Hello ffmpeg developers, This commit [1] is causing problems when compiling with Clang on Windows:
..\..\third_party\ffmpeg\libavutil/x86/intmath.h(53,33) : error: always_inline function '__tzcnt_u32' requires target feature 'bmi', but would be inlined into function 'ff_ctzll_x86' that is compiled without support for 'bmi' return ((uint32_t)v == 0) ? _tzcnt_u32((uint32_t)(v >> 32)) + 32 : _tzcnt_u32((uint32_t)v); ^ Essentially the compiler is saying that it won't allow using this intrinsic unless compiling for a target that supports BMI. Is there a performance reason for using __tzcnt_u32 instead of _BitScanForward, or was it mainly to simplify the code? We're working around this in Chromium by #define'ing __tzcnt_u32 to __builtin_ctz at the moment, but it would be good if we could find a nicer solution that could be applied upstream. Cheers, Hans [1]. https://github.com/FFmpeg/FFmpeg/commit/6c6ac9cb17c4944514bde833f2fa8aa8dafa974a _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel