http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50677
Richard Guenther <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2011-10-09 Ever Confirmed|0 |1 --- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-10-09 17:36:30 UTC --- Well, the issue is that most optimization passes just don't do anything for volatile qualified accesses. That's a safe thing. Deciding what kind of optimizations are allowed for volatile accesses might introduce bugs, and sofar the consensus was "volatile? don't bother with optimization, it'll be slow anyway". It very likely is combine that gives up here.