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Date
SubjectRFC: Add -mshared option to x86 ELF assembler
From
On Fri, May 8, 2015 at 1:16 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Fri, May 8, 2015 at 5:09 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
>> On Thu, May 7, 2015 at 8:22 PM, Andy Lutomirski <luto@amacapital.net> wrote:
>>> On Thu, May 7, 2015 at 9:21 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
>>>> On Thu, May 7, 2015 at 4:52 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>>>>>> On 07.05.15 at 08:02, <luto@amacapital.net> wrote:
>>>>>> AFAICT gas will produce relocations for jumps to global labels in the
>>>>>> same file. This doesn't seem directly harmful to me, except that, on
>>>>>> x86, it forces five-byte jumps instead of two-byte jumps.
>>>>>>
>>>>>> This seems especially unfortunate, since even hidden and protected
>>>>>> symbols have this problem.
>>>>>>
>>>>>> Given that many users don't want interposition support (especially the
>>>>>> kernel and anyone using .hidden or .protected), it would be nice to
>>>>>> have a command-line option to turn this off and probably also to turn
>>>>>> it off by default for hidden and protected symbols. Can gas do this?
>>>>>
>>>>> I've been running with the below changes (taken off of a bigger set
>>>>> of changes, so the line numbers may look a little odd) for the last
>>>>> couple of years. I never tried to submit this change because so far
>>>>> I couldn't find the time to check whether this would have any
>>>>> unwanted side effects on cases I don't normally use.
>>>>>
>>>>
>>>> This is the patch I checked in.
>>>>
>>>> Thanks.
>>>>
>>>> --
>>>> H.J.
>>>> ---
>>>> Branches to global non-weak symbols defined in the same segment with
>>>> non-default visibility can be optimized the same way as branches to
>>>> local symbols.
>>>
>>> Would it make sense to also add a command line option along the lines
>>> of gcc's -fno-semantic-interposition or some way to override the
>>> default visibility? AFAICS this patch helps but only if asm code gets
>>> liberally sprinkled with .hidden or .protected directives.
>>>
>>
>> This is what I checked in. With
>>
>> diff --git a/arch/x86/Makefile b/arch/x86/Makefile
>> index 2fda005..186e6f7 100644
>> --- a/arch/x86/Makefile
>> +++ b/arch/x86/Makefile
>> @@ -107,6 +107,10 @@ else
>> KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args)
>> endif
>>
>> +NO_SHARED_CFLAGS = $(call as-option,-Wa$(comma)-mno-shared)
>> +KBUILD_CFLAGS += $(NO_SHARED_CFLAGS)
>> +KBUILD_AFLAGS += $(NO_SHARED_CFLAGS)
>> +
>> # Make sure compiler does not have buggy stack-protector support.
>> ifdef CONFIG_CC_STACKPROTECTOR
>> cc_has_sp := $(srctree)/scripts/gcc-x86_$(BITS)-has-stack-protector.sh
>>
>> On kernel master branch, I got
>>
>> text data bss dec hex filename
>> 10934167 2275232 1609728 14819127 e21f37 vmlinux.old
>> 10934119 2275232 1609728 14819079 e21f07 vmlinux
>>
>> It saves 48 bytes.
>
> This is before I fixed:
>
> /* This is global to keep gas from relaxing the jumps */
> ENTRY(early_idt_handler)
> cld
>
> in arch/x86/kernel/head_64.S. With -mno-shared, we must
> make early_idt_handler weak to keep gas from relaxing the jumps.
>

Here is a patch to change the assembler default to optimize out
relocations to defined non-weak global branch targets with default
visibility. It will generate slightly smaller object files. But Linux
kernel will be broken unless early_idt_handler is marked weak.
I am little uncomfortable with -mshare and I don't like -mno-shared
very much either. I may just simply remove -mno-shared.


