1 // RUN: %clang_cc1 -fsyntax-only -verify %s 2 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++98 %s 3 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s 4 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++2a %s 5 6 struct S { 7 S(); 8 #if __cplusplus <= 199711L 9 // expected-note@-2 {{because type 'S' has a user-provided default constructor}} 10 #endif 11 }; 12 13 struct { // expected-error {{anonymous structs and classes must be class members}} expected-warning {{does not declare anything}} 14 }; 15 16 struct E { 17 struct { 18 S x; 19 #if __cplusplus <= 199711L 20 // expected-error@-2 {{anonymous struct member 'x' has a non-trivial default constructor}} 21 #endif 22 }; 23 static struct { // expected-warning {{does not declare anything}} 24 }; 25 class { 26 int anon_priv_field; // expected-error {{anonymous struct cannot contain a private data member}} 27 }; 28 }; 29 30 template <class T> void foo(T); 31 typedef struct { // expected-error {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration after its linkage was computed; add a tag name here to establish linkage prior to definition}} 32 #if __cplusplus <= 199711L 33 // expected-note@-2 {{declared here}} 34 #endif 35 36 void test() { // expected-note {{type is not C-compatible due to this member declaration}} 37 foo(this); 38 #if __cplusplus <= 199711L 39 // expected-warning@-2 {{template argument uses unnamed type}} 40 #endif 41 } 42 } A; // expected-note {{type is given name 'A' for linkage purposes by this typedef declaration}} 43 44 typedef struct { // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 45 int x = 0; // expected-note {{type is not C-compatible due to this default member initializer}} expected-warning 0-1{{extension}} 46 } B; // expected-note {{type is given name 'B' for linkage purposes by this typedef declaration}} 47 48 typedef struct // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 49 : B { // expected-note {{type is not C-compatible due to this base class}} 50 } C; // expected-note {{type is given name 'C' for linkage purposes by this typedef declaration}} 51 52 #if __cplusplus > 201703L 53 typedef struct { // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 54 static_assert([]{ return true; }()); // expected-note {{type is not C-compatible due to this lambda expression}} 55 } Lambda1; // expected-note {{type is given name 'Lambda1' for linkage purposes by this typedef declaration}} 56 57 template<int> struct X {}; 58 typedef struct { // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 59 X<[]{ return 0; }()> x; // expected-note {{type is not C-compatible due to this lambda expression}} 60 // FIXME: expected-error@-1 {{lambda expression cannot appear}} 61 } Lambda2; // expected-note {{type is given name 'Lambda2' for linkage purposes by this typedef declaration}} 62 63 typedef struct { // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 64 enum E { 65 a = []{ return 1; }() // expected-note {{type is not C-compatible due to this lambda expression}} 66 }; 67 } Lambda3; // expected-note {{type is given name 'Lambda3' for linkage purposes by this typedef declaration}} 68 #endif 69 70 typedef struct { // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 71 template<int> void f() {} // expected-note {{type is not C-compatible due to this member declaration}} 72 } Template; // expected-note {{type is given name 'Template' for linkage purposes by this typedef declaration}} 73 74 typedef struct { // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 75 struct U { 76 void f(); // expected-note {{type is not C-compatible due to this member declaration}} 77 }; 78 } Nested; // expected-note {{type is given name 'Nested' for linkage purposes by this typedef declaration}} 79 80 typedef struct { // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 81 friend void f() {} // expected-note {{type is not C-compatible due to this friend declaration}} 82 } Friend; // expected-note {{type is given name 'Friend' for linkage purposes by this typedef declaration}} 83 84 typedef struct { // expected-warning {{anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here}} 85 template<typename T> friend void f() {} // expected-note {{type is not C-compatible due to this friend declaration}} 86 } FriendTemplate; // expected-note {{type is given name 'FriendTemplate' for linkage purposes by this typedef declaration}} 87 88 // Check that we don't diagnose the permitted cases: 89 typedef struct { 90 // (non-members) 91 _Static_assert(true, ""); 92 int : 0; 93 /*empty-declaration*/; 94 95 // non-static data members 96 int a; 97 // member enumerations 98 enum E { x, y, z }; 99 // member classes 100 struct S {}; 101 102 // recursively 103 struct T { int a; }; 104 } OK; 105 106 // There are still some known permitted cases that require an early linkage 107 // computation. Ensure we diagnose those too. 108 namespace ValidButUnsupported { 109 #if __cplusplus >= 201402L 110 template<typename T> auto compute_linkage() { 111 static int n; 112 return &n; 113 } 114 115 typedef struct { // expected-error {{unsupported: anonymous type given name for linkage purposes by typedef declaration after its linkage was computed; add a tag name here to establish linkage}} 116 struct X {}; 117 decltype(compute_linkage<X>()) a; 118 } A; // expected-note {{by this typedef declaration}} 119 #endif 120 121 // This fails in some language modes but not others. 122 template<typename T> struct Y { 123 static const int value = 10; 124 }; 125 typedef struct { // expected-error 0-1{{unsupported}} 126 enum X {}; 127 int arr[Y<X>::value]; 128 } B; // expected-note 0-1{{by this typedef}} 129 130 template<typename T> void f() {} 131 typedef struct { // expected-error {{unsupported}} 132 enum X {}; 133 int arr[&f<X> ? 1 : 2]; 134 } C; // expected-note {{by this typedef}} 135 } 136 137 namespace ImplicitDecls { 138 struct Destructor { 139 ~Destructor() {} 140 }; 141 typedef struct { 142 } Empty; 143 144 typedef struct { 145 Destructor x; 146 } A; 147 148 typedef struct { 149 Empty E; 150 } B; 151 152 typedef struct { 153 const Empty E; 154 } C; 155 } // namespace ImplicitDecls 156 157 struct { 158 static int x; // expected-error {{static data member 'x' not allowed in anonymous struct}} 159 } static_member_1; 160 161 class { 162 struct A { 163 static int x; // expected-error {{static data member 'x' not allowed in anonymous class}} 164 } x; 165 } static_member_2; 166 167 union { 168 struct A { 169 struct B { 170 static int x; // expected-error {{static data member 'x' not allowed in anonymous union}} 171 } x; 172 } x; 173 } static_member_3; 174