bfd_size_type pc_count;
};
+/* Is an undefined weak symbol resolved to 0 ?
+ Reference to an undefined weak symbol is resolved to 0 when
+ building an executable if it isn't dynamic and
+ 1. Has non-GOT/non-PLT relocations in text section.
+ Or
+ 2. Has no GOT/PLT relocation. */
+#define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \
+ ((EH)->elf.root.type == bfd_link_hash_undefweak \
+ && bfd_link_executable (INFO) \
+ && (_bfd_sparc_elf_hash_table (INFO)->interp == NULL \
+ || !(EH)->has_got_reloc \
+ || (EH)->has_non_got_reloc \
+ || !(INFO)->dynamic_undefined_weak))
+
/* SPARC ELF linker hash entry. */
struct _bfd_sparc_elf_link_hash_entry
#define GOT_TLS_GD 2
#define GOT_TLS_IE 3
unsigned char tls_type;
+
+ /* Symbol has GOT or PLT relocations. */
+ unsigned int has_got_reloc : 1;
+
+ /* Symbol has non-GOT/non-PLT relocations in text sections. */
+ unsigned int has_non_got_reloc : 1;
+
};
#define _bfd_sparc_elf_hash_entry(ent) ((struct _bfd_sparc_elf_link_hash_entry *)(ent))
eh = (struct _bfd_sparc_elf_link_hash_entry *) entry;
eh->dyn_relocs = NULL;
eh->tls_type = GOT_UNKNOWN;
+ eh->has_got_reloc = 0;
+ eh->has_non_got_reloc = 0;
}
return entry;
edir->tls_type = eind->tls_type;
eind->tls_type = GOT_UNKNOWN;
}
+
+ /* Copy has_got_reloc and has_non_got_reloc. */
+ edir->has_got_reloc |= eind->has_got_reloc;
+ edir->has_non_got_reloc |= eind->has_non_got_reloc;
+
_bfd_elf_link_hash_copy_indirect (info, dir, ind);
}
unsigned int r_type;
unsigned long r_symndx;
struct elf_link_hash_entry *h;
+ struct _bfd_sparc_elf_link_hash_entry *eh;
Elf_Internal_Sym *isym;
r_symndx = SPARC_ELF_R_SYMNDX (htab, rel->r_info);
}
r_type = sparc_elf_tls_transition (info, abfd, r_type, h == NULL);
+ eh = (struct _bfd_sparc_elf_link_hash_entry *) h;
+
switch (r_type)
{
case R_SPARC_TLS_LDM_HI22:
case R_SPARC_TLS_LDM_LO10:
htab->tls_ldm_got.refcount += 1;
+ if (eh != NULL)
+ eh->has_got_reloc = 1;
break;
case R_SPARC_TLS_LE_HIX22:
if (!_bfd_elf_create_got_section (htab->elf.dynobj, info))
return FALSE;
}
+
+ if (eh != NULL)
+ eh->has_got_reloc = 1;
break;
case R_SPARC_TLS_GD_CALL:
goto r_sparc_plt32;
}
h->plt.refcount += 1;
+
+ eh = (struct _bfd_sparc_elf_link_hash_entry *) h;
+ eh->has_got_reloc = 1;
break;
case R_SPARC_PC10:
if (h != NULL)
h->non_got_ref = 1;
+ if (eh != NULL && (sec->flags & SEC_CODE) != 0)
+ eh->has_non_got_reloc = 1;
+
r_sparc_plt32:
if (h != NULL && !bfd_link_pic (info))
{
return TRUE;
}
+/* Remove undefined weak symbol from the dynamic symbol table if it
+ is resolved to 0. */
+
+bfd_boolean
+_bfd_sparc_elf_fixup_symbol (struct bfd_link_info *info,
+ struct elf_link_hash_entry *h)
+{
+ if (h->dynindx != -1
+ && UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
+ _bfd_sparc_elf_hash_entry (h)))
+ {
+ h->dynindx = -1;
+ _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
+ h->dynstr_index);
+ }
+ return TRUE;
+}
+
/* Adjust a symbol defined by a dynamic object and referenced by a
regular object. The current definition is in some section of the
dynamic object, but we're not including those sections. We have to
struct _bfd_sparc_elf_link_hash_table *htab;
struct _bfd_sparc_elf_link_hash_entry *eh;
struct _bfd_sparc_elf_dyn_relocs *p;
+ bfd_boolean resolved_to_zero;
if (h->root.type == bfd_link_hash_indirect)
return TRUE;
htab = _bfd_sparc_elf_hash_table (info);
BFD_ASSERT (htab != NULL);
+ eh = (struct _bfd_sparc_elf_link_hash_entry *) h;
+ resolved_to_zero = UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh);
+
if ((htab->elf.dynamic_sections_created
&& h->plt.refcount > 0)
|| (h->type == STT_GNU_IFUNC
/* Make sure this symbol is output as a dynamic symbol.