--
H.J.
---
This patch removes the newly added -mno-shared option from x86 ELF
assembler and adds -mshared option to x86 ELF assembler. By default,
assembler will optimize out relocations to defined non-weak global
branch targets with default visibility. The -mshared option tells
the assembler to generate code which may go into a shared library
where all non-weak global branch targets with default visibility can
be preempted. The resulting code is slightly bigger. This option
only affects the handling of branch instructions.

gas/

* config/tc-i386.c (no_shared): Renamed to ...
(shared): This.
(elf_symbol_resolved_in_segment_p): Add relocation argument.
Check PLT relocations and shared.
(md_estimate_size_before_relax): Pass fragP->fr_var to
elf_symbol_resolved_in_segment_p.
(OPTION_MNO_SHARED): Renamed to ...
(OPTION_MSHARED): This.
(md_longopts): Renamed -mno-shared to -mshared.
(md_show_usage): Likewise.
* doc/c-i386.texi: Likewise.

gas/testsuite/

* gas/i386/pcrel.d: Pass -mshared to assembler.
* gas/i386/relax-3.d: Likewise. Updated.
* gas/i386/x86-64-relax-2.d: Likewise.
* gas/i386/relax-3.s: Add test for PLT relocation.
* gas/i386/relax-4.d: Remove -mno-shared. Updated.
* gas/i386/x86-64-relax-3.d: Likewise.
From 180c819ed8be897f02ef15a201ce4ea47899749f Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Tue, 12 May 2015 16:52:11 -0700
Subject: [PATCH] Add -mshared option to x86 ELF assembler

This patch removes the newly added -mno-shared option from x86 ELF
assembler and adds -mshared option to x86 ELF assembler. By default,
assembler will optimize out relocations to defined non-weak global
branch targets with default visibility. The -mshared option tells
the assembler to generate code which may go into a shared library
where all non-weak global branch targets with default visibility can
be preempted. The resulting code is slightly bigger. This option
only affects the handling of branch instructions.

gas/

* config/tc-i386.c (no_shared): Renamed to ...
(shared): This.
(elf_symbol_resolved_in_segment_p): Add relocation argument.
Check PLT relocations and shared.
(md_estimate_size_before_relax): Pass fragP->fr_var to
elf_symbol_resolved_in_segment_p.
(OPTION_MNO_SHARED): Renamed to ...
(OPTION_MSHARED): This.
(md_longopts): Renamed -mno-shared to -mshared.
(md_show_usage): Likewise.
* doc/c-i386.texi: Likewise.

gas/testsuite/

* gas/i386/pcrel.d: Pass -mshared to assembler.
* gas/i386/relax-3.d: Likewise. Updated.
* gas/i386/x86-64-relax-2.d: Likewise.
* gas/i386/relax-3.s: Add test for PLT relocation.
* gas/i386/relax-4.d: Remove -mno-shared. Updated.
* gas/i386/x86-64-relax-3.d: Likewise.
---
gas/config/tc-i386.c | 36 ++++++++++++++++++++++-----------
gas/doc/c-i386.texi | 17 ++++++++--------
gas/testsuite/gas/i386/pcrel.d | 1 +
gas/testsuite/gas/i386/relax-3.d | 28 +++++++++++++------------
gas/testsuite/gas/i386/relax-3.s | 1 +
gas/testsuite/gas/i386/relax-4.d | 28 ++++++++++++-------------
gas/testsuite/gas/i386/x86-64-relax-2.d | 24 ++++++++++++----------
gas/testsuite/gas/i386/x86-64-relax-3.d | 28 ++++++++++++-------------
8 files changed, 91 insertions(+), 72 deletions(-)

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index db263ee..254548f 100644
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -525,8 +525,8 @@ static int use_big_obj = 0;
#endif

#if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
-/* 1 if not generating code for a shared library. */
-static int no_shared = 0;
+/* 1 if generating code for a shared library. */
+static int shared = 0;
#endif

/* 1 for intel syntax,
@@ -8823,7 +8823,7 @@ i386_frag_max_var (fragS *frag)

