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Diffstat (limited to 'bfd/elf64-x86-64.c')
-rw-r--r--bfd/elf64-x86-64.c86
1 files changed, 64 insertions, 22 deletions
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index f13b4d2207c..c0ce57d708d 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -324,6 +324,12 @@ elf64_x86_64_grok_psinfo (abfd, note)
#define ELF_DYNAMIC_INTERPRETER "/lib/ld64.so.1"
+/* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
+ copying dynamic variables from a shared lib into an app's dynbss
+ section, and instead use a dynamic relocation to point into the
+ shared lib. */
+#define ELIMINATE_COPY_RELOCS 1
+
/* The size in bytes of an entry in the global offset table. */
#define GOT_ENTRY_SIZE 8
@@ -616,7 +622,18 @@ elf64_x86_64_copy_indirect_symbol (bed, dir, ind)
eind->tls_type = GOT_UNKNOWN;
}
- _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
+ if (ELIMINATE_COPY_RELOCS
+ && ind->root.type != bfd_link_hash_indirect
+ && (dir->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
+ /* If called to transfer flags for a weakdef during processing
+ of elf_adjust_dynamic_symbol, don't copy ELF_LINK_NON_GOT_REF.
+ We clear it ourselves for ELIMINATE_COPY_RELOCS. */
+ dir->elf_link_hash_flags |=
+ (ind->elf_link_hash_flags & (ELF_LINK_HASH_REF_DYNAMIC
+ | ELF_LINK_HASH_REF_REGULAR
+ | ELF_LINK_HASH_REF_REGULAR_NONWEAK));
+ else
+ _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
}
static bfd_boolean
@@ -914,7 +931,8 @@ elf64_x86_64_check_relocs (abfd, info, sec, relocs)
|| h->root.type == bfd_link_hash_defweak
|| (h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_REGULAR) == 0))))
- || (!info->shared
+ || (ELIMINATE_COPY_RELOCS
+ && !info->shared
&& (sec->flags & SEC_ALLOC) != 0
&& h != NULL
&& (h->root.type == bfd_link_hash_defweak
@@ -1189,8 +1207,6 @@ elf64_x86_64_adjust_dynamic_symbol (info, h)
struct elf_link_hash_entry *h;
{
struct elf64_x86_64_link_hash_table *htab;
- struct elf64_x86_64_link_hash_entry * eh;
- struct elf64_x86_64_dyn_relocs *p;
asection *s;
unsigned int power_of_two;
@@ -1235,6 +1251,10 @@ elf64_x86_64_adjust_dynamic_symbol (info, h)
|| h->weakdef->root.type == bfd_link_hash_defweak);
h->root.u.def.section = h->weakdef->root.u.def.section;
h->root.u.def.value = h->weakdef->root.u.def.value;
+ if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
+ h->elf_link_hash_flags
+ = ((h->elf_link_hash_flags & ~ELF_LINK_NON_GOT_REF)
+ | (h->weakdef->elf_link_hash_flags & ELF_LINK_NON_GOT_REF));
return TRUE;
}
@@ -1260,20 +1280,26 @@ elf64_x86_64_adjust_dynamic_symbol (info, h)
return TRUE;
}
- eh = (struct elf64_x86_64_link_hash_entry *) h;
- for (p = eh->dyn_relocs; p != NULL; p = p->next)
+ if (ELIMINATE_COPY_RELOCS)
{
- s = p->sec->output_section;
- if (s != NULL && (s->flags & SEC_READONLY) != 0)
- break;
- }
+ struct elf64_x86_64_link_hash_entry * eh;
+ struct elf64_x86_64_dyn_relocs *p;
- /* If we didn't find any dynamic relocs in read-only sections, then
- we'll be keeping the dynamic relocs and avoiding the copy reloc. */
- if (p == NULL)
- {
- h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
- return TRUE;
+ eh = (struct elf64_x86_64_link_hash_entry *) h;
+ for (p = eh->dyn_relocs; p != NULL; p = p->next)
+ {
+ s = p->sec->output_section;
+ if (s != NULL && (s->flags & SEC_READONLY) != 0)
+ break;
+ }
+
+ /* If we didn't find any dynamic relocs in read-only sections, then
+ we'll be keeping the dynamic relocs and avoiding the copy reloc. */
+ if (p == NULL)
+ {
+ h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
+ return TRUE;
+ }
}
/* We must allocate the symbol in our .dynbss section, which will
@@ -1359,7 +1385,9 @@ allocate_dynrelocs (h, inf)
htab = elf64_x86_64_hash_table (info);
if (htab->elf.dynamic_sections_created
- && h->plt.refcount > 0)
+ && h->plt.refcount > 0
+ && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ || h->root.type != bfd_link_hash_undefweak))
{
/* Make sure this symbol is output as a dynamic symbol.
Undefined weak syms won't yet be marked as dynamic. */
@@ -1452,7 +1480,9 @@ allocate_dynrelocs (h, inf)
htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
else if (tls_type == GOT_TLS_GD)
htab->srelgot->_raw_size += 2 * sizeof (Elf64_External_Rela);
- else if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h))
+ else if ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ || h->root.type != bfd_link_hash_undefweak)
+ && WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h))
htab->srelgot->_raw_size += sizeof (Elf64_External_Rela);
}
else
@@ -1486,8 +1516,14 @@ allocate_dynrelocs (h, inf)
pp = &p->next;
}
}
+
+ /* Also discard relocs on undefined weak syms with non-default
+ visibility. */
+ if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
+ && h->root.type == bfd_link_hash_undefweak)
+ eh->dyn_relocs = NULL;
}
- else
+ else if (ELIMINATE_COPY_RELOCS)
{
/* For the non-shared case, discard space for relocs against
symbols which turn out to need copy relocs or are not
@@ -1950,7 +1986,9 @@ elf64_x86_64_relocate_section (output_bfd, info, input_bfd, input_section,
&& (info->symbolic
|| h->dynindx == -1
|| (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
- && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
+ && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
+ || (ELF_ST_VISIBILITY (h->other)
+ && h->root.type == bfd_link_hash_undefweak))
{
/* This is actually a static link, or it is a -Bsymbolic
link and the symbol is defined locally, or the symbol
@@ -2069,6 +2107,9 @@ elf64_x86_64_relocate_section (output_bfd, info, input_bfd, input_section,
break;
if ((info->shared
+ && (h == NULL
+ || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ || h->root.type != bfd_link_hash_undefweak)
&& ((r_type != R_X86_64_PC8
&& r_type != R_X86_64_PC16
&& r_type != R_X86_64_PC32)
@@ -2077,7 +2118,8 @@ elf64_x86_64_relocate_section (output_bfd, info, input_bfd, input_section,
&& (! info->symbolic
|| (h->elf_link_hash_flags
& ELF_LINK_HASH_DEF_REGULAR) == 0))))
- || (!info->shared
+ || (ELIMINATE_COPY_RELOCS
+ && !info->shared
&& h != NULL
&& h->dynindx != -1
&& (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
@@ -2351,7 +2393,7 @@ elf64_x86_64_relocate_section (output_bfd, info, input_bfd, input_section,
{
if (indx == 0)
{
- BFD_ASSERT (! unresolved_reloc);
+ BFD_ASSERT (! unresolved_reloc);
bfd_put_64 (output_bfd,
relocation - dtpoff_base (info),
htab->sgot->contents + off + GOT_ENTRY_SIZE);