1// RUN: %clang_cc1 -fsyntax-only -verify %s -std=c++11
2
3struct DefaultedDefCtor1 {};
4struct DefaultedDefCtor2 { DefaultedDefCtor2() = default; };
5struct DeletedDefCtor { DeletedDefCtor() = delete; DeletedDefCtor(int); }; // expected-note {{explicitly marked deleted here}}
6class PrivateDefCtor { PrivateDefCtor() = default; public: PrivateDefCtor(int); };
7struct DeletedDtor { ~DeletedDtor() = delete; }; // expected-note 4{{explicitly marked deleted here}}
8class PrivateDtor { ~PrivateDtor() = default; };
9class Friend {
10  Friend() = default; ~Friend() = default;
11  friend struct NotDeleted6c;
12  friend struct NotDeleted7i;
13  friend struct NotDeleted7j;
14  friend struct NotDeleted7k;
15};
16struct UserProvidedDefCtor { UserProvidedDefCtor() {} };
17int n;
18
19
20// A defaulted default constructor for a class X is defined as deleted if:
21
22// - X is a union-like class that has a variant member with a non-trivial
23// default constructor,
24union Deleted1a { UserProvidedDefCtor u; }; // expected-note {{default constructor of 'Deleted1a' is implicitly deleted because variant field 'u' has a non-trivial default constructor}}
25Deleted1a d1a; // expected-error {{implicitly-deleted default constructor}}
26union NotDeleted1a { DefaultedDefCtor1 nu; };
27NotDeleted1a nd1a;
28union NotDeleted1b { DefaultedDefCtor2 nu; };
29NotDeleted1b nd1b;
30
31// - any non-static data member with no brace-or-equal-initializer is of
32// reference type,
33class Deleted2a {
34  Deleted2a() = default;  // expected-note 4{{implicitly deleted here}}
35  int &a; // expected-note 4{{because field 'a' of reference type 'int &' would not be initialized}}
36};
37Deleted2a d2a; // expected-error {{implicitly-deleted default constructor}}
38struct Deleted2b {
39  int &&b; // expected-note {{default constructor of 'Deleted2b' is implicitly deleted because field 'b' of reference type 'int &&' would not be initialized}}
40};
41Deleted2b d2b; // expected-error {{deleted default constructor}}
42class NotDeleted2a { int &a = n; };
43NotDeleted2a nd2a;
44class NotDeleted2b { int &a = error; }; // expected-error {{undeclared identifier}}
45NotDeleted2b nd2b;
46class NotDeleted2c { int &&a = 0; }; // expected-warning {{binding reference member 'a' to a temporary}} expected-note {{here}}
47NotDeleted2c nd2c;
48
49// - any non-variant non-static data member of const qualified type (or array
50// thereof) with no brace-or-equal-initializer does not have a user-provided
51// default constructor,
52class Deleted3a { const int a; }; // expected-note {{because field 'a' of const-qualified type 'const int' would not be initialized}} \
53                                     expected-warning {{does not declare any constructor}} \
54                                     expected-note {{will never be initialized}}
55Deleted3a d3a; // expected-error {{implicitly-deleted default constructor}}
56class Deleted3b { const DefaultedDefCtor1 a[42]; }; // expected-note {{because field 'a' of const-qualified type 'const DefaultedDefCtor1 [42]' would not be initialized}}
57Deleted3b d3b; // expected-error {{implicitly-deleted default constructor}}
58class Deleted3c { const DefaultedDefCtor2 a; }; // expected-note {{because field 'a' of const-qualified type 'const DefaultedDefCtor2' would not be initialized}}
