diff --git a/jam/variable.c b/jam/variable.c
index 97b7bb067c..7a5b4f4442 100644
--- a/jam/variable.c
+++ b/jam/variable.c
@@ -118,7 +118,7 @@ var_defines( const char **e )
 		/* Get name */
 
 		if (val - *e > MAXSYM) {
-			printf("MAXSYM is too low, need at least %d\n", val - *e);
+			printf("MAXSYM is too low, need at least %td\n", val - *e);
 			exit(-1);
 		}
 		strncpy( buf, *e, val - *e );