Fixed some compiler warnings on old gcc versions.
diff --git a/server/change.c b/server/change.c
index cef1c3e..4349d7e 100644
--- a/server/change.c
+++ b/server/change.c
@@ -942,7 +942,7 @@
     while (1)
     {
         buffer = malloc( n );
-        if (!buffer) break;
+        if (!buffer) return NULL;
 
         r = readlink( link, buffer, n );
         if (r < 0)