Undefined weak syms won't yet be marked as dynamic. */
if (h->dynindx == -1
- && !h->forced_local)
+ && !h->forced_local
+ && !resolved_to_zero)
{
if (! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
/* Make room for this entry. */
s->size += htab->plt_entry_size;
- /* We also need to make an entry in the .rela.plt section. */
- if (s == htab->elf.splt)
- htab->elf.srelplt->size += SPARC_ELF_RELA_BYTES (htab);
- else
- htab->elf.irelplt->size += SPARC_ELF_RELA_BYTES (htab);
+ /* There should be no PLT relocations against resolved undefined
+ weak symbols in the executable. */
+ if (!resolved_to_zero)
+ {
+ /* We also need to make an entry in the .rela.plt section. */
+ if (s == htab->elf.splt)
+ htab->elf.srelplt->size += SPARC_ELF_RELA_BYTES (htab);
+ else
+ htab->elf.irelplt->size += SPARC_ELF_RELA_BYTES (htab);
+ }
if (htab->is_vxworks)
{
/* Make sure this symbol is output as a dynamic symbol.
Undefined weak syms won't yet be marked as dynamic. */
if (h->dynindx == -1
- && !h->forced_local)
+ && !h->forced_local
+ && !resolved_to_zero)
{
if (! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
dyn = htab->elf.dynamic_sections_created;
/* R_SPARC_TLS_IE_{HI22,LO10} needs one dynamic relocation,
R_SPARC_TLS_GD_{HI22,LO10} needs one if local symbol and two if
- global. */
+ global. No dynamic relocations are needed against resolved
+ undefined weak symbols in an executable. */
if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
|| tls_type == GOT_TLS_IE
|| h->type == STT_GNU_IFUNC)
htab->elf.srelgot->size += SPARC_ELF_RELA_BYTES (htab);
else if (tls_type == GOT_TLS_GD)
htab->elf.srelgot->size += 2 * SPARC_ELF_RELA_BYTES (htab);
- else if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn,
- bfd_link_pic (info),
- h))
+ else if (((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ && !resolved_to_zero)
+ || h->root.type != bfd_link_hash_undefweak)
+ && WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn,
+ bfd_link_pic (info),
+ h))
htab->elf.srelgot->size += SPARC_ELF_RELA_BYTES (htab);
}
else
h->got.offset = (bfd_vma) -1;
- eh = (struct _bfd_sparc_elf_link_hash_entry *) h;
if (eh->dyn_relocs == NULL)
return TRUE;
}
/* Also discard relocs on undefined weak syms with non-default
- visibility. */
+ visibility or in PIE. */
if (eh->dyn_relocs != NULL
&& h->root.type == bfd_link_hash_undefweak)
{
- if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
- eh->dyn_relocs = NULL;
+ /* An undefined weak symbol is never
+ bound locally in a shared library. */
+
+ if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
+ || resolved_to_zero)
+ {
+ if (h->non_got_ref)
+ {
+ /* Keep dynamic non-GOT/non-PLT relocation so that we
+ can branch to 0 without PLT. */
+ struct _bfd_sparc_elf_dyn_relocs **pp;
+
+ for (pp = &eh->dyn_relocs; (p = *pp) != NULL;)
+ if (p->pc_count == 0)
+ *pp = p->next;
+ else
+ {
+ /* Remove other relocations. */
+ p->count = p->pc_count;
+ pp = &p->next;
+ }
+
+ if (eh->dyn_relocs != NULL)
+ {
+ /* Make sure undefined weak symbols are output
+ as dynamic symbols in PIEs for dynamic non-GOT
+ non-PLT reloations. */
+ if (! bfd_elf_link_record_dynamic_symbol (info, h))
+ return FALSE;
+ }
+ }
+ else
+ eh->dyn_relocs = NULL;
+ }
/* Make sure undefined weak symbols are output as a dynamic
symbol in PIEs. */
symbols which turn out to need copy relocs or are not
dynamic. */
- if (!h->non_got_ref
+ if ((!h->non_got_ref
+ || (h->root.type == bfd_link_hash_undefweak
+ && !resolved_to_zero))
&& ((h->def_dynamic
&& !h->def_regular)
|| (htab->elf.dynamic_sections_created
/* Make sure this symbol is output as a dynamic symbol.
