Make clang use libstdc++ from gcc package. In the future, the build of clang
could be parametrized to build clang with libstdc++ support or with libcxx
support.
* gnu/packages/llvm.scm (clang-from-llvm)[arguments]: Make clang look for
libstdc++ in the right location, which is gcc c++ includes directory.
Signed-off-by: Mathieu Othacehe <m.othacehe@gmail.com>
496bbeee7a