Re: [PATCH, i386]: Additional fix for PR62599 with -mcmodel=medium -fpic
On Fri, May 13, 2016 at 7:20 PM, H.J. Lu wrote:
> On Fri, May 13, 2016 at 9:51 AM, Uros Bizjak wrote:
>> On Fri, May 13, 2016 at 9:07 AM, Uros Bizjak wrote:
>>> On Fri, May 13, 2016 at 1:20 AM, H.J. Lu wrote:
>>>
>> testsuite/gcc.target/i386/pr61599-{1,2}.c testcases expose a failure
>> with -mcmodel -fpic, where:
>>
>> /tmp/ccfpoxHY.o: In function `bar':
>> pr61599-2.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
>> against symbol `a' defined in LARGE_COMMON section in /tmp/ccKTKST2.o
>> collect2: error: ld returned 1 exit status
>> compiler exited with status 1
>>
>> CM_MEDIUM_PIC code model assumes that code+got/plt fits in a 31 bit
>> region, data is unlimited. Based on these assumptions, code should be
>> accessed via R_X86_64_GOT64.
>>
>> Attached patch uses UNSPEC_GOT instead of UNSPEC_GOTPCREL also for
>> CM_MEDIUM_PIC.
>>
>> 2016-05-12 Uros Bizjak
>>
>> PR target/61599
>> * config/i386/i386.c (legitimize_pic_address): Do not use
>> UNSPEC_GOTPCREL for CM_MEDIUM_PIC code model.
>>
>> Patch was bootstrapped on x86_64-linux-gnu and regression tested with
>> -mcmodel=medium -fpic.
>>
>> Jakub, H.J., do you have any comments on the patch?
>
>
> I prefer this patch.
>>
>>> Yes, your patch is more precise.
>>
>> OTOH, are we sure there is no linker bug here? We have:
>>
>> $ objdump -dr pr61599-1a.o
>>
>> pr61599-1a.o: file format elf64-x86-64
>>
>>
>> Disassembly of section .text:
>>
>> :
>>0: 55 push %rbp
>>1: 48 89 e5mov%rsp,%rbp
>>4: 48 8d 05 00 00 00 00lea0x0(%rip),%rax# b
>> 7: R_X86_64_GOTPC32 _GLOBAL_OFFSET_TABLE_-0x4
>>b: b8 00 00 00 00 mov$0x0,%eax
>> 10: e8 00 00 00 00 callq 15
>> 11: R_X86_64_PLT32 bar-0x4
>> 15: 89 c2 mov%eax,%edx
>> 17: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 1e
>> 1a: R_X86_64_GOTPCREL c-0x4
>> 1e: 0f b6 80 e1 00 00 00movzbl 0xe1(%rax),%eax
>> 25: 0f be c0movsbl %al,%eax
>> 28: 01 d0 add%edx,%eax
>> 2a: 5d pop%rbp
>> 2b: c3 retq
>>
>> $ objdump -dr pr61599-2a.o
>>
>> pr61599-2a.o: file format elf64-x86-64
>>
>>
>> Disassembly of section .text:
>>
>> :
>>0: 55 push %rbp
>>1: 48 89 e5mov%rsp,%rbp
>>4: 48 8d 05 00 00 00 00lea0x0(%rip),%rax# b
>> 7: R_X86_64_GOTPC32 _GLOBAL_OFFSET_TABLE_-0x4
>>b: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 12
>> e: R_X86_64_GOTPCRELa-0x4
>> 12: 0f b6 40 02 movzbl 0x2(%rax),%eax
>> 16: 0f be d0movsbl %al,%edx
>> 19: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 20
>> 1c: R_X86_64_GOTPCREL b-0x4
>> 20: 0f b6 40 10 movzbl 0x10(%rax),%eax
>> 24: 0f be c0movsbl %al,%eax
>> 27: 01 c2 add%eax,%edx
>> 29: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 30
>> 2c: R_X86_64_GOTPCREL c-0x4
>> 30: 0f b6 80 00 01 00 00movzbl 0x100(%rax),%eax
>> 37: 0f be c0movsbl %al,%eax
>> 3a: 01 d0 add%edx,%eax
>> 3c: 5d pop%rbp
>> 3d: c3 retq
>>
>> $ gcc pr61599-2a.o pr61599-1a.o
>> pr61599-2a.o: In function `bar':
>> pr61599-2a.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
>> against symbol `a' defined in LARGE_COMMON section in pr61599-1a.o
>> collect2: error: ld returned 1 exit status
>>
>> There is no R_X86_64_PC32 in pr61599-2a.o, only X86_64_GOTPCREL, which
>> according to assumptions, would reach all entries in the GOT table.
