[FFmpeg-devel] [PATCH] Fix link errors when HAVE_X86ASM is not defined

[James Almer]

On 11/21/2018 9:57 PM, Xiang, Haihao wrote:
> On Wed, 2018-11-21 at 12:27 -0300, James Almer wrote:
>> On 11/20/2018 11:47 PM, Haihao Xiang wrote:
>>> This fixes the link errors below:
>>>
>>> LD      ffmpeg_g
>>> libavfilter/libavfilter.so: undefined reference to `ff_scene_sad_avx2'
>>> libavfilter/libavfilter.so: undefined reference to `ff_scene_sad_sse2'
>>> collect2: error: ld returned 1 exit status
>>> Makefile:108: recipe for target 'ffmpeg_g' failed
>>> make: *** [ffmpeg_g] Error 1
>>>
>>> Signed-off-by: Haihao Xiang <haihao.xiang at intel.com>
>>> ---
>>>  libavfilter/x86/scene_sad_init.c | 10 ++++++++++
>>>  1 file changed, 10 insertions(+)
>>>
>>> diff --git a/libavfilter/x86/scene_sad_init.c
>>> b/libavfilter/x86/scene_sad_init.c
>>> index 461fa406d9..7e93ef44d3 100644
>>> --- a/libavfilter/x86/scene_sad_init.c
>>> +++ b/libavfilter/x86/scene_sad_init.c
>>> @@ -20,6 +20,7 @@
>>>  #include "libavutil/x86/cpu.h"
>>>  #include "libavfilter/scene_sad.h"
>>>  
>>> +#if HAVE_X86ASM
>>>  #define SCENE_SAD_FUNC(FUNC_NAME, ASM_FUNC_NAME,
>>> MMSIZE)                      \
>>>  void
>>> ASM_FUNC_NAME(SCENE_SAD_PARAMS);                                         \
>>>                                                                             
>>>    \
>>> @@ -50,3 +51,12 @@ ff_scene_sad_fn ff_scene_sad_get_fn_x86(int depth)
>>>      }
>>>      return NULL;
>>>  }
>>> +
>>> +#else
>>> +
>>> +ff_scene_sad_fn ff_scene_sad_get_fn_x86(int depth)
>>> +{
>>> +    return NULL;
>>> +}
>>> +
>>> +#endif
>>> \ No newline at end of file
>>
>> Can you test the attached patch? It's more in line with how other asm
>> modules with the same issue were fixed before, like synth_filter in
>> libavcodec.
> 
> Yes, your patch works for me. However I think you should check
> HAVE_AVX2_EXTERNAL as well in ff_scene_sad_get_fn_x86(), otherwise the link
> error still exists if HAVE_X86ASM is 1 but HAVE_AVX2_EXTERNAL is 0. Both
> HAVE_X86ASM and HAVE_AVX2_EXTERNAL are 0 on my system.

You're right, fixed and applied. Thanks.