Bug 664340 - Fallback to c++ when CXX is not set. r=khuey

build/autoconf/libstdcxx.py

@@ -67,7 +67,7 @@ def find_version(e):
     return encode_ver(last_version)
 
 if __name__ == '__main__':
-    cxx_env = os.environ['CXX']
+    cxx_env = os.environ.get('CXX', 'c++')
     print 'MOZ_LIBSTDCXX_TARGET_VERSION=%s' % find_version(cxx_env)
     host_cxx_env = os.environ.get('HOST_CXX', cxx_env)
     print 'MOZ_LIBSTDCXX_HOST_VERSION=%s' % find_version(host_cxx_env)

configure.in

@@ -7672,7 +7672,7 @@ MOZ_ARG_ENABLE_BOOL(stdcxx-compat,
 AC_SUBST(STDCXX_COMPAT)
 
 if test -n "$STDCXX_COMPAT"; then
-   eval $($_topsrcdir/build/autoconf/libstdcxx.py)
+   eval $($PYTHON $_topsrcdir/build/autoconf/libstdcxx.py)
    AC_SUBST(MOZ_LIBSTDCXX_TARGET_VERSION)
    AC_SUBST(MOZ_LIBSTDCXX_HOST_VERSION)
 fi