From 2a63758b46a9f1b896e209a00b2f718ecd4a8b6f Mon Sep 17 00:00:00 2001
From: Keisuke Nishida <kxn30@po.cwru.edu>
Date: Fri, 20 Apr 2001 18:35:59 +0000
Subject: [PATCH] *** empty log message ***

---
 src/vm_system.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/vm_system.c b/src/vm_system.c
index 1fa3625f8..a8b887ea1 100644
--- a/src/vm_system.c
+++ b/src/vm_system.c
@@ -212,7 +212,11 @@ VM_DEFINE_INSTRUCTION (external_ref, "external-ref", 1, 0, 1)
   unsigned int i;
   SCM e = external;
   for (i = FETCH (); i; i--)
-    e = SCM_CDR (e);
+    {
+      CHECK_EXTERNAL(e);
+      e = SCM_CDR (e);
+    }
+  CHECK_EXTERNAL(e);
   PUSH (SCM_CAR (e));
   NEXT;
 }