diff -Naurp cvs-1.12.13/diff/diff3.c cvs-1.12.13.oden/diff/diff3.c
--- cvs-1.12.13/diff/diff3.c	2004-10-09 17:51:52.000000000 +0200
+++ cvs-1.12.13.oden/diff/diff3.c	2008-12-20 15:19:10.000000000 +0100
@@ -1503,7 +1503,7 @@ output_diff3 (diff, mapping, rev_mapping
 	      line = 0;
 	      do
 		{
-		  printf_output (line_prefix);
+		  printf_output ("%s", line_prefix);
 		  cp = D_RELNUM (ptr, realfile, line);
 		  length = D_RELLEN (ptr, realfile, line);
 		  write_output (cp, length);
diff -Naurp cvs-1.12.13/src/main.c cvs-1.12.13.oden/src/main.c
--- cvs-1.12.13/src/main.c	2005-10-02 17:17:21.000000000 +0200
+++ cvs-1.12.13.oden/src/main.c	2008-12-20 15:19:10.000000000 +0100
@@ -1458,7 +1458,7 @@ usage (register const char *const *cpp)
 {
     (void) fprintf (stderr, *cpp++, program_name, cvs_cmd_name);
     for (; *cpp; cpp++)
-	(void) fprintf (stderr, *cpp);
+	(void) fprintf (stderr, "%s", *cpp);
     exit (EXIT_FAILURE);
 }