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      1 // RUN: %clang_cc1 -fsyntax-only -verify %s
      2 
      3 void abort() __attribute__((noreturn));
      4 
      5 class Okay {
      6   int a_;
      7 };
      8 
      9 class Virtual {
     10   virtual void foo() { abort(); } // expected-note 4 {{because type 'Virtual' has a virtual member function}}
     11 };
     12 
     13 class VirtualBase : virtual Okay { // expected-note 4 {{because type 'VirtualBase' has a virtual base class}}
     14 };
     15 
     16 class Ctor {
     17   Ctor() { abort(); } // expected-note 2{{because type 'Ctor' has a user-provided default constructor}} expected-note 2{{here}}
     18 };
     19 class Ctor2 {
     20   Ctor2(); // expected-note {{because type 'Ctor2' has a user-provided default constructor}} expected-note 2{{here}}
     21 };
     22 class CtorTmpl { // expected-note {{because type 'CtorTmpl' has no default constructor}}
     23   template<typename T> CtorTmpl(); // expected-note {{implicit default constructor suppressed by user-declared constructor}}
     24 };
     25 
     26 class CopyCtor { // expected-note 2{{because no constructor can be used to copy an object of type 'const CopyCtor'}}
     27   CopyCtor(CopyCtor &cc) { abort(); }
     28 };
     29 
     30 class CopyAssign { // expected-note 2 {{because no assignment operator can be used to copy an object of type 'const CopyAssign'}}
     31   CopyAssign& operator=(CopyAssign& CA) { abort(); }
     32 };
     33 
     34 class Dtor {
     35   ~Dtor() { abort(); } // expected-note 2 {{because type 'Dtor' has a user-provided destructor}} expected-note 2{{here}}
     36 };
     37 
     38 union U1 {
     39   Virtual v; // expected-error {{union member 'v' has a non-trivial copy constructor}}
     40   VirtualBase vbase; // expected-error {{union member 'vbase' has a non-trivial copy constructor}}
     41   Ctor ctor; // expected-error {{union member 'ctor' has a non-trivial constructor}}
     42   Ctor2 ctor2; // expected-error {{union member 'ctor2' has a non-trivial constructor}}
     43   CtorTmpl ctortmpl; // expected-error {{union member 'ctortmpl' has a non-trivial constructor}}
     44   CopyCtor copyctor; // expected-error {{union member 'copyctor' has a non-trivial copy constructor}}
     45   CopyAssign copyassign; // expected-error {{union member 'copyassign' has a non-trivial copy assignment operator}}
     46   Dtor dtor; // expected-error {{union member 'dtor' has a non-trivial destructor}}
     47   Okay okay;
     48 };
     49 
     50 union U2 {
     51   struct {
     52     Virtual v; // expected-note {{because the function selected to copy field of type 'Virtual' is not trivial}}
     53   } m1; // expected-error {{union member 'm1' has a non-trivial copy constructor}}
     54   struct {
     55     VirtualBase vbase; // expected-note {{because the function selected to copy field of type 'VirtualBase' is not trivial}}
     56   } m2; // expected-error {{union member 'm2' has a non-trivial copy constructor}}
     57   struct {
     58     Ctor ctor; // expected-note {{because field of type 'Ctor' has a user-provided default constructor}}
     59   } m3; // expected-error {{union member 'm3' has a non-trivial constructor}}
     60   struct {
     61     Ctor2 ctor2; // expected-note {{because field of type 'Ctor2' has a user-provided default constructor}}
     62   } m3a; // expected-error {{union member 'm3a' has a non-trivial constructor}}
     63   struct { // expected-note {{no constructor can be used to copy an object of type 'const}}
     64     CopyCtor copyctor;
     65   } m4; // expected-error {{union member 'm4' has a non-trivial copy constructor}}
     66   struct { // expected-note {{no assignment operator can be used to copy an object of type 'const}}
     67     CopyAssign copyassign;
     68   } m5; // expected-error {{union member 'm5' has a non-trivial copy assignment operator}}
     69   struct {
     70     Dtor dtor; // expected-note {{because field of type 'Dtor' has a user-provided destructor}}
     71   } m6; // expected-error {{union member 'm6' has a non-trivial destructor}}
     72   struct {
     73     Okay okay;
     74   } m7;
     75 };
     76 
     77 union U3 {
     78   struct s1 : Virtual { // expected-note {{because the function selected to copy base class of type 'Virtual' is not trivial}}
     79   } m1; // expected-error {{union member 'm1' has a non-trivial copy constructor}}
     80   struct s2 : VirtualBase { // expected-note {{because the function selected to copy base class of type 'VirtualBase' is not trivial}}
     81   } m2; // expected-error {{union member 'm2' has a non-trivial copy constructor}}
     82   struct s3 : Ctor { // expected-note {{because base class of type 'Ctor' has a user-provided default constructor}}
     83   } m3; // expected-error {{union member 'm3' has a non-trivial constructor}}
     84   struct s3a : Ctor2 { // expected-note {{because base class of type 'Ctor2' has a user-provided default constructor}}
     85   } m3a; // expected-error {{union member 'm3a' has a non-trivial constructor}}
     86   struct s4 : CopyCtor { // expected-note {{because no constructor can be used to copy an object of type 'const U3::s4'}}
     87   } m4; // expected-error {{union member 'm4' has a non-trivial copy constructor}}
     88   struct s5 : CopyAssign { // expected-note {{because no assignment operator can be used to copy an object of type 'const U3::s5'}}
     89   } m5; // expected-error {{union member 'm5' has a non-trivial copy assignment operator}}
     90   struct s6 : Dtor { // expected-note {{because base class of type 'Dtor' has a user-provided destructor}}
     91   } m6; // expected-error {{union member 'm6' has a non-trivial destructor}}
     92   struct s7 : Okay {
     93   } m7;
     94   struct s8 {
     95     s8(...) = delete; // expected-note {{because it is a variadic function}} expected-warning {{C++11}}
     96   } m8; // expected-error {{union member 'm8' has a non-trivial constructor}}
     97 };
     98 
     99 union U4 {
    100   static int i1; // expected-warning {{static data member 'i1' in union is a C++11 extension}}
    101 };
    102 int U4::i1 = 10;
    103 
    104 union U5 {
    105   int& i1; // expected-error {{union member 'i1' has reference type 'int &'}}
    106 };
    107 
    108 union U6 {
    109   struct S {
    110     int &i;
    111   } s; // ok
    112 };
    113 
    114 template <class A, class B> struct Either {
    115   bool tag;
    116   union { // expected-note 6 {{in instantiation of member class}}
    117     A a;
    118     B b; // expected-error 6 {{non-trivial}}
    119   };
    120 
    121   Either(const A& a) : tag(true), a(a) {}
    122   Either(const B& b) : tag(false), b(b) {}
    123 };
    124 
    125 void fred() {
    126   Either<int,Virtual> virt(0); // expected-note {{in instantiation of template}}
    127   Either<int,VirtualBase> vbase(0); // expected-note {{in instantiation of template}}
    128   Either<int,Ctor> ctor(0); // expected-note {{in instantiation of template}}
    129   Either<int,CopyCtor> copyctor(0); // expected-note {{in instantiation of template}}
    130   Either<int,CopyAssign> copyassign(0); // expected-note {{in instantiation of template}}
    131   Either<int,Dtor> dtor(0); // expected-note {{in instantiation of template}}
    132   Either<int,Okay> okay(0);
    133 }
    134