Rollup merge of #69166 - JohnTitor:ice-const-enum, r=matthewjasper

Check `has_typeck_tables` before calling `typeck_tables_of`

Fixes #68684

r? @matthewjasper

src/test/ui/consts/issue-68684.rs

@@ -0,0 +1,15 @@
+// check-pass
+
+enum _Enum {
+    A(),
+}
+
+type _E = _Enum;
+
+const fn _a() -> _Enum {
+    _E::A()
+}
+
+const _A: _Enum = _a();
+
+fn main() {}