diff -u /home/amb/cxref/cpp/original/2.95.3/prefix.c /home/amb/cxref/cpp/prefix.c
--- /home/amb/cxref/cpp/original/2.95.3/prefix.c	1999-04-10 05:27:09.000000000 +0100
+++ /home/amb/cxref/cpp/prefix.c	2004-11-06 17:28:18.000000000 +0000
@@ -92,6 +92,8 @@
 # endif /* DIR_SEPARATOR && DIR_SEPARATOR_2 */
 #endif /* DIR_SEPARATOR */
 
+char * concat PROTO((const char *, ...)); /* Need prototype to remove compile warning - AMB */
+
 /* Given KEY, as above, return its value.  */
 
 static const char *