/* Intel 80386/80486-specific support for 32-bit ELF
- Copyright 1993 Free Software Foundation, Inc.
+ Copyright 1993, 1994, 1995, 1996 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
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. */
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "bfd.h"
#include "sysdep.h"
#include "bfdlink.h"
#include "libbfd.h"
-#include "libelf.h"
+#include "elf-bfd.h"
-static CONST struct reloc_howto_struct *elf_i386_reloc_type_lookup
+static reloc_howto_type *elf_i386_reloc_type_lookup
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 *));
static boolean elf_i386_check_relocs
PARAMS ((bfd *, struct bfd_link_info *, asection *,
const Elf_Internal_Rela *));
#define TRACE(str)
#endif
-static CONST struct reloc_howto_struct *
+static reloc_howto_type *
elf_i386_reloc_type_lookup (abfd, code)
bfd *abfd;
bfd_reloc_code_real_type code;
/* The first entry in an absolute procedure linkage table looks like
this. See the SVR4 ABI i386 supplement to see how this works. */
-static bfd_byte elf_i386_plt0_entry[PLT_ENTRY_SIZE] =
+static const bfd_byte elf_i386_plt0_entry[PLT_ENTRY_SIZE] =
{
0xff, 0x35, /* pushl contents of address */
0, 0, 0, 0, /* replaced with address of .got + 4. */
/* Subsequent entries in an absolute procedure linkage table look like
this. */
-static bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
+static const bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
{
0xff, 0x25, /* jmp indirect */
0, 0, 0, 0, /* replaced with address of this symbol in .got. */
/* The first entry in a PIC procedure linkage table look like this. */
-static bfd_byte elf_i386_pic_plt0_entry[PLT_ENTRY_SIZE] =
+static const bfd_byte elf_i386_pic_plt0_entry[PLT_ENTRY_SIZE] =
{
0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */
0xff, 0xa3, 8, 0, 0, 0, /* jmp *8(%ebx) */
/* Subsequent entries in a PIC procedure linkage table look like this. */
-static bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] =
+static const 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. */
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. */
rel_end = relocs + sec->reloc_count;
for (rel = relocs; rel < rel_end; rel++)
{
- long r_symndx;
+ unsigned long r_symndx;
struct elf_link_hash_entry *h;
r_symndx = ELF32_R_SYM (rel->r_info);
case R_386_GOTOFF:
case R_386_GOTPC:
elf_hash_table (info)->dynobj = dynobj = abfd;
- if (! elf_i386_create_got_section (dynobj, info))
+ if (! _bfd_elf_create_got_section (dynobj, info))
return false;
break;
if (local_got_offsets == NULL)
{
size_t size;
- register int i;
+ register unsigned 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;
- }
+ 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;
case R_386_32:
case R_386_PC32:
if (info->shared
- && (sec->flags & SEC_ALLOC) != 0)
+ && (sec->flags & SEC_ALLOC) != 0
+ && (ELF32_R_TYPE (rel->r_info) != R_386_PC32 || h != NULL))
{
- /* When creating a shared object, we must output a
- R_386_RELATIVE reloc for this location. We create a
- reloc section in dynobj and make room for this reloc. */
+ /* 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
+ name = (bfd_elf_string_from_elf_section
(abfd,
elf_elfheader (abfd)->e_shstrndx,
elf_section_data (sec)->rel_hdr.sh_name));
/* Make sure we know what is going on here. */
BFD_ASSERT (dynobj != NULL
- && h->root.type == bfd_link_hash_defined
- && (bfd_get_flavour (h->root.u.def.section->owner)
- == bfd_target_elf_flavour)
&& ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
+ || h->weakdef != NULL
|| ((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.u.def.section->output_section == NULL)));
+ & ELF_LINK_HASH_DEF_REGULAR) == 0)));
/* If this is a function, put it in the procedure linkage table. We
will fill in the contents of the procedure linkage table later,
if (s->_raw_size == 0)
s->_raw_size += PLT_ENTRY_SIZE;
- /* Set the symbol to this location in the .plt. */
- h->root.u.def.section = s;
- h->root.u.def.value = s->_raw_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;
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);
+ BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
+ || h->weakdef->root.type == bfd_link_hash_defweak);
h->root.u.def.section = h->weakdef->root.u.def.section;
h->root.u.def.value = h->weakdef->root.u.def.value;
return true;
/* 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;
+ {
+ relocs = true;
+
+ /* If this relocation section applies to a read only
+ section, then we probably need a DT_TEXTREL
+ entry. The entries in the .rel.plt section
+ really apply to the .got section, which we
+ created ourselves and so know is not readonly. */
+ 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. */
/* 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;
