From b67c8ceb16c62f9328740e8ea0d851de966ac357 Mon Sep 17 00:00:00 2001
From: Slava Pestov <slava@factorcode.org>
Date: Tue, 10 Jan 2006 02:17:58 +0000
Subject: [PATCH] boxing a null pointer pushes f

---
 native/alien.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/native/alien.c b/native/alien.c
index ce78b6ecd7..022be5050a 100644
--- a/native/alien.c
+++ b/native/alien.c
@@ -59,9 +59,12 @@ ALIEN* alien(void* ptr)
 	return alien;
 }
 
-void box_alien(void* ptr)
+void box_alien(void *ptr)
 {
-	dpush(tag_object(alien(ptr)));
+	if(ptr == NULL)
+		dpush(F);
+	else
+		dpush(tag_object(alien(ptr)));
 }
 
 void primitive_alien(void)