GitLab

On Mac OS 10.9, g++ is actually clang in disguise which by default uses the
new c++ standard library libc++. Since openfst uses stuff from the tr1
namespace, we need to tell clang to use libstdc++ instead. This patch adds a
check to the Makefile to see if we are using clang and adds the appropriate
flag if so.

With this patch, it is also possible to pass CXX, CXXFLAGS and LDFLAGS to make
while building the tools, e.g.

kaldi/tools ~ make CXX=g++-4.8 CXXFLAGS="-std=c++11" LDFLAGS="..."

git-svn-id: https://svn.code.sf.net/p/kaldi/code/sandbox/sail@3700 5e6a8d80-dfce-4ca6-a32a-6e07a63d50c8