Re: [Discuss-gnuradio] Volk build error using MacPorts GCC 4.7

[Michael Dickens]

Hi Nick - I'll also query the MacPorts developers with respect to this issue, 
to see if they can address it instead of GR folks trying to work around some 
Mac-specific idiosyncrasy.  Can you point me to a changelog or something 
equivalent which shows that AVX support is in the mainline GCC as of 4.4?  And, 
also, what exactly is AVX support in the first place?  I assume it's some 
variant on SIMD related to SSE1/2/3/4 or the like? - MLD

On Jan 24, 2013, at 1:13 PM, Nick Foster <address@hidden> wrote:
> This is a compiler problem. xgetbv was added to vanilla GCC in 4.4. 
> Apparently MacPorts' mutant GCC hasn't added it as of 4.7. The relevant check 
> is line 128 of volk/lib/CMakeLists.txt. We could just disable AVX support on 
> GCC < 4.7, but since 4.7 is basically the latest GCC out there it seems a 
> little aggressive to disable AVX for everyone. I'd rather disable AVX on Mac. 
> I haven't done Mac-specific platform detection in CMake; can anyone else 
> suggest a Mac test to use here to disable AVX on Mac?