https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80631
Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2017-05-04 CC| |alan.hayward at arm dot com, | |jakub at gcc dot gnu.org Target Milestone|--- |6.4 Summary|Compiling with -O3 -mavx2 |[6/7/8 Regression] |gives wrong code |Compiling with -O3 -mavx2 | |gives wrong code Ever confirmed|0 |1 --- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Started with r230297. Note, in C const int N = 8; int v[N]; is a variable length array, so unnecessarily pessimizing, you need to use #define N 8 or enum { N = 8 }; or something similar instead for it to be a non-VLA. In C++ it is not a VLA. But fixing that doesn't help here.