clang/test/CXX/module/module.interface/p6.cpp

   1 // The test is check we couldn't export a redeclaration which isn't exported previously and
   2 // check it is OK to redeclare no matter exported nor not if is the previous declaration is exported.
   3 // RUN: %clang_cc1 -std=c++20 %s -verify
   4
   5 export module X;
   6
   7 struct S { // expected-note {{previous declaration is here}}
   8   int n;
   9 };
  10 typedef S S;
  11 export typedef S S; // OK, does not redeclare an entity
  12 export struct S;    // expected-error {{cannot export redeclaration 'S' here since the previous declaration has module linkage}}
  13
  14 namespace A {
  15 struct X; // expected-note {{previous declaration is here}}
  16 export struct Y;
  17 } // namespace A
  18
  19 namespace A {
  20 export struct X; // expected-error {{cannot export redeclaration 'X' here since the previous declaration has module linkage}}
  21 export struct Y; // OK
  22 struct Z;        // expected-note {{previous declaration is here}}
  23 export struct Z; // expected-error {{cannot export redeclaration 'Z' here since the previous declaration has module linkage}}
  24 } // namespace A
  25
  26 namespace A {
  27 struct B;    // expected-note {{previous declaration is here}}
  28 struct C {}; // expected-note {{previous declaration is here}}
  29 } // namespace A
  30
  31 namespace A {
  32 export struct B {}; // expected-error {{cannot export redeclaration 'B' here since the previous declaration has module linkage}}
  33 export struct C;    // expected-error {{cannot export redeclaration 'C' here since the previous declaration has module linkage}}
  34 } // namespace A
  35
  36 template <typename T>
  37 struct TemplS; // expected-note {{previous declaration is here}}
  38
  39 export template <typename T>
  40 struct TemplS {}; // expected-error {{cannot export redeclaration 'TemplS' here since the previous declaration has module linkage}}
  41
  42 template <typename T>
  43 struct TemplS2; // expected-note {{previous declaration is here}}
  44
  45 export template <typename U>
  46 struct TemplS2 {}; // expected-error {{cannot export redeclaration 'TemplS2' here since the previous declaration has module linkage}}
  47
  48 void baz();        // expected-note {{previous declaration is here}}
  49 export void baz(); // expected-error {{cannot export redeclaration 'baz' here since the previous declaration has module linkage}}
  50
  51 namespace A {
  52 export void foo();
  53 void bar();        // expected-note {{previous declaration is here}}
  54 export void bar(); // expected-error {{cannot export redeclaration 'bar' here since the previous declaration has module linkage}}
  55 void f1();         // expected-note {{previous declaration is here}}
  56 } // namespace A
  57
  58 // OK
  59 //
  60 // [module.interface]/p6
  61 // A redeclaration of an entity X is implicitly exported if X was introduced by an exported declaration
  62 void A::foo();
  63
  64 // The compiler couldn't export A::f1() here since A::f1() is declared above without exported.
  65 // See [module.interface]/p6 for details.
  66 export void A::f1(); // expected-error {{cannot export redeclaration 'f1' here since the previous declaration has module linkage}}
  67
  68 template <typename T>
  69 void TemplFunc(); // expected-note {{previous declaration is here}}
  70
  71 export template <typename T>
  72 void TemplFunc() { // expected-error {{cannot export redeclaration 'TemplFunc' here since the previous declaration has module linkage}}
  73 }
  74
  75 namespace A {
  76 template <typename T>
  77 void TemplFunc2(); // expected-note {{previous declaration is here}}
  78 export template <typename T>
  79 void TemplFunc2() {} // expected-error {{cannot export redeclaration 'TemplFunc2' here since the previous declaration has module linkage}}
  80 template <typename T>
  81 void TemplFunc3(); // expected-note {{previous declaration is here}}
  82 } // namespace A
  83
  84 export template <typename T>
  85 void A::TemplFunc3() {} // expected-error {{cannot export redeclaration 'TemplFunc3' here since the previous declaration has module linkage}}
  86
  87 int var;        // expected-note {{previous declaration is here}}
  88 export int var; // expected-error {{cannot export redeclaration 'var' here since the previous declaration has module linkage}}
  89
  90 template <typename T>
  91 T TemplVar; // expected-note {{previous declaration is here}}
  92 export template <typename T>
  93 T TemplVar; // expected-error {{cannot export redeclaration 'TemplVar' here since the previous declaration has module linkage}}
  94
  95 // Test the compiler wouldn't complain about the redeclaration of friend in exported class.
  96 namespace Friend {
  97 template <typename T>
  98 class bar;
  99 class gua;
 100 template <typename T>
 101 void hello();
 102 void hi();
 103 export class foo;
 104 bool operator<(const foo &a, const foo &b);
 105 export class foo {
 106   template <typename T>
 107   friend class bar;
 108   friend class gua;
 109   template <typename T>
 110   friend void hello();
 111   friend void hi();
 112   friend bool operator<(const foo &a, const foo &b);
 113 };
 114 } // namespace Friend