On Fr, 2016-08-26 at 21:45 +0300, Peter Dimov wrote:

André Draszik wrote:

...

Hi,

Is there any particular reason that boost isn't being compiled with  BOOST_AC_USE_STD_ATOMIC and BOOST_SP_USE_STD_ATOMIC (by default) when  C++11 support in g++ is available (g++ >= 4.7)?

Support for <atomic> in earlier C++11 implementations wasn't reliable enough  compared to shared_ptr's platform-specific implementations. Things nowadays have probably already reversed though, with <atomic> being  more reliable.

Thanks Peter.

I could turn it on by default when BOOST_NO_CXX11_HDR_ATOMIC  isn't defined,

Something like the attached?

which according to Boost.Config would enable it on g++ 4.9  and above. 

This would enable it on g++ >= 4.8 (not >= 4.9), though. https://github.com/boostorg/config/blob/develop/include/boost/config/stdlib/ libstdcpp3.hpp#L223 Cheers, Andre'

On Di, 2016-08-30 at 01:30 +0300, Peter Dimov wrote:

BOOST_SP_USE_STD_ATOMIC is a user macro that overrides the autodetection, so  Boost.Config shouldn't set it. 

I understand. Thanks! A.