clang/test/SemaCXX/member-enum-declarations.cpp

   1 // RUN: %clang_cc1 -std=c++11 -fsyntax-only %s -verify
   2 // RUN: %clang_cc1 -std=c++14 -fsyntax-only %s -verify
   3 // RUN: %clang_cc1 -std=c++20 -fsyntax-only %s -verify
   4
   5
   6 namespace ScopedEnumerations {
   7
   8 template <typename T>
   9 struct S1 {
  10   enum class E : T;
  11 };
  12
  13 template <typename T>
  14 enum class S1<T>::E : T {
  15   S1_X = 0x123
  16 };
  17
  18 static_assert(static_cast<int>(S1<int>::E::S1_X) == 0x123, "");
  19
  20 template <typename T>
  21 struct S2 {
  22   static constexpr T f(int) { return 0; };
  23   enum class E : T;
  24   static constexpr T f(char) { return 1; };
  25   enum class E : T { X = f(T{}) };