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binutils-gdb/bfd/elflink.h
Alan Modra 140f6c8e6d * elf-bfd.h (struct elf_reloc_cookie): Add r_sym_shift field. 
* elflink.h: Replace all occurrences of sizeof (Elf_External_*)
	where Elf_External_* is different for 64 and 32 bit, with
	corresponding elf_size_info field.
	(struct elf_final_link_info): Use "bfd_byte *" instead
	of "Elf_External_Sym *" for external_syms and symbuf.
	(elf_link_adjust_relocs): Set up r_type_mask and r_sym_shift local
	vars and use instead of ELF_R_INFO and ELF_R_TYPE macros.
	(struct elf_link_sort_rela): Add "sym_mask" alias for "offset".
	(elf_link_sort_cmp1): Use sym_mask field instead of ELF_R_SYM.
	(elf_link_sort_cmp2): Adjust.
	(elf_link_sort_relocs): Set up r_sym_mask local var instead of
	using ELF_R_SYM macro.  Set u.sym_mask.
	(elf_bfd_final_link): Call _bfd_elf_stringtab_init instead of macro
	version, elf_stringtab_init.  Ditto for bfd_section_from_elf_index
	vs. section_from_elf_index.  Adjust Elf_External_Sym pointer
	arithmetic.  Pass bed to elf_link_flush_output_syms.  Adjust
	Elf_External_Dyn pointer arithmentic.  Use bed swap_dyn_in and
	swap_syn_out functions.  Rearrange dyn swap in/out switch.
	(elf_link_output_sym): Adjust Elf_External_Sym pointer arithmentic.
	Pass bed to elf_link_flush_output_syms.  Use bed swap_symbol_out.
	(elf_link_flush_output_syms): Add elf_backend_data arg.
	(elf_link_check_versioned_symbol): Likewise.
	(elf_link_output_extsym): Pass bed to elf_link_check_versioned_symbol.
	Adjust Elf_External_Sym pointer arithmetic.  Use bed swap_symbol_out.
	(elf_link_input_bfd): Use bfd_section_from_elf_index.  Set up
	r_type_mask and r_sym_shift local vars and use instead of ELF_R_SYM,
	ELF_R_TYPE and ELF_R_INFO macros.
	(elf_reloc_link_order): Select ELF32_R_INFO or ELF64_R_INFO invocation
	based on size rather than using ELF_R_INFO.
	(elf_gc_mark): Set up r_sym_shift local var and use instead of
	ELF_R_SYM macro.
	(struct alloc_got_off_arg): New.
	(elf_gc_common_finalize_got_offsets): Use elf_size_info instead of
	ARCH_SIZE.  Pass get entry size down to elf_gc_allocate_got_offsets.
	(elf_gc_allocate_got_offsets): Adjust.
	(elf_reloc_symbol_deleted_p): Usee cookie.r_sym_shift instead of
	ELF_R_SYM.  Use bfd_section_from_elf_index.
	(elf_bfd_discard_info): Set cookie.r_sym_shift.
	* elfcode.h (elf_stringtab_init, section_from_elf_index): Delete.
	(elf_slurp_symbol_table): Use bfd_section_from_elf_index.
2004-03-27 10:08:59 +00:00

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/* ELF linker support.
Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* ELF linker code. */
static bfd_boolean elf_section_ignore_discarded_relocs (asection *);
/* Final phase of ELF linker. */
/* A structure we use to avoid passing large numbers of arguments. */
struct elf_final_link_info
{
/* General link information. */
struct bfd_link_info *info;
/* Output BFD. */
bfd *output_bfd;
/* Symbol string table. */
struct bfd_strtab_hash *symstrtab;
/* .dynsym section. */
asection *dynsym_sec;
/* .hash section. */
asection *hash_sec;
/* symbol version section (.gnu.version). */
asection *symver_sec;
/* Buffer large enough to hold contents of any section. */
bfd_byte *contents;
/* Buffer large enough to hold external relocs of any section. */
void *external_relocs;
/* Buffer large enough to hold internal relocs of any section. */
Elf_Internal_Rela *internal_relocs;
/* Buffer large enough to hold external local symbols of any input
BFD. */
bfd_byte *external_syms;
/* And a buffer for symbol section indices. */
Elf_External_Sym_Shndx *locsym_shndx;
/* Buffer large enough to hold internal local symbols of any input
BFD. */
Elf_Internal_Sym *internal_syms;
/* Array large enough to hold a symbol index for each local symbol
of any input BFD. */
long *indices;
/* Array large enough to hold a section pointer for each local
symbol of any input BFD. */
asection **sections;
/* Buffer to hold swapped out symbols. */
bfd_byte *symbuf;
/* And one for symbol section indices. */
Elf_External_Sym_Shndx *symshndxbuf;
/* Number of swapped out symbols in buffer. */
size_t symbuf_count;
/* Number of symbols which fit in symbuf. */
size_t symbuf_size;
/* And same for symshndxbuf. */
size_t shndxbuf_size;
};
static bfd_boolean elf_link_output_sym
(struct elf_final_link_info *, const char *, Elf_Internal_Sym *, asection *,
struct elf_link_hash_entry *);
static bfd_boolean elf_link_flush_output_syms
(struct elf_final_link_info *, const struct elf_backend_data *);
static bfd_boolean elf_link_output_extsym
(struct elf_link_hash_entry *, void *);
static bfd_boolean elf_link_input_bfd
(struct elf_final_link_info *, bfd *);
static bfd_boolean elf_reloc_link_order
(bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *);
/* This struct is used to pass information to elf_link_output_extsym. */
struct elf_outext_info
{
bfd_boolean failed;
bfd_boolean localsyms;
struct elf_final_link_info *finfo;
};
/* When performing a relocatable link, the input relocations are
preserved. But, if they reference global symbols, the indices
referenced must be updated. Update all the relocations in
REL_HDR (there are COUNT of them), using the data in REL_HASH. */
static void
elf_link_adjust_relocs (bfd *abfd,
Elf_Internal_Shdr *rel_hdr,
unsigned int count,
struct elf_link_hash_entry **rel_hash)
{
unsigned int i;
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
bfd_byte *erela;
void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
bfd_vma r_type_mask;
int r_sym_shift;
if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
{
swap_in = bed->s->swap_reloc_in;
swap_out = bed->s->swap_reloc_out;
}
else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
{
swap_in = bed->s->swap_reloca_in;
swap_out = bed->s->swap_reloca_out;
}
else
abort ();
if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
abort ();
if (bed->s->arch_size == 32)
{
r_type_mask = 0xff;
r_sym_shift = 8;
}
else
{
r_type_mask = 0xffffffff;
r_sym_shift = 32;
}
erela = rel_hdr->contents;
for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
{
Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
unsigned int j;
if (*rel_hash == NULL)
continue;
BFD_ASSERT ((*rel_hash)->indx >= 0);
(*swap_in) (abfd, erela, irela);
for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
| (irela[j].r_info & r_type_mask));
(*swap_out) (abfd, irela, erela);
}
}
struct elf_link_sort_rela
{
union {
bfd_vma offset;
bfd_vma sym_mask;
} u;
enum elf_reloc_type_class type;
/* We use this as an array of size int_rels_per_ext_rel. */
Elf_Internal_Rela rela[1];
};
static int
elf_link_sort_cmp1 (const void *A, const void *B)
{
const struct elf_link_sort_rela *a = A;
const struct elf_link_sort_rela *b = B;
int relativea, relativeb;
relativea = a->type == reloc_class_relative;
relativeb = b->type == reloc_class_relative;
if (relativea < relativeb)
return 1;
if (relativea > relativeb)
return -1;
if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
return -1;
if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
return 1;
if (a->rela->r_offset < b->rela->r_offset)
return -1;
if (a->rela->r_offset > b->rela->r_offset)
return 1;
return 0;
}
static int
elf_link_sort_cmp2 (const void *A, const void *B)
{
const struct elf_link_sort_rela *a = A;
const struct elf_link_sort_rela *b = B;
int copya, copyb;
if (a->u.offset < b->u.offset)
return -1;
if (a->u.offset > b->u.offset)
return 1;
copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
if (copya < copyb)
return -1;
if (copya > copyb)
return 1;
if (a->rela->r_offset < b->rela->r_offset)
return -1;
if (a->rela->r_offset > b->rela->r_offset)
return 1;
return 0;
}
static size_t
elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
{
asection *reldyn;
bfd_size_type count, size;
size_t i, ret, sort_elt, ext_size;
bfd_byte *sort, *s_non_relative, *p;
struct elf_link_sort_rela *sq;
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
int i2e = bed->s->int_rels_per_ext_rel;
void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
struct bfd_link_order *lo;
bfd_vma r_sym_mask;
reldyn = bfd_get_section_by_name (abfd, ".rela.dyn");
if (reldyn == NULL || reldyn->_raw_size == 0)
{
reldyn = bfd_get_section_by_name (abfd, ".rel.dyn");
if (reldyn == NULL || reldyn->_raw_size == 0)
return 0;
ext_size = bed->s->sizeof_rel;
swap_in = bed->s->swap_reloc_in;
swap_out = bed->s->swap_reloc_out;
}
else
{
ext_size = bed->s->sizeof_rela;
swap_in = bed->s->swap_reloca_in;
swap_out = bed->s->swap_reloca_out;
}
count = reldyn->_raw_size / ext_size;
size = 0;
for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
if (lo->type == bfd_indirect_link_order)
{
asection *o = lo->u.indirect.section;
size += o->_raw_size;
}
if (size != reldyn->_raw_size)
return 0;
sort_elt = (sizeof (struct elf_link_sort_rela)
+ (i2e - 1) * sizeof (Elf_Internal_Rela));
sort = bfd_zmalloc (sort_elt * count);
if (sort == NULL)
{
(*info->callbacks->warning)
(info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
return 0;
}
if (bed->s->arch_size == 32)
r_sym_mask = ~(bfd_vma) 0xff;
else
r_sym_mask = ~(bfd_vma) 0xffffffff;
for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
if (lo->type == bfd_indirect_link_order)
{
bfd_byte *erel, *erelend;
asection *o = lo->u.indirect.section;
erel = o->contents;
erelend = o->contents + o->_raw_size;
p = sort + o->output_offset / ext_size * sort_elt;
while (erel < erelend)
{
struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
(*swap_in) (abfd, erel, s->rela);
s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
s->u.sym_mask = r_sym_mask;
p += sort_elt;
erel += ext_size;
}
}
qsort (sort, count, sort_elt, elf_link_sort_cmp1);
for (i = 0, p = sort; i < count; i++, p += sort_elt)
{
struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
if (s->type != reloc_class_relative)
break;
}
ret = i;
s_non_relative = p;
sq = (struct elf_link_sort_rela *) s_non_relative;
for (; i < count; i++, p += sort_elt)
{
struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
sq = sp;
sp->u.offset = sq->rela->r_offset;
}
qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
if (lo->type == bfd_indirect_link_order)
{
bfd_byte *erel, *erelend;
asection *o = lo->u.indirect.section;
erel = o->contents;
erelend = o->contents + o->_raw_size;
p = sort + o->output_offset / ext_size * sort_elt;
while (erel < erelend)
{
struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
(*swap_out) (abfd, s->rela, erel);
p += sort_elt;
erel += ext_size;
}
}
free (sort);
*psec = reldyn;
return ret;
}
/* Do the final step of an ELF link. */
bfd_boolean
elf_bfd_final_link (bfd *abfd, struct bfd_link_info *info)
{
bfd_boolean dynamic;
bfd_boolean emit_relocs;
bfd *dynobj;
struct elf_final_link_info finfo;
register asection *o;
register struct bfd_link_order *p;
register bfd *sub;
bfd_size_type max_contents_size;
bfd_size_type max_external_reloc_size;
bfd_size_type max_internal_reloc_count;
bfd_size_type max_sym_count;
bfd_size_type max_sym_shndx_count;
file_ptr off;
Elf_Internal_Sym elfsym;
unsigned int i;
Elf_Internal_Shdr *symtab_hdr;
Elf_Internal_Shdr *symtab_shndx_hdr;
Elf_Internal_Shdr *symstrtab_hdr;
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
struct elf_outext_info eoinfo;
bfd_boolean merged;
size_t relativecount = 0;
asection *reldyn = 0;
bfd_size_type amt;
if (! is_elf_hash_table (info->hash))
return FALSE;
if (info->shared)
abfd->flags |= DYNAMIC;
dynamic = elf_hash_table (info)->dynamic_sections_created;
