fail configure if you don't have a working c++ compiler

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@11603 d0543943-73ff-0310-b7d9-9358b9ac24b2

configure.in

@@ -53,6 +53,18 @@ AC_LANG_C
 # Checks for programs.
 AC_PROG_CC
 AC_PROG_CXX
+
+#check if the g++ compiler works
+AC_CACHE_CHECK([whether the C++ compiler works], [ac_cv_sys_cxx_works], [
+    AC_LANG_PUSH([C++])
+    AC_COMPILE_IFELSE([int main() { }], [ac_cv_sys_cxx_works=yes],
+        [ac_cv_sys_cxx_works=no])
+    AC_LANG_POP([C++])
+    ])
+[ if [ "x$ac_cv_sys_cxx_works" = "xno" ]; then ]
+    AC_MSG_FAILURE([The C++ compiler does not work. Please (re)install the C++ compiler])
+[ fi ]
+
 AC_PROG_AWK
 AC_PROG_MAKE_SET
 AC_PROG_INSTALL