diff --git a/servers/slapd/slap.h b/servers/slapd/slap.h
index 20c37414a3..1fb0207001 100644
--- a/servers/slapd/slap.h
+++ b/servers/slapd/slap.h
@@ -409,6 +409,7 @@ typedef struct slap_matching_rule {
 #define smr_extensions		smr_mrule.mr_extensions
 } MatchingRule;
 
+struct slap_backend_db;
 struct slap_entry;
 struct slap_attr;