new file mode 100644
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+// PR c++/69694
+// { dg-do compile { target c++11 } }
+
+// n3911: TransformationTrait Alias `void_t`
+template<typename...> struct make_void { using type = void; };
+template<typename... Ts> using void_t = typename make_void<Ts...>::type;
+
+// std::declval<void*&>
+void*& declval_void();
+
+template<typename, typename = void> struct Fun;
+template<typename R>
+ struct Fun<R(), void>
+{
+ void fun();
+};
+template<typename Desc>
+ struct Fun<Desc, void_t<decltype (declval_void() = Desc::name)>>
+ : Fun<void()>
+{
+};
+
+struct Tag { static constexpr void* name = 0; };
+
+template<typename> void a()
+{
+ Fun<Tag>{}.fun();
+}
+
+void b() { a<int>(); }
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+// PR c++/69694
+// This is a reduced version of decltype74.C.
+// { dg-do compile { target c++11 } }
+
+template<typename... Ts> using void_t = void;
+
+extern void *declval_void;
+
+template<typename, typename> struct Fun { };
+
+template<typename Desc>
+struct Fun<Desc, void_t<decltype (declval_void = Desc::name)>>
+{
+ void fun();
+};
+
+struct Tag { static constexpr void* name = 0; };
+
+template<typename> void a()
+{
+ Fun<Tag, void>{}.fun();
+}
+
+void b() { a<int>(); }