- }
+ return false;
}
if (elf_hash_table (info)->dynamic_sections_created)
for (; rel < relend; rel++)
{
int r_type;
- const reloc_howto_type *howto;
- long r_symndx;
+ reloc_howto_type *howto;
+ unsigned long r_symndx;
struct elf_link_hash_entry *h;
Elf_Internal_Sym *sym;
asection *sec;
else
{
h = sym_hashes[r_symndx - symtab_hdr->sh_info];
- if (h->root.type == bfd_link_hash_defined)
+ while (h->root.type == bfd_link_hash_indirect
+ || h->root.type == bfd_link_hash_warning)
+ h = (struct elf_link_hash_entry *) h->root.u.i.link;
+ if (h->root.type == bfd_link_hash_defined
+ || h->root.type == bfd_link_hash_defweak)
{
sec = h->root.u.def.section;
- relocation = (h->root.u.def.value
- + sec->output_section->vma
- + sec->output_offset);
+ 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
+ || ! info->symbolic
+ || (h->elf_link_hash_flags
+ & ELF_LINK_HASH_DEF_REGULAR) == 0))
+ || (info->shared
+ && (! info->symbolic
+ || (h->elf_link_hash_flags
+ & ELF_LINK_HASH_DEF_REGULAR) == 0)
+ && (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)
+ else if (h->root.type == bfd_link_hash_undefweak)
relocation = 0;
- else if (info->shared)
+ else if (info->shared && !info->symbolic)
relocation = 0;
else
{
off = h->got_offset;
BFD_ASSERT (off != (bfd_vma) -1);
- if (! elf_hash_table (info)->dynamic_sections_created)
+ if (! elf_hash_table (info)->dynamic_sections_created
+ || (info->shared
+ && info->symbolic
+ && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
{
- /* 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.
+ /* This is actually a static link, or it is a
+ -Bsymbolic link and the symbol is defined
+ locally. 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
if (h->plt_offset == (bfd_vma) -1)
{
/* We didn't make a PLT entry for this symbol. This
- happens when statically linking PIC code. */
+ happens when statically linking PIC code, or when
+ using -Bsymbolic. */
break;
}
case R_386_32:
case R_386_PC32:
if (info->shared
- && (input_section->flags & SEC_ALLOC) != 0)
+ && (input_section->flags & SEC_ALLOC) != 0
+ && (r_type != R_386_PC32
+ || (h != NULL
+ && (! info->symbolic
+ || (h->elf_link_hash_flags
+ & ELF_LINK_HASH_DEF_REGULAR) == 0))))
{
Elf_Internal_Rel outrel;
+ boolean relocate;
/* When generating a shared object, these relocations
are copied into the output file to be resolved at run
{
const char *name;
- name = (elf_string_from_elf_section
+ name = (bfd_elf_string_from_elf_section
(input_bfd,
elf_elfheader (input_bfd)->e_shstrndx,
elf_section_data (input_section)->rel_hdr.sh_name));
if (r_type == R_386_PC32)
{
BFD_ASSERT (h != NULL && h->dynindx != -1);
+ relocate = false;
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);
+ if (h == NULL
+ || (info->symbolic
+ && (h->elf_link_hash_flags
+ & ELF_LINK_HASH_DEF_REGULAR) != 0))
+ {
+ relocate = true;
+ outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
+ }
else
{
- BFD_ASSERT (h->dynindx != (bfd_vma) -1);
+ BFD_ASSERT (h->dynindx != -1);
+ relocate = false;
outrel.r_info = ELF32_R_INFO (h->dynindx, R_386_32);
}
}
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)
+ if (! relocate)
continue;
}
name = h->root.root.string;
else
{
- name = elf_string_from_elf_section (input_bfd,
- symtab_hdr->sh_link,
- sym->st_name);
+ name = bfd_elf_string_from_elf_section (input_bfd,
+ symtab_hdr->sh_link,
+ sym->st_name);
if (name == NULL)
return false;
if (*name == '\0')
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);
+ + (h->got_offset &~ 1));
+
+ /* If this is a -Bsymbolic link, and the symbol is defined
+ locally, we just want to emit a RELATIVE reloc. The entry in
+ the global offset table will already have been initialized in
+ the relocate_section function. */
+ if (info->shared
+ && info->symbolic
+ && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
+ rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
+ else
+ {
+ bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 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));
/* This symbol needs a copy reloc. Set it up. */
BFD_ASSERT (h->dynindx != -1
- && h->root.type == bfd_link_hash_defined);
+ && (h->root.type == bfd_link_hash_defined
+ || h->root.type == bfd_link_hash_defweak));
s = bfd_get_section_by_name (h->root.u.def.section->owner,
".rel.bss");
#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
+ _bfd_elf_create_dynamic_sections
#define elf_backend_check_relocs elf_i386_check_relocs
#define elf_backend_adjust_dynamic_symbol \
elf_i386_adjust_dynamic_symbol
elf_i386_finish_dynamic_symbol
#define elf_backend_finish_dynamic_sections \
elf_i386_finish_dynamic_sections
+#define elf_backend_want_got_plt 1
+#define elf_backend_plt_readonly 1
+#define elf_backend_want_plt_sym 0
#include "elf32-target.h"