Fix #113652. When calling `Node.isAggregate()` and `Node.isPOD()`, if `Node` is declared but not defined, it will result in null pointer dereference (and if assertions are enabled, it will cause an assertion failure).
Fix #113652. When calling `Node.isAggregate()` and `Node.isPOD()`, if `Node` is declared but not defined, it will result in null pointer dereference (and if assertions are enabled, it will cause an assertion failure).