It is well known that OS X < 10.9 uses obsolute gcc 4.2 based libstdc++ and not compatible with newer FSF libstdc++ (e.g. > 4.5) or libc++ by LLVM team.
It looks possible to use clang-3.3 with FSF’s libstdc++-4.8 and gcc-4.8 with libc++. I tested it with MacPorts currently. By using something like
g++-mp-4.8 -std=c++11 -nostdinc++ -isystem /opt/local/libexec/llvm-3.3/lib/c++/v1/ -lc++
clang++-mp-3.3 -nostdinc++ -cxx-isystem /opt/local/include/gcc48/c++/ \
-cxx-isystem /opt/local/include/gcc48/c++/x86_64-apple-darwin11/ -L/opt/local/lib/gcc48
std=c++11 is needed by g++ to parse libc++ while clang works in both 98 and 11 mode with FSF’s. The standard C++ including path used by gcc48 is
/opt/local/include/gcc48/c++/
/opt/local/include/gcc48/c++/x86_64-apple-darwin11
/opt/local/include/gcc48/c++/backward
In my previous command line, I omitted the backward directory for simplicity.
In general, mixing libc++ and libstdc++ will simply not link, but mixing old libstdc++ with new libstdc++ will cause crash.
It is unknown whether gcc compiled code with libc++ will crash when mixing clang compiled code with libc++.
Thanks
Yuuko PrZhu 03 December 2013