http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53113
--- Comment #9 from Ryan Hill <dirtyepic at gentoo dot org> 2013-02-22 02:31:03 UTC --- Well, the trouble is nowadays that many CPUs are exactly "this, except without that". But anyways, the test is fragile. There is no reason something like -march=core2 -mno-sse3 should cause this to fail (I don't think it should even try to build it in the first place, but I'm sure there must be a reason). So if this code expects and requires -mavx to compile, append it after the user's CFLAGS rather than letting them blow their feet off.