>
> I opened:
>
> https://sourceware.org/bugzilla/show_bug.cgi?id=20093
I also reported
https://sourceware.org/bugzilla/show_bug.cgi?id=20092
Thanks,
Uros.
Re: [PATCH, i386]: Additional fix for PR62599 with -mcmodel=medium -fpic
On Fri, May 13, 2016 at 9:51 AM, Uros Bizjak wrote:
> On Fri, May 13, 2016 at 9:07 AM, Uros Bizjak wrote:
>> On Fri, May 13, 2016 at 1:20 AM, H.J. Lu wrote:
>>
> testsuite/gcc.target/i386/pr61599-{1,2}.c testcases expose a failure
> with -mcmodel -fpic, where:
>
> /tmp/ccfpoxHY.o: In function `bar':
> pr61599-2.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
> against symbol `a' defined in LARGE_COMMON section in /tmp/ccKTKST2.o
> collect2: error: ld returned 1 exit status
> compiler exited with status 1
>
> CM_MEDIUM_PIC code model assumes that code+got/plt fits in a 31 bit
> region, data is unlimited. Based on these assumptions, code should be
> accessed via R_X86_64_GOT64.
>
> Attached patch uses UNSPEC_GOT instead of UNSPEC_GOTPCREL also for
> CM_MEDIUM_PIC.
>
> 2016-05-12 Uros Bizjak
>
> PR target/61599
> * config/i386/i386.c (legitimize_pic_address): Do not use
> UNSPEC_GOTPCREL for CM_MEDIUM_PIC code model.
>
> Patch was bootstrapped on x86_64-linux-gnu and regression tested with
> -mcmodel=medium -fpic.
>
> Jakub, H.J., do you have any comments on the patch?
I prefer this patch.
>
>> Yes, your patch is more precise.
>
> OTOH, are we sure there is no linker bug here? We have:
>
> $ objdump -dr pr61599-1a.o
>
> pr61599-1a.o: file format elf64-x86-64
>
>
> Disassembly of section .text:
>
> :
>0: 55 push %rbp
>1: 48 89 e5mov%rsp,%rbp
>4: 48 8d 05 00 00 00 00lea0x0(%rip),%rax# b
> 7: R_X86_64_GOTPC32 _GLOBAL_OFFSET_TABLE_-0x4
>b: b8 00 00 00 00 mov$0x0,%eax
> 10: e8 00 00 00 00 callq 15
> 11: R_X86_64_PLT32 bar-0x4
> 15: 89 c2 mov%eax,%edx
> 17: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 1e
> 1a: R_X86_64_GOTPCREL c-0x4
> 1e: 0f b6 80 e1 00 00 00movzbl 0xe1(%rax),%eax
> 25: 0f be c0movsbl %al,%eax
> 28: 01 d0 add%edx,%eax
> 2a: 5d pop%rbp
> 2b: c3 retq
>
> $ objdump -dr pr61599-2a.o
>
> pr61599-2a.o: file format elf64-x86-64
>
>
> Disassembly of section .text:
>
> :
>0: 55 push %rbp
>1: 48 89 e5mov%rsp,%rbp
>4: 48 8d 05 00 00 00 00lea0x0(%rip),%rax# b
> 7: R_X86_64_GOTPC32 _GLOBAL_OFFSET_TABLE_-0x4
>b: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 12
> e: R_X86_64_GOTPCRELa-0x4
> 12: 0f b6 40 02 movzbl 0x2(%rax),%eax
> 16: 0f be d0movsbl %al,%edx
> 19: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 20
> 1c: R_X86_64_GOTPCREL b-0x4
> 20: 0f b6 40 10 movzbl 0x10(%rax),%eax
> 24: 0f be c0movsbl %al,%eax
> 27: 01 c2 add%eax,%edx
> 29: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 30
> 2c: R_X86_64_GOTPCREL c-0x4
> 30: 0f b6 80 00 01 00 00movzbl 0x100(%rax),%eax
> 37: 0f be c0movsbl %al,%eax
> 3a: 01 d0 add%edx,%eax
> 3c: 5d pop%rbp
> 3d: c3 retq
>
> $ gcc pr61599-2a.o pr61599-1a.o
> pr61599-2a.o: In function `bar':
> pr61599-2a.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
> against symbol `a' defined in LARGE_COMMON section in pr61599-1a.o
> collect2: error: ld returned 1 exit status
>
> There is no R_X86_64_PC32 in pr61599-2a.o, only X86_64_GOTPCREL, which
> according to assumptions, would reach all entries in the GOT table.
