objects, in which case we don't
|
||
need to generate a procedure linkage table after all. */
|
||
|
||
/* If this is a local symbol, we resolve it directly without
|
||
creating a procedure linkage table entry. */
|
||
if (h == NULL)
|
||
continue;
|
||
|
||
/* Make sure this symbol is output as a dynamic symbol. */
|
||
if (h->dynindx == -1)
|
||
{
|
||
if (! bfd_elf32_link_record_dynamic_symbol (info, h))
|
||
return false;
|
||
}
|
||
|
||
h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
|
||
|
||
break;
|
||
|
||
case R_386_32:
|
||
case R_386_PC32:
|
||
if (info->shared
|
||
&& (sec->flags & SEC_ALLOC) != 0)
|
||
{
|
||
/* When creating a shared object, we must copy these
|
||
reloc types into the output file. We create a reloc
|
||
section in dynobj and make room for this reloc. */
|
||
if (sreloc == NULL)
|
||
{
|
||
const char *name;
|
||
|
||
name = (elf_string_from_elf_section
|
||
(abfd,
|
||
elf_elfheader (abfd)->e_shstrndx,
|
||
elf_section_data (sec)->rel_hdr.sh_name));
|
||
if (name == NULL)
|
||
return false;
|
||
|
||
BFD_ASSERT (strncmp (name, ".rel", 4) == 0
|
||
&& strcmp (bfd_get_section_name (abfd, sec),
|
||
name + 4) == 0);
|
||
|
||
sreloc = bfd_get_section_by_name (dynobj, name);
|
||
if (sreloc == NULL)
|
||
{
|
||
sreloc = bfd_make_section (dynobj, name);
|
||
if (sreloc == NULL
|
||
|| ! bfd_set_section_flags (dynobj, sreloc,
|
||
(SEC_ALLOC
|
||
| SEC_LOAD
|
||
| SEC_HAS_CONTENTS
|
||
| SEC_IN_MEMORY
|
||
| SEC_READONLY))
|
||
|| ! bfd_set_section_alignment (dynobj, sreloc, 2))
|
||
return false;
|
||
}
|
||
}
|
||
|
||
sreloc->_raw_size += sizeof (Elf32_External_Rel);
|
||
}
|
||
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Adjust a symbol defined by a dynamic object and referenced by a
|
||
regular object. The current definition is in some section of the
|
||
dynamic object, but we're not including those sections. We have to
|
||
change the definition to something the rest of the link can
|
||
understand. */
|
||
|
||
static boolean
|
||
elf_i386_adjust_dynamic_symbol (info, h)
|
||
struct bfd_link_info *info;
|
||
struct elf_link_hash_entry *h;
|
||
{
|
||
bfd *dynobj;
|
||
asection *s;
|
||
unsigned int power_of_two;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
|
||
/* Make sure we know what is going on here. */
|
||
BFD_ASSERT (dynobj != NULL
|
||
&& ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
|
||
|| ((h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_DYNAMIC) != 0
|
||
&& (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_REF_REGULAR) != 0
|
||
&& (h->elf_link_hash_flags
|
||
& ELF_LINK_HASH_DEF_REGULAR) == 0
|
||
&& (elf_elfheader (h->root.u.def.section->owner)->e_type
|
||
== ET_DYN)
|
||
&& h->root.type == bfd_link_hash_defined
|
||
&& (bfd_get_flavour (h->root.u.def.section->owner)
|
||
== bfd_target_elf_flavour)
|
||
&& h->root.u.def.section->output_section == NULL)));
|
||
|
||
/* If this is a function, put it in the procedure linkage table. We
|
||
will fill in the contents of the procedure linkage table later,
|
||
when we know the address of the .got section. */
|
||
if (h->type == STT_FUNC
|
||
|| (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
|
||
{
|
||
if (! elf_hash_table (info)->dynamic_sections_created)
|
||
{
|
||
/* This case can occur if we saw a PLT32 reloc in an input
|
||
file, but none of the input files were dynamic objects.