dynobj = elf_hash_table (info)->dynobj;
emit_relocs = (info->relocatable
|| info->emitrelocations
|| bed->elf_backend_emit_relocs);
finfo.info = info;
finfo.output_bfd = abfd;
finfo.symstrtab = _bfd_elf_stringtab_init ();
if (finfo.symstrtab == NULL)
return FALSE;
if (! dynamic)
{
finfo.dynsym_sec = NULL;
finfo.hash_sec = NULL;
finfo.symver_sec = NULL;
}
else
{
finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
/* Note that it is OK if symver_sec is NULL. */
}
finfo.contents = NULL;
finfo.external_relocs = NULL;
finfo.internal_relocs = NULL;
finfo.external_syms = NULL;
finfo.locsym_shndx = NULL;
finfo.internal_syms = NULL;
finfo.indices = NULL;
finfo.sections = NULL;
finfo.symbuf = NULL;
finfo.symshndxbuf = NULL;
finfo.symbuf_count = 0;
finfo.shndxbuf_size = 0;
/* Count up the number of relocations we will output for each output
section, so that we know the sizes of the reloc sections. We
also figure out some maximum sizes. */
max_contents_size = 0;
max_external_reloc_size = 0;
max_internal_reloc_count = 0;
max_sym_count = 0;
max_sym_shndx_count = 0;
merged = FALSE;
for (o = abfd->sections; o != NULL; o = o->next)
{
struct bfd_elf_section_data *esdo = elf_section_data (o);
o->reloc_count = 0;
for (p = o->link_order_head; p != NULL; p = p->next)
{
unsigned int reloc_count = 0;
struct bfd_elf_section_data *esdi = NULL;
unsigned int *rel_count1;
if (p->type == bfd_section_reloc_link_order
|| p->type == bfd_symbol_reloc_link_order)
reloc_count = 1;
else if (p->type == bfd_indirect_link_order)
{
asection *sec;
sec = p->u.indirect.section;
esdi = elf_section_data (sec);
/* Mark all sections which are to be included in the
link. This will normally be every section. We need
to do this so that we can identify any sections which
the linker has decided to not include. */
sec->linker_mark = TRUE;
if (sec->flags & SEC_MERGE)
merged = TRUE;
if (info->relocatable || info->emitrelocations)
reloc_count = sec->reloc_count;
else if (bed->elf_backend_count_relocs)
{
Elf_Internal_Rela * relocs;
relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
info->keep_memory);
reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs);
if (elf_section_data (o)->relocs != relocs)
free (relocs);
}
if (sec->_raw_size > max_contents_size)
max_contents_size = sec->_raw_size;
if (sec->_cooked_size > max_contents_size)
max_contents_size = sec->_cooked_size;
/* We are interested in just local symbols, not all
symbols. */
if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
&& (sec->owner->flags & DYNAMIC) == 0)
{
size_t sym_count;
if (elf_bad_symtab (sec->owner))
sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
/ bed->s->sizeof_sym);
else
sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
if (sym_count > max_sym_count)
max_sym_count = sym_count;
if (sym_count > max_sym_shndx_count
&& elf_symtab_shndx (sec->owner) != 0)
max_sym_shndx_count = sym_count;
if ((sec->flags & SEC_RELOC) != 0)
{
size_t ext_size;
ext_size = elf_section_data (sec)->rel_hdr.sh_size;
if (ext_size > max_external_reloc_size)
max_external_reloc_size = ext_size;
if (sec->reloc_count > max_internal_reloc_count)
max_internal_reloc_count = sec->reloc_count;
}
}
}
if (reloc_count == 0)
continue;
o->reloc_count += reloc_count;
/* MIPS may have a mix of REL and RELA relocs on sections.
To support this curious ABI we keep reloc counts in
elf_section_data too. We must be careful to add the
relocations from the input section to the right output
count. FIXME: Get rid of one count. We have
o->reloc_count == esdo->rel_count + esdo->rel_count2. */
rel_count1 = &esdo->rel_count;
if (esdi != NULL)
{
bfd_boolean same_size;
bfd_size_type entsize1;
entsize1 = esdi->rel_hdr.sh_entsize;
BFD_ASSERT (entsize1 == bed->s->sizeof_rel
|| entsize1 == bed->s->sizeof_rela);
same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
if (!same_size)
rel_count1 = &esdo->rel_count2;
if (esdi->rel_hdr2 != NULL)
{
bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
unsigned int alt_count;
unsigned int *rel_count2;
BFD_ASSERT (entsize2 != entsize1
&& (entsize2 == bed->s->sizeof_rel
|| entsize2 == bed->s->sizeof_rela));
rel_count2 = &esdo->rel_count2;
if (!same_size)
rel_count2 = &esdo->rel_count;
/* The following is probably too simplistic if the
backend counts output relocs unusually. */
BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
*rel_count2 += alt_count;
reloc_count -= alt_count;
}
}
*rel_count1 += reloc_count;
}
if (o->reloc_count > 0)
o->flags |= SEC_RELOC;
else
{
/* Explicitly clear the SEC_RELOC flag. The linker tends to
set it (this is probably a bug) and if it is set
assign_section_numbers will create a reloc section. */
o->flags &=~ SEC_RELOC;
}
/* If the SEC_ALLOC flag is not set, force the section VMA to
zero. This is done in elf_fake_sections as well, but forcing
the VMA to 0 here will ensure that relocs against these
sections are handled correctly. */
if ((o->flags & SEC_ALLOC) == 0
&& ! o->user_set_vma)
o->vma = 0;
}
if (! info->relocatable && merged)
elf_link_hash_traverse (elf_hash_table (info),
_bfd_elf_link_sec_merge_syms, abfd);
/* Figure out the file positions for everything but the symbol table
and the relocs. We set symcount to force assign_section_numbers
to create a symbol table. */
bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
BFD_ASSERT (! abfd->output_has_begun);
if (! _bfd_elf_compute_section_file_positions (abfd, info))
goto error_return;
/* That created the reloc sections. Set their sizes, and assign
them file positions, and allocate some buffers. */
for (o = abfd->sections; o != NULL; o = o->next)
{
if ((o->flags & SEC_RELOC) != 0)
{
if (!(_bfd_elf_link_size_reloc_section
(abfd, &elf_section_data (o)->rel_hdr, o)))
goto error_return;
if (elf_section_data (o)->rel_hdr2
&& !(_bfd_elf_link_size_reloc_section
(abfd, elf_section_data (o)->rel_hdr2, o)))
goto error_return;
}
/* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
to count upwards while actually outputting the relocations. */
elf_section_data (o)->rel_count = 0;
elf_section_data (o)->rel_count2 = 0;
}
_bfd_elf_assign_file_positions_for_relocs (abfd);
/* We have now assigned file positions for all the sections except
.symtab and .strtab. We start the .symtab section at the current
file position, and write directly to it. We build the .strtab
section in memory. */
bfd_get_symcount (abfd) = 0;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
/* sh_name is set in prep_headers. */
symtab_hdr->sh_type = SHT_SYMTAB;
/* sh_flags, sh_addr and sh_size all start off zero. */
symtab_hdr->sh_entsize = bed->s->sizeof_sym;
/* sh_link is set in assign_section_numbers. */
/* sh_info is set below. */
/* sh_offset is set just below. */
symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
off = elf_tdata (abfd)->next_file_pos;
off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
/* Note that at this point elf_tdata (abfd)->next_file_pos is
incorrect. We do not yet know the size of the .symtab section.
We correct next_file_pos below, after we do know the size. */
/* Allocate a buffer to hold swapped out symbols. This is to avoid
continuously seeking to the right position in the file. */
if (! info->keep_memory || max_sym_count < 20)
finfo.symbuf_size = 20;
else
finfo.symbuf_size = max_sym_count;
amt = finfo.symbuf_size;
amt *= bed->s->sizeof_sym;
finfo.symbuf = bfd_malloc (amt);
if (finfo.symbuf == NULL)
goto error_return;
if (elf_numsections (abfd) > SHN_LORESERVE)
{
/* Wild guess at number of output symbols. realloc'd as needed. */
amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
finfo.shndxbuf_size = amt;
amt *= sizeof (Elf_External_Sym_Shndx);
finfo.symshndxbuf = bfd_zmalloc (amt);
if (finfo.symshndxbuf == NULL)
goto error_return;
}
/* Start writing out the symbol table. The first symbol is always a
dummy symbol. */
if (info->strip != strip_all
|| emit_relocs)
{
elfsym.st_value = 0;
elfsym.st_size = 0;
elfsym.st_info = 0;
elfsym.st_other = 0;
elfsym.st_shndx = SHN_UNDEF;
if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
NULL))
goto error_return;
}
#if 0
/* Some standard ELF linkers do this, but we don't because it causes
bootstrap comparison failures. */
/* Output a file symbol for the output file as the second symbol.
We output this even if we are discarding local symbols, although
I'm not sure if this is correct. */
elfsym.st_value = 0;
elfsym.st_size = 0;
elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
elfsym.st_other = 0;
elfsym.st_shndx = SHN_ABS;
if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
&elfsym, bfd_abs_section_ptr, NULL))
goto error_return;
#endif
/* Output a symbol for each section. We output these even if we are
discarding local symbols, since they are used for relocs. These
symbols have no names. We store the index of each one in the
index field of the section, so that we can find it again when
outputting relocs. */
if (info->strip != strip_all
|| emit_relocs)
{
elfsym.st_size = 0;
elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
elfsym.st_other = 0;
for (i = 1; i < elf_numsections (abfd); i++)
{
o = bfd_section_from_elf_index (abfd, i);
if (o != NULL)
o->target_index = bfd_get_symcount (abfd);
elfsym.st_shndx = i;
if (info->relocatable || o == NULL)
elfsym.st_value = 0;
else
elfsym.st_value = o->vma;
if (! elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
goto error_return;
if (i == SHN_LORESERVE - 1)
i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
}
}
/* Allocate some memory to hold information read in from the input
files. */
if (max_contents_size != 0)
{
finfo.contents = bfd_malloc (max_contents_size);
if (finfo.contents == NULL)
goto error_return;
}
if (max_external_reloc_size != 0)
{
finfo.external_relocs = bfd_malloc (max_external_reloc_size);
if (finfo.external_relocs == NULL)
goto error_return;
}
if (max_internal_reloc_count != 0)
{
amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
amt *= sizeof (Elf_Internal_Rela);
finfo.internal_relocs = bfd_malloc (amt);
if (finfo.internal_relocs == NULL)
goto error_return;
}
if (max_sym_count != 0)
{
amt = max_sym_count * bed->s->sizeof_sym;
finfo.external_syms = bfd_malloc (amt);
if (finfo.external_syms == NULL)
goto error_return;
amt = max_sym_count * sizeof (Elf_Internal_Sym);
finfo.internal_syms = bfd_malloc (amt);
if (finfo.internal_syms == NULL)
goto error_return;
amt = max_sym_count * sizeof (long);
finfo.indices = bfd_malloc (amt);
if (finfo.indices == NULL)
goto error_return;
amt = max_sym_count * sizeof (asection *);
finfo.sections = bfd_malloc (amt);
if (finfo.sections == NULL)
goto error_return;
}
if (max_sym_shndx_count != 0)
{
amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
finfo.locsym_shndx = bfd_malloc (amt);
if (finfo.locsym_shndx == NULL)
goto error_return;
}
if (elf_hash_table (info)->tls_sec)
{
bfd_vma base, end = 0;
asection *sec;
for (sec = elf_hash_table (info)->tls_sec;
sec && (sec->flags & SEC_THREAD_LOCAL);
sec = sec->next)
{
bfd_vma size = sec->_raw_size;
if (size == 0 && (sec->flags & SEC_HAS_CONTENTS) == 0)
{
struct bfd_link_order *o;
for (o = sec->link_order_head; o != NULL; o = o->next)
if (size < o->offset + o->size)
size = o->offset + o->size;
}
end = sec->vma + size;
}
base = elf_hash_table (info)->tls_sec->vma;
end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
elf_hash_table (info)->tls_size = end - base;
}
/* Since ELF permits relocations to be against local symbols, we
must have the local symbols available when we do the relocations.
