+# rw_PROG_CXX_WORKS
+# Check whether the C++ compiler works.
+AC_CACHE_CHECK([whether the C++ compiler works],
+ [rw_cv_prog_cxx_works],
+ [AC_LANG_PUSH([C++])
+ AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
+ [rw_cv_prog_cxx_works=yes],
+ [rw_cv_prog_cxx_works=no])
+ AC_LANG_POP([C++])])
+
+AM_CONDITIONAL([CXX_WORKS], [test "x$rw_cv_prog_cxx_works" = "xyes"])
+