|
||
In such a case, we don't actually need to build a
|
||
procedure linkage table, and we can just do a PC32 reloc
|
||
instead. */
|
||
BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
|
||
return true;
|
||
}
|
||
|
||
s = bfd_get_section_by_name (dynobj, ".plt");
|
||
BFD_ASSERT (s != NULL);
|
||
|
||
/* If this is the first .plt entry, make room for the special
|
||
first entry. */
|
||
if (s->_raw_size == 0)
|
||
s->_raw_size += PLT_ENTRY_SIZE;
|
||
|
||
/* If this symbol is not defined in a regular file, and we are
|
||
not generating a shared library, then set the symbol to this
|
||
location in the .plt. This is required to make function
|
||
pointers compare as equal between the normal executable and
|
||
the shared library. */
|
||
if (! info->shared
|
||
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
|
||
{
|
||
h->root.u.def.section = s;
|
||
h->root.u.def.value = s->_raw_size;
|
||
}
|
||
|
||
h->plt_offset = s->_raw_size;
|
||
|
||
/* Make room for this entry. */
|
||
s->_raw_size += PLT_ENTRY_SIZE;
|
||
|
||
/* We also need to make an entry in the .got.plt section, which
|
||
will be placed in the .got section by the linker script. */
|
||
|
||
s = bfd_get_section_by_name (dynobj, ".got.plt");
|
||
BFD_ASSERT (s != NULL);
|
||
s->_raw_size += 4;
|
||
|
||
/* We also need to make an entry in the .rel.plt section. */
|
||
|
||
s = bfd_get_section_by_name (dynobj, ".rel.plt");
|
||
BFD_ASSERT (s != NULL);
|
||
s->_raw_size += sizeof (Elf32_External_Rel);
|
||
|
||
return true;
|
||
}
|
||
|
||
/* If this is a weak symbol, and there is a real definition, the
|
||
processor independent code will have arranged for us to see the
|
||
real definition first, and we can just use the same value. */
|
||
if (h->weakdef != NULL)
|
||
{
|
||
BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined);
|
||
h->root.u.def.section = h->weakdef->root.u.def.section;
|
||
h->root.u.def.value = h->weakdef->root.u.def.value;
|
||
return true;
|
||
}
|
||
|
||
/* This is a reference to a symbol defined by a dynamic object which
|
||
is not a function. */
|
||
|
||
/* If we are creating a shared library, we must presume that the
|
||
only references to the symbol are via the global offset table.
|
||
For such cases we need not do anything here; the relocations will
|
||
be handled correctly by relocate_section. */
|
||
if (info->shared)
|
||
return true;
|
||
|
||
/* We must allocate the symbol in our .dynbss section, which will
|
||
become part of the .bss section of the executable. There will be
|
||
an entry for this symbol in the .dynsym section. The dynamic
|
||
object will contain position independent code, so all references
|
||
from the dynamic object to this symbol will go through the global
|
||
offset table. The dynamic linker will use the .dynsym entry to
|
||
determine the address it must put in the global offset table, so
|
||
both the dynamic object and the regular object will refer to the
|
||
same memory location for the variable. */
|
||
|
||
s = bfd_get_section_by_name (dynobj, ".dynbss");
|
||
BFD_ASSERT (s != NULL);
|
||
|
||
/* If the symbol is currently defined in the .bss section of the
|
||
dynamic object, then it is OK to simply initialize it to zero.
|
||
If the symbol is in some other section, we must generate a
|
||
R_386_COPY reloc to tell the dynamic linker to copy the initial
|
||
value out of the dynamic object and into the runtime process
|
||
image. We need to remember the offset into the .rel.bss section
|
||
we are going to use. */
|
||
if ((h->root.u.def.section->flags & SEC_LOAD) != 0)
|
||
{
|
||
asection *srel;
|
||
|
||
srel = bfd_get_section_by_name (dynobj, ".rel.bss");
|
||
BFD_ASSERT (srel != NULL);
|
||
srel->_raw_size += sizeof (Elf32_External_Rel);
|
||
h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
|
||
}
|
||
|
||
/* We need to figure out the alignment required for this symbol. I
|
||
have no idea how ELF linkers handle this. */
|
||
power_of_two = bfd_log2 (h->size);
|
||
if (power_of_two > 3)
|
||
power_of_two = 3;
|
||
|
||
/* Apply the required alignment. */
|
||
s->_raw_size = BFD_ALIGN (s->_raw_size,
|
||
(bfd_size_type) (1 << power_of_two));
|
||
if (power_of_two > bfd_get_section_alignment (dynobj, s))
|
||
{
|
||
if (! bfd_set_section_alignment (dynobj, s, power_of_two))
|
||
return false;
|
||
}
|
||
|
||
/* Define the symbol as being at this point in the section. */
|
||
h->root.u.def.section = s;
|
||
h->root.u.def.value = s->_raw_size;
|
||
|
||
/* Increment the section size to make room for the symbol. */
|
||
s->_raw_size += h->size;
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Set the sizes of the dynamic sections. */
|
||
|
||
static boolean
|
||
elf_i386_size_dynamic_sections (output_bfd, info)
|
||
bfd *output_bfd;
|
||
struct bfd_link_info *info;
|
||
{
|
||
bfd *dynobj;
|
||
asection *s;
|
||
boolean plt;
|
||
boolean relocs;
|
||
boolean reltext;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
BFD_ASSERT (dynobj != NULL);
|
||
|
||
if (elf_hash_table (info)->dynamic_sections_created)
|
||
{
|
||
/* Set the contents of the .interp section to the interpreter. */
|
||
if (! info->shared)
|
||
{
|
||
s = bfd_get_section_by_name (dynobj, ".interp");
|
||
BFD_ASSERT (s != NULL);
|
||
s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
|
||
s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* We may have created entries in the .rel.got section.