Since we would rather only read the local symbols once, and we
would rather not keep them in memory, we handle all the
relocations for a single input file at the same time.
Unfortunately, there is no way to know the total number of local
symbols until we have seen all of them, and the local symbol
indices precede the global symbol indices. This means that when
we are generating relocatable output, and we see a reloc against
a global symbol, we can not know the symbol index until we have
finished examining all the local symbols to see which ones we are
going to output. To deal with this, we keep the relocations in
memory, and don't output them until the end of the link. This is
an unfortunate waste of memory, but I don't see a good way around
it. Fortunately, it only happens when performing a relocatable
link, which is not the common case. FIXME: If keep_memory is set
we could write the relocs out and then read them again; I don't
know how bad the memory loss will be. */
for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
sub->output_has_begun = FALSE;
for (o = abfd->sections; o != NULL; o = o->next)
{
for (p = o->link_order_head; p != NULL; p = p->next)
{
if (p->type == bfd_indirect_link_order
&& (bfd_get_flavour ((sub = p->u.indirect.section->owner))
== bfd_target_elf_flavour)
&& elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
{
if (! sub->output_has_begun)
{
if (! elf_link_input_bfd (&finfo, sub))
goto error_return;
sub->output_has_begun = TRUE;
}
}
else if (p->type == bfd_section_reloc_link_order
|| p->type == bfd_symbol_reloc_link_order)
{
if (! elf_reloc_link_order (abfd, info, o, p))
goto error_return;
}
else
{
if (! _bfd_default_link_order (abfd, info, o, p))
goto error_return;
}
}
}
/* Output any global symbols that got converted to local in a
version script or due to symbol visibility. We do this in a
separate step since ELF requires all local symbols to appear
prior to any global symbols. FIXME: We should only do this if
some global symbols were, in fact, converted to become local.
FIXME: Will this work correctly with the Irix 5 linker? */
eoinfo.failed = FALSE;
eoinfo.finfo = &finfo;
eoinfo.localsyms = TRUE;
elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
&eoinfo);
if (eoinfo.failed)
return FALSE;
/* That wrote out all the local symbols. Finish up the symbol table
with the global symbols. Even if we want to strip everything we
can, we still need to deal with those global symbols that got
converted to local in a version script. */
/* The sh_info field records the index of the first non local symbol. */
symtab_hdr->sh_info = bfd_get_symcount (abfd);
if (dynamic
&& finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
{
Elf_Internal_Sym sym;
bfd_byte *dynsym = finfo.dynsym_sec->contents;
long last_local = 0;
/* Write out the section symbols for the output sections. */
if (info->shared)
{
asection *s;
sym.st_size = 0;
sym.st_name = 0;
sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
sym.st_other = 0;
for (s = abfd->sections; s != NULL; s = s->next)
{
int indx;
bfd_byte *dest;
long dynindx;
indx = elf_section_data (s)->this_idx;
dynindx = elf_section_data (s)->dynindx;
BFD_ASSERT (indx > 0);
sym.st_shndx = indx;
sym.st_value = s->vma;
dest = dynsym + dynindx * bed->s->sizeof_sym;
bed->s->swap_symbol_out (abfd, &sym, dest, 0);
}
last_local = bfd_count_sections (abfd);
}
/* Write out the local dynsyms. */
if (elf_hash_table (info)->dynlocal)
{
struct elf_link_local_dynamic_entry *e;
for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
{
asection *s;
bfd_byte *dest;
sym.st_size = e->isym.st_size;
sym.st_other = e->isym.st_other;
/* Copy the internal symbol as is.
Note that we saved a word of storage and overwrote
the original st_name with the dynstr_index. */
sym = e->isym;
if (e->isym.st_shndx != SHN_UNDEF
&& (e->isym.st_shndx < SHN_LORESERVE
|| e->isym.st_shndx > SHN_HIRESERVE))
{
s = bfd_section_from_elf_index (e->input_bfd,
e->isym.st_shndx);
sym.st_shndx =
elf_section_data (s->output_section)->this_idx;
sym.st_value = (s->output_section->vma
+ s->output_offset
+ e->isym.st_value);
}
if (last_local < e->dynindx)
last_local = e->dynindx;
dest = dynsym + e->dynindx * bed->s->sizeof_sym;
bed->s->swap_symbol_out (abfd, &sym, dest, 0);
}
}
elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
last_local + 1;
}
/* We get the global symbols from the hash table. */
eoinfo.failed = FALSE;
eoinfo.localsyms = FALSE;
eoinfo.finfo = &finfo;
elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
&eoinfo);
if (eoinfo.failed)
return FALSE;
/* If backend needs to output some symbols not present in the hash
table, do it now. */
if (bed->elf_backend_output_arch_syms)
{
typedef bfd_boolean (*out_sym_func)
(void *, const char *, Elf_Internal_Sym *, asection *,
struct elf_link_hash_entry *);
if (! ((*bed->elf_backend_output_arch_syms)
(abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
return FALSE;
}
/* Flush all symbols to the file. */
if (! elf_link_flush_output_syms (&finfo, bed))
return FALSE;
/* Now we know the size of the symtab section. */
off += symtab_hdr->sh_size;
symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
if (symtab_shndx_hdr->sh_name != 0)
{
symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
symtab_shndx_hdr->sh_size = amt;
off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
off, TRUE);
if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
|| (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
return FALSE;
}
/* Finish up and write out the symbol string table (.strtab)
section. */
symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
/* sh_name was set in prep_headers. */
symstrtab_hdr->sh_type = SHT_STRTAB;
symstrtab_hdr->sh_flags = 0;
symstrtab_hdr->sh_addr = 0;
symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
symstrtab_hdr->sh_entsize = 0;
symstrtab_hdr->sh_link = 0;
symstrtab_hdr->sh_info = 0;
/* sh_offset is set just below. */
symstrtab_hdr->sh_addralign = 1;
off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
elf_tdata (abfd)->next_file_pos = off;
if (bfd_get_symcount (abfd) > 0)
{
if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
|| ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
return FALSE;
}
/* Adjust the relocs to have the correct symbol indices. */
for (o = abfd->sections; o != NULL; o = o->next)
{
if ((o->flags & SEC_RELOC) == 0)
continue;
elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
elf_section_data (o)->rel_count,
elf_section_data (o)->rel_hashes);
if (elf_section_data (o)->rel_hdr2 != NULL)
elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
elf_section_data (o)->rel_count2,
(elf_section_data (o)->rel_hashes
+ elf_section_data (o)->rel_count));
/* Set the reloc_count field to 0 to prevent write_relocs from
trying to swap the relocs out itself. */
o->reloc_count = 0;
}
if (dynamic && info->combreloc && dynobj != NULL)
relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
/* If we are linking against a dynamic object, or generating a
shared library, finish up the dynamic linking information. */
if (dynamic)
{
bfd_byte *dyncon, *dynconend;
/* Fix up .dynamic entries. */
o = bfd_get_section_by_name (dynobj, ".dynamic");
BFD_ASSERT (o != NULL);
dyncon = o->contents;
dynconend = o->contents + o->_raw_size;
for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
{
Elf_Internal_Dyn dyn;
const char *name;
unsigned int type;
bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
switch (dyn.d_tag)
{
default:
continue;
case DT_NULL:
if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
{
switch (elf_section_data (reldyn)->this_hdr.sh_type)
{
case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
default: continue;
}
dyn.d_un.d_val = relativecount;
relativecount = 0;
break;
}
continue;
case DT_INIT:
name = info->init_function;
goto get_sym;
case DT_FINI:
name = info->fini_function;
get_sym:
{
struct elf_link_hash_entry *h;
h = elf_link_hash_lookup (elf_hash_table (info), name,
FALSE, FALSE, TRUE);
if (h != NULL
&& (h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak))
{
dyn.d_un.d_val = h->root.u.def.value;
o = h->root.u.def.section;
if (o->output_section != NULL)
dyn.d_un.d_val += (o->output_section->vma
+ o->output_offset);
else
{
/* The symbol is imported from another shared
library and does not apply to this one. */
dyn.d_un.d_val = 0;
}
break;
}
}
continue;
case DT_PREINIT_ARRAYSZ:
name = ".preinit_array";
goto get_size;
case DT_INIT_ARRAYSZ:
name = ".init_array";
goto get_size;
case DT_FINI_ARRAYSZ:
name = ".fini_array";
get_size:
o = bfd_get_section_by_name (abfd, name);
if (o == NULL)
{
(*_bfd_error_handler)
(_("%s: could not find output section %s"),
bfd_get_filename (abfd), name);
goto error_return;
}
if (o->_raw_size == 0)
(*_bfd_error_handler)
(_("warning: %s section has zero size"), name);
dyn.d_un.d_val = o->_raw_size;
break;
case DT_PREINIT_ARRAY:
name = ".preinit_array";
goto get_vma;
case DT_INIT_ARRAY:
name = ".init_array";
goto get_vma;
case DT_FINI_ARRAY:
name = ".fini_array";
goto get_vma;
case DT_HASH:
name = ".hash";
goto get_vma;
case DT_STRTAB:
name = ".dynstr";
goto get_vma;
case DT_SYMTAB:
name = ".dynsym";
goto get_vma;
case DT_VERDEF:
name = ".gnu.version_d";
goto get_vma;
case DT_VERNEED:
name = ".gnu.version_r";
goto get_vma;
case DT_VERSYM:
name = ".gnu.version";
get_vma:
o = bfd_get_section_by_name (abfd, name);
if (o == NULL)
{
(*_bfd_error_handler)
(_("%s: could not find output section %s"),
bfd_get_filename (abfd), name);
goto error_return;
}
dyn.d_un.d_ptr = o->vma;
break;
case DT_REL:
case DT_RELA:
case DT_RELSZ:
case DT_RELASZ:
if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
type = SHT_REL;
else
type = SHT_RELA;
dyn.d_un.d_val = 0;
for (i = 1; i < elf_numsections (abfd); i++)
{
Elf_Internal_Shdr *hdr;
hdr = elf_elfsections (abfd)[i];
if (hdr->sh_type == type
&& (hdr->sh_flags & SHF_ALLOC) != 0)
{
if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
dyn.d_un.d_val += hdr->sh_size;
else
{
if (dyn.d_un.d_val == 0
|| hdr->sh_addr < dyn.d_un.d_val)
dyn.d_un.d_val = hdr->sh_addr;
}
}
}
break;
}
bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
}
}
/* If we have created any dynamic sections, then output them. */
if (dynobj != NULL)
{
if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
goto error_return;
for (o = dynobj->sections; o != NULL; o = o->next)
{
if ((o->flags & SEC_HAS_CONTENTS) == 0
|| o->_raw_size == 0
|| o->output_section == bfd_abs_section_ptr)
continue;
if ((o->flags & SEC_LINKER_CREATED) == 0)
{
/* At this point, we are only interested in sections
created by _bfd_elf_link_create_dynamic_sections. */
