1 // RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify -fcxx-exceptions %s
2 
3 void fn() = default; // expected-error {{only special member}}
4 struct foo {
5   void fn() = default; // expected-error {{only special member}}
6 
7   foo() = default;
8   foo(const foo&) = default;
9   foo(foo&&) = default;
10   foo& operator = (const foo&) = default;
11   foo& operator = (foo&&) = default;
12   ~foo() = default;
13 };
14 
15 struct bar {
16   bar();
17   bar(const bar&);
18   bar(bar&&);
19   bar& operator = (const bar&);
20   bar& operator = (bar&&);
21   ~bar();
22 };
23 
24 bar::bar() = default;
25 bar::bar(const bar&) = default;
26 bar::bar(bar&&) = default;
27 bar& bar::operator = (const bar&) = default;
28 bar& bar::operator = (bar&&) = default;
29 bar::~bar() = default;
30 
31 static_assert(__is_trivial(foo), "foo should be trivial");
32 
33 static_assert(!__has_trivial_destructor(bar), "bar's destructor isn't trivial");
34 static_assert(!__has_trivial_constructor(bar),
35               "bar's default constructor isn't trivial");
36 static_assert(!__has_trivial_copy(bar), "bar has no trivial copy");
37 static_assert(!__has_trivial_assign(bar), "bar has no trivial assign");
38 
tester()39 void tester() {
40   foo f, g(f);
41   bar b, c(b);
42   f = g;
43   b = c;
44 }
45 
46 template<typename T> struct S : T {
47   constexpr S() = default;
48   constexpr S(const S&) = default;
49   constexpr S(S&&) = default;
50 };
litlit51 struct lit { constexpr lit() {} };
52 S<lit> s_lit; // ok
53 S<bar> s_bar; // ok
54 
55 struct Friends {
56   friend S<bar>::S();
57   friend S<bar>::S(const S&);
58   friend S<bar>::S(S&&);
59 };
60 
61 namespace DefaultedFnExceptionSpec {
62   // DR1330: The exception-specification of an implicitly-declared special
63   // member function is evaluated as needed.
64   template<typename T> T &&declval();
65   template<typename T> struct pair {
66     pair(const pair&) noexcept(noexcept(T(declval<T>())));
67   };
68 
69   struct Y;
70   struct X { X(); X(const Y&); };
71   struct Y { pair<X> p; };
72 
73   template<typename T>
74   struct A {
75     pair<T> p;
76   };
77   struct B {
78     B();
79     B(const A<B>&);
80   };
81 
82   // Don't crash here.
f()83   void f() {
84     X x = X();
85     (void)noexcept(B(declval<B>()));
86   }
87 
88   template<typename T>
89   struct Error {
90     void f() noexcept(T::error);
91 
92     Error() noexcept(T::error); // expected-error {{type 'int' cannot be used prior to '::' because it has no members}} expected-error {{type 'char'}}
93     Error(const Error&) noexcept(T::error); // expected-error {{type 'int' cannot be used prior to '::' because it has no members}}
94     Error(Error&&) noexcept(T::error); // expected-error {{type 'int' cannot be used prior to '::' because it has no members}}
95     Error &operator=(const Error&) noexcept(T::error); // expected-error {{type 'int' cannot be used prior to '::' because it has no members}} expected-error {{type 'double'}}
96     Error &operator=(Error&&) noexcept(T::error); // expected-error {{type 'int' cannot be used prior to '::' because it has no members}}
97     ~Error() noexcept(T::error); // expected-error {{type 'int' cannot be used prior to '::' because it has no members}} expected-error {{type 'char'}}
98   };
99 
100   Error<char> c; // expected-note 2{{instantiation of}}
101   struct DelayImplicit {
102     // FIXME: The location of this note is terrible. The instantiation was
103     // triggered by the uses of the functions in the decltype expressions below.
104     Error<int> e; // expected-note 6{{instantiation of}}
105   };
106   Error<float> *e;
107 
108   // An exception specification is needed if the exception specification for a
109   // a defaulted special member function that calls the function is needed.
110   // Use in an unevaluated operand still results in the exception spec being
111   // needed.
