diff --git a/src/json.c b/src/json.c
index 0132df6..36d47aa 100644
--- a/src/json.c
+++ b/src/json.c
@@ -861,7 +861,7 @@
 	    break;
     }
 
-    if (res != NUL)
+    if (res != NULL)
     {
 	res->v_type = VAR_SPECIAL;
 	res->vval.v_number = VVAL_NONE;