1 // RUN: %clang_cc1 -fsyntax-only -std=c++11 -verify %s
2 template<typename T> struct X;
3 template<int I> struct Y;
4 
5 X<X<int>> *x1;
6 
7 Y<(1 >> 2)> *y1;
8 Y<1 >> 2> *y2; // FIXME: expected-error{{expected unqualified-id}}
9 
10 X<X<X<X<X<int>>>>> *x2;
11 
12 template<> struct X<int> { };
13 typedef X<int> X_int;
14 struct Z : X_int { };
15 
16 void f(const X<int> x) {
17   (void)reinterpret_cast<X<int>>(x); // expected-error{{reinterpret_cast from}}
18   (void)reinterpret_cast<X<X<X<int>>>>(x); // expected-error{{reinterpret_cast from}}
19 
20   X<X<int>> *x1;
21 }
22 
23 template<typename T = void> struct X1 { };
24 X1<X1<>> x1a;
25 
26 
27 namespace ParameterPackExpansions {
28 
29 // A template parameter pack that [contains an unexpanded parameter pack] is a
30 // pack expansion.
31 
32 template<typename...Ts> struct Outer {
33   // From [temp.variadic]p4:
34   //   In a template parameter pack that is a pack expansion, the pattern is
35   //   [...the template-parameter...] without the ellipsis.
36   // Therefore the resulting sequence of parameters is not a parameter pack,
37   // so is not required to be the last template parameter.
38   template<Ts ...As, template<Ts> class ...Bs, typename ...Cs> struct Inner {
39     struct Check : Bs<As>... {
40       Check(Cs...);
41     };
42   };
43 };
44 
45 template<int> struct TemplateInt {};
46 template<char> struct TemplateChar {};
47 template<int*> struct TemplateIntPtr {};
48 int x;
49 
50 Outer<int, char, int*>::
51 Inner<12345, 'x', &x,
52       TemplateInt, TemplateChar, TemplateIntPtr,
53       int*>::
54 Check check(&x);
55 
56 
57 template<typename...Ts> struct types;
58 
59 enum place { _ };
60 template<place...> struct places {};
61 
62 template<typename P1, typename P2> struct append_places;
63 template<place...X1, place...X2>
64 struct append_places<places<X1...>, places<X2...>> {
65   typedef places<X1...,X2...> type;
66 };
67 
68 template<unsigned N>
69 struct make_places : append_places<typename make_places<N/2>::type,
70                                    typename make_places<N-N/2>::type> {};
71 template<> struct make_places<0> { typedef places<> type; };
72 template<> struct make_places<1> { typedef places<_> type; };
73 
74 template<typename T> struct wrap {
75   template<place> struct inner { typedef T type; };
76 };
77 
78 template<typename T> struct takedrop_impl;
79 template<place...X> struct takedrop_impl<places<X...>> {
80   template<template<decltype(X)> class ...Take,
81            template<place      > class ...Drop>
82   struct inner { // expected-note 2{{declared}}
83     typedef types<typename Take<_>::type...> take;
84     typedef types<typename Drop<_>::type...> drop;
85   };
86 };
87 
88 template<unsigned N, typename...Ts> struct take {
89   using type = typename takedrop_impl<typename make_places<N>::type>::
90     template inner<wrap<Ts>::template inner...>::take; // expected-error {{too few template arguments}}
91 };
92 template<unsigned N, typename...Ts> struct drop {
93   using type = typename takedrop_impl<typename make_places<N>::type>::
94     template inner<wrap<Ts>::template inner...>::drop; // expected-error {{too few template arguments}}
95 };
96 
97 using T1 = take<3, int, char, double, long>::type; // expected-note {{previous}}
98 // FIXME: Desguar the types on the RHS in this diagnostic.
99 // desired-error {{'types<void, void, void, void>' vs 'types<int, char, double, (no argument)>'}}
100 using T1 = types<void, void, void, void>; // expected-error {{'types<void, void, void, void>' vs 'types<typename inner<_>::type, typename inner<_>::type, typename inner<_>::type, (no argument)>'}}
101 using D1 = drop<3, int, char, double, long>::type;
102 using D1 = types<long>;
103 
104 using T2 = take<4, int, char, double, long>::type; // expected-note {{previous}}
105 using T2 = types<int, char, double, long>;
106 // FIXME: Desguar the types on the RHS in this diagnostic.
107 // desired-error {{'types<void, void, void, void>' vs 'types<int, char, double, long>'}}
108 using T2 = types<void, void, void, void>; // expected-error {{'types<void, void, void, void>' vs 'types<typename inner<_>::type, typename inner<_>::type, typename inner<_>::type, typename inner<_>::type>'}}
109 using D2 = drop<4, int, char, double, long>::type;
110 using D2 = types<>;
111 
112 using T3 = take<5, int, char, double, long>::type; // expected-note {{in instantiation of}}
113 using D3 = drop<5, int, char, double, long>::type; // expected-note {{in instantiation of}}
114 
115 
116 // FIXME: We should accept this code. A parameter pack within a default argument
117 // in a template template parameter pack is expanded, because the pack is
118 // implicitly a pack expansion.
119 template<typename ...Default> struct DefArg {
120   template<template<typename T = Default> class ...Classes> struct Inner { // expected-error {{default argument contains unexpanded parameter pack}} expected-note {{here}}
121     Inner(Classes<>...); // expected-error {{too few}}
122   };
123 };
124 template<typename T> struct vector {};
125 template<typename T> struct list {};
126 vector<int> vi;
127 list<char> lc;
128 DefArg<int, char>::Inner<vector, list> defarg(vi, lc);
129 
130 
131 // FIXME:
132 // A template parameter pack that is a pack expansion shall not expand a
133 // parameter pack declared in the same template-parameter-list.
134 template<typename...Ts, Ts...Vs> void error(); // desired-error
135 
136 // This case should not produce an error, because in A's instantiation, Cs is
137 // not a parameter pack.
138 template<typename...Ts> void consume(Ts...);
139 template<typename...Ts> struct A {
140   template<template<typename, Ts = 0> class ...Cs, Cs<Ts> ...Vs> struct B { // ok
141     B() {
142       consume([]{
143         int arr[Vs]; // expected-error {{negative size}}
144       }...);
145     }
146   };
147 };
148 template<typename, int> using Int = int;
149 template<typename, short> using Char = char;
150 A<int, short>::B<Int, Char, -1, 'x'> b; // expected-note {{here}}
151 
152 }
153 
154 namespace PR9023 {
155   template<typename ...T> struct A {
156     template<template<T> class ...> struct B {
157     };
158   };
159 
160   template<int> struct C { };
161   template<long> struct D { };
162 
163   int main() {
164     A<int, long>::B<C, D> e;
165   }
166 }
167 
168 namespace std_examples {
169   template <class... Types> class Tuple;
170   template <class T, int... Dims> struct multi_array;
171   template <class... T> struct value_holder {
172     template<T... Values> struct apply { };
173   };
174   template <class... T, T... Values> struct static_array; // expected-error {{must be the last}}
175 
176   int n;
177   value_holder<int, char, int*>::apply<12345, 'x', &n> test;
178 }
179