|
||
However, if we are not creating the dynamic sections, we will
|
||
not actually use these entries. Reset the size of .rel.got,
|
||
which will cause it to get stripped from the output file
|
||
below. */
|
||
s = bfd_get_section_by_name (dynobj, ".rel.got");
|
||
if (s != NULL)
|
||
s->_raw_size = 0;
|
||
}
|
||
|
||
/* The check_relocs and adjust_dynamic_symbol entry points have
|
||
determined the sizes of the various dynamic sections. Allocate
|
||
memory for them. */
|
||
plt = false;
|
||
relocs = false;
|
||
reltext = false;
|
||
for (s = dynobj->sections; s != NULL; s = s->next)
|
||
{
|
||
const char *name;
|
||
boolean strip;
|
||
|
||
if ((s->flags & SEC_IN_MEMORY) == 0)
|
||
continue;
|
||
|
||
/* It's OK to base decisions on the section name, because none
|
||
of the dynobj section names depend upon the input files. */
|
||
name = bfd_get_section_name (dynobj, s);
|
||
|
||
strip = false;
|
||
|
||
if (strcmp (name, ".plt") == 0)
|
||
{
|
||
if (s->_raw_size == 0)
|
||
{
|
||
/* Strip this section if we don't need it; see the
|
||
comment below. */
|
||
strip = true;
|
||
}
|
||
else
|
||
{
|
||
/* Remember whether there is a PLT. */
|
||
plt = true;
|
||
}
|
||
}
|
||
else if (strncmp (name, ".rel", 4) == 0)
|
||
{
|
||
if (s->_raw_size == 0)
|
||
{
|
||
/* If we don't need this section, strip it from the
|
||
output file. This is mostly to handle .rel.bss and
|
||
.rel.plt. We must create both sections in
|
||
create_dynamic_sections, because they must be created
|
||
before the linker maps input sections to output
|
||
sections. The linker does that before
|
||
adjust_dynamic_symbol is called, and it is that
|
||
function which decides whether anything needs to go
|
||
into these sections. */
|
||
strip = true;
|
||
}
|
||
else
|
||
{
|
||
asection *target;
|
||
|
||
/* Remember whether there are any reloc sections other
|
||
than .rel.plt. */
|
||
if (strcmp (name, ".rel.plt") != 0)
|
||
relocs = true;
|
||
|
||
/* If this relocation section applies to a read only
|
||
section, then we probably need a DT_TEXTREL entry. */
|
||
target = bfd_get_section_by_name (output_bfd, name + 4);
|
||
if (target != NULL
|
||
&& (target->flags & SEC_READONLY) != 0)
|
||
reltext = true;
|
||
|
||
/* We use the reloc_count field as a counter if we need
|
||
to copy relocs into the output file. */
|
||
s->reloc_count = 0;
|
||
}
|
||
}
|
||
else if (strncmp (name, ".got", 4) != 0)
|
||
{
|
||
/* It's not one of our sections, so don't allocate space. */
|
||
continue;
|
||
}
|
||
|
||
if (strip)
|
||
{
|
||
asection **spp;
|
||
|
||
for (spp = &s->output_section->owner->sections;
|
||
*spp != s->output_section;
|
||
spp = &(*spp)->next)
|
||
;
|
||
*spp = s->output_section->next;
|
||
--s->output_section->owner->section_count;
|
||
|
||
continue;
|
||
}
|
||
|
||
/* Allocate memory for the section contents. */
|
||
s->contents = (bfd_byte *) bfd_alloc (dynobj, s->_raw_size);
|
||
if (s->contents == NULL && s->_raw_size != 0)
|
||
{
|
||
bfd_set_error (bfd_error_no_memory);
|
||
return false;
|
||
}
|
||
}
|
||
|
||
if (elf_hash_table (info)->dynamic_sections_created)
|
||
{
|
||
/* Add some entries to the .dynamic section. We fill in the
|
||
values later, in elf_i386_finish_dynamic_sections, but we
|
||
must add the entries now so that we get the correct size for
|
||
the .dynamic section. The DT_DEBUG entry is filled in by the
|
||
dynamic linker and used by the debugger. */
|
||
if (! info->shared)
|
||
{
|
||
if (! bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0))
|
||
return false;
|
||
}
|
||
|
||
if (plt)
|
||
{
|
||
if (! bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0)
|
||
|| ! bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0)
|
||
|| ! bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_REL)
|
||
|| ! bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0))
|
||
return false;
|
||
}
|
||
|
||
if (relocs)
|
||
{
|
||
if (! bfd_elf32_add_dynamic_entry (info, DT_REL, 0)
|
||
|| ! bfd_elf32_add_dynamic_entry (info, DT_RELSZ, 0)
|
||
|| ! bfd_elf32_add_dynamic_entry (info, DT_RELENT,
|
||
sizeof (Elf32_External_Rel)))
|
||
return false;
|
||
}
|
||
|
||
if (reltext)
|
||
{
|
||
if (! bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0))
