https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117116
--- Comment #3 from Hongtao Liu <liuhongt at gcc dot gnu.org> --- A simple testcase typedef long long v4di __attribute__((vector_size(32))); v4di foo (long long a) { return __extension__(v4di){(long long)foo, 1, 1, 1}; } reproduced with -O2 -mavx2, failed at least since gcc4.8.1