AM_CONDITIONAL([CXX_WORKS], [test "x$rw_cv_prog_cxx_works" = "xyes"])
+# Check if the compiler support weak symbols
+AX_SYS_WEAK_ALIAS
+
+if test "x${ax_cv_sys_weak_alias}" = "xno"; then
+ AC_MSG_ERROR([Your platform doesn't support weak symbols.])
+fi
+
## Checks for libraries.
AC_CHECK_LIB([dl], [dlopen],
[