#if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
static int
-elf_symbol_resolved_in_segment_p (symbolS *fr_symbol)
+elf_symbol_resolved_in_segment_p (symbolS *fr_symbol, offsetT fr_var)
{
/* STT_GNU_IFUNC symbol must go through PLT. */
if ((symbol_get_bfdsym (fr_symbol)->flags
@@ -8834,13 +8834,24 @@ elf_symbol_resolved_in_segment_p (symbolS *fr_symbol)
/* Symbol may be weak or local. */
return !S_IS_WEAK (fr_symbol);

- /* Non-weak symbols won't be preempted. */
- if (no_shared)
+ /* Global symbols with non-default visibility can't be preempted. */
+ if (ELF_ST_VISIBILITY (S_GET_OTHER (fr_symbol)) != STV_DEFAULT)
return 1;

+ if (fr_var != NO_RELOC)
+ switch ((enum bfd_reloc_code_real) fr_var)
+ {
+ case BFD_RELOC_386_PLT32:
+ case BFD_RELOC_X86_64_PLT32:
+ /* Symbol with PLT relocatin may be preempted. */
+ return 0;
+ default:
+ abort ();
+ }
+
/* Global symbols with default visibility in a shared library may be
preempted by another definition. */
- return ELF_ST_VISIBILITY (S_GET_OTHER (fr_symbol)) != STV_DEFAULT;
+ return !shared;
}
#endif

@@ -8867,7 +8878,8 @@ md_estimate_size_before_relax (fragS *fragP, segT segment)
if (S_GET_SEGMENT (fragP->fr_symbol) != segment
#if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
|| (IS_ELF
- && !elf_symbol_resolved_in_segment_p (fragP->fr_symbol))
+ && !elf_symbol_resolved_in_segment_p (fragP->fr_symbol,
+ fragP->fr_var))
#endif
#if defined (OBJ_COFF) && defined (TE_PE)
|| (OUTPUT_FLAVOR == bfd_target_coff_flavour
@@ -9537,7 +9549,7 @@ const char *md_shortopts = "qn";
#define OPTION_MBIG_OBJ (OPTION_MD_BASE + 18)
#define OPTION_OMIT_LOCK_PREFIX (OPTION_MD_BASE + 19)
#define OPTION_MEVEXRCIG (OPTION_MD_BASE + 20)
-#define OPTION_MNO_SHARED (OPTION_MD_BASE + 21)
+#define OPTION_MSHARED (OPTION_MD_BASE + 21)

struct option md_longopts[] =
{
@@ -9548,7 +9560,7 @@ struct option md_longopts[] =
#endif
#if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
{"x32", no_argument, NULL, OPTION_X32},
- {"mno-shared", no_argument, NULL, OPTION_MNO_SHARED},
+ {"mshared", no_argument, NULL, OPTION_MSHARED},
#endif
{"divide", no_argument, NULL, OPTION_DIVIDE},
{"march", required_argument, NULL, OPTION_MARCH},
@@ -9610,8 +9622,8 @@ md_parse_option (int c, char *arg)
.stab instead of .stab.excl. We always use .stab anyhow. */
break;

- case OPTION_MNO_SHARED:
- no_shared = 1;
+ case OPTION_MSHARED:
+ shared = 1;
break;
#endif
#if (defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF) \
@@ -10043,7 +10055,7 @@ md_show_usage (FILE *stream)
fprintf (stream, _("\
-madd-bnd-prefix add BND prefix for all valid branches\n"));
fprintf (stream, _("\
- -mno-shared enable branch optimization for non shared code\n"));
+ -mshared disable branch optimization for shared code\n"));
# if defined (TE_PE) || defined (TE_PEP)
fprintf (stream, _("\
-mbig-obj generate big object files\n"));
diff --git a/gas/doc/c-i386.texi b/gas/doc/c-i386.texi
index 47bcbbb..a1997f5 100644
--- a/gas/doc/c-i386.texi
+++ b/gas/doc/c-i386.texi
@@ -298,15 +298,16 @@ The @code{.att_syntax} and @code{.intel_syntax} directives will take precedent.
This option forces the assembler to add BND prefix to all branches, even
if such prefix was not explicitly specified in the source code.

