1 // { dg-do compile { target c++17_only } }
2 // { dg-options "-fconcepts-ts" }
5 concept bool C1 = __is_same_as(T, int);
8 concept bool C2 = N == 0;
10 template<template<typename> class X>
11 concept bool C3 = false;
13 template<typename> struct Foo;
15 // Instantiation of default arguments happens at the point of
16 // instantiation for the class.
18 template<C1 T = char> struct S1 { };
19 template<C2 N = 1> struct S2 { };
20 template<C3 X = Foo> struct S3 { };
22 S1<> s1; // { dg-error "constraint failure|invalid type" }
23 S2<> s2; // { dg-error "constraint failure|invalid type" }
24 S3<> s3; // { dg-error "constraint failure|invalid type" }