http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59794
H.J. Lu <hjl.tools at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2014-01-13 Version|4.9.0 |4.7.0 Summary|i386 backend fails to |i386 backend fails to |detect SSE return value |detect SSE/AVX return value Ever confirmed|0 |1 --- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> --- The same problem with AVX for both -m32/-m64: [hjl@gnu-6 gcc]$ cat /tmp/a.i typedef long long __m256i __attribute__ ((__vector_size__ (32), __may_alias__)); extern __m256i y; __m256i f1() { return y; } [hjl@gnu-6 gcc]$ gcc -mno-avx /tmp/a.i -S -O [hjl@gnu-6 gcc]$ gcc -mno-avx /tmp/a.i -S -O -m32 [hjl@gnu-6 gcc]$