Re: [PATCH] perf: fix building error in x86_64

Hekuang
2015-02-12T08:57:25Z

在 2015/2/12 16:07, Namhyung Kim 写道:
> Hi,
>
> On Wed, Feb 11, 2015 at 10:01:08AM +0800, He Kuang wrote:
>> When build with ARCH=x86_64, perf failed to compile with following error:
>>
>> tests/builtin-test.o:(.data+0x158): undefined reference to `test__perf_time_to_tsc'
>> collect2: error: ld returned 1 exit status
>> Makefile.perf:632: recipe for target 'perf' failed
>> ...
>>
>> Which is caused commit c6e5e9fbc3ea1 ("perf tools: Fix building error
>> in x86_64 when dwarf unwind is on"), ARCH test in Makefile.perf
>> conflicts with tests/builtin-test.c's __x86_64__.
>> To x86/x86_64 platform, ARCH should always override to x86 while
>> IS_64_BIT stands for the actual architecture.
>>
>> Signed-off-by: He Kuang <hekuang@huawei.com>
>> ---
>> tools/perf/config/Makefile.arch | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/tools/perf/config/Makefile.arch b/tools/perf/config/Makefile.arch
>> index ff95a68..8c6214d 100644
>> --- a/tools/perf/config/Makefile.arch
>> +++ b/tools/perf/config/Makefile.arch
>> @@ -14,7 +14,7 @@ ifeq ($(RAW_ARCH),i386)
>> endif
>>
>> ifeq ($(RAW_ARCH),x86_64)
>> - ARCH ?= x86
>> + override ARCH := x86
> Hmm.. wouldn't it (again) break cross build then?
>
> Thanks,
> Namhyung
>

I've tested both 'make ARCH=x86' and 'make ARCH=x86_64' cases after a
'make clean'.

The issue was first caused by IS_X86_64 flag wrongly cleared when
ARCH=x86, which is already fixed by separating IS_64_BIT and ARCH in
commit c6e5e9fbc3ea1 ("perf tools: Fix building error in x86_64 when
dwarf unwind is on").

The only problem here is we should let ARCH override to x86, to keep
compatible with 'ifeq ($(ARCH),x86)'.
>>
>> ifneq (, $(findstring m32,$(CFLAGS)))
>> RAW_ARCH := x86_32
>> --
>> 2.2.0.33.gc18b867
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at http://www.tux.org/lkml/
> .
>