continue;
}
if ((elf_section_data (o->output_section)->this_hdr.sh_type
!= SHT_STRTAB)
|| strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
{
if (! bfd_set_section_contents (abfd, o->output_section,
o->contents,
(file_ptr) o->output_offset,
o->_raw_size))
goto error_return;
}
else
{
/* The contents of the .dynstr section are actually in a
stringtab. */
off = elf_section_data (o->output_section)->this_hdr.sh_offset;
if (bfd_seek (abfd, off, SEEK_SET) != 0
|| ! _bfd_elf_strtab_emit (abfd,
elf_hash_table (info)->dynstr))
goto error_return;
}
}
}
if (info->relocatable)
{
bfd_boolean failed = FALSE;
bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
if (failed)
goto error_return;
}
/* If we have optimized stabs strings, output them. */
if (elf_hash_table (info)->stab_info != NULL)
{
if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
goto error_return;
}
if (info->eh_frame_hdr)
{
if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
goto error_return;
}
if (finfo.symstrtab != NULL)
_bfd_stringtab_free (finfo.symstrtab);
if (finfo.contents != NULL)
free (finfo.contents);
if (finfo.external_relocs != NULL)
free (finfo.external_relocs);
if (finfo.internal_relocs != NULL)
free (finfo.internal_relocs);
if (finfo.external_syms != NULL)
free (finfo.external_syms);
if (finfo.locsym_shndx != NULL)
free (finfo.locsym_shndx);
if (finfo.internal_syms != NULL)
free (finfo.internal_syms);
if (finfo.indices != NULL)
free (finfo.indices);
if (finfo.sections != NULL)
free (finfo.sections);
if (finfo.symbuf != NULL)
free (finfo.symbuf);
if (finfo.symshndxbuf != NULL)
free (finfo.symshndxbuf);
for (o = abfd->sections; o != NULL; o = o->next)
{
if ((o->flags & SEC_RELOC) != 0
&& elf_section_data (o)->rel_hashes != NULL)
free (elf_section_data (o)->rel_hashes);
}
elf_tdata (abfd)->linker = TRUE;
return TRUE;
error_return:
if (finfo.symstrtab != NULL)
_bfd_stringtab_free (finfo.symstrtab);
if (finfo.contents != NULL)
free (finfo.contents);
if (finfo.external_relocs != NULL)
free (finfo.external_relocs);
if (finfo.internal_relocs != NULL)
free (finfo.internal_relocs);
if (finfo.external_syms != NULL)
free (finfo.external_syms);
if (finfo.locsym_shndx != NULL)
free (finfo.locsym_shndx);
if (finfo.internal_syms != NULL)
free (finfo.internal_syms);
if (finfo.indices != NULL)
free (finfo.indices);
if (finfo.sections != NULL)
free (finfo.sections);
if (finfo.symbuf != NULL)
free (finfo.symbuf);
if (finfo.symshndxbuf != NULL)
free (finfo.symshndxbuf);
for (o = abfd->sections; o != NULL; o = o->next)
{
if ((o->flags & SEC_RELOC) != 0
&& elf_section_data (o)->rel_hashes != NULL)
free (elf_section_data (o)->rel_hashes);
}
return FALSE;
}
/* Add a symbol to the output symbol table. */
static bfd_boolean
elf_link_output_sym (struct elf_final_link_info *finfo,
const char *name,
Elf_Internal_Sym *elfsym,
asection *input_sec,
struct elf_link_hash_entry *h)
{
bfd_byte *dest;
Elf_External_Sym_Shndx *destshndx;
bfd_boolean (*output_symbol_hook)
(struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
struct elf_link_hash_entry *);
const struct elf_backend_data *bed;
bed = get_elf_backend_data (finfo->output_bfd);
output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
if (output_symbol_hook != NULL)
{
if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
return FALSE;
}
if (name == NULL || *name == '\0')
elfsym->st_name = 0;
else if (input_sec->flags & SEC_EXCLUDE)
elfsym->st_name = 0;
else
{
elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
name, TRUE, FALSE);
if (elfsym->st_name == (unsigned long) -1)
return FALSE;
}
if (finfo->symbuf_count >= finfo->symbuf_size)
{
if (! elf_link_flush_output_syms (finfo, bed))
return FALSE;
}
dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
destshndx = finfo->symshndxbuf;
if (destshndx != NULL)
{
if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
{
bfd_size_type amt;
amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
if (destshndx == NULL)
return FALSE;
memset ((char *) destshndx + amt, 0, amt);
finfo->shndxbuf_size *= 2;
}
destshndx += bfd_get_symcount (finfo->output_bfd);
}
bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
finfo->symbuf_count += 1;
bfd_get_symcount (finfo->output_bfd) += 1;
return TRUE;
}
/* Flush the output symbols to the file. */
static bfd_boolean
elf_link_flush_output_syms (struct elf_final_link_info *finfo,
const struct elf_backend_data *bed)
{
if (finfo->symbuf_count > 0)
{
Elf_Internal_Shdr *hdr;
file_ptr pos;
bfd_size_type amt;
hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
pos = hdr->sh_offset + hdr->sh_size;
amt = finfo->symbuf_count * bed->s->sizeof_sym;
if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
|| bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
return FALSE;
hdr->sh_size += amt;
finfo->symbuf_count = 0;
}
return TRUE;
}
/* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
allowing an unsatisfied unversioned symbol in the DSO to match a
versioned symbol that would normally require an explicit version.
We also handle the case that a DSO references a hidden symbol
which may be satisfied by a versioned symbol in another DSO. */
static bfd_boolean
elf_link_check_versioned_symbol (struct bfd_link_info *info,
const struct elf_backend_data *bed,
struct elf_link_hash_entry *h)
{
bfd *abfd;
struct elf_link_loaded_list *loaded;
if (!is_elf_hash_table (info->hash))
return FALSE;
switch (h->root.type)
{
default:
abfd = NULL;
break;
case bfd_link_hash_undefined:
case bfd_link_hash_undefweak:
abfd = h->root.u.undef.abfd;
if ((abfd->flags & DYNAMIC) == 0
|| elf_dyn_lib_class (abfd) != DYN_DT_NEEDED)
return FALSE;
break;
case bfd_link_hash_defined:
case bfd_link_hash_defweak:
abfd = h->root.u.def.section->owner;
break;
case bfd_link_hash_common:
abfd = h->root.u.c.p->section->owner;
break;
}
BFD_ASSERT (abfd != NULL);
for (loaded = elf_hash_table (info)->loaded;
loaded != NULL;
loaded = loaded->next)
{
bfd *input;
Elf_Internal_Shdr *hdr;
bfd_size_type symcount;
bfd_size_type extsymcount;
bfd_size_type extsymoff;
Elf_Internal_Shdr *versymhdr;
Elf_Internal_Sym *isym;
Elf_Internal_Sym *isymend;
Elf_Internal_Sym *isymbuf;
Elf_External_Versym *ever;
Elf_External_Versym *extversym;
input = loaded->abfd;
/* We check each DSO for a possible hidden versioned definition. */
if (input == abfd
|| (input->flags & DYNAMIC) == 0
|| elf_dynversym (input) == 0)
continue;
hdr = &elf_tdata (input)->dynsymtab_hdr;
symcount = hdr->sh_size / bed->s->sizeof_sym;
if (elf_bad_symtab (input))
{
extsymcount = symcount;
extsymoff = 0;
}
else
{
extsymcount = symcount - hdr->sh_info;
extsymoff = hdr->sh_info;
}
if (extsymcount == 0)
continue;
isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
NULL, NULL, NULL);
if (isymbuf == NULL)
return FALSE;
/* Read in any version definitions. */
versymhdr = &elf_tdata (input)->dynversym_hdr;
extversym = bfd_malloc (versymhdr->sh_size);
if (extversym == NULL)
goto error_ret;
if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
|| (bfd_bread (extversym, versymhdr->sh_size, input)
!= versymhdr->sh_size))
{
free (extversym);
error_ret:
free (isymbuf);
return FALSE;
}
ever = extversym + extsymoff;
isymend = isymbuf + extsymcount;
for (isym = isymbuf; isym < isymend; isym++, ever++)
{
const char *name;
Elf_Internal_Versym iver;
unsigned short version_index;
if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
|| isym->st_shndx == SHN_UNDEF)
continue;
name = bfd_elf_string_from_elf_section (input,
hdr->sh_link,
isym->st_name);
if (strcmp (name, h->root.root.string) != 0)
continue;
_bfd_elf_swap_versym_in (input, ever, &iver);
if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
{
/* If we have a non-hidden versioned sym, then it should
have provided a definition for the undefined sym. */
abort ();
}
version_index = iver.vs_vers & VERSYM_VERSION;
if (version_index == 1 || version_index == 2)
{
/* This is the base or first version. We can use it. */
free (extversym);
free (isymbuf);
return TRUE;
}
}
free (extversym);
free (isymbuf);
}
return FALSE;
}
/* Add an external symbol to the symbol table. This is called from
the hash table traversal routine. When generating a shared object,
we go through the symbol table twice. The first time we output
anything that might have been forced to local scope in a version
script. The second time we output the symbols that are still
global symbols. */
static bfd_boolean
elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
{
struct elf_outext_info *eoinfo = data;
struct elf_final_link_info *finfo = eoinfo->finfo;
bfd_boolean strip;
Elf_Internal_Sym sym;
asection *input_sec;
const struct elf_backend_data *bed;
if (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_new)
return TRUE;
}
/* Decide whether to output this symbol in this pass. */
if (eoinfo->localsyms)
{
if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
return TRUE;
}
else
{
if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
return TRUE;
}
bed = get_elf_backend_data (finfo->output_bfd);
/* If we have an undefined symbol reference here then it must have
come from a shared library that is being linked in. (Undefined
references in regular files have already been handled). If we
are reporting errors for this situation then do so now. */
if (h->root.type == bfd_link_hash_undefined
&& (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
&& (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
&& ! elf_link_check_versioned_symbol (finfo->info, bed, h)
&& finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
{
if (! ((*finfo->info->callbacks->undefined_symbol)
(finfo->info, h->root.root.string, h->root.u.undef.abfd,
NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
{
eoinfo->failed = TRUE;
return FALSE;
}
}
/* We should also warn if a forced local symbol is referenced from
shared libraries. */
if (! finfo->info->relocatable
&& (! finfo->info->shared)
&& (h->elf_link_hash_flags
& (ELF_LINK_FORCED_LOCAL | ELF_LINK_HASH_REF_DYNAMIC | ELF_LINK_DYNAMIC_DEF | ELF_LINK_DYNAMIC_WEAK))
== (ELF_LINK_FORCED_LOCAL | ELF_LINK_HASH_REF_DYNAMIC)
&& ! elf_link_check_versioned_symbol (finfo->info, bed, h))
{
(*_bfd_error_handler)
(_("%s: %s symbol `%s' in %s is referenced by DSO"),
bfd_get_filename (finfo->output_bfd),
ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
? "internal"
: ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
? "hidden" : "local",
h->root.root.string,
bfd_archive_filename (h->root.u.def.section->owner));
eoinfo->failed = TRUE;
return FALSE;
}
/* We don't want to output symbols that have never been mentioned by
a regular file, or that we have been told to strip. However, if
