Homebrew/homebrew — pull request #33061 by jconley (2014-10-09 19:34:48+00:00)
Title: libvpx remove disable-runtime-cpu-detect

without runtime-cpu-detect, libvpx will use the compiler's supported optimizations, which may not exist on the cpu and cause a crash. confirmed this fix on #vp8 irc.
I personally experienced this trying to transcode video with ffmpeg to vp9 (this newer codec can use avx2 extensions, but they do not exist on my cpu [mid-2012 core i7])
also added head