p6.cpp revision ef8225444452a1486bd721f3285301fe84643b00 
1ed07e00d438c74b7a23c01bfffde77e3968305e4Jeff Brown// RUN: %clang_cc1 -verify -std=c++11 %s
2
3namespace N {
4  typedef char C;
5}
6
7namespace M {
8  typedef double D;
9}
10
11struct NonLiteral {
12  NonLiteral() {}
13  NonLiteral(int) {} // expected-note 2{{here}}
14  operator int() const { return 0; }
15};
16struct Literal {
17  constexpr Literal() {}
18  operator int() const { return 0; }
19};
20
21struct S {
22  virtual int ImplicitlyVirtual() const;
23};
24struct T {};
25
26template<typename T> struct ImplicitVirtualFromDependentBase : T {
27  constexpr int ImplicitlyVirtual() const { return 0; }
28};
29
30constexpr int a = ImplicitVirtualFromDependentBase<S>().ImplicitlyVirtual(); // expected-error {{constant expression}} expected-note {{cannot evaluate virtual function call}}
31constexpr int b = ImplicitVirtualFromDependentBase<T>().ImplicitlyVirtual(); // ok
32constexpr int c = ImplicitVirtualFromDependentBase<S>().ImplicitVirtualFromDependentBase<S>::ImplicitlyVirtual();
33
34template<typename R> struct ConstexprMember {
35  constexpr R F() const { return 0; }
36};
37constexpr int d = ConstexprMember<int>().F(); // ok
38constexpr int e = ConstexprMember<NonLiteral>().F(); // expected-error {{constant expression}} expected-note {{non-literal type 'const NonLiteral' cannot be used in a constant expression}}
39
40template<typename ...P> struct ConstexprCtor {
41  constexpr ConstexprCtor(P...) {}
42};
43constexpr ConstexprCtor<> f1() { return {}; } // ok
44constexpr ConstexprCtor<int> f2() { return 0; } // ok
45constexpr ConstexprCtor<NonLiteral> f3() { return { 0 }; } // expected-error {{never produces a constant expression}} expected-note {{non-constexpr constructor 'NonLiteral}}
46constexpr ConstexprCtor<int, NonLiteral> f4() { return { 0, 0 }; } // expected-error {{never produces a constant expression}} expected-note {{non-constexpr constructor 'NonLiteral}}
47
48struct VirtBase : virtual S {}; // expected-note {{here}}
49
50namespace TemplateVBase {
51  template<typename T> struct T1 : virtual Literal { // expected-note {{here}}
52    constexpr T1() {} // expected-error {{constexpr constructor not allowed in struct with virtual base class}}
53  };
54
55  template<typename T> struct T2 : virtual T {
56    // FIXME: This is ill-formed (no diagnostic required).
57    // We should diagnose it now rather than waiting until instantiation.
58    constexpr T2() {}
59  };
60  constexpr T2<Literal> g2() { return {}; }
61
62  template<typename T> class T3 : public T { // expected-note {{class with virtual base class is not a literal type}}
63  public:
64    constexpr T3() {}
65  };
66  constexpr T3<Literal> g3() { return {}; } // ok
67  constexpr T3<VirtBase> g4() { return {}; } // expected-error {{not a literal type}}
68}
69