h->indx is set to -2, the symbol is used by a reloc and we must
output it. */
if (h->indx == -2)
strip = FALSE;
else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
|| (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
&& (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
strip = TRUE;
else if (finfo->info->strip == strip_all)
strip = TRUE;
else if (finfo->info->strip == strip_some
&& bfd_hash_lookup (finfo->info->keep_hash,
h->root.root.string, FALSE, FALSE) == NULL)
strip = TRUE;
else if (finfo->info->strip_discarded
&& (h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak)
&& elf_discarded_section (h->root.u.def.section))
strip = TRUE;
else
strip = FALSE;
/* If we're stripping it, and it's not a dynamic symbol, there's
nothing else to do unless it is a forced local symbol. */
if (strip
&& h->dynindx == -1
&& (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
return TRUE;
sym.st_value = 0;
sym.st_size = h->size;
sym.st_other = h->other;
if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
else if (h->root.type == bfd_link_hash_undefweak
|| h->root.type == bfd_link_hash_defweak)
sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
else
sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
switch (h->root.type)
{
default:
case bfd_link_hash_new:
case bfd_link_hash_warning:
abort ();
return FALSE;
case bfd_link_hash_undefined:
case bfd_link_hash_undefweak:
input_sec = bfd_und_section_ptr;
sym.st_shndx = SHN_UNDEF;
break;
case bfd_link_hash_defined:
case bfd_link_hash_defweak:
{
input_sec = h->root.u.def.section;
if (input_sec->output_section != NULL)
{
sym.st_shndx =
_bfd_elf_section_from_bfd_section (finfo->output_bfd,
input_sec->output_section);
if (sym.st_shndx == SHN_BAD)
{
(*_bfd_error_handler)
(_("%s: could not find output section %s for input section %s"),
bfd_get_filename (finfo->output_bfd),
input_sec->output_section->name,
input_sec->name);
eoinfo->failed = TRUE;
return FALSE;
}
/* ELF symbols in relocatable files are section relative,
but in nonrelocatable files they are virtual
addresses. */
sym.st_value = h->root.u.def.value + input_sec->output_offset;
if (! finfo->info->relocatable)
{
sym.st_value += input_sec->output_section->vma;
if (h->type == STT_TLS)
{
/* STT_TLS symbols are relative to PT_TLS segment
base. */
BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
}
}
}
else
{
BFD_ASSERT (input_sec->owner == NULL
|| (input_sec->owner->flags & DYNAMIC) != 0);
sym.st_shndx = SHN_UNDEF;
input_sec = bfd_und_section_ptr;
}
}
break;
case bfd_link_hash_common:
input_sec = h->root.u.c.p->section;
sym.st_shndx = SHN_COMMON;
sym.st_value = 1 << h->root.u.c.p->alignment_power;
break;
case bfd_link_hash_indirect:
/* These symbols are created by symbol versioning. They point
to the decorated version of the name. For example, if the
symbol foo@@GNU_1.2 is the default, which should be used when
foo is used with no version, then we add an indirect symbol
foo which points to foo@@GNU_1.2. We ignore these symbols,
since the indirected symbol is already in the hash table. */
return TRUE;
}
/* Give the processor backend a chance to tweak the symbol value,
and also to finish up anything that needs to be done for this
symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
forced local syms when non-shared is due to a historical quirk. */
if ((h->dynindx != -1
|| (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
&& ((finfo->info->shared
&& (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
|| h->root.type != bfd_link_hash_undefweak))
|| (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
&& elf_hash_table (finfo->info)->dynamic_sections_created)
{
if (! ((*bed->elf_backend_finish_dynamic_symbol)
(finfo->output_bfd, finfo->info, h, &sym)))
{
eoinfo->failed = TRUE;
return FALSE;
}
}
/* If we are marking the symbol as undefined, and there are no
non-weak references to this symbol from a regular object, then
mark the symbol as weak undefined; if there are non-weak
references, mark the symbol as strong. We can't do this earlier,
because it might not be marked as undefined until the
finish_dynamic_symbol routine gets through with it. */
if (sym.st_shndx == SHN_UNDEF
&& (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
&& (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
|| ELF_ST_BIND (sym.st_info) == STB_WEAK))
{
int bindtype;
if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
bindtype = STB_GLOBAL;
else
bindtype = STB_WEAK;
sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
}
/* If a non-weak symbol with non-default visibility is not defined
locally, it is a fatal error. */
if (! finfo->info->relocatable
&& ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
&& ELF_ST_BIND (sym.st_info) != STB_WEAK
&& h->root.type == bfd_link_hash_undefined
&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
{
(*_bfd_error_handler)
(_("%s: %s symbol `%s' isn't defined"),
bfd_get_filename (finfo->output_bfd),
ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
? "protected"
: ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
? "internal" : "hidden",
h->root.root.string);
eoinfo->failed = TRUE;
return FALSE;
}
/* If this symbol should be put in the .dynsym section, then put it
there now. We already know the symbol index. We also fill in
the entry in the .hash section. */
if (h->dynindx != -1
&& elf_hash_table (finfo->info)->dynamic_sections_created)
{
size_t bucketcount;
size_t bucket;
size_t hash_entry_size;
bfd_byte *bucketpos;
bfd_vma chain;
bfd_byte *esym;
sym.st_name = h->dynstr_index;
esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
bucketcount = elf_hash_table (finfo->info)->bucketcount;
bucket = h->elf_hash_value % bucketcount;
hash_entry_size
= elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
bucketpos = ((bfd_byte *) finfo->hash_sec->contents
+ (bucket + 2) * hash_entry_size);
chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
((bfd_byte *) finfo->hash_sec->contents
+ (bucketcount + 2 + h->dynindx) * hash_entry_size));
if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
{
Elf_Internal_Versym iversym;
Elf_External_Versym *eversym;
if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
{
if (h->verinfo.verdef == NULL)
iversym.vs_vers = 0;
else
iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
}
else
{
if (h->verinfo.vertree == NULL)
iversym.vs_vers = 1;
else
iversym.vs_vers = h->verinfo.vertree->vernum + 1;
}
if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
iversym.vs_vers |= VERSYM_HIDDEN;
eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
eversym += h->dynindx;
_bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
}
}
/* If we're stripping it, then it was just a dynamic symbol, and
there's nothing else to do. */
if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
return TRUE;
h->indx = bfd_get_symcount (finfo->output_bfd);
if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
{
eoinfo->failed = TRUE;
return FALSE;
}
return TRUE;
}
/* Link an input file into the linker output file. This function
handles all the sections and relocations of the input file at once.
This is so that we only have to read the local symbols once, and
don't have to keep them in memory. */
static bfd_boolean
elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
{
bfd_boolean (*relocate_section)
(bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
bfd *output_bfd;
Elf_Internal_Shdr *symtab_hdr;
size_t locsymcount;
size_t extsymoff;
Elf_Internal_Sym *isymbuf;
Elf_Internal_Sym *isym;
Elf_Internal_Sym *isymend;
long *pindex;
asection **ppsection;
asection *o;
const struct elf_backend_data *bed;
bfd_boolean emit_relocs;
struct elf_link_hash_entry **sym_hashes;
output_bfd = finfo->output_bfd;
bed = get_elf_backend_data (output_bfd);
relocate_section = bed->elf_backend_relocate_section;
/* If this is a dynamic object, we don't want to do anything here:
we don't want the local symbols, and we don't want the section
contents. */
if ((input_bfd->flags & DYNAMIC) != 0)
return TRUE;
emit_relocs = (finfo->info->relocatable
|| finfo->info->emitrelocations
|| bed->elf_backend_emit_relocs);
symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
if (elf_bad_symtab (input_bfd))
{
locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
extsymoff = 0;
}
else
{
locsymcount = symtab_hdr->sh_info;
extsymoff = symtab_hdr->sh_info;
}
/* Read the local symbols. */
isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
if (isymbuf == NULL && locsymcount != 0)
{
isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
finfo->internal_syms,
finfo->external_syms,
finfo->locsym_shndx);
if (isymbuf == NULL)
return FALSE;
}
/* Find local symbol sections and adjust values of symbols in
SEC_MERGE sections. Write out those local symbols we know are
going into the output file. */
isymend = isymbuf + locsymcount;
for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
isym < isymend;
isym++, pindex++, ppsection++)
{
asection *isec;
const char *name;
Elf_Internal_Sym osym;
*pindex = -1;
if (elf_bad_symtab (input_bfd))
{
if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
{
*ppsection = NULL;
continue;
}
}
if (isym->st_shndx == SHN_UNDEF)
isec = bfd_und_section_ptr;
else if (isym->st_shndx < SHN_LORESERVE
|| isym->st_shndx > SHN_HIRESERVE)
{
isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
if (isec
&& isec->sec_info_type == ELF_INFO_TYPE_MERGE
&& ELF_ST_TYPE (isym->st_info) != STT_SECTION)
isym->st_value =
_bfd_merged_section_offset (output_bfd, &isec,
elf_section_data (isec)->sec_info,
isym->st_value, 0);
}
else if (isym->st_shndx == SHN_ABS)
isec = bfd_abs_section_ptr;
else if (isym->st_shndx == SHN_COMMON)
isec = bfd_com_section_ptr;
else
{
/* Who knows? */
isec = NULL;
}
*ppsection = isec;
/* Don't output the first, undefined, symbol. */
if (ppsection == finfo->sections)
continue;
if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
{
/* We never output section symbols. Instead, we use the
section symbol of the corresponding section in the output
file. */
continue;
}
/* If we are stripping all symbols, we don't want to output this
one. */
if (finfo->info->strip == strip_all)
continue;
/* If we are discarding all local symbols, we don't want to
output this one. If we are generating a relocatable output
file, then some of the local symbols may be required by
relocs; we output them below as we discover that they are
needed. */
if (finfo->info->discard == discard_all)
continue;
/* If this symbol is defined in a section which we are
discarding, we don't need to keep it, but note that
linker_mark is only reliable for sections that have contents.