|
||
return false;
|
||
}
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Relocate an i386 ELF section. */
|
||
|
||
static boolean
|
||
elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
|
||
contents, relocs, local_syms, local_sections)
|
||
bfd *output_bfd;
|
||
struct bfd_link_info *info;
|
||
bfd *input_bfd;
|
||
asection *input_section;
|
||
bfd_byte *contents;
|
||
Elf_Internal_Rela *relocs;
|
||
Elf_Internal_Sym *local_syms;
|
||
asection **local_sections;
|
||
{
|
||
bfd *dynobj;
|
||
Elf_Internal_Shdr *symtab_hdr;
|
||
struct elf_link_hash_entry **sym_hashes;
|
||
bfd_vma *local_got_offsets;
|
||
asection *sgot;
|
||
asection *splt;
|
||
asection *sreloc;
|
||
Elf_Internal_Rela *rel;
|
||
Elf_Internal_Rela *relend;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
|
||
sym_hashes = elf_sym_hashes (input_bfd);
|
||
local_got_offsets = elf_local_got_offsets (input_bfd);
|
||
|
||
sgot = NULL;
|
||
splt = NULL;
|
||
sreloc = NULL;
|
||
|
||
rel = relocs;
|
||
relend = relocs + input_section->reloc_count;
|
||
for (; rel < relend; rel++)
|
||
{
|
||
int r_type;
|
||
reloc_howto_type *howto;
|
||
long r_symndx;
|
||
struct elf_link_hash_entry *h;
|
||
Elf_Internal_Sym *sym;
|
||
asection *sec;
|
||
bfd_vma relocation;
|
||
bfd_reloc_status_type r;
|
||
|
||
r_type = ELF32_R_TYPE (rel->r_info);
|
||
if (r_type < 0 || r_type >= (int) R_386_max)
|
||
{
|
||
bfd_set_error (bfd_error_bad_value);
|
||
return false;
|
||
}
|
||
howto = elf_howto_table + r_type;
|
||
|
||
r_symndx = ELF32_R_SYM (rel->r_info);
|
||
|
||
if (info->relocateable)
|
||
{
|
||
/* This is a relocateable link. We don't have to change
|
||
anything, unless the reloc is against a section symbol,
|
||
in which case we have to adjust according to where the
|
||
section symbol winds up in the output section. */
|
||
if (r_symndx < symtab_hdr->sh_info)
|
||
{
|
||
sym = local_syms + r_symndx;
|
||
if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
|
||
{
|
||
bfd_vma val;
|
||
|
||
sec = local_sections[r_symndx];
|
||
val = bfd_get_32 (input_bfd, contents + rel->r_offset);
|
||
val += sec->output_offset + sym->st_value;
|
||
bfd_put_32 (input_bfd, val, contents + rel->r_offset);
|
||
}
|
||
}
|
||
|
||
continue;
|
||
}
|
||
|
||
/* This is a final link. */
|
||
h = NULL;
|
||
sym = NULL;
|
||
sec = NULL;
|
||
if (r_symndx < symtab_hdr->sh_info)
|
||
{
|
||
sym = local_syms + r_symndx;
|
||
sec = local_sections[r_symndx];
|
||
relocation = (sec->output_section->vma
|
||
+ sec->output_offset
|
||
+ sym->st_value);
|
||
}
|
||
else
|
||
{
|
||
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
|
||
if (h->root.type == bfd_link_hash_defined)
|
||
{
|
||
sec = h->root.u.def.section;
|
||
if (r_type == R_386_GOTPC
|
||
|| (r_type == R_386_PLT32
|
||
&& h->plt_offset != (bfd_vma) -1)
|
||
|| (r_type == R_386_GOT32
|
||
&& elf_hash_table (info)->dynamic_sections_created)
|
||
|| (info->shared
|
||
&& (r_type == R_386_32
|
||
|| r_type == R_386_PC32)
|
||
&& (input_section->flags & SEC_ALLOC) != 0))
|
||
{
|
||
/* In these cases, we don't need the relocation
|
||
value. We check specially because in some
|
||
obscure cases sec->output_section will be NULL. */
|
||
relocation = 0;
|
||
}
|
||
else
|
||
relocation = (h->root.u.def.value
|
||
+ sec->output_section->vma
|
||
+ sec->output_offset);
|
||
}
|
||
else if (h->root.type == bfd_link_hash_weak)
|
||
relocation = 0;
|
||
else if (info->shared)
|
||
relocation = 0;
|
||
else
|
||
{
|
||
if (! ((*info->callbacks->undefined_symbol)
|
||
(info, h->root.root.string, input_bfd,
|
||
input_section, rel->r_offset)))
|
||
return false;
|
||
relocation = 0;
|
||
}
|
||
}
|
||
|
||
switch (r_type)
|
||
{
|
||
case R_386_GOT32:
|
||
/* Relocation is to the entry for this symbol in the global
|
||
offset table. */
|
||
if (sgot == NULL)
|
||
{
|
||
sgot = bfd_get_section_by_name (dynobj, ".got");
|
||
BFD_ASSERT (sgot != NULL);
|
||
}
|
||
|
||
if (h != NULL)
|
||
{
|
||
bfd_vma off;
|
||
|
||
off = h->got_offset;
|
||
BFD_ASSERT (off != (bfd_vma) -1);
|
||
|
||
if (! elf_hash_table (info)->dynamic_sections_created)
|
||
{
|
||
/* This is actually a static link. We must
|
||
initialize this entry in the global offset table.
