1// RUN: %clang_cc1 -std=c++11 -verify %s
2
3// Check that we deal with cases where the instantiation of a class template
4// recursively requires the instantiation of the same template.
5namespace test1 {
6  template<typename T> struct A {
7    struct B { // expected-note {{not complete until the closing '}'}}
8      B b; // expected-error {{has incomplete type 'test1::A<int>::B'}}
9    };
10    B b; // expected-note {{in instantiation of}}
11  };
12  A<int> a; // expected-note {{in instantiation of}}
13}
14
15namespace test2 {
16  template<typename T> struct A {
17    struct B {
18      struct C {};
19      char c[1 + C()]; // expected-error {{invalid operands to binary expression}}
20      friend constexpr int operator+(int, C) { return 4; }
21    };
22    B b; // expected-note {{in instantiation of}}
23  };
24  A<int> a; // expected-note {{in instantiation of}}
25}
26
27namespace test3 {
28  // PR12317
29  template<typename T> struct A {
30    struct B {
31      enum { Val = 1 };
32      char c[1 + Val]; // ok
33    };
34    B b;
35  };
36  A<int> a;
37}
38
39namespace test4 {
40  template<typename T> struct M { typedef int type; };
41  template<typename T> struct A {
42    struct B { // expected-note {{not complete until the closing '}'}}
43      int k[typename A<typename M<T>::type>::B().k[0] + 1]; // expected-error {{incomplete type}}
44    };
45    B b; // expected-note {{in instantiation of}}
46  };
47  A<int> a; // expected-note {{in instantiation of}}
48}
49
50// FIXME: PR12298: Recursive constexpr function template instantiation leads to
51// stack overflow.
52#if 0
53namespace test5 {
54  template<typename T> struct A {
55    constexpr T f(T k) { return g(k); }
56    constexpr T g(T k) {
57      return k ? f(k-1)+1 : 0;
58    }
59  };
60  // This should be accepted.
61  constexpr int x = A<int>().f(5);
62}
63
64namespace test6 {
65  template<typename T> constexpr T f(T);
66  template<typename T> constexpr T g(T t) {
67    typedef int arr[f(T())];
68    return t;
69  }
70  template<typename T> constexpr T f(T t) {
71    typedef int arr[g(T())];
72    return t;
73  }
74  // This should be ill-formed.
75  int n = f(0);
76}
77
78namespace test7 {
79  template<typename T> constexpr T g(T t) {
80    return t;
81  }
82  template<typename T> constexpr T f(T t) {
83    typedef int arr[g(T())];
84    return t;
85  }
86  // This should be accepted.
87  int n = f(0);
88}
89#endif
90