For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
as well as linker_mark. */
if ((isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
&& isec != NULL
&& ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
|| (! finfo->info->relocatable
&& (isec->flags & SEC_EXCLUDE) != 0)))
continue;
/* Get the name of the symbol. */
name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
isym->st_name);
if (name == NULL)
return FALSE;
/* See if we are discarding symbols with this name. */
if ((finfo->info->strip == strip_some
&& (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
== NULL))
|| (((finfo->info->discard == discard_sec_merge
&& (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
|| finfo->info->discard == discard_l)
&& bfd_is_local_label_name (input_bfd, name)))
continue;
/* If we get here, we are going to output this symbol. */
osym = *isym;
/* Adjust the section index for the output file. */
osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
isec->output_section);
if (osym.st_shndx == SHN_BAD)
return FALSE;
*pindex = bfd_get_symcount (output_bfd);
/* ELF symbols in relocatable files are section relative, but
in executable files they are virtual addresses. Note that
this code assumes that all ELF sections have an associated
BFD section with a reasonable value for output_offset; below
we assume that they also have a reasonable value for
output_section. Any special sections must be set up to meet
these requirements. */
osym.st_value += isec->output_offset;
if (! finfo->info->relocatable)
{
osym.st_value += isec->output_section->vma;
if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
{
/* STT_TLS symbols are relative to PT_TLS segment base. */
BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
}
}
if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
return FALSE;
}
/* Relocate the contents of each section. */
sym_hashes = elf_sym_hashes (input_bfd);
for (o = input_bfd->sections; o != NULL; o = o->next)
{
bfd_byte *contents;
if (! o->linker_mark)
{
/* This section was omitted from the link. */
continue;
}
if ((o->flags & SEC_HAS_CONTENTS) == 0
|| (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
continue;
if ((o->flags & SEC_LINKER_CREATED) != 0)
{
/* Section was created by _bfd_elf_link_create_dynamic_sections
or somesuch. */
continue;
}
/* Get the contents of the section. They have been cached by a
relaxation routine. Note that o is a section in an input
file, so the contents field will not have been set by any of
the routines which work on output files. */
if (elf_section_data (o)->this_hdr.contents != NULL)
contents = elf_section_data (o)->this_hdr.contents;
else
{
contents = finfo->contents;
if (! bfd_get_section_contents (input_bfd, o, contents, 0,
o->_raw_size))
return FALSE;
}
if ((o->flags & SEC_RELOC) != 0)
{
Elf_Internal_Rela *internal_relocs;
bfd_vma r_type_mask;
int r_sym_shift;
/* Get the swapped relocs. */
internal_relocs
= _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
finfo->internal_relocs, FALSE);
if (internal_relocs == NULL
&& o->reloc_count > 0)
return FALSE;
if (bed->s->arch_size == 32)
{
r_type_mask = 0xff;
r_sym_shift = 8;
}
else
{
r_type_mask = 0xffffffff;
r_sym_shift = 32;
}
/* Run through the relocs looking for any against symbols
from discarded sections and section symbols from
removed link-once sections. Complain about relocs
against discarded sections. Zero relocs against removed
link-once sections. Preserve debug information as much
as we can. */
if (!elf_section_ignore_discarded_relocs (o))
{
Elf_Internal_Rela *rel, *relend;
rel = internal_relocs;
relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
for ( ; rel < relend; rel++)
{
unsigned long r_symndx = rel->r_info >> r_sym_shift;
asection *sec;
if (r_symndx >= locsymcount
|| (elf_bad_symtab (input_bfd)
&& finfo->sections[r_symndx] == NULL))
{
struct elf_link_hash_entry *h;
h = sym_hashes[r_symndx - extsymoff];
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;
/* Complain if the definition comes from a
discarded section. */
sec = h->root.u.def.section;
if ((h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak)
&& elf_discarded_section (sec))
{
if ((o->flags & SEC_DEBUGGING) != 0)
{
BFD_ASSERT (r_symndx != 0);
/* Try to preserve debug information. */
if ((o->flags & SEC_DEBUGGING) != 0
&& sec->kept_section != NULL
&& sec->_raw_size == sec->kept_section->_raw_size)
h->root.u.def.section
= sec->kept_section;
else
memset (rel, 0, sizeof (*rel));
}
else
finfo->info->callbacks->error_handler
(LD_DEFINITION_IN_DISCARDED_SECTION,
_("%T: discarded in section `%s' from %s\n"),
h->root.root.string,
h->root.root.string,
h->root.u.def.section->name,
bfd_archive_filename (h->root.u.def.section->owner));
}
}
else
{
sec = finfo->sections[r_symndx];
if (sec != NULL && elf_discarded_section (sec))
{
if ((o->flags & SEC_DEBUGGING) != 0
|| (sec->flags & SEC_LINK_ONCE) != 0)
{
BFD_ASSERT (r_symndx != 0);
/* Try to preserve debug information. */
if ((o->flags & SEC_DEBUGGING) != 0
&& sec->kept_section != NULL
&& sec->_raw_size == sec->kept_section->_raw_size)
finfo->sections[r_symndx]
= sec->kept_section;
else
{
rel->r_info &= r_type_mask;
rel->r_addend = 0;
}
}
else
{
static int count;
int ok;
char *buf;
ok = asprintf (&buf, "local symbol %d",
count++);
if (ok <= 0)
buf = (char *) "local symbol";
finfo->info->callbacks->error_handler
(LD_DEFINITION_IN_DISCARDED_SECTION,
_("%T: discarded in section `%s' from %s\n"),
buf, buf, sec->name,
bfd_archive_filename (input_bfd));
if (ok != -1)
free (buf);
}
}
}
}
}
/* Relocate the section by invoking a back end routine.
The back end routine is responsible for adjusting the
section contents as necessary, and (if using Rela relocs
and generating a relocatable output file) adjusting the
reloc addend as necessary.
The back end routine does not have to worry about setting
the reloc address or the reloc symbol index.
The back end routine is given a pointer to the swapped in
internal symbols, and can access the hash table entries
for the external symbols via elf_sym_hashes (input_bfd).
When generating relocatable output, the back end routine
must handle STB_LOCAL/STT_SECTION symbols specially. The
output symbol is going to be a section symbol
corresponding to the output section, which will require
the addend to be adjusted. */
if (! (*relocate_section) (output_bfd, finfo->info,
input_bfd, o, contents,
internal_relocs,
isymbuf,
finfo->sections))
return FALSE;
if (emit_relocs)
{
Elf_Internal_Rela *irela;
Elf_Internal_Rela *irelaend;
bfd_vma last_offset;
struct elf_link_hash_entry **rel_hash;
Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
unsigned int next_erel;
bfd_boolean (*reloc_emitter)
(bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *);
bfd_boolean rela_normal;
input_rel_hdr = &elf_section_data (o)->rel_hdr;
rela_normal = (bed->rela_normal
&& (input_rel_hdr->sh_entsize
== bed->s->sizeof_rela));
/* Adjust the reloc addresses and symbol indices. */
irela = internal_relocs;
irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
rel_hash = (elf_section_data (o->output_section)->rel_hashes
+ elf_section_data (o->output_section)->rel_count
+ elf_section_data (o->output_section)->rel_count2);
last_offset = o->output_offset;
if (!finfo->info->relocatable)
last_offset += o->output_section->vma;
for (next_erel = 0; irela < irelaend; irela++, next_erel++)
{
unsigned long r_symndx;
asection *sec;
Elf_Internal_Sym sym;
if (next_erel == bed->s->int_rels_per_ext_rel)
{
rel_hash++;
next_erel = 0;
}
irela->r_offset = _bfd_elf_section_offset (output_bfd,
finfo->info, o,
irela->r_offset);
if (irela->r_offset >= (bfd_vma) -2)
{
/* This is a reloc for a deleted entry or somesuch.
Turn it into an R_*_NONE reloc, at the same
offset as the last reloc. elf_eh_frame.c and
elf_bfd_discard_info rely on reloc offsets
being ordered. */
irela->r_offset = last_offset;
irela->r_info = 0;
irela->r_addend = 0;
continue;
}
irela->r_offset += o->output_offset;
/* Relocs in an executable have to be virtual addresses. */
if (!finfo->info->relocatable)
irela->r_offset += o->output_section->vma;
last_offset = irela->r_offset;
r_symndx = irela->r_info >> r_sym_shift;
if (r_symndx == STN_UNDEF)
continue;
if (r_symndx >= locsymcount
|| (elf_bad_symtab (input_bfd)
&& finfo->sections[r_symndx] == NULL))
{
struct elf_link_hash_entry *rh;
unsigned long indx;
/* This is a reloc against a global symbol. We
have not yet output all the local symbols, so
we do not know the symbol index of any global
symbol. We set the rel_hash entry for this
reloc to point to the global hash table entry
for this symbol. The symbol index is then
set at the end of elf_bfd_final_link. */
indx = r_symndx - extsymoff;
rh = elf_sym_hashes (input_bfd)[indx];
while (rh->root.type == bfd_link_hash_indirect
|| rh->root.type == bfd_link_hash_warning)
rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
/* Setting the index to -2 tells
elf_link_output_extsym that this symbol is
used by a reloc. */
BFD_ASSERT (rh->indx < 0);
rh->indx = -2;
*rel_hash = rh;
continue;
}
/* This is a reloc against a local symbol. */
*rel_hash = NULL;
sym = isymbuf[r_symndx];
sec = finfo->sections[r_symndx];
if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
{
/* I suppose the backend ought to fill in the
section of any STT_SECTION symbol against a
processor specific section. If we have
discarded a section, the output_section will
be the absolute section. */
if (bfd_is_abs_section (sec)
|| (sec != NULL
&& bfd_is_abs_section (sec->output_section)))
r_symndx = 0;
else if (sec == NULL || sec->owner == NULL)
{
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
else
{
r_symndx = sec->output_section->target_index;
BFD_ASSERT (r_symndx != 0);
}
/* Adjust the addend according to where the
section winds up in the output section. */
if (rela_normal)
irela->r_addend += sec->output_offset;
}
else
{
if (finfo->indices[r_symndx] == -1)
{
unsigned long shlink;
const char *name;
asection *osec;
if (finfo->info->strip == strip_all)
{
/* You can't do ld -r -s. */
bfd_set_error (bfd_error_invalid_operation);
return FALSE;
}
/* This symbol was skipped earlier, but
since it is needed by a reloc, we
must output it now. */
shlink = symtab_hdr->sh_link;
name = (bfd_elf_string_from_elf_section
(input_bfd, shlink, sym.st_name));
if (name == NULL)
return FALSE;
osec = sec->output_section;
sym.st_shndx =
_bfd_elf_section_from_bfd_section (output_bfd,
osec);
if (sym.st_shndx == SHN_BAD)
return FALSE;
sym.st_value += sec->output_offset;
if (! finfo->info->relocatable)
{
sym.st_value += osec->vma;
if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
{
/* STT_TLS symbols are relative to PT_TLS
segment base. */
BFD_ASSERT (elf_hash_table (finfo->info)
->tls_sec != NULL);
sym.st_value -= (elf_hash_table (finfo->info)
->tls_sec->vma);
}
}
finfo->indices[r_symndx]
= bfd_get_symcount (output_bfd);
if (! elf_link_output_sym (finfo, name, &sym, sec,
NULL))
return FALSE;
}
r_symndx = finfo->indices[r_symndx];
}
irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
| (irela->r_info & r_type_mask));
}
/* Swap out the relocs. */
if (bed->elf_backend_emit_relocs
&& !(finfo->info->relocatable
|| finfo->info->emitrelocations))
reloc_emitter = bed->elf_backend_emit_relocs;
else
reloc_emitter = _bfd_elf_link_output_relocs;
if (input_rel_hdr->sh_size != 0
&& ! (*reloc_emitter) (output_bfd, o, input_rel_hdr,
internal_relocs))
return FALSE;
input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
{
internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
* bed->s->int_rels_per_ext_rel);
if (! (*reloc_emitter) (output_bfd, o, input_rel_hdr2,
internal_relocs))
return FALSE;
}
}
}
/* Write out the modified section contents. */
if (bed->elf_backend_write_section
&& (*bed->elf_backend_write_section) (output_bfd, o, contents))
{
/* Section written out. */
}
else switch (o->sec_info_type)
{
case ELF_INFO_TYPE_STABS:
if (! (_bfd_write_section_stabs
(output_bfd,
&elf_hash_table (finfo->info)->stab_info,
o, &elf_section_data (o)->sec_info, contents)))
return FALSE;
break;