|
||
Since the offset must always be a multiple of 4,
|
||
we use the least significant bit to record
|
||
whether we have initialized it already.
|
||
|
||
When doing a dynamic link, we create a .rel.got
|
||
relocation entry to initialize the value. This
|
||
is done in the finish_dynamic_symbol routine. */
|
||
if ((off & 1) != 0)
|
||
off &= ~1;
|
||
else
|
||
{
|
||
bfd_put_32 (output_bfd, relocation,
|
||
sgot->contents + off);
|
||
h->got_offset |= 1;
|
||
}
|
||
}
|
||
|
||
relocation = sgot->output_offset + off;
|
||
}
|
||
else
|
||
{
|
||
bfd_vma off;
|
||
|
||
BFD_ASSERT (local_got_offsets != NULL
|
||
&& local_got_offsets[r_symndx] != (bfd_vma) -1);
|
||
|
||
off = local_got_offsets[r_symndx];
|
||
|
||
/* The offset must always be a multiple of 4. We use
|
||
the least significant bit to record whether we have
|
||
already generated the necessary reloc. */
|
||
if ((off & 1) != 0)
|
||
off &= ~1;
|
||
else
|
||
{
|
||
bfd_put_32 (output_bfd, relocation, sgot->contents + off);
|
||
|
||
if (info->shared)
|
||
{
|
||
asection *srelgot;
|
||
Elf_Internal_Rel outrel;
|
||
|
||
srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
|
||
BFD_ASSERT (srelgot != NULL);
|
||
|
||
outrel.r_offset = (sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ off);
|
||
outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
|
||
bfd_elf32_swap_reloc_out (output_bfd, &outrel,
|
||
(((Elf32_External_Rel *)
|
||
srelgot->contents)
|
||
+ srelgot->reloc_count));
|
||
++srelgot->reloc_count;
|
||
}
|
||
|
||
local_got_offsets[r_symndx] |= 1;
|
||
}
|
||
|
||
relocation = sgot->output_offset + off;
|
||
}
|
||
|
||
break;
|
||
|
||
case R_386_GOTOFF:
|
||
/* Relocation is relative to the start of the global offset
|
||
table. */
|
||
|
||
if (sgot == NULL)
|
||
{
|
||
sgot = bfd_get_section_by_name (dynobj, ".got");
|
||
BFD_ASSERT (sgot != NULL);
|
||
}
|
||
|
||
/* Note that sgot->output_offset is not involved in this
|
||
calculation. We always want the start of .got. If we
|
||
defined _GLOBAL_OFFSET_TABLE in a different way, as is
|
||
permitted by the ABI, we might have to change this
|
||
calculation. */
|
||
relocation -= sgot->output_section->vma;
|
||
|
||
break;
|
||
|
||
case R_386_GOTPC:
|
||
/* Use global offset table as symbol value. */
|
||
|
||
if (sgot == NULL)
|
||
{
|
||
sgot = bfd_get_section_by_name (dynobj, ".got");
|
||
BFD_ASSERT (sgot != NULL);
|
||
}
|
||
|
||
relocation = sgot->output_section->vma;
|
||
|
||
break;
|
||
|
||
case R_386_PLT32:
|
||
/* Relocation is to the entry for this symbol in the
|
||
procedure linkage table. */
|
||
|
||
/* Resolve a PLT32 reloc again a local symbol directly,
|
||
without using the procedure linkage table. */
|
||
if (h == NULL)
|
||
break;
|
||
|
||
if (h->plt_offset == (bfd_vma) -1)
|
||
{
|
||
/* We didn't make a PLT entry for this symbol. This
|
||
happens when statically linking PIC code. */
|
||
break;
|
||
}
|
||
|
||
if (splt == NULL)
|
||
{
|
||
splt = bfd_get_section_by_name (dynobj, ".plt");
|
||
BFD_ASSERT (splt != NULL);
|
||
}
|
||
|
||
relocation = (splt->output_section->vma
|
||
+ splt->output_offset
|
||
+ h->plt_offset);
|
||
|
||
break;
|
||
|
||
case R_386_32:
|
||
case R_386_PC32:
|
||
if (info->shared
|
||
&& (input_section->flags & SEC_ALLOC) != 0)
|
||
{
|
||
Elf_Internal_Rel outrel;
|
||
|
||
/* When generating a shared object, these relocations
|
||
are copied into the output file to be resolved at run
|
||
time. */
|
||
|
||
if (sreloc == NULL)
|
||
{
|
||
const char *name;
|
||
|
||
name = (elf_string_from_elf_section
|
||
(input_bfd,
