Ryan Hill wrote: > On Mon, 28 Sep 2009 16:41:57 -0700 > Corey Hickey <bugfood-ml@xxxxxxxxxx> wrote: > >> Hello, >> >> I'm running into a segfault with MPlayer on MKV files. I think it might >> be a bug in some aspect of GCC 4.4's optimization, but I'm having >> trouble narrowing it down. All I know for sure is: >> >> Works: >> * compiled by gcc 4.4 with -O2 >> * compiled by gcc 3.3, 3.4, 4.0, 4.1, 4.2, 4.3 (any optimization level) >> * compiled by gcc svn trunk (any optimization level) >> >> Crashes: >> * compiled by gcc 4.4 with -O3 > > We've seen the same problem and I think it was narrowed down to > -finline-functions. See http://bugs.gentoo.org/269975. Unfortunately the > rest of the bug report is just noise. Good luck! Thanks. I ran across that bug report several days ago but hadn't seen the note about -finline-functions. Yet, I think my report has a bit more information, at least as it pertains to the behavior I'm seeing: removing -finline-functions indeed makes the segfault go away, but so does removing any one of these flags: -O1 -fgcse -finline-small-functions -fschedule-insns2 -fstrict-aliasing -finline-functions All of the above have to be present to cause the crash to occur. Also of interest is that I can compile the rest of MPlayer without any optimization (except for libswscale/swcale.c, which needs -O1 to compile). I can then compile demux_mkv.c with the set of flags above to cause the crash to occur. From within mplayer source tree: gcc-4.4 -g -I. -c -o libmpdemux/demux_mkv.o libmpdemux/demux_mkv.c -O1 -fgcse -finline-small-functions -fschedule-insns2 -fstrict-aliasing -finline-functions && make Thanks, Corey