Undefined weak syms won't yet be marked as dynamic. */
if (h->dynindx == -1
- && !h->forced_local)
+ && !h->forced_local
+ && !resolved_to_zero)
{
if (! bfd_elf_link_record_dynamic_symbol (info, h))
return FALSE;
{
/* Set the contents of the .interp section to the interpreter. */
if (bfd_link_executable (info) && !info->nointerp)
- {
- s = bfd_get_linker_section (dynobj, ".interp");
- BFD_ASSERT (s != NULL);
- s->size = htab->dynamic_interpreter_size;
- s->contents = (unsigned char *) htab->dynamic_interpreter;
- }
+ {
+ s = bfd_get_linker_section (dynobj, ".interp");
+ BFD_ASSERT (s != NULL);
+ s->size = htab->dynamic_interpreter_size;
+ s->contents = (unsigned char *) htab->dynamic_interpreter;
+ htab->interp = s;
+ }
}
/* Set up .got offsets for local syms, and space for local dynamic
reloc_howto_type *howto;
unsigned long r_symndx;
struct elf_link_hash_entry *h;
+ struct _bfd_sparc_elf_link_hash_entry *eh;
Elf_Internal_Sym *sym;
asection *sec;
bfd_vma relocation, off;
bfd_reloc_status_type r;
bfd_boolean is_plt = FALSE;
bfd_boolean unresolved_reloc;
+ bfd_boolean resolved_to_zero;
r_type = SPARC_ELF_R_TYPE (rel->r_info);
if (r_type == R_SPARC_GNU_VTINHERIT
}
}
+ eh = (struct _bfd_sparc_elf_link_hash_entry *) h;
+ resolved_to_zero = (eh != NULL
+ && UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh));
+
switch (r_type)
{
case R_SPARC_GOTDATA_OP_HIX22:
|| is_vxworks_tls)
break;
+ /* Copy dynamic function pointer relocations. Don't generate
+ dynamic relocations against resolved undefined weak symbols
+ in PIE. */
if ((bfd_link_pic (info)
&& (h == NULL
- || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
- || h->root.type != bfd_link_hash_undefweak)
+ || ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ && !resolved_to_zero)
+ || h->root.type != bfd_link_hash_undefweak))
&& (! howto->pc_relative
|| !SYMBOL_CALLS_LOCAL (info, h)))
|| (!bfd_link_pic (info)
&& !h->non_got_ref
&& ((h->def_dynamic
&& !h->def_regular)
- || h->root.type == bfd_link_hash_undefweak
+ || (h->root.type == bfd_link_hash_undefweak
+ && !resolved_to_zero)
|| h->root.type == bfd_link_hash_undefined)))
{
Elf_Internal_Rela outrel;
{
struct _bfd_sparc_elf_link_hash_table *htab;
const struct elf_backend_data *bed;
+ struct _bfd_sparc_elf_link_hash_entry *eh;
+ bfd_boolean local_undefweak;
htab = _bfd_sparc_elf_hash_table (info);
BFD_ASSERT (htab != NULL);
bed = get_elf_backend_data (output_bfd);
+ eh = (struct _bfd_sparc_elf_link_hash_entry *) h;
+
+ /* We keep PLT/GOT entries without dynamic PLT/GOT relocations for
+ resolved undefined weak symbols in executable so that their
+ references have value 0 at run-time. */
+ local_undefweak = UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh);
+
if (h->plt.offset != (bfd_vma) -1)
{
asection *splt;
loc += rela_index * bed->s->sizeof_rela;
bed->s->swap_reloca_out (output_bfd, &rela, loc);
- if (!h->def_regular)
+ if (!local_undefweak
+ && !h->def_regular)
{
/* Mark the symbol as undefined, rather than as defined in
the .plt section. Leave the value alone. */
}
}
+ /* Don't generate dynamic GOT relocation against undefined weak
+ symbol in executable. */
if (h->got.offset != (bfd_vma) -1
&& _bfd_sparc_elf_hash_entry(h)->tls_type != GOT_TLS_GD
- && _bfd_sparc_elf_hash_entry(h)->tls_type != GOT_TLS_IE)
+ && _bfd_sparc_elf_hash_entry(h)->tls_type != GOT_TLS_IE
+ && !local_undefweak)
{
asection *sgot;
asection *srela;
h, NULL);
}
+/* Finish up undefined weak symbol handling in PIE. Fill its PLT entry
+ here since undefined weak symbol may not be dynamic and may not be
+ called for _bfd_sparc_elf_finish_dynamic_symbol. */
+
+static bfd_boolean
+pie_finish_undefweak_symbol (struct bfd_hash_entry *bh,
+ void *inf)
+{
+ struct elf_link_hash_entry *h = (struct elf_link_hash_entry *) bh;
+ struct bfd_link_info *info = (struct bfd_link_info *) inf;
+
+ if (h->root.type != bfd_link_hash_undefweak
+ || h->dynindx != -1)
+ return TRUE;
+
+ return _bfd_sparc_elf_finish_dynamic_symbol (info->output_bfd, info,
+ h, NULL);
+}
+
bfd_boolean
_bfd_sparc_elf_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
{
/* Fill PLT and GOT entries for local STT_GNU_IFUNC symbols. */
htab_traverse (htab->loc_hash_table, finish_local_dynamic_symbol, info);
+ /* Fill PLT entries for undefined weak symbols in PIE. */
+ if (bfd_link_pie (info))
+ bfd_hash_traverse (&info->hash->table,
+ pie_finish_undefweak_symbol,
+ info);
return TRUE;
}
projects / external / binutils.git / commitdiff