|
||
elf_elfheader (input_bfd)->e_shstrndx,
|
||
elf_section_data (input_section)->rel_hdr.sh_name));
|
||
if (name == NULL)
|
||
return false;
|
||
|
||
BFD_ASSERT (strncmp (name, ".rel", 4) == 0
|
||
&& strcmp (bfd_get_section_name (input_bfd,
|
||
input_section),
|
||
name + 4) == 0);
|
||
|
||
sreloc = bfd_get_section_by_name (dynobj, name);
|
||
BFD_ASSERT (sreloc != NULL);
|
||
}
|
||
|
||
outrel.r_offset = (rel->r_offset
|
||
+ input_section->output_section->vma
|
||
+ input_section->output_offset);
|
||
if (r_type == R_386_PC32)
|
||
{
|
||
BFD_ASSERT (h != NULL && h->dynindx != -1);
|
||
outrel.r_info = ELF32_R_INFO (h->dynindx, R_386_PC32);
|
||
}
|
||
else
|
||
{
|
||
if (h == NULL)
|
||
outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
|
||
else
|
||
{
|
||
BFD_ASSERT (h->dynindx != (bfd_vma) -1);
|
||
outrel.r_info = ELF32_R_INFO (h->dynindx, R_386_32);
|
||
}
|
||
}
|
||
|
||
bfd_elf32_swap_reloc_out (output_bfd, &outrel,
|
||
(((Elf32_External_Rel *)
|
||
sreloc->contents)
|
||
+ sreloc->reloc_count));
|
||
++sreloc->reloc_count;
|
||
|
||
/* If this reloc is against an external symbol, we do
|
||
not want to fiddle with the addend. Otherwise, we
|
||
need to include the symbol value so that it becomes
|
||
an addend for the dynamic reloc. */
|
||
if (h != NULL)
|
||
continue;
|
||
}
|
||
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
r = _bfd_final_link_relocate (howto, input_bfd, input_section,
|
||
contents, rel->r_offset,
|
||
relocation, (bfd_vma) 0);
|
||
|
||
if (r != bfd_reloc_ok)
|
||
{
|
||
switch (r)
|
||
{
|
||
default:
|
||
case bfd_reloc_outofrange:
|
||
abort ();
|
||
case bfd_reloc_overflow:
|
||
{
|
||
const char *name;
|
||
|
||
if (h != NULL)
|
||
name = h->root.root.string;
|
||
else
|
||
{
|
||
name = elf_string_from_elf_section (input_bfd,
|
||
symtab_hdr->sh_link,
|
||
sym->st_name);
|
||
if (name == NULL)
|
||
return false;
|
||
if (*name == '\0')
|
||
name = bfd_section_name (input_bfd, sec);
|
||
}
|
||
if (! ((*info->callbacks->reloc_overflow)
|
||
(info, name, howto->name, (bfd_vma) 0,
|
||
input_bfd, input_section, rel->r_offset)))
|
||
return false;
|
||
}
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Finish up dynamic symbol handling. We set the contents of various
|
||
dynamic sections here. */
|
||
|
||
static boolean
|
||
elf_i386_finish_dynamic_symbol (output_bfd, info, h, sym)
|
||
bfd *output_bfd;
|
||
struct bfd_link_info *info;
|
||
struct elf_link_hash_entry *h;
|
||
Elf_Internal_Sym *sym;
|
||
{
|
||
bfd *dynobj;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
|
||
if (h->plt_offset != (bfd_vma) -1)
|
||
{
|
||
asection *splt;
|
||
asection *sgot;
|
||
asection *srel;
|
||
bfd_vma plt_index;
|
||
bfd_vma got_offset;
|
||
Elf_Internal_Rel rel;
|
||
|
||
/* This symbol has an entry in the procedure linkage table. Set
|
||
it up. */
|
||
|
||
BFD_ASSERT (h->dynindx != -1);
|
||
|
||
splt = bfd_get_section_by_name (dynobj, ".plt");
|
||
sgot = bfd_get_section_by_name (dynobj, ".got.plt");
|
||
srel = bfd_get_section_by_name (dynobj, ".rel.plt");
|
||
BFD_ASSERT (splt != NULL && sgot != NULL && srel != NULL);
|
||
|
||
/* Get the index in the procedure linkage table which
|
||
corresponds to this symbol. This is the index of this symbol
|
||
in all the symbols for which we are making plt entries. The
|
||
first entry in the procedure linkage table is reserved. */
|
||
plt_index = h->plt_offset / PLT_ENTRY_SIZE - 1;
|
||
|
||
/* Get the offset into the .got table of the entry that
|
||
corresponds to this function. Each .got entry is 4 bytes.