-@cindex @samp{-mno-shared} option, i386
-@cindex @samp{-mno-shared} option, x86-64
+@cindex @samp{-mshared} option, i386
+@cindex @samp{-mshared} option, x86-64
@item -mno-shared
-On ELF target, the assembler normally generates code which can go into a
-shared library where non-weak symbols can be preempted. The
-@samp{-mno-shared} option tells the assembler to generate code not for
-a shared library, where non-weak symbols won't be preempted. The
-resulting code is slightly smaller. This option mainly affects the
-handling of branch instructions.
+On ELF target, the assembler normally optimizes out relocations to
+defined non-weak global branch targets with default visibility. The
+@samp{-mshared} option tells the assembler to generate code which
+may go into a shared library where all non-weak global branch targets
+with default visibility can be preempted. The resulting code is
+slightly bigger. This option only affects the handling of branch
+instructions.

@cindex @samp{-mbig-obj} option, x86-64
@item -mbig-obj
diff --git a/gas/testsuite/gas/i386/pcrel.d b/gas/testsuite/gas/i386/pcrel.d
index 5b61c23..8a91a1a 100644
--- a/gas/testsuite/gas/i386/pcrel.d
+++ b/gas/testsuite/gas/i386/pcrel.d
@@ -1,4 +1,5 @@
#objdump: -drw
+#as: -mshared
#name: i386 pcrel reloc

.*: +file format .*i386.*
diff --git a/gas/testsuite/gas/i386/relax-3.d b/gas/testsuite/gas/i386/relax-3.d
index 8aa94e9..4610553 100644
--- a/gas/testsuite/gas/i386/relax-3.d
+++ b/gas/testsuite/gas/i386/relax-3.d
@@ -1,3 +1,4 @@
+#as: -mshared
#objdump: -dwr

.*: +file format .*
@@ -5,26 +6,27 @@
Disassembly of section .text:

0+ <foo>:
-[ ]*[a-f0-9]+: eb 1f jmp 21 <local>
-[ ]*[a-f0-9]+: eb 19 jmp 1d <hidden_def>
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 5 <foo\+0x5> 5: (R_386_PC)?(DISP)?32 global_def
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp a <foo\+0xa> a: (R_386_PC)?(DISP)?32 weak_def
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp f <foo\+0xf> f: (R_386_PC)?(DISP)?32 weak_hidden_undef
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 14 <foo\+0x14> 14: (R_386_PC)?(DISP)?32 weak_hidden_def
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 19 <foo\+0x19> 19: (R_386_PC)?(DISP)?32 hidden_undef
-
-0+1d <hidden_def>:
+[ ]*[a-f0-9]+: eb 24 jmp 26 <local>
+[ ]*[a-f0-9]+: eb 1e jmp 22 <hidden_def>
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 5 <foo\+0x5> 5: R_386_PC32 global_def
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp a <foo\+0xa> a: R_386_PLT32 global_def
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp f <foo\+0xf> f: R_386_PC32 weak_def
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 14 <foo\+0x14> 14: R_386_PC32 weak_hidden_undef
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 19 <foo\+0x19> 19: R_386_PC32 weak_hidden_def
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 1e <foo\+0x1e> 1e: R_386_PC32 hidden_undef
+
+0+22 <hidden_def>:
[ ]*[a-f0-9]+: c3 ret