I opened:
https://sourceware.org/bugzilla/show_bug.cgi?id=20093
--
H.J.
Re: [PATCH, i386]: Additional fix for PR62599 with -mcmodel=medium -fpic
On Fri, May 13, 2016 at 6:51 PM, Uros Bizjak wrote:
> On Fri, May 13, 2016 at 9:07 AM, Uros Bizjak wrote:
>> On Fri, May 13, 2016 at 1:20 AM, H.J. Lu wrote:
>>
> testsuite/gcc.target/i386/pr61599-{1,2}.c testcases expose a failure
> with -mcmodel -fpic, where:
>
> /tmp/ccfpoxHY.o: In function `bar':
> pr61599-2.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
> against symbol `a' defined in LARGE_COMMON section in /tmp/ccKTKST2.o
> collect2: error: ld returned 1 exit status
> compiler exited with status 1
>
> CM_MEDIUM_PIC code model assumes that code+got/plt fits in a 31 bit
> region, data is unlimited. Based on these assumptions, code should be
> accessed via R_X86_64_GOT64.
>
> Attached patch uses UNSPEC_GOT instead of UNSPEC_GOTPCREL also for
> CM_MEDIUM_PIC.
>
> 2016-05-12 Uros Bizjak
>
> PR target/61599
> * config/i386/i386.c (legitimize_pic_address): Do not use
> UNSPEC_GOTPCREL for CM_MEDIUM_PIC code model.
>
> Patch was bootstrapped on x86_64-linux-gnu and regression tested with
> -mcmodel=medium -fpic.
>
> Jakub, H.J., do you have any comments on the patch?
I prefer this patch.
>
>> Yes, your patch is more precise.
>
> OTOH, are we sure there is no linker bug here? We have:
>
> $ objdump -dr pr61599-1a.o
>
> pr61599-1a.o: file format elf64-x86-64
>
>
> Disassembly of section .text:
>
> :
>0: 55 push %rbp
>1: 48 89 e5mov%rsp,%rbp
>4: 48 8d 05 00 00 00 00lea0x0(%rip),%rax# b
> 7: R_X86_64_GOTPC32 _GLOBAL_OFFSET_TABLE_-0x4
>b: b8 00 00 00 00 mov$0x0,%eax
> 10: e8 00 00 00 00 callq 15
> 11: R_X86_64_PLT32 bar-0x4
> 15: 89 c2 mov%eax,%edx
> 17: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 1e
> 1a: R_X86_64_GOTPCREL c-0x4
> 1e: 0f b6 80 e1 00 00 00movzbl 0xe1(%rax),%eax
> 25: 0f be c0movsbl %al,%eax
> 28: 01 d0 add%edx,%eax
> 2a: 5d pop%rbp
> 2b: c3 retq
>
> $ objdump -dr pr61599-2a.o
>
> pr61599-2a.o: file format elf64-x86-64
>
>
> Disassembly of section .text:
>
> :
>0: 55 push %rbp
>1: 48 89 e5mov%rsp,%rbp
>4: 48 8d 05 00 00 00 00lea0x0(%rip),%rax# b
> 7: R_X86_64_GOTPC32 _GLOBAL_OFFSET_TABLE_-0x4
>b: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 12
> e: R_X86_64_GOTPCRELa-0x4
> 12: 0f b6 40 02 movzbl 0x2(%rax),%eax
> 16: 0f be d0movsbl %al,%edx
> 19: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 20
> 1c: R_X86_64_GOTPCREL b-0x4
> 20: 0f b6 40 10 movzbl 0x10(%rax),%eax
> 24: 0f be c0movsbl %al,%eax
> 27: 01 c2 add%eax,%edx
> 29: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 30
> 2c: R_X86_64_GOTPCREL c-0x4
> 30: 0f b6 80 00 01 00 00movzbl 0x100(%rax),%eax
> 37: 0f be c0movsbl %al,%eax
> 3a: 01 d0 add%edx,%eax
> 3c: 5d pop%rbp
> 3d: c3 retq
>
> $ gcc pr61599-2a.o pr61599-1a.o
> pr61599-2a.o: In function `bar':
> pr61599-2a.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
> against symbol `a' defined in LARGE_COMMON section in pr61599-1a.o
> collect2: error: ld returned 1 exit status
>
> There is no R_X86_64_PC32 in pr61599-2a.o, only X86_64_GOTPCREL, which
> according to assumptions, would reach all entries in the GOT table.
