http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56637
--- Comment #5 from Fred Krogh <fkrogh#gcc at mathalacarte dot com> 2013-03-16 21:25:46 UTC --- I don't mean to be argumentative, but I would like to ask: Would an index out of bounds explain why single stepping over the statement make it work, and would it explain that a higher level of optimization works?