112   void test1(decltype(declval<DelayImplicit>() = DelayImplicit(DelayImplicit())));
113   void test2(decltype(declval<DelayImplicit>() = declval<const DelayImplicit>()));
114   void test3(decltype(DelayImplicit(declval<const DelayImplicit>())));
115 
116   // Any odr-use needs the exception specification.
f(Error<double> * p)117   void f(Error<double> *p) {
118     *p = *p; // expected-note {{instantiation of}}
119   }
120 }
121 
122 namespace PR13527 {
123   struct X {
124     X() = delete; // expected-note {{here}}
125     X(const X&) = delete; // expected-note {{here}}
126     X(X&&) = delete; // expected-note {{here}}
127     X &operator=(const X&) = delete; // expected-note {{here}}
128     X &operator=(X&&) = delete; // expected-note {{here}}
129     ~X() = delete; // expected-note {{here}}
130   };
131   X::X() = default; // expected-error {{redefinition}}
132   X::X(const X&) = default; // expected-error {{redefinition}}
133   X::X(X&&) = default; // expected-error {{redefinition}}
134   X &X::operator=(const X&) = default; // expected-error {{redefinition}}
135   X &X::operator=(X&&) = default; // expected-error {{redefinition}}
136   X::~X() = default; // expected-error {{redefinition}}
137 
138   struct Y {
139     Y() = default;
140     Y(const Y&) = default;
141     Y(Y&&) = default;
142     Y &operator=(const Y&) = default;
143     Y &operator=(Y&&) = default;
144     ~Y() = default;
145   };
146   Y::Y() noexcept = default; // expected-error {{definition of explicitly defaulted}}
147   Y::Y(const Y&) noexcept = default; // expected-error {{definition of explicitly defaulted}}
148   Y::Y(Y&&) noexcept = default; // expected-error {{definition of explicitly defaulted}}
149   Y &Y::operator=(const Y&) noexcept = default; // expected-error {{definition of explicitly defaulted}}
150   Y &Y::operator=(Y&&) noexcept = default; // expected-error {{definition of explicitly defaulted}}
151   Y::~Y() = default; // expected-error {{definition of explicitly defaulted}}
152 }
153 
154 namespace PR27699 {
155   struct X {
156     X();
157   };
158   X::X() = default; // expected-note {{here}}
159   X::X() = default; // expected-error {{redefinition of 'X'}}
160 }
161 
162 namespace PR14577 {
163   template<typename T>
164   struct Outer {
165     template<typename U>
166     struct Inner1 {
167       ~Inner1();
168     };
169 
170     template<typename U>
171     struct Inner2 {
172       ~Inner2();
173     };
174   };
175 
176   template<typename T>
177   Outer<T>::Inner1<T>::~Inner1() = delete; // expected-error {{nested name specifier 'Outer<T>::Inner1<T>::' for declaration does not refer into a class, class template or class template partial specialization}}  expected-error {{only functions can have deleted definitions}}
178 
179   template<typename T>
180   Outer<T>::Inner2<T>::~Inner2() = default; // expected-error {{nested name specifier 'Outer<T>::Inner2<T>::' for declaration does not refer into a class, class template or class template partial specialization}}  expected-error {{only special member functions may be defaulted}}
181 }
182 
183 extern "C" { // expected-note {{extern "C" language linkage specification begins here}}
184  template<typename _Tp> // expected-error {{templates must have C++ linkage}}
185  void PR13573(const _Tp&) = delete;
186 }
187 
188 namespace PR15597 {
189   template<typename T> struct A {
190     A() noexcept(true) = default;
191     ~A() noexcept(true) = default;
192   };
193   template<typename T> struct B {
194     B() noexcept(false) = default; // expected-error {{does not match the calculated one}}
195     ~B() noexcept(false) = default; // expected-error {{does not match the calculated one}}
196   };
197   A<int> a;
198   B<int> b; // expected-note {{here}}
199 }
200 
201 namespace PR27941 {
202 struct ExplicitBool {
203   ExplicitBool &operator=(bool) = default; // expected-error{{only special member functions may be defaulted}}
204   int member;
205 };
206 
fn()207 int fn() {
208   ExplicitBool t;
209   t = true;
210 }
211 }
212 
213 namespace dependent_classes {
214 template <bool B, typename X, typename Y>
215 struct conditional;
216 
217 template <typename X, typename Y>
218 struct conditional<true, X, Y> { typedef X type; };
219 
220 template <typename X, typename Y>
221 struct conditional<false, X, Y> { typedef Y type; };
222 
223 template<bool B> struct X {
224   X();
225 
226   // B == false triggers error for = default.
227   using T = typename conditional<B, const X &, int>::type;
228   X(T) = default;  // expected-error {{only special member functions}}
229 
230   // Either value of B creates a constructor that can be default
231   using U = typename conditional<B, X&&, const X&>::type;
232   X(U) = default;
233 };
234 
235 X<true> x1;
236 X<false> x2; // expected-note {{in instantiation}}
237 
238 template <typename Type>
239 class E {
240   explicit E(const int &) = default;
241 };
242 
243 template <typename Type>
E(const int &)244 E<Type>::E(const int&) {}  // expected-error {{definition of explicitly defaulted function}}
245 
246 }
247