On 1 April 2013 15:17, Vicente J. Botet Escriba wrote:
Hi,
it seems that gcc-4.8 doesn't defines any more __GXX_EXPERIMENTAL_CXX0X__ when the flag -std=c++11 is given.
Are you sure? The standard library no longer checks it, using __cplusplus >= 201103L instead, but the compiler still defines the old macro. The old macro is still documented as being defined.
This means that all the BOOST_NO_CXX11_ are defined.
Could something be done to make usable gcc-4.8 in c++11 mode?
You could check the value of __cplusplus instead, because __GXX_EXPERIMENTAL_CXX0X__ will stop being defined at some point eventually. A related topic I've been meaning to raise is that <boost/config/stdlib/libstdcpp3.hpp> unconditionally defines: // C++0x headers not yet (fully!) implemented // # define BOOST_NO_CXX11_HDR_THREAD This is incorrect. Depending on how GCC was configured libstdc++ has provided a complete <thread> since at least version 4.4, and for GCC 4.8 it unconditionally provides a complete <thread>. This should be correct: #if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 4) # define BOOST_NO_CXX11_HDR_THREAD #elif (__GNUC__ == 4 && __GNUC_MINOR__ < 8) # if !(defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) && defined(_GLIBCXX_USE_SCHED_YIELD) && defined(_GLIBCXX_USE_NANOSLEEP) && defined(__GXX_EXPERIMENTAL_CXX0X__)) # define BOOST_NO_CXX11_HDR_THREAD #elif __cplusplus < 201103L # define BOOST_NO_CXX11_HDR_THREAD #endif