[Bug c/66740] omp simd reduction miscompiles at -O3 with AVX (recent regression)

[tprince at computer dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66740

--- Comment #1 from tprince at computer dot org ---
Created attachment 35898
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35898&action=edit
C source