On Sat, Oct 01, 2016 at 05:44:13PM +0200, wm4 wrote: > AFAIK most MMX code in FFmpeg does not run emms (i.e. keeps the FPU > state trashed) until returning to the API user. This means when malloc()/free()/... happens to be called internally, it corrupts the malloc structures, in a non-straightforward ways. Rune