59Deleted3c d3c; // expected-error {{implicitly-deleted default constructor}}
60class NotDeleted3a { const int a = 0; };
61NotDeleted3a nd3a;
62class NotDeleted3b { const DefaultedDefCtor1 a[42] = {}; };
63NotDeleted3b nd3b;
64class NotDeleted3c { const DefaultedDefCtor2 a = DefaultedDefCtor2(); };
65NotDeleted3c nd3c;
66union NotDeleted3d { const int a; int b; };
67NotDeleted3d nd3d;
68union NotDeleted3e { const DefaultedDefCtor1 a[42]; int b; };
69NotDeleted3e nd3e;
70union NotDeleted3f { const DefaultedDefCtor2 a; int b; };
71NotDeleted3f nd3f;
72struct NotDeleted3g { union { const int a; int b; }; };
73NotDeleted3g nd3g;
74
75// - X is a union and all of its variant members are of const-qualified type (or
76// array thereof),
77union Deleted4a {
78  const int a;
79  const int b;
80  const UserProvidedDefCtor c; // expected-note {{because variant field 'c' has a non-trivial default constructor}}
81};
82Deleted4a d4a; // expected-error {{implicitly-deleted default constructor}}
83union NotDeleted4a { const int a; int b; };
84NotDeleted4a nd4a;
85
86// - X is a non-union class and all members of any anonymous union member are of
87// const-qualified type (or array thereof),
88struct Deleted5a {
89  union { const int a; }; // expected-note {{because all data members of an anonymous union member are const-qualified}}
90  union { int b; };
91};
92Deleted5a d5a; // expected-error {{implicitly-deleted default constructor}}
93struct NotDeleted5a { union { const int a; int b; }; union { const int c; int d; }; };
94NotDeleted5a nd5a;
95
96// - any direct or virtual base class, or non-static data member with no
97// brace-or-equal-initializer, has class type M (or array thereof) and either
98// M has no default constructor or overload resolution as applied to M's default
99// constructor results in an ambiguity or in a function that is deleted or
100// inaccessible from the defaulted default constructor, or
101struct Deleted6a : Deleted2a {}; // expected-note {{because base class 'Deleted2a' has a deleted default constructor}}
102Deleted6a d6a; // expected-error {{implicitly-deleted default constructor}}
103struct Deleted6b : virtual Deleted2a {}; // expected-note {{because base class 'Deleted2a' has a deleted default constructor}}
104Deleted6b d6b; // expected-error {{implicitly-deleted default constructor}}
105struct Deleted6c { Deleted2a a; }; // expected-note {{because field 'a' has a deleted default constructor}}
106Deleted6c d6c; // expected-error {{implicitly-deleted default constructor}}
107struct Deleted6d { DeletedDefCtor a; }; // expected-note {{because field 'a' has a deleted default constructor}}
108Deleted6d d6d; // expected-error {{implicitly-deleted default constructor}}
109struct NotDeleted6a { DeletedDefCtor a = 0; };
110NotDeleted6a nd6a;
111struct Deleted6e { PrivateDefCtor a; }; // expected-note {{because field 'a' has an inaccessible default constructor}}
112Deleted6e d6e; // expected-error {{implicitly-deleted default constructor}}
113struct NotDeleted6b { PrivateDefCtor a = 0; };
114NotDeleted6b nd6b;
115struct NotDeleted6c { Friend a; };
116NotDeleted6c nd6c;
117
118// - any direct or virtual base class or non-static data member has a type with
119// a destructor that is deleted or inaccessible from the defaulted default
120// constructor.
