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[binutils-gdb] PowerPC undefweak handling
- From: Alan Modra <amodra at sourceware dot org>
- To: bfd-cvs at sourceware dot org
- Date: 27 Apr 2017 02:25:18 -0000
- Subject: [binutils-gdb] PowerPC undefweak handling
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=21d68fcd0c2f9113369d860ee1e5841bfacc35ff
commit 21d68fcd0c2f9113369d860ee1e5841bfacc35ff
Author: Alan Modra <amodra@gmail.com>
Date: Thu Apr 27 09:19:26 2017 +0930
PowerPC undefweak handling
This patch fixes a number of cases where -z nodynamic-undefined-weak
was not effective in preventing dynamic relocations or linkage stubs.
* elf32-ppc.c (UNDEFWEAK_NO_DYNAMIC_RELOC): Define.
(ppc_elf_select_plt_layout, ppc_elf_tls_setup): Use it.
(ppc_elf_adjust_dynamic_symbol, allocate_dynrelocs): Likewise.
(ppc_elf_relocate_section): Likewise. Delete silly optimisation
for undef and undefweak dyn_relocs.
* elf64-ppc.c (UNDEFWEAK_NO_DYNAMIC_RELOC): Define.
(ppc64_elf_adjust_dynamic_symbol, ppc64_elf_tls_setup): Use it.
(allocate_got, allocate_dynrelocs): Likewise.
(ppc64_elf_relocate_section): Likewise.
Diff:
---
bfd/ChangeLog | 12 ++++++++++++
bfd/elf32-ppc.c | 38 ++++++++++++++++----------------------
bfd/elf64-ppc.c | 27 +++++++++++++--------------
3 files changed, 41 insertions(+), 36 deletions(-)
diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 3234230..6cda710 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,15 @@
+2017-04-27 Alan Modra <amodra@gmail.com>
+
+ * elf32-ppc.c (UNDEFWEAK_NO_DYNAMIC_RELOC): Define.
+ (ppc_elf_select_plt_layout, ppc_elf_tls_setup): Use it.
+ (ppc_elf_adjust_dynamic_symbol, allocate_dynrelocs): Likewise.
+ (ppc_elf_relocate_section): Likewise. Delete silly optimisation
+ for undef and undefweak dyn_relocs.
+ * elf64-ppc.c (UNDEFWEAK_NO_DYNAMIC_RELOC): Define.
+ (ppc64_elf_adjust_dynamic_symbol, ppc64_elf_tls_setup): Use it.
+ (allocate_got, allocate_dynrelocs): Likewise.
+ (ppc64_elf_relocate_section): Likewise.
+
2017-04-26 H.J. Lu <hongjiu.lu@intel.com>
* elf32-i386.c (elf_i386_size_dynamic_sections): Alwasys add
diff --git a/bfd/elf32-ppc.c b/bfd/elf32-ppc.c
index 6a24a46..7a46233 100644
--- a/bfd/elf32-ppc.c
+++ b/bfd/elf32-ppc.c
@@ -3221,6 +3221,13 @@ must_be_dyn_reloc (struct bfd_link_info *info,
}
}
+/* Whether an undefined weak symbol should resolve to its link-time
+ value, even in PIC or PIE objects. */
+#define UNDEFWEAK_NO_DYNAMIC_RELOC(INFO, H) \
+ ((H)->root.type == bfd_link_hash_undefweak \
+ && (ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT \
+ || (INFO)->dynamic_undefined_weak == 0))
+
/* 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
@@ -4996,8 +5003,7 @@ ppc_elf_select_plt_layout (bfd *output_bfd ATTRIBUTE_UNUSED,
|| h->needs_plt)
&& h->ref_regular
&& !(SYMBOL_CALLS_LOCAL (info, h)
- || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
- && h->root.type == bfd_link_hash_undefweak)))
+ || UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)))
{
/* Profiling of shared libs (and pies) is not supported with
secure plt, because ppc32 does profiling before a
@@ -5297,8 +5303,7 @@ ppc_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
&& (tga->type == STT_FUNC
|| tga->needs_plt)
&& !(SYMBOL_CALLS_LOCAL (info, tga)
- || (ELF_ST_VISIBILITY (tga->other) != STV_DEFAULT
- && tga->root.type == bfd_link_hash_undefweak)))
+ || UNDEFWEAK_NO_DYNAMIC_RELOC (info, tga)))
{
struct plt_entry *ent;
for (ent = tga->plt.plist; ent != NULL; ent = ent->next)
@@ -5684,8 +5689,7 @@ ppc_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
if (ent == NULL
|| (h->type != STT_GNU_IFUNC
&& (SYMBOL_CALLS_LOCAL (info, h)
- || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
- && h->root.type == bfd_link_hash_undefweak))))
+ || UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))))
{
/* A PLT entry is not required/allowed when:
@@ -6018,8 +6022,7 @@ allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
|| (htab->elf.dynamic_sections_created
&& eh->elf.dynindx != -1
&& !SYMBOL_REFERENCES_LOCAL (info, &eh->elf)))
- && (ELF_ST_VISIBILITY (eh->elf.other) == STV_DEFAULT
- || eh->elf.root.type != bfd_link_hash_undefweak))
+ && !UNDEFWEAK_NO_DYNAMIC_RELOC (info, &eh->elf))
{
asection *rsec = htab->elf.srelgot;
@@ -6060,9 +6063,7 @@ allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
/* Also discard relocs on undefined weak syms with non-default
visibility, or when dynamic_undefined_weak says so. */
- else if (h->root.type == bfd_link_hash_undefweak
- && (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
- || info->dynamic_undefined_weak == 0))
+ else if (UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))
eh->dyn_relocs = NULL;
/* Relocs that use pc_count are those that appear on a call insn,