It is a bug in GNU linker:
$ gcc -fuse-ld=gold pr61599-2a.o pr61599-1a.o
$ ./a.out
Uros.
Re: [PATCH, i386]: Additional fix for PR62599 with -mcmodel=medium -fpic
On Fri, May 13, 2016 at 9:07 AM, Uros Bizjak wrote:
> On Fri, May 13, 2016 at 1:20 AM, H.J. Lu wrote:
>
testsuite/gcc.target/i386/pr61599-{1,2}.c testcases expose a failure
with -mcmodel -fpic, where:
/tmp/ccfpoxHY.o: In function `bar':
pr61599-2.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
against symbol `a' defined in LARGE_COMMON section in /tmp/ccKTKST2.o
collect2: error: ld returned 1 exit status
compiler exited with status 1
CM_MEDIUM_PIC code model assumes that code+got/plt fits in a 31 bit
region, data is unlimited. Based on these assumptions, code should be
accessed via R_X86_64_GOT64.
Attached patch uses UNSPEC_GOT instead of UNSPEC_GOTPCREL also for
CM_MEDIUM_PIC.
2016-05-12 Uros Bizjak
PR target/61599
* config/i386/i386.c (legitimize_pic_address): Do not use
UNSPEC_GOTPCREL for CM_MEDIUM_PIC code model.
Patch was bootstrapped on x86_64-linux-gnu and regression tested with
-mcmodel=medium -fpic.
Jakub, H.J., do you have any comments on the patch?
>>>
>>>
>>> I prefer this patch.
> Yes, your patch is more precise.
OTOH, are we sure there is no linker bug here? We have:
$ objdump -dr pr61599-1a.o
pr61599-1a.o: file format elf64-x86-64
Disassembly of section .text:
:
0: 55 push %rbp
1: 48 89 e5mov%rsp,%rbp
4: 48 8d 05 00 00 00 00lea0x0(%rip),%rax# b
7: R_X86_64_GOTPC32 _GLOBAL_OFFSET_TABLE_-0x4
b: b8 00 00 00 00 mov$0x0,%eax
10: e8 00 00 00 00 callq 15
11: R_X86_64_PLT32 bar-0x4
15: 89 c2 mov%eax,%edx
17: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 1e
1a: R_X86_64_GOTPCREL c-0x4
1e: 0f b6 80 e1 00 00 00movzbl 0xe1(%rax),%eax
25: 0f be c0movsbl %al,%eax
28: 01 d0 add%edx,%eax
2a: 5d pop%rbp
2b: c3 retq
$ objdump -dr pr61599-2a.o
pr61599-2a.o: file format elf64-x86-64
Disassembly of section .text:
:
0: 55 push %rbp
1: 48 89 e5mov%rsp,%rbp
4: 48 8d 05 00 00 00 00lea0x0(%rip),%rax# b
7: R_X86_64_GOTPC32 _GLOBAL_OFFSET_TABLE_-0x4
b: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 12
e: R_X86_64_GOTPCRELa-0x4
12: 0f b6 40 02 movzbl 0x2(%rax),%eax
16: 0f be d0movsbl %al,%edx
19: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 20
1c: R_X86_64_GOTPCREL b-0x4
20: 0f b6 40 10 movzbl 0x10(%rax),%eax
24: 0f be c0movsbl %al,%eax
27: 01 c2 add%eax,%edx
29: 48 8b 05 00 00 00 00mov0x0(%rip),%rax# 30
2c: R_X86_64_GOTPCREL c-0x4
30: 0f b6 80 00 01 00 00movzbl 0x100(%rax),%eax
37: 0f be c0movsbl %al,%eax
3a: 01 d0 add%edx,%eax
3c: 5d pop%rbp
3d: c3 retq
$ gcc pr61599-2a.o pr61599-1a.o
pr61599-2a.o: In function `bar':
pr61599-2a.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
against symbol `a' defined in LARGE_COMMON section in pr61599-1a.o
collect2: error: ld returned 1 exit status
There is no R_X86_64_PC32 in pr61599-2a.o, only X86_64_GOTPCREL, which
according to assumptions, would reach all entries in the GOT table.