121struct Deleted7a : DeletedDtor {}; // expected-note {{because base class 'DeletedDtor' has a deleted destructor}}
122Deleted7a d7a; // expected-error {{implicitly-deleted default constructor}}
123struct Deleted7b : virtual DeletedDtor {}; // expected-note {{because base class 'DeletedDtor' has a deleted destructor}}
124Deleted7b d7b; // expected-error {{implicitly-deleted default constructor}}
125struct Deleted7c { DeletedDtor a; }; // expected-note {{because field 'a' has a deleted destructor}}
126Deleted7c d7c; // expected-error {{implicitly-deleted default constructor}}
127struct Deleted7d { DeletedDtor a = {}; }; // expected-note {{because field 'a' has a deleted destructor}}
128Deleted7d d7d; // expected-error {{implicitly-deleted default constructor}}
129struct Deleted7e : PrivateDtor {}; // expected-note {{base class 'PrivateDtor' has an inaccessible destructor}}
130Deleted7e d7e; // expected-error {{implicitly-deleted default constructor}}
131struct Deleted7f : virtual PrivateDtor {}; // expected-note {{base class 'PrivateDtor' has an inaccessible destructor}}
132Deleted7f d7f; // expected-error {{implicitly-deleted default constructor}}
133struct Deleted7g { PrivateDtor a; }; // expected-note {{field 'a' has an inaccessible destructor}}
134Deleted7g d7g; // expected-error {{implicitly-deleted default constructor}}
135struct Deleted7h { PrivateDtor a = {}; }; // expected-note {{field 'a' has an inaccessible destructor}}
136Deleted7h d7h; // expected-error {{implicitly-deleted default constructor}}
137struct NotDeleted7i : Friend {};
138NotDeleted7i d7i;
139struct NotDeleted7j : virtual Friend {};
140NotDeleted7j d7j;
141struct NotDeleted7k { Friend a; };
142NotDeleted7k d7k;
143
144
145class Trivial { static const int n = 42; };
146static_assert(__has_trivial_constructor(Trivial), "Trivial is nontrivial");
147
148// A default constructor is trivial if it is not user-provided and if:
149class NonTrivialDefCtor1 { NonTrivialDefCtor1(); };
150static_assert(!__has_trivial_constructor(NonTrivialDefCtor1), "NonTrivialDefCtor1 is trivial");
151
152#define ASSERT_NONTRIVIAL_IMPL(Class, Bases, Body) \
153  class Class Bases { Body }; \
154  static_assert(!__has_trivial_constructor(Class), "");
155#define ASSERT_NONTRIVIAL(Class, Bases, Body) \
156  ASSERT_NONTRIVIAL_IMPL(Class, Bases, Body) \
157  ASSERT_NONTRIVIAL_IMPL(Def ## Class, Bases, Def ## Class() = default; Body) \
158  ASSERT_NONTRIVIAL_IMPL(Del ## Class, Bases, Del ## Class() = delete; Body)
159
160// - its class has no virtual functions (10.3) and no virtual base classes (10.1), and
161ASSERT_NONTRIVIAL(NonTrivialDefCtor2, , virtual void f();)
162ASSERT_NONTRIVIAL(NonTrivialDefCtor3, : virtual Trivial, )
163
164// - no non-static data member of its class has a brace-or-equal-initializer, and
165ASSERT_NONTRIVIAL(NonTrivialDefCtor4, , int m = 52;)
166
167// - all the direct base classes of its class have trivial default constructors, and
168ASSERT_NONTRIVIAL(NonTrivialDefCtor5, : NonTrivialDefCtor1, )
169
170// - for all the non-static data members of its class that are of class type (or array thereof), each such class
171// has a trivial default constructor.
172ASSERT_NONTRIVIAL(NonTrivialDefCtor6, , NonTrivialDefCtor1 t;)
173
174// FIXME: No core issue number yet.
175// - its parameter-declaration-clause is equivalent to that of an implicit declaration.
176struct NonTrivialDefCtor7 {
177  NonTrivialDefCtor7(...) = delete;
178};
179static_assert(!__has_trivial_constructor(NonTrivialDefCtor7), "");
180struct NonTrivialDefCtor8 {
181  NonTrivialDefCtor8(int = 0) = delete;
182};
183static_assert(!__has_trivial_constructor(NonTrivialDefCtor8), "");
184
185// Otherwise, the default constructor is non-trivial.
186
187class Trivial2 { Trivial2() = delete; };
188static_assert(__has_trivial_constructor(Trivial2), "Trivial2 is trivial");
189
190class Trivial3 { Trivial3() = default; };
191static_assert(__has_trivial_constructor(Trivial3), "Trivial3 is trivial");
192
193template<typename T> class Trivial4 { Trivial4() = default; };
194static_assert(__has_trivial_constructor(Trivial4<int>), "Trivial4 is trivial");
195
196template<typename T> class Trivial5 { Trivial5() = delete; };
197static_assert(__has_trivial_constructor(Trivial5<int>), "Trivial5 is trivial");
198
199namespace PR14558 {
200  // Ensure we determine whether an explicitly-defaulted or deleted special
201  // member is trivial before we return to parsing the containing class.
202  struct A {
203    struct B { B() = default; } b;
204    struct C { C() = delete; } c;
205  };
206
207  static_assert(__has_trivial_constructor(A), "");
208  static_assert(__has_trivial_constructor(A::B), "");
209}
210