diff --git a/skeletons/constraints.c b/skeletons/constraints.c
index cf31706..5f01cc7 100644
--- a/skeletons/constraints.c
+++ b/skeletons/constraints.c
@@ -108,7 +108,7 @@
 	 */
 	len = ret + 1;
 	p = alloca(len);
-	if(!p) return;	/* Can't be though. */
+	if(!p) return;	/* Can fail on !x86. */
 
 	
 	va_start(ap, fmt);