http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56888
Brooks Moses <brooks at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |brooks at gcc dot gnu.org --- Comment #10 from Brooks Moses <brooks at gcc dot gnu.org> --- FWIW, this issue also affected GLIBC. Pointer to discussion, along with fixes, here: http://sourceware.org/ml/libc-alpha/2013-07/msg00306.html It seems to me -- based on my own experience, as well as Max's -- that the -ftree-distribute-patterns documentation could be notably improved. In my case, I read it clearly and understood it to mean that it was only responsible for the loop-distribution portion of the rearrangement in the code examples, and that the replacement of a loop by a memcpy call was some other optimization pass. Other than the documentation issues, this seems like a non-bug.