diff --git a/servers/slapd/back-ldbm/alias.c b/servers/slapd/back-ldbm/alias.c
index 621f8c352793f0a2d692e302a3e7ca9a6d29f590..1d5a02484c5cca84e584935e1a9d4c2c66f0d5cb 100644
--- a/servers/slapd/back-ldbm/alias.c
+++ b/servers/slapd/back-ldbm/alias.c
@@ -12,7 +12,7 @@
 
 #include "portable.h"
 
-#ifndef SLAPD_ALIAS_DEREF
+#ifdef SLAPD_ALIAS_DEREF
 
 #include <stdio.h>
 #include <string.h>
@@ -246,4 +246,4 @@ char *derefDN ( Backend     *be,
   return newDN;
 }
 
-#endif SLAPD_ALIAS_DEREF
+#endif /* SLAPD_ALIAS_DEREF */