|
||
The first three are reserved. */
|
||
got_offset = (plt_index + 3) * 4;
|
||
|
||
/* Fill in the entry in the procedure linkage table. */
|
||
if (! info->shared)
|
||
{
|
||
memcpy (splt->contents + h->plt_offset, elf_i386_plt_entry,
|
||
PLT_ENTRY_SIZE);
|
||
bfd_put_32 (output_bfd,
|
||
(sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ got_offset),
|
||
splt->contents + h->plt_offset + 2);
|
||
}
|
||
else
|
||
{
|
||
memcpy (splt->contents + h->plt_offset, elf_i386_pic_plt_entry,
|
||
PLT_ENTRY_SIZE);
|
||
bfd_put_32 (output_bfd, got_offset,
|
||
splt->contents + h->plt_offset + 2);
|
||
}
|
||
|
||
bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
|
||
splt->contents + h->plt_offset + 7);
|
||
bfd_put_32 (output_bfd, - (h->plt_offset + PLT_ENTRY_SIZE),
|
||
splt->contents + h->plt_offset + 12);
|
||
|
||
/* Fill in the entry in the global offset table. */
|
||
bfd_put_32 (output_bfd,
|
||
(splt->output_section->vma
|
||
+ splt->output_offset
|
||
+ h->plt_offset
|
||
+ 6),
|
||
sgot->contents + got_offset);
|
||
|
||
/* Fill in the entry in the .rel.plt section. */
|
||
rel.r_offset = (sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ got_offset);
|
||
rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
|
||
bfd_elf32_swap_reloc_out (output_bfd, &rel,
|
||
((Elf32_External_Rel *) srel->contents
|
||
+ plt_index));
|
||
|
||
if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
|
||
{
|
||
/* Mark the symbol as undefined, rather than as defined in
|
||
the .plt section. Leave the value alone. */
|
||
sym->st_shndx = SHN_UNDEF;
|
||
}
|
||
}
|
||
|
||
if (h->got_offset != (bfd_vma) -1)
|
||
{
|
||
asection *sgot;
|
||
asection *srel;
|
||
Elf_Internal_Rel rel;
|
||
|
||
/* This symbol has an entry in the global offset table. Set it
|
||
up. */
|
||
|
||
BFD_ASSERT (h->dynindx != -1);
|
||
|
||
sgot = bfd_get_section_by_name (dynobj, ".got");
|
||
srel = bfd_get_section_by_name (dynobj, ".rel.got");
|
||
BFD_ASSERT (sgot != NULL && srel != NULL);
|
||
|
||
bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got_offset);
|
||
|
||
rel.r_offset = (sgot->output_section->vma
|
||
+ sgot->output_offset
|
||
+ h->got_offset);
|
||
rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT);
|
||
bfd_elf32_swap_reloc_out (output_bfd, &rel,
|
||
((Elf32_External_Rel *) srel->contents
|
||
+ srel->reloc_count));
|
||
++srel->reloc_count;
|
||
}
|
||
|
||
if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
|
||
{
|
||
asection *s;
|
||
Elf_Internal_Rel rel;
|
||
|
||
/* This symbol needs a copy reloc. Set it up. */
|
||
|
||
BFD_ASSERT (h->dynindx != -1
|
||
&& h->root.type == bfd_link_hash_defined);
|
||
|
||
s = bfd_get_section_by_name (h->root.u.def.section->owner,
|
||
".rel.bss");
|
||
BFD_ASSERT (s != NULL);
|
||
|
||
rel.r_offset = (h->root.u.def.value
|
||
+ h->root.u.def.section->output_section->vma
|
||
+ h->root.u.def.section->output_offset);
|
||
rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY);
|
||
bfd_elf32_swap_reloc_out (output_bfd, &rel,
|
||
((Elf32_External_Rel *) s->contents
|
||
+ s->reloc_count));
|
||
++s->reloc_count;
|
||
}
|
||
|
||
/* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
|
||
if (strcmp (h->root.root.string, "_DYNAMIC") == 0
|
||
|| strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
|
||
sym->st_shndx = SHN_ABS;
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Finish up the dynamic sections. */
|
||
|
||
static boolean
|
||
elf_i386_finish_dynamic_sections (output_bfd, info)
|
||
bfd *output_bfd;
|
||
struct bfd_link_info *info;
|
||
{
|
||
bfd *dynobj;
|
||
asection *sgot;
|
||
asection *sdyn;
|
||
|
||
dynobj = elf_hash_table (info)->dynobj;
|
||
|
||
sgot = bfd_get_section_by_name (dynobj, ".got.plt");
|
||
BFD_ASSERT (sgot != NULL);
|
||
sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
|
||
|
||
if (elf_hash_table (info)->dynamic_sections_created)
|
||
{
|
||
asection *splt;
|
||
Elf32_External_Dyn *dyncon, *dynconend;
|
||
|
||
splt = bfd_get_section_by_name (dynobj, ".plt");
|
||