Uros.
Re: [PATCH, i386]: Additional fix for PR62599 with -mcmodel=medium -fpic
On Fri, May 13, 2016 at 1:20 AM, H.J. Lu wrote:
>>> testsuite/gcc.target/i386/pr61599-{1,2}.c testcases expose a failure
>>> with -mcmodel -fpic, where:
>>>
>>> /tmp/ccfpoxHY.o: In function `bar':
>>> pr61599-2.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
>>> against symbol `a' defined in LARGE_COMMON section in /tmp/ccKTKST2.o
>>> collect2: error: ld returned 1 exit status
>>> compiler exited with status 1
>>>
>>> CM_MEDIUM_PIC code model assumes that code+got/plt fits in a 31 bit
>>> region, data is unlimited. Based on these assumptions, code should be
>>> accessed via R_X86_64_GOT64.
>>>
>>> Attached patch uses UNSPEC_GOT instead of UNSPEC_GOTPCREL also for
>>> CM_MEDIUM_PIC.
>>>
>>> 2016-05-12 Uros Bizjak
>>>
>>> PR target/61599
>>> * config/i386/i386.c (legitimize_pic_address): Do not use
>>> UNSPEC_GOTPCREL for CM_MEDIUM_PIC code model.
>>>
>>> Patch was bootstrapped on x86_64-linux-gnu and regression tested with
>>> -mcmodel=medium -fpic.
>>>
>>> Jakub, H.J., do you have any comments on the patch?
>>
>>
>> I prefer this patch.
>>
>
> Oops wrong one. Here is the right one.
Yes, your patch is more precise.
Thanks,
Uros.
Re: [PATCH, i386]: Additional fix for PR62599 with -mcmodel=medium -fpic
On Thu, May 12, 2016 at 4:19 PM, H.J. Lu wrote:
> On Thu, May 12, 2016 at 3:02 PM, Uros Bizjak wrote:
>> Hello!
>>
>> testsuite/gcc.target/i386/pr61599-{1,2}.c testcases expose a failure
>> with -mcmodel -fpic, where:
>>
>> /tmp/ccfpoxHY.o: In function `bar':
>> pr61599-2.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
>> against symbol `a' defined in LARGE_COMMON section in /tmp/ccKTKST2.o
>> collect2: error: ld returned 1 exit status
>> compiler exited with status 1
>>
>> CM_MEDIUM_PIC code model assumes that code+got/plt fits in a 31 bit
>> region, data is unlimited. Based on these assumptions, code should be
>> accessed via R_X86_64_GOT64.
>>
>> Attached patch uses UNSPEC_GOT instead of UNSPEC_GOTPCREL also for
>> CM_MEDIUM_PIC.
>>
>> 2016-05-12 Uros Bizjak
>>
>> PR target/61599
>> * config/i386/i386.c (legitimize_pic_address): Do not use
>> UNSPEC_GOTPCREL for CM_MEDIUM_PIC code model.
>>
>> Patch was bootstrapped on x86_64-linux-gnu and regression tested with
>> -mcmodel=medium -fpic.
>>
>> Jakub, H.J., do you have any comments on the patch?
>
>
> I prefer this patch.
>
Oops wrong one. Here is the right one.
--
H.J.
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 8157f9d..a864868 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -15478,7 +15478,9 @@ legitimize_pic_address (rtx orig, rtx reg)
new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_PCREL);
new_rtx = gen_rtx_CONST (Pmode, new_rtx);
}
- else if (TARGET_64BIT && ix86_cmodel != CM_LARGE_PIC)
+ else if (TARGET_64BIT
+ && ix86_cmodel != CM_LARGE_PIC
+ && !ix86_in_large_data_p (SYMBOL_REF_DECL (addr)))
{
new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr),
UNSPEC_GOTPCREL);
Re: [PATCH, i386]: Additional fix for PR62599 with -mcmodel=medium -fpic
On Thu, May 12, 2016 at 3:02 PM, Uros Bizjak wrote:
> Hello!
