From 661b650c1ab201898753116071387b41f070d48e Mon Sep 17 00:00:00 2001
From: Markus Armbruster <armbru@pond.sub.org>
Date: Sat, 19 Nov 2005 15:41:37 +0000
Subject: [PATCH] (ef_write): Don't memcpy() onto itself; behavior's undefined.

---
 src/lib/common/file.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/lib/common/file.c b/src/lib/common/file.c
index d710376e..fdba22b2 100644
--- a/src/lib/common/file.c
+++ b/src/lib/common/file.c
@@ -359,7 +359,8 @@ ef_write(int type, int id, void *from)
     if (id >= ep->baseid && id < ep->baseid + ep->cids) {
 	/* update the cache if necessary */
 	to = ep->cache + (id - ep->baseid) * ep->size;
-	memcpy(to, from, ep->size);
+	if (to != from)
+	    memcpy(to, from, ep->size);
     }
     if (id >= ep->fids) {
 	/* write beyond end of file extends it, take note */