diff --git a/include/bits.c b/include/bits.c
index 84ab49de4..f390717fe 100644
--- a/include/bits.c
+++ b/include/bits.c
@@ -135,7 +135,7 @@ int main(int argc, char **argv)
 	f = fopen(argv[1], "w");
     }
     fprintf(f, "/* %s -- this file was generated for %s by\n", fn, HOST);
-    fprintf(f, "   %*s    %s */\n\n", strlen(fn), "", 
+    fprintf(f, "   %*s    %s */\n\n", (int)strlen(fn), "", 
 	    "$Id$");
     fprintf(f, "#ifndef %s\n", hb);
     fprintf(f, "#define %s\n", hb);