>
> testsuite/gcc.target/i386/pr61599-{1,2}.c testcases expose a failure
> with -mcmodel -fpic, where:
>
> /tmp/ccfpoxHY.o: In function `bar':
> pr61599-2.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
> against symbol `a' defined in LARGE_COMMON section in /tmp/ccKTKST2.o
> collect2: error: ld returned 1 exit status
> compiler exited with status 1
>
> CM_MEDIUM_PIC code model assumes that code+got/plt fits in a 31 bit
> region, data is unlimited. Based on these assumptions, code should be
> accessed via R_X86_64_GOT64.
>
> Attached patch uses UNSPEC_GOT instead of UNSPEC_GOTPCREL also for
> CM_MEDIUM_PIC.
>
> 2016-05-12 Uros Bizjak
>
> PR target/61599
> * config/i386/i386.c (legitimize_pic_address): Do not use
> UNSPEC_GOTPCREL for CM_MEDIUM_PIC code model.
>
> Patch was bootstrapped on x86_64-linux-gnu and regression tested with
> -mcmodel=medium -fpic.
>
> Jakub, H.J., do you have any comments on the patch?
I prefer this patch.
--
H.J.
diff --git a/ld/plugin.c b/ld/plugin.c
index bf66f52..01d76dd 100644
--- a/ld/plugin.c
+++ b/ld/plugin.c
@@ -674,7 +674,21 @@ get_symbols (const void *handle, int nsyms, struct ld_plugin_symbol *syms,
syms[n].name, FALSE, FALSE, TRUE);
if (!blhe)
{
- res = LDPR_UNKNOWN;
+ /* This symbol is defined and referenced only in IR. */
+ switch (syms[n].def)
+ {
+ default:
+ abort ();
+ case LDPK_UNDEF:
+ case LDPK_WEAKUNDEF:
+ res = LDPR_UNDEF;
+ break;
+ case LDPK_DEF:
+ case LDPK_WEAKDEF:
+ case LDPK_COMMON:
+ res = LDPR_PREVAILING_DEF_IRONLY;
+ break;
+ }
goto report_symbol;
}
[PATCH, i386]: Additional fix for PR62599 with -mcmodel=medium -fpic
Hello!
testsuite/gcc.target/i386/pr61599-{1,2}.c testcases expose a failure
with -mcmodel -fpic, where:
/tmp/ccfpoxHY.o: In function `bar':
pr61599-2.c:(.text+0xe): relocation truncated to fit: R_X86_64_PC32
against symbol `a' defined in LARGE_COMMON section in /tmp/ccKTKST2.o
collect2: error: ld returned 1 exit status
compiler exited with status 1
CM_MEDIUM_PIC code model assumes that code+got/plt fits in a 31 bit
region, data is unlimited. Based on these assumptions, code should be
accessed via R_X86_64_GOT64.
Attached patch uses UNSPEC_GOT instead of UNSPEC_GOTPCREL also for
CM_MEDIUM_PIC.
2016-05-12 Uros Bizjak
PR target/61599
* config/i386/i386.c (legitimize_pic_address): Do not use
UNSPEC_GOTPCREL for CM_MEDIUM_PIC code model.
Patch was bootstrapped on x86_64-linux-gnu and regression tested with
-mcmodel=medium -fpic.
Jakub, H.J., do you have any comments on the patch?
Uros.
Index: config/i386/i386.c
===
--- config/i386/i386.c (revision 236182)
+++ config/i386/i386.c (working copy)
@@ -15475,7 +15475,7 @@ legitimize_pic_address (rtx orig, rtx reg)
new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr), UNSPEC_PCREL);
new_rtx = gen_rtx_CONST (Pmode, new_rtx);
}
- else if (TARGET_64BIT && ix86_cmodel != CM_LARGE_PIC)
+ else if (TARGET_64BIT && ix86_cmodel == CM_SMALL_PIC)
{
new_rtx = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, addr),
UNSPEC_GOTPCREL);
