--- aclang.m4.org	Tue May  7 08:27:48 2002
+++ aclang.m4	Tue May  7 09:44:26 2002
@@ -402,6 +402,10 @@
 /* We use char because int might match the return type of a gcc2
    builtin and then its argument prototype would still apply.  */
 char $1 ();
+#ifdef __cplusplus
+extern "C"
+char (*f) ();
+#endif
 char (*f) ();
 ],
 [/* The GNU C library defines this for functions which it implements