PR c++/85228 - ICE with lambda in enumerator.

	* pt.c (bt_instantiate_type_proc): Don't assume
	CLASSTYPE_TEMPLATE_INFO is non-null.

From-SVN: r259130

gcc/cp/ChangeLog

+2018-04-05  Jason Merrill  <jason@redhat.com>
+
+	PR c++/85228 - ICE with lambda in enumerator in template.
+	* pt.c (bt_instantiate_type_proc): Don't assume
+	CLASSTYPE_TEMPLATE_INFO is non-null.
+
 2018-04-05  Ville Voutilainen  <ville.voutilainen@gmail.com>
 
 	Implement P0969

gcc/cp/pt.c

@@ -22841,6 +22841,7 @@ bt_instantiate_type_proc (binding_entry entry, void *data)
   tree storage = *(tree *) data;
 
   if (MAYBE_CLASS_TYPE_P (entry->type)
+      && CLASSTYPE_TEMPLATE_INFO (entry->type)
       && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
     do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
 }

gcc/testsuite/g++.dg/cpp1z/constexpr-lambda21.C

+// PR c++/85228
+// { dg-additional-options -std=c++17 }
+
+template<int> struct A
+{
+  enum E { e = []{ return 0; }() };
+};
+
+template class A<0>;