ppc32 linker bug
Andreas Jaeger
aj@suse.de
Fri May 2 06:55:00 GMT 2003
Alan Modra <amodra@bigpond.net.au> writes:
> On Thu, May 01, 2003 at 04:45:48PM +0200, Andreas Jaeger wrote:
>> Is this something that should be done for all archs? Can I enable it
>> for x86-64? Is there a testcase I should look at?
>
> I considered doing it for all archs, but decided against it this
> close to a release. A testcase is something like the following
> assembly linked against libc.
>
> .rodata
.section .rodata
> .quad timezone
> .data
> .quad environ
With my old binutils I get:
$ gcc t.o -o t
/usr/lib64/gcc-lib/x86_64-suse-linux/3.3/../../../../lib64/crt1.o(.text+0x21): In function `_start':
: undefined reference to `main'
/usr/lib64/gcc-lib/x86_64-suse-linux/3.3/../../../../x86_64-suse-linux/bin/ld: t.o(.data+0x0): unresolvable relocation against symbol `environ@@GLIBC_2.2.5'
collect2: ld returned 1 exit status
With my patched binutils:
/usr/lib64/gcc-lib/x86_64-suse-linux/3.3/../../../../lib64/crt1.o(.text+0x21): In function `_start':
: undefined reference to `main'
So, this looks fine to me.
Here's a patch. I'll commit it later today to both branch and
mainline. Could you give it a quick review?
The testsuite passed fine with this change.
Thanks,
Andreas
2003-05-02 Andreas Jaeger <aj@suse.de>
* elf64-x86-64.c (elf_x86_64_copy_indirect_symbol): Don't copy
ELF_LINK_NON_GOT_REF for weakdefs when symbol already adjusted.
(ELIMINATE_COPY_RELOCS): Define as one. Use throughout.
(elf_x86_64_adjust_dynamic_symbol): For weak symbols, copy
ELF_LINK_NON_GOT_REF from weakdef.
============================================================
Index: bfd/elf64-x86-64.c
--- bfd/elf64-x86-64.c 19 Feb 2003 14:14:16 -0000 1.56
+++ bfd/elf64-x86-64.c 2 May 2003 06:29:45 -0000
@@ -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,
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, s
|| 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
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->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
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
@@ -1487,7 +1513,7 @@ allocate_dynrelocs (h, inf)
}
}
}
- 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
@@ -2077,7 +2103,8 @@ elf64_x86_64_relocate_section (output_bf
&& (! 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 +2378,7 @@ elf64_x86_64_relocate_section (output_bf
{
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);
--
Andreas Jaeger
SuSE Labs aj@suse.de
private aj@arthur.inka.de
http://www.suse.de/~aj
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