1 // { dg-do compile { target c++11 } }
2 template<typename T> struct add_pointer;
3 template<typename T> struct add_reference;
4 
5 template<template<class T> class... Metafunctions>
6 struct metatuple {
7   static const int value = 0;
8 };
9 
10 template<>
11 struct metatuple<add_pointer> {
12   static const int value = 1;
13 };
14 
15 template<template<class T> class Meta>
16 struct metatuple<Meta, Meta> { // { dg-message "candidates" }
17   static const int value = 2;
18 };
19 
20 template<template<class T> class... Metafunctions>
21 struct metatuple<add_pointer, Metafunctions...> { // { dg-message "" }
22   static const int value = 3;
23 };
24 
25 template<template<class T> class First,
26          template<class T> class... Metafunctions>
27 struct metatuple<First, Metafunctions...> { // { dg-message "struct" }
28   static const int value = 4;
29 };
30 
31 template<template<class T> class First,
32          template<class T> class Second,
33          template<class T> class... Metafunctions>
34 struct metatuple<First, Second, Metafunctions...> { // { dg-message "struct" }
35   static const int value = 5;
36 };
37 
38 int a0[metatuple<>::value == 0? 1 : -1];
39 int a1[metatuple<add_pointer>::value == 1? 1 : -1];
40 int a2a[metatuple<add_pointer, add_pointer>::value == 2? 1 : -1]; // { dg-error "ambiguous|array bound" "bound" }
41 int a2b[metatuple<add_reference, add_reference>::value == 2? 1 : -1];
42 int a3[metatuple<add_pointer, add_reference>::value == 3? 1 : -1]; // { dg-error "ambiguous|array bound" "bound" }
43 int a4[metatuple<add_reference>::value == 4? 1 : -1];
44 int a5[metatuple<add_reference, add_pointer>::value == 5? 1 : -1];
45 
46 // { dg-error "incomplete" "incomplete" { target *-*-* } 40 }
47 // { dg-error "incomplete" "incomplete" { target *-*-* } 42 }
48