I have similar issues on gentoo building vlc-2.2.4 for qt-5.7.0 using gcc-5.4.0. either I get # error "Qt requires C++11 support" or, with --std=c++11 (and qt rebuilt as such) I get "atomic_compare_exchange_weak_explicit" passed 5 arguments, but takes just 4 How do I know if Qt a...