http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48070
--- Comment #3 from Zdenek Sojka <zsojka at seznam dot cz> 2011-03-11 09:44:15 UTC --- (In reply to comment #2) > This is likely an unintelligent question, but does that output from valgrind > seem to indicate a code error or a compiler error? It can be either (in all cases, compiler error is very unlikely), but it gives a clue where you should have a look. Simple patch: struct Ray reflected; + reflected.shadowRay = 0; vector_copy( &hit->worldHit, &reflected.origin ); fixes the problem for me.