http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51098
--- Comment #5 from Richard Henderson <rth at gcc dot gnu.org> 2011-11-14
23:50:59 UTC ---
... which will not be declared if AVX support is disavowed.
... except that the configure was --with-arch=corei7-avx.
If true, the problem is user error. How can you expect to
configure for corei7-avx without a working avx assembler?
Otherwise, we've mis-identified the assembler support and
this is a configure bug.
Only the reporter can tell us which of these alternatives hold.
---
I suppose we could change the configure check to be
#ifndef __AVX__
asm ("vzeroupper");
#endif
assuming that if --with-arch/CFLAGS says avx is present, believe it.
Let this fail later (again as user error) if the assembler can't
actually assemble AVX insns.