-0+1e <weak_hidden_def>:
+0+23 <weak_hidden_def>:
[ ]*[a-f0-9]+: c3 ret

-0+1f <global_def>:
+0+24 <global_def>:
[ ]*[a-f0-9]+: c3 ret

-0+20 <weak_def>:
+0+25 <weak_def>:
[ ]*[a-f0-9]+: c3 ret

-0+21 <local>:
+0+26 <local>:
[ ]*[a-f0-9]+: c3 ret
#pass
diff --git a/gas/testsuite/gas/i386/relax-3.s b/gas/testsuite/gas/i386/relax-3.s
index ab52185..48ea917 100644
--- a/gas/testsuite/gas/i386/relax-3.s
+++ b/gas/testsuite/gas/i386/relax-3.s
@@ -4,6 +4,7 @@ foo:
jmp local
jmp hidden_def
jmp global_def
+ jmp global_def@PLT
jmp weak_def
jmp weak_hidden_undef
jmp weak_hidden_def
diff --git a/gas/testsuite/gas/i386/relax-4.d b/gas/testsuite/gas/i386/relax-4.d
index b188841..2039251 100644
--- a/gas/testsuite/gas/i386/relax-4.d
+++ b/gas/testsuite/gas/i386/relax-4.d
@@ -1,5 +1,4 @@
#source: relax-3.s
-#as: -mno-shared
#objdump: -dwr

.*: +file format .*
@@ -7,26 +6,27 @@
Disassembly of section .text:

0+ <foo>:
-[ ]*[a-f0-9]+: eb 1c jmp 1e <local>
-[ ]*[a-f0-9]+: eb 16 jmp 1a <hidden_def>
-[ ]*[a-f0-9]+: eb 16 jmp 1c <global_def>
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 7 <foo\+0x7> 7: (R_386_PC)?(DISP)?32 weak_def
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp c <foo\+0xc> c: (R_386_PC)?(DISP)?32 weak_hidden_undef
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 11 <foo\+0x11> 11: (R_386_PC)?(DISP)?32 weak_hidden_def
-[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 16 <foo\+0x16> 16: (R_386_PC)?(DISP)?32 hidden_undef
-
-0+1a <hidden_def>:
+[ ]*[a-f0-9]+: eb 21 jmp 23 <local>
+[ ]*[a-f0-9]+: eb 1b jmp 1f <hidden_def>
+[ ]*[a-f0-9]+: eb 1b jmp 21 <global_def>
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 7 <foo\+0x7> 7: R_386_PLT32 global_def
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp c <foo\+0xc> c: R_386_PC32 weak_def
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 11 <foo\+0x11> 11: R_386_PC32 weak_hidden_undef
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 16 <foo\+0x16> 16: R_386_PC32 weak_hidden_def
+[ ]*[a-f0-9]+: e9 fc ff ff ff jmp 1b <foo\+0x1b> 1b: R_386_PC32 hidden_undef
+
+0+1f <hidden_def>:
[ ]*[a-f0-9]+: c3 ret

-0+1b <weak_hidden_def>:
+0+20 <weak_hidden_def>:
[ ]*[a-f0-9]+: c3 ret

-0+1c <global_def>:
+0+21 <global_def>:
[ ]*[a-f0-9]+: c3 ret

-0+1d <weak_def>:
+0+22 <weak_def>:
[ ]*[a-f0-9]+: c3 ret

-0+1e <local>:
+0+23 <local>:
[ ]*[a-f0-9]+: c3 ret
#pass
diff --git a/gas/testsuite/gas/i386/x86-64-relax-2.d b/gas/testsuite/gas/i386/x86-64-relax-2.d
index 7b0bd56..c124102 100644
--- a/gas/testsuite/gas/i386/x86-64-relax-2.d
+++ b/gas/testsuite/gas/i386/x86-64-relax-2.d
@@ -1,4 +1,5 @@
#source: relax-3.s
+#as: -mshared
#objdump: -dwr

.*: +file format .*
@@ -7,26 +8,27 @@
Disassembly of section .text:

0+ <foo>:
-[ ]*[a-f0-9]+: eb 1f jmp 21 <local>
-[ ]*[a-f0-9]+: eb 19 jmp 1d <hidden_def>
+[ ]*[a-f0-9]+: eb 24 jmp 26 <local>
+[ ]*[a-f0-9]+: eb 1e jmp 22 <hidden_def>
[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 9 <foo\+0x9> 5: R_X86_64_PC32 global_def-0x4
-[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq e <foo\+0xe> a: R_X86_64_PC32 weak_def-0x4
-[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 13 <foo\+0x13> f: R_X86_64_PC32 weak_hidden_undef-0x4
-[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 18 <foo\+0x18> 14: R_X86_64_PC32 weak_hidden_def-0x4
-[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 1d <hidden_def> 19: R_X86_64_PC32 hidden_undef-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq e <foo\+0xe> a: R_X86_64_PLT32 global_def-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 13 <foo\+0x13> f: R_X86_64_PC32 weak_def-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 18 <foo\+0x18> 14: R_X86_64_PC32 weak_hidden_undef-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 1d <foo\+0x1d> 19: R_X86_64_PC32 weak_hidden_def-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 22 <hidden_def> 1e: R_X86_64_PC32 hidden_undef-0x4

-0+1d <hidden_def>:
+0+22 <hidden_def>:
[ ]*[a-f0-9]+: c3 retq

-0+1e <weak_hidden_def>:
+0+23 <weak_hidden_def>:
[ ]*[a-f0-9]+: c3 retq

-0+1f <global_def>:
+0+24 <global_def>:
[ ]*[a-f0-9]+: c3 retq

-0+20 <weak_def>:
+0+25 <weak_def>:
[ ]*[a-f0-9]+: c3 retq

-0+21 <local>:
+0+26 <local>:
[ ]*[a-f0-9]+: c3 retq
#pass
diff --git a/gas/testsuite/gas/i386/x86-64-relax-3.d b/gas/testsuite/gas/i386/x86-64-relax-3.d
index d0c7ee4..98fd28d 100644
--- a/gas/testsuite/gas/i386/x86-64-relax-3.d
+++ b/gas/testsuite/gas/i386/x86-64-relax-3.d
@@ -1,5 +1,4 @@
#source: relax-3.s
-#as: -mno-shared
#objdump: -dwr

.*: +file format .*
@@ -8,26 +7,27 @@
Disassembly of section .text:

0+ <foo>:
-[ ]*[a-f0-9]+: eb 1c jmp 1e <local>
-[ ]*[a-f0-9]+: eb 16 jmp 1a <hidden_def>
-[ ]*[a-f0-9]+: eb 16 jmp 1c <global_def>
-[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq b <foo\+0xb> 7: R_X86_64_PC32 weak_def-0x4
-[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 10 <foo\+0x10> c: R_X86_64_PC32 weak_hidden_undef-0x4
-[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 15 <foo\+0x15> 11: R_X86_64_PC32 weak_hidden_def-0x4
-[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 1a <hidden_def> 16: R_X86_64_PC32 hidden_undef-0x4
-
-0+1a <hidden_def>:
+[ ]*[a-f0-9]+: eb 21 jmp 23 <local>
+[ ]*[a-f0-9]+: eb 1b jmp 1f <hidden_def>
+[ ]*[a-f0-9]+: eb 1b jmp 21 <global_def>
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq b <foo\+0xb> 7: R_X86_64_PLT32 global_def-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 10 <foo\+0x10> c: R_X86_64_PC32 weak_def-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 15 <foo\+0x15> 11: R_X86_64_PC32 weak_hidden_undef-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 1a <foo\+0x1a> 16: R_X86_64_PC32 weak_hidden_def-0x4
+[ ]*[a-f0-9]+: e9 00 00 00 00 jmpq 1f <hidden_def> 1b: R_X86_64_PC32 hidden_undef-0x4
+
+0+1f <hidden_def>:
[ ]*[a-f0-9]+: c3 retq

-0+1b <weak_hidden_def>:
+0+20 <weak_hidden_def>:
[ ]*[a-f0-9]+: c3 retq

-0+1c <global_def>:
+0+21 <global_def>:
[ ]*[a-f0-9]+: c3 retq

-0+1d <weak_def>:
+0+22 <weak_def>:
[ ]*[a-f0-9]+: c3 retq

-0+1e <local>:
+0+23 <local>:
[ ]*[a-f0-9]+: c3 retq
#pass
--
1.9.3
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  Last update: 2015-05-13 02:21    [W:0.081 / U:0.128 seconds]
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