LLVM Clang 6.0 Now Defaults To C++14

Up to now LLVM's Clang C/C++ compiler has defaulted to using C++98/GNU++98 as its default C++ standard, but fortunately that's no more.

Clang's default C++ dialect is now GNU++14 version of C++14 rather than GNU++98 (C++98).

The older versions of the C++ standard remain available and can be set via the -std= argument, just as those previously could have specified C++11 / C++14 / C++17, but now in cases where not specified, GNU++14/C++14 is the default.

The change is present in Clang 6.0 that will be released as stable in March while the feature freeze on this half-year LLVM/Clang update will go into feature freeze in January.

This C++14 as the default matches what GCC does currently for their default C++ standard when they switched from GNU++98 back in GCC 6. Matching GCC's behavior also explains why they didn't jump straight to the just-standardized C++17.