diff --git a/C/dbase.c b/C/dbase.c
index 329d3adac..73d531875 100644
--- a/C/dbase.c
+++ b/C/dbase.c
@@ -2649,7 +2649,7 @@ new_lu_int_key(Int key)
   p->ArityOfPE = 3;
   p->OpcodeOfPred = Yap_opcode(_op_fail);
   p->cs.p_code.TrueCodeOfPred = p->CodeOfPred = FAILCODE;
-  WRITE_UNLOCK(ae->FRWLock);
+  WRITE_UNLOCK(ae->ARWLock);
   INT_LU_KEYS[hash_key] = p0;
   return p;
 }