@@ -8504,8 +8505,7 @@ ppc_elf_relocate_section (bfd *output_bfd,
if (!htab->elf.dynamic_sections_created
|| h->dynindx == -1
|| SYMBOL_REFERENCES_LOCAL (info, h)
- || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
- && h->root.type == bfd_link_hash_undefweak))
+ || UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))
/* This is actually a static link, or it is a
-Bsymbolic link and the symbol is defined
locally, or the symbol was forced to be local
@@ -8574,8 +8574,7 @@ ppc_elf_relocate_section (bfd *output_bfd,
if (indx != 0
|| (bfd_link_pic (info)
&& (h == NULL
- || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
- || h->root.type != bfd_link_hash_undefweak
+ || !UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)
|| offp == &htab->tlsld_got.offset)))
{
asection *rsec = htab->elf.srelgot;
@@ -8862,9 +8861,7 @@ ppc_elf_relocate_section (bfd *output_bfd,
&& !(h != NULL
&& ((h->root.type == bfd_link_hash_undefined
&& ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
- || (h->root.type == bfd_link_hash_undefweak
- && (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
- || info->dynamic_undefined_weak == 0))))
+ || UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)))
&& (must_be_dyn_reloc (info, r_type)
|| !SYMBOL_CALLS_LOCAL (info, h)))
|| (ELIMINATE_COPY_RELOCS
@@ -8905,10 +8902,7 @@ ppc_elf_relocate_section (bfd *output_bfd,
if (skip)
memset (&outrel, 0, sizeof outrel);
- else if ((h != NULL
- && (h->root.type == bfd_link_hash_undefined
- || h->root.type == bfd_link_hash_undefweak))
- || !SYMBOL_REFERENCES_LOCAL (info, h))
+ else if (!SYMBOL_REFERENCES_LOCAL (info, h))
{
indx = h->dynindx;
BFD_ASSERT (indx != -1);
diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index 2e8f338..a20d9b3 100644
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -3820,6 +3820,13 @@ must_be_dyn_reloc (struct bfd_link_info *info,
}
}
+/* Whether an undefined weak symbol should resolve to its link-time
+ value, even in PIC or PIE objects. */
+#define UNDEFWEAK_NO_DYNAMIC_RELOC(INFO, H) \
+ ((H)->root.type == bfd_link_hash_undefweak \
+ && (ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT \
+ || (INFO)->dynamic_undefined_weak == 0))
+
/* 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
@@ -7297,8 +7304,7 @@ ppc64_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
if (ent == NULL
|| (h->type != STT_GNU_IFUNC
&& (SYMBOL_CALLS_LOCAL (info, h)
- || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
- && h->root.type == bfd_link_hash_undefweak)))
+ || UNDEFWEAK_NO_DYNAMIC_RELOC (info, h)))
|| ((struct ppc_link_hash_entry *) h)->save_res)
{
h->plt.plist = NULL;
@@ -8354,8 +8360,7 @@ ppc64_elf_tls_setup (struct bfd_link_info *info)
&& (tga_fd->type == STT_FUNC
|| tga_fd->needs_plt)
&& !(SYMBOL_CALLS_LOCAL (info, tga_fd)
- || (ELF_ST_VISIBILITY (tga_fd->other) != STV_DEFAULT
- && tga_fd->root.type == bfd_link_hash_undefweak)))
+ || UNDEFWEAK_NO_DYNAMIC_RELOC (info, tga_fd)))
{
struct plt_entry *ent;
@@ -9659,8 +9664,7 @@ allocate_got (struct elf_link_hash_entry *h,
|| (htab->elf.dynamic_sections_created
&& h->dynindx != -1
&& !SYMBOL_REFERENCES_LOCAL (info, h)))
- && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
- || h->root.type != bfd_link_hash_undefweak))
+ && !UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))
{
asection *relgot = ppc64_elf_tdata (gent->owner)->relgot;
relgot->size += rentsize;
@@ -9795,9 +9799,7 @@ allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
/* Also discard relocs on undefined weak syms with non-default
visibility, or when dynamic_undefined_weak says so. */
- else if (h->root.type == bfd_link_hash_undefweak
- && (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
- || info->dynamic_undefined_weak == 0))
+ else if (UNDEFWEAK_NO_DYNAMIC_RELOC (info, h))
eh->dyn_relocs = NULL;
if (eh->dyn_relocs != NULL)
@@ -14458,8 +14460,7 @@ ppc64_elf_relocate_section (bfd *output_bfd,
if (!htab->elf.dynamic_sections_created
|| h->elf.dynindx == -1
|| SYMBOL_REFERENCES_LOCAL (info, &h->elf)
- || (ELF_ST_VISIBILITY (h->elf.other) != STV_DEFAULT
- && h->elf.root.type == bfd_link_hash_undefweak))
+ || UNDEFWEAK_NO_DYNAMIC_RELOC (info, &h->elf))
/* This is actually a static link, or it is a
-Bsymbolic link and the symbol is defined
locally, or the symbol was forced to be local
@@ -14525,9 +14526,7 @@ ppc64_elf_relocate_section (bfd *output_bfd,
else if (indx != 0
|| (bfd_link_pic (info)
&& (h == NULL
- || (ELF_ST_VISIBILITY (h->elf.other)
- == STV_DEFAULT)
- || h->elf.root.type != bfd_link_hash_undefweak
+ || !UNDEFWEAK_NO_DYNAMIC_RELOC (info, &h->elf)
|| (tls_type == (TLS_TLS | TLS_LD)
&& !h->elf.def_dynamic))))
relgot = ppc64_elf_tdata (ent->owner)->relgot;