BFD_ASSERT (splt != NULL && sdyn != NULL);
|
||
|
||
dyncon = (Elf32_External_Dyn *) sdyn->contents;
|
||
dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
|
||
for (; dyncon < dynconend; dyncon++)
|
||
{
|
||
Elf_Internal_Dyn dyn;
|
||
const char *name;
|
||
asection *s;
|
||
|
||
bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
|
||
|
||
switch (dyn.d_tag)
|
||
{
|
||
default:
|
||
break;
|
||
|
||
case DT_PLTGOT:
|
||
name = ".got";
|
||
goto get_vma;
|
||
case DT_JMPREL:
|
||
name = ".rel.plt";
|
||
get_vma:
|
||
s = bfd_get_section_by_name (output_bfd, name);
|
||
BFD_ASSERT (s != NULL);
|
||
dyn.d_un.d_ptr = s->vma;
|
||
bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
|
||
break;
|
||
|
||
case DT_PLTRELSZ:
|
||
s = bfd_get_section_by_name (output_bfd, ".rel.plt");
|
||
BFD_ASSERT (s != NULL);
|
||
if (s->_cooked_size != 0)
|
||
dyn.d_un.d_val = s->_cooked_size;
|
||
else
|
||
dyn.d_un.d_val = s->_raw_size;
|
||
bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
|
||
break;
|
||
|
||
case DT_RELSZ:
|
||
/* My reading of the SVR4 ABI indicates that the
|
||
procedure linkage table relocs (DT_JMPREL) should be
|
||
included in the overall relocs (DT_REL). This is
|
||
what Solaris does. However, UnixWare can not handle
|
||
that case. Therefore, we override the DT_RELSZ entry
|
||
here to make it not include the JMPREL relocs. Since
|
||
the linker script arranges for .rel.plt to follow all
|
||
other relocation sections, we don't have to worry
|
||
about changing the DT_REL entry. */
|
||
s = bfd_get_section_by_name (output_bfd, ".rel.plt");
|
||
if (s != NULL)
|
||
{
|
||
if (s->_cooked_size != 0)
|
||
dyn.d_un.d_val -= s->_cooked_size;
|
||
else
|
||
dyn.d_un.d_val -= s->_raw_size;
|
||
}
|
||
bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Fill in the first entry in the procedure linkage table. */
|
||
if (splt->_raw_size > 0)
|
||
{
|
||
if (info->shared)
|
||
memcpy (splt->contents, elf_i386_pic_plt0_entry, PLT_ENTRY_SIZE);
|
||
else
|
||
{
|
||
memcpy (splt->contents, elf_i386_plt0_entry, PLT_ENTRY_SIZE);
|
||
bfd_put_32 (output_bfd,
|
||
sgot->output_section->vma + sgot->output_offset + 4,
|
||
splt->contents + 2);
|
||
bfd_put_32 (output_bfd,
|
||
sgot->output_section->vma + sgot->output_offset + 8,
|
||
splt->contents + 8);
|
||
}
|
||
}
|
||
|
||
/* UnixWare sets the entsize of .plt to 4, although that doesn't
|
||
really seem like the right value. */
|
||
elf_section_data (splt->output_section)->this_hdr.sh_entsize = 4;
|
||
}
|
||
|
||
/* Fill in the first three entries in the global offset table. */
|
||
if (sgot->_raw_size > 0)
|
||
{
|
||
if (sdyn == NULL)
|
||
bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents);
|
||
else
|
||
bfd_put_32 (output_bfd,
|
||
sdyn->output_section->vma + sdyn->output_offset,
|
||
sgot->contents);
|
||
bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 4);
|
||
bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 8);
|
||
}
|
||
|
||
elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4;
|
||
|
||
return true;
|
||
}
|
||
|
||
#define TARGET_LITTLE_SYM bfd_elf32_i386_vec
|
||
#define TARGET_LITTLE_NAME "elf32-i386"
|
||
#define ELF_ARCH bfd_arch_i386
|
||
#define ELF_MACHINE_CODE EM_386
|
||
#define elf_info_to_howto elf_i386_info_to_howto
|
||
#define elf_info_to_howto_rel elf_i386_info_to_howto_rel
|
||
#define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
|
||
#define ELF_MAXPAGESIZE 0x1000
|
||
#define elf_backend_create_dynamic_sections \
|
||
elf_i386_create_dynamic_sections
|
||
#define elf_backend_check_relocs elf_i386_check_relocs
|
||
#define elf_backend_adjust_dynamic_symbol \
|
||
elf_i386_adjust_dynamic_symbol
|
||
#define elf_backend_size_dynamic_sections \
|
||
elf_i386_size_dynamic_sections
|
||
#define elf_backend_relocate_section elf_i386_relocate_section
|
||
#define elf_backend_finish_dynamic_symbol \
|
||
elf_i386_finish_dynamic_symbol
|
||
#define elf_backend_finish_dynamic_sections \
|
||
elf_i386_finish_dynamic_sections
|
||
|
||
#include "elf32-target.h"
|