http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59934
--- Comment #9 from Jeffrey A. Law <law at redhat dot com> --- Jakub, I think your second approach is the better solution. It'll abort rather than silently returning a value which may or may not be appropriate in the caller's context. ie, returning 0 when we don't (for example) have partial modes may avoid this particular problem, but may cause issues elsewhere. Granted this code only has one user, but I'd rather play things like this defensively and just abort if we get into a situation that's not supposed to happen. I'll start an s390x build and see where the 2nd approach takes us...