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

[Hekuang <hekuang@huawei.com>]

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
>>
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> .
>