When using clang-cl it expects parameters passed in MSVC-style, so appropriate toolchain should be selected.
As soon as both clang and clang-cl report themselfs as "clang" with -v option the only chance to detect
clang-cl is passing -? option to both which is valid for clang-cl.exe and not for clang.exe.
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>