case ELF_INFO_TYPE_MERGE:
if (! _bfd_write_merged_section (output_bfd, o,
elf_section_data (o)->sec_info))
return FALSE;
break;
case ELF_INFO_TYPE_EH_FRAME:
{
if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
o, contents))
return FALSE;
}
break;
default:
{
bfd_size_type sec_size;
sec_size = (o->_cooked_size != 0 ? o->_cooked_size : o->_raw_size);
if (! (o->flags & SEC_EXCLUDE)
&& ! bfd_set_section_contents (output_bfd, o->output_section,
contents,
(file_ptr) o->output_offset,
sec_size))
return FALSE;
}
break;
}
}
return TRUE;
}
/* Generate a reloc when linking an ELF file. This is a reloc
requested by the linker, and does come from any input file. This
is used to build constructor and destructor tables when linking
with -Ur. */
static bfd_boolean
elf_reloc_link_order (bfd *output_bfd,
struct bfd_link_info *info,
asection *output_section,
struct bfd_link_order *link_order)
{
reloc_howto_type *howto;
long indx;
bfd_vma offset;
bfd_vma addend;
struct elf_link_hash_entry **rel_hash_ptr;
Elf_Internal_Shdr *rel_hdr;
const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
bfd_byte *erel;
unsigned int i;
howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
if (howto == NULL)
{
bfd_set_error (bfd_error_bad_value);
return FALSE;
}
addend = link_order->u.reloc.p->addend;
/* Figure out the symbol index. */
rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
+ elf_section_data (output_section)->rel_count
+ elf_section_data (output_section)->rel_count2);
if (link_order->type == bfd_section_reloc_link_order)
{
indx = link_order->u.reloc.p->u.section->target_index;
BFD_ASSERT (indx != 0);
*rel_hash_ptr = NULL;
}
else
{
struct elf_link_hash_entry *h;
/* Treat a reloc against a defined symbol as though it were
actually against the section. */
h = ((struct elf_link_hash_entry *)
bfd_wrapped_link_hash_lookup (output_bfd, info,
link_order->u.reloc.p->u.name,
FALSE, FALSE, TRUE));
if (h != NULL
&& (h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak))
{
asection *section;
section = h->root.u.def.section;
indx = section->output_section->target_index;
*rel_hash_ptr = NULL;
/* It seems that we ought to add the symbol value to the
addend here, but in practice it has already been added
because it was passed to constructor_callback. */
addend += section->output_section->vma + section->output_offset;
}
else if (h != NULL)
{
/* Setting the index to -2 tells elf_link_output_extsym that
this symbol is used by a reloc. */
h->indx = -2;
*rel_hash_ptr = h;
indx = 0;
}
else
{
if (! ((*info->callbacks->unattached_reloc)
(info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
return FALSE;
indx = 0;
}
}
/* If this is an inplace reloc, we must write the addend into the
object file. */
if (howto->partial_inplace && addend != 0)
{
bfd_size_type size;
bfd_reloc_status_type rstat;
bfd_byte *buf;
bfd_boolean ok;
const char *sym_name;
size = bfd_get_reloc_size (howto);
buf = bfd_zmalloc (size);
if (buf == NULL)
return FALSE;
rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
switch (rstat)
{
case bfd_reloc_ok:
break;
default:
case bfd_reloc_outofrange:
abort ();
case bfd_reloc_overflow:
if (link_order->type == bfd_section_reloc_link_order)
sym_name = bfd_section_name (output_bfd,
link_order->u.reloc.p->u.section);
else
sym_name = link_order->u.reloc.p->u.name;
if (! ((*info->callbacks->reloc_overflow)
(info, sym_name, howto->name, addend, NULL, NULL, 0)))
{
free (buf);
return FALSE;
}
break;
}
ok = bfd_set_section_contents (output_bfd, output_section, buf,
link_order->offset, size);
free (buf);
if (! ok)
return FALSE;
}
/* The address of a reloc is relative to the section in a
relocatable file, and is a virtual address in an executable
file. */
offset = link_order->offset;
if (! info->relocatable)
offset += output_section->vma;
for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
{
irel[i].r_offset = offset;
irel[i].r_info = 0;
irel[i].r_addend = 0;
}
if (bed->s->arch_size == 32)
irel[0].r_info = ELF32_R_INFO (indx, howto->type);
else
irel[0].r_info = ELF64_R_INFO (indx, howto->type);
rel_hdr = &elf_section_data (output_section)->rel_hdr;
erel = rel_hdr->contents;
if (rel_hdr->sh_type == SHT_REL)
{
erel += (elf_section_data (output_section)->rel_count
* bed->s->sizeof_rel);
(*bed->s->swap_reloc_out) (output_bfd, irel, erel);
}
else
{
irel[0].r_addend = addend;
erel += (elf_section_data (output_section)->rel_count
* bed->s->sizeof_rela);
(*bed->s->swap_reloca_out) (output_bfd, irel, erel);
}
++elf_section_data (output_section)->rel_count;
return TRUE;
}
/* Garbage collect unused sections. */
static bfd_boolean elf_gc_sweep_symbol
(struct elf_link_hash_entry *, void *);
static bfd_boolean elf_gc_allocate_got_offsets
(struct elf_link_hash_entry *, void *);
/* The mark phase of garbage collection. For a given section, mark
it and any sections in this section's group, and all the sections
which define symbols to which it refers. */
typedef asection * (*gc_mark_hook_fn)
(asection *, struct bfd_link_info *, Elf_Internal_Rela *,
struct elf_link_hash_entry *, Elf_Internal_Sym *);
static bfd_boolean
elf_gc_mark (struct bfd_link_info *info,
asection *sec,
gc_mark_hook_fn gc_mark_hook)
{
bfd_boolean ret;
asection *group_sec;
sec->gc_mark = 1;
/* Mark all the sections in the group. */
group_sec = elf_section_data (sec)->next_in_group;
if (group_sec && !group_sec->gc_mark)
if (!elf_gc_mark (info, group_sec, gc_mark_hook))
return FALSE;
/* Look through the section relocs. */
ret = TRUE;
if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
{
Elf_Internal_Rela *relstart, *rel, *relend;
Elf_Internal_Shdr *symtab_hdr;
struct elf_link_hash_entry **sym_hashes;
size_t nlocsyms;
size_t extsymoff;
bfd *input_bfd = sec->owner;
const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
Elf_Internal_Sym *isym = NULL;
int r_sym_shift;
symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
sym_hashes = elf_sym_hashes (input_bfd);
/* Read the local symbols. */
if (elf_bad_symtab (input_bfd))
{
nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
extsymoff = 0;
}
else
extsymoff = nlocsyms = symtab_hdr->sh_info;
isym = (Elf_Internal_Sym *) symtab_hdr->contents;
if (isym == NULL && nlocsyms != 0)
{
isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
NULL, NULL, NULL);
if (isym == NULL)
return FALSE;
}
/* Read the relocations. */
relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
info->keep_memory);
if (relstart == NULL)
{
ret = FALSE;
goto out1;
}
relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
if (bed->s->arch_size == 32)
r_sym_shift = 8;
else
r_sym_shift = 32;
for (rel = relstart; rel < relend; rel++)
{
unsigned long r_symndx;
asection *rsec;
struct elf_link_hash_entry *h;
r_symndx = rel->r_info >> r_sym_shift;
if (r_symndx == 0)
continue;
if (r_symndx >= nlocsyms
|| ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
{
h = sym_hashes[r_symndx - extsymoff];
rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
}
else
{
rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
}
if (rsec && !rsec->gc_mark)
{
if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
rsec->gc_mark = 1;
else if (!elf_gc_mark (info, rsec, gc_mark_hook))
{
ret = FALSE;
goto out2;
}
}
}
out2:
if (elf_section_data (sec)->relocs != relstart)
free (relstart);
out1:
if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
{
if (! info->keep_memory)
free (isym);
else
symtab_hdr->contents = (unsigned char *) isym;
}
}
return ret;
}
/* The sweep phase of garbage collection. Remove all garbage sections. */
typedef bfd_boolean (*gc_sweep_hook_fn)
(bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
static bfd_boolean
elf_gc_sweep (struct bfd_link_info *info, gc_sweep_hook_fn gc_sweep_hook)
{
bfd *sub;
for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
{
asection *o;
if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
continue;
for (o = sub->sections; o != NULL; o = o->next)
{
/* Keep special sections. Keep .debug sections. */
if ((o->flags & SEC_LINKER_CREATED)
|| (o->flags & SEC_DEBUGGING))
o->gc_mark = 1;
if (o->gc_mark)
continue;
/* Skip sweeping sections already excluded. */
if (o->flags & SEC_EXCLUDE)
continue;
/* Since this is early in the link process, it is simple
to remove a section from the output. */
o->flags |= SEC_EXCLUDE;
/* But we also have to update some of the relocation
info we collected before. */
if (gc_sweep_hook
&& (o->flags & SEC_RELOC) && o->reloc_count > 0)
{
Elf_Internal_Rela *internal_relocs;
bfd_boolean r;
internal_relocs
= _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
info->keep_memory);
if (internal_relocs == NULL)
return FALSE;
r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
if (elf_section_data (o)->relocs != internal_relocs)
free (internal_relocs);
if (!r)
return FALSE;
}
}
}
/* Remove the symbols that were in the swept sections from the dynamic
symbol table. GCFIXME: Anyone know how to get them out of the
static symbol table as well? */
{
int i = 0;
elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol, &i);
elf_hash_table (info)->dynsymcount = i;
}
return TRUE;
}
/* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
static bfd_boolean
elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *idxptr)
{
int *idx = idxptr;
if (h->root.type == bfd_link_hash_warning)
h = (struct elf_link_hash_entry *) h->root.u.i.link;
if (h->dynindx != -1
&& ((h->root.type != bfd_link_hash_defined
&& h->root.type != bfd_link_hash_defweak)
|| h->root.u.def.section->gc_mark))
h->dynindx = (*idx)++;
return TRUE;
}
/* Propagate collected vtable information. This is called through
elf_link_hash_traverse. */
static bfd_boolean
elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
{
if (h->root.type == bfd_link_hash_warning)
h = (struct elf_link_hash_entry *) h->root.u.i.link;
/* Those that are not vtables. */
if (h->vtable_parent == NULL)
return TRUE;
/* Those vtables that do not have parents, we cannot merge. */
if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
return TRUE;
/* If we've already been done, exit. */
if (h->vtable_entries_used && h->vtable_entries_used[-1])
return TRUE;
/* Make sure the parent's table is up to date. */
elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
if (h->vtable_entries_used == NULL)
{
/* None of this table's entries were referenced. Re-use the
parent's table. */
h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
}
else
{
size_t n;
bfd_boolean *cu, *pu;
/* Or the parent's entries into ours. */
cu = h->vtable_entries_used;
cu[-1] = TRUE;
pu = h->vtable_parent->vtable_entries_used;
if (pu != NULL)
{
const struct elf_backend_data *bed;
unsigned int log_file_align;
bed = get_elf_backend_data (h->root.u.def.section->owner);
log_file_align = bed->s->log_file_align;
n = h->vtable_parent->vtable_entries_size >> log_file_align;
while (n--)
{
if (*pu)
*cu = TRUE;
pu++;
cu++;
}
}
}
return TRUE;
}
static bfd_boolean
elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
{
asection *sec;
bfd_vma hstart, hend;
Elf_Internal_Rela *relstart, *relend, *rel;
const struct elf_backend_data *bed;
unsigned int log_file_align;
if (h->root.type == bfd_link_hash_warning)
h = (struct elf_link_hash_entry *) h->root.u.i.link;
/* Take care of both those symbols that do not describe vtables as
well as those that are not loaded. */
if (h->vtable_parent == NULL)
return TRUE;
BFD_ASSERT (h->root.type == bfd_link_hash_defined
|| h->root.type == bfd_link_hash_defweak);
sec = h->root.u.def.section;
hstart = h->root.u.def.value;
hend = hstart + h->size;
relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
if (!relstart)
return *(bfd_boolean *) okp = FALSE;
bed = get_elf_backend_data (sec->owner);
log_file_align = bed->s->log_file_align;
relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
for (rel = relstart; rel < relend; ++rel)
if (rel->r_offset >= hstart && rel->r_offset < hend)
{
/* If the entry is in use, do nothing. */
if (h->vtable_entries_used
&& (rel->r_offset - hstart) < h->vtable_entries_size)
{
bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
if (h->vtable_entries_used[entry])
continue;
}
/* Otherwise, kill it. */
rel->r_offset = rel->r_info = rel->r_addend = 0;
}
return TRUE;
}
/* Do mark and sweep of unused sections. */
bfd_boolean
elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
{
bfd_boolean ok = TRUE;
bfd *sub;
asection * (*gc_mark_hook)
(asection *, struct bfd_link_info *, Elf_Internal_Rela *,
struct elf_link_hash_entry *h, Elf_Internal_Sym *);
if (!get_elf_backend_data (abfd)->can_gc_sections
|| info->relocatable
|| info->emitrelocations
|| !is_elf_hash_table (info->hash)
|| elf_hash_table (info)->dynamic_sections_created)
{
(*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
return TRUE;
}
/* Apply transitive closure to the vtable entry usage info. */
elf_link_hash_traverse (elf_hash_table (info),
elf_gc_propagate_vtable_entries_used,
&ok);
if (!ok)
return FALSE;
/* Kill the vtable relocations that were not used. */
elf_link_hash_traverse (elf_hash_table (info),
elf_gc_smash_unused_vtentry_relocs,
&ok);
if (!ok)
return FALSE;
/* Grovel through relocs to find out who stays ... */
gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
{
asection *o;
if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
continue;
for (o = sub->sections; o != NULL; o = o->next)
{
if (o->flags & SEC_KEEP)
if (!elf_gc_mark (info, o, gc_mark_hook))
return FALSE;
}
}
/* ... and mark SEC_EXCLUDE for those that go. */
if (!elf_gc_sweep (info, get_elf_backend_data (abfd)->gc_sweep_hook))
return FALSE;
return TRUE;
}
/* Called from check_relocs to record the existence of a VTINHERIT reloc. */
bfd_boolean
elf_gc_record_vtinherit (bfd *abfd,
asection *sec,
struct elf_link_hash_entry *h,
bfd_vma offset)
{
struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
struct elf_link_hash_entry **search, *child;
bfd_size_type extsymcount;
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
/* The sh_info field of the symtab header tells us where the
external symbols start. We don't care about the local symbols at
this point. */
extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
if (!elf_bad_symtab (abfd))
extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
sym_hashes = elf_sym_hashes (abfd);
sym_hashes_end = sym_hashes + extsymcount;
/* Hunt down the child symbol, which is in this section at the same
offset as the relocation. */
for (search = sym_hashes; search != sym_hashes_end; ++search)
{
if ((child = *search) != NULL
&& (child->root.type == bfd_link_hash_defined
|| child->root.type == bfd_link_hash_defweak)
&& child->root.u.def.section == sec
&& child->root.u.def.value == offset)
goto win;
}
(*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
bfd_archive_filename (abfd), sec->name,
(unsigned long) offset);
bfd_set_error (bfd_error_invalid_operation);
return FALSE;
win:
if (!h)
{
/* This *should* only be the absolute section. It could potentially
be that someone has defined a non-global vtable though, which
would be bad. It isn't worth paging in the local symbols to be
sure though; that case should simply be handled by the assembler. */
child->vtable_parent = (struct elf_link_hash_entry *) -1;
}
else
child->vtable_parent = h;
return TRUE;
}
/* Called from check_relocs to record the existence of a VTENTRY reloc. */
bfd_boolean
elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
asection *sec ATTRIBUTE_UNUSED,
struct elf_link_hash_entry *h,
bfd_vma addend)
{
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
unsigned int log_file_align = bed->s->log_file_align;
if (addend >= h->vtable_entries_size)
{
size_t size, bytes, file_align;
bfd_boolean *ptr = h->vtable_entries_used;
/* While the symbol is undefined, we have to be prepared to handle
a zero size. */
file_align = 1 << log_file_align;
if (h->root.type == bfd_link_hash_undefined)
size = addend + file_align;
else
{
size = h->size;
if (addend >= size)
{
/* Oops! We've got a reference past the defined end of
the table. This is probably a bug -- shall we warn? */
size = addend + file_align;
}
}
size = (size + file_align - 1) & -file_align;
/* Allocate one extra entry for use as a "done" flag for the
consolidation pass. */
bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
if (ptr)
{
ptr = bfd_realloc (ptr - 1, bytes);
if (ptr != NULL)
{
size_t oldbytes;
oldbytes = (((h->vtable_entries_size >> log_file_align) + 1)
* sizeof (bfd_boolean));
memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
}
}
else
ptr = bfd_zmalloc (bytes);
if (ptr == NULL)
return FALSE;
/* And arrange for that done flag to be at index -1. */
h->vtable_entries_used = ptr + 1;
h->vtable_entries_size = size;
}
h->vtable_entries_used[addend >> log_file_align] = TRUE;
return TRUE;
}
struct alloc_got_off_arg {
bfd_vma gotoff;
unsigned int got_elt_size;
};
/* And an accompanying bit to work out final got entry offsets once
we're done. Should be called from final_link. */
bfd_boolean
elf_gc_common_finalize_got_offsets (bfd *abfd,
struct bfd_link_info *info)
{
bfd *i;
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
bfd_vma gotoff;
unsigned int got_elt_size = bed->s->arch_size / 8;
struct alloc_got_off_arg gofarg;
if (! is_elf_hash_table (info->hash))
return FALSE;
/* The GOT offset is relative to the .got section, but the GOT header is
put into the .got.plt section, if the backend uses it. */
if (bed->want_got_plt)
gotoff = 0;
else
gotoff = bed->got_header_size;
/* Do the local .got entries first. */
for (i = info->input_bfds; i; i = i->link_next)
{
bfd_signed_vma *local_got;
bfd_size_type j, locsymcount;
Elf_Internal_Shdr *symtab_hdr;
if (bfd_get_flavour (i) != bfd_target_elf_flavour)
continue;
local_got = elf_local_got_refcounts (i);
if (!local_got)
continue;
symtab_hdr = &elf_tdata (i)->symtab_hdr;
if (elf_bad_symtab (i))
locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
else
locsymcount = symtab_hdr->sh_info;
for (j = 0; j < locsymcount; ++j)
{
if (local_got[j] > 0)
{
local_got[j] = gotoff;
gotoff += got_elt_size;
}
else
local_got[j] = (bfd_vma) -1;
}
}
/* Then the global .got entries. .plt refcounts are handled by
adjust_dynamic_symbol */
gofarg.gotoff = gotoff;
gofarg.got_elt_size = got_elt_size;
elf_link_hash_traverse (elf_hash_table (info),
elf_gc_allocate_got_offsets,
&gofarg);
return TRUE;
}
/* We need a special top-level link routine to convert got reference counts
to real got offsets. */
static bfd_boolean
elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
{
struct alloc_got_off_arg *gofarg = arg;
if (h->root.type == bfd_link_hash_warning)
h = (struct elf_link_hash_entry *) h->root.u.i.link;
if (h->got.refcount > 0)
{
h->got.offset = gofarg->gotoff;
gofarg->gotoff += gofarg->got_elt_size;
}
else
h->got.offset = (bfd_vma) -1;
return TRUE;
}
/* Many folk need no more in the way of final link than this, once
got entry reference counting is enabled. */
bfd_boolean
elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
{
if (!elf_gc_common_finalize_got_offsets (abfd, info))
return FALSE;
/* Invoke the regular ELF backend linker to do all the work. */
return elf_bfd_final_link (abfd, info);
}
bfd_boolean
elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
{
struct elf_reloc_cookie *rcookie = cookie;
if (rcookie->bad_symtab)
rcookie->rel = rcookie->rels;
for (; rcookie->rel < rcookie->relend; rcookie->rel++)
{
unsigned long r_symndx;
if (! rcookie->bad_symtab)
if (rcookie->rel->r_offset > offset)
return FALSE;
if (rcookie->rel->r_offset != offset)
continue;
r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
if (r_symndx == SHN_UNDEF)
return TRUE;
if (r_symndx >= rcookie->locsymcount
|| ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
{
struct elf_link_hash_entry *h;
h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
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)
&& elf_discarded_section (h->root.u.def.section))
return TRUE;
else
return FALSE;
}
else
{
/* It's not a relocation against a global symbol,
but it could be a relocation against a local
symbol for a discarded section. */
asection *isec;
Elf_Internal_Sym *isym;
/* Need to: get the symbol; get the section. */
isym = &rcookie->locsyms[r_symndx];
if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
{
isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
if (isec != NULL && elf_discarded_section (isec))
return TRUE;
}
}
return FALSE;
}
return FALSE;
}
/* Discard unneeded references to discarded sections.
Returns TRUE if any section's size was changed. */
/* This function assumes that the relocations are in sorted order,
which is true for all known assemblers. */
bfd_boolean
elf_bfd_discard_info (bfd *output_bfd, struct bfd_link_info *info)
{
struct elf_reloc_cookie cookie;
asection *stab, *eh;
Elf_Internal_Shdr *symtab_hdr;
const struct elf_backend_data *bed;
bfd *abfd;
unsigned int count;
bfd_boolean ret = FALSE;
if (info->traditional_format
|| !is_elf_hash_table (info->hash))
return FALSE;
for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
{
if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
continue;
bed = get_elf_backend_data (abfd);
if ((abfd->flags & DYNAMIC) != 0)
continue;
eh = bfd_get_section_by_name (abfd, ".eh_frame");
if (info->relocatable
|| (eh != NULL
&& (eh->_raw_size == 0
|| bfd_is_abs_section (eh->output_section))))
eh = NULL;
stab = bfd_get_section_by_name (abfd, ".stab");
if (stab != NULL
&& (stab->_raw_size == 0
|| bfd_is_abs_section (stab->output_section)
|| stab->sec_info_type != ELF_INFO_TYPE_STABS))
stab = NULL;
if (stab == NULL
&& eh == NULL
&& bed->elf_backend_discard_info == NULL)
continue;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
cookie.abfd = abfd;
cookie.sym_hashes = elf_sym_hashes (abfd);
cookie.bad_symtab = elf_bad_symtab (abfd);
if (cookie.bad_symtab)
{
cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
cookie.extsymoff = 0;
}
else
{
cookie.locsymcount = symtab_hdr->sh_info;
cookie.extsymoff = symtab_hdr->sh_info;
}
if (bed->s->arch_size == 32)
cookie.r_sym_shift = 8;
else
cookie.r_sym_shift = 32;
cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
if (cookie.locsyms == NULL && cookie.locsymcount != 0)
{
cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
cookie.locsymcount, 0,
NULL, NULL, NULL);
if (cookie.locsyms == NULL)
return FALSE;
}
if (stab != NULL)
{
cookie.rels = NULL;
count = stab->reloc_count;
if (count != 0)
cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
info->keep_memory);
if (cookie.rels != NULL)
{
cookie.rel = cookie.rels;
cookie.relend = cookie.rels;
cookie.relend += count * bed->s->int_rels_per_ext_rel;
if (_bfd_discard_section_stabs (abfd, stab,
elf_section_data (stab)->sec_info,
elf_reloc_symbol_deleted_p,
&cookie))
ret = TRUE;
if (elf_section_data (stab)->relocs != cookie.rels)
free (cookie.rels);
}
}
if (eh != NULL)
{
cookie.rels = NULL;
count = eh->reloc_count;
if (count != 0)
cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
info->keep_memory);
cookie.rel = cookie.rels;
cookie.relend = cookie.rels;
if (cookie.rels != NULL)
cookie.relend += count * bed->s->int_rels_per_ext_rel;
if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
elf_reloc_symbol_deleted_p,
&cookie))
ret = TRUE;
if (cookie.rels != NULL
&& elf_section_data (eh)->relocs != cookie.rels)
free (cookie.rels);
}
if (bed->elf_backend_discard_info != NULL
&& (*bed->elf_backend_discard_info) (abfd, &cookie, info))
ret = TRUE;
if (cookie.locsyms != NULL
&& symtab_hdr->contents != (unsigned char *) cookie.locsyms)
{
if (! info->keep_memory)
free (cookie.locsyms);
else
symtab_hdr->contents = (unsigned char *) cookie.locsyms;
}
}
if (info->eh_frame_hdr
&& !info->relocatable
&& _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
ret = TRUE;
return ret;
}
static bfd_boolean
elf_section_ignore_discarded_relocs (asection *sec)
{
const struct elf_backend_data *bed;
switch (sec->sec_info_type)
{
case ELF_INFO_TYPE_STABS:
case ELF_INFO_TYPE_EH_FRAME:
return TRUE;
default:
break;
}
bed = get_elf_backend_data (sec->owner);
if (bed->elf_backend_ignore_discarded_relocs != NULL
&& (*bed->elf_backend_ignore_discarded_relocs) (sec))
return TRUE;
return FALSE;
}
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