1 files changed, 2 insertions, 0 deletions
diff --git a/scripts/dev/gen_stub.php b/scripts/dev/gen_stub.php
index 2aed71af61..a02e23b256 100755
--- a/scripts/dev/gen_stub.php
+++ b/scripts/dev/gen_stub.php
@@ -108,6 +108,8 @@ class SimpleType {
     public function toTypeMask() {
         assert($this->isBuiltin);
         switch (strtolower($this->name)) {
+        case "null":
+            return "MAY_BE_NULL";
         case "false":
             return "MAY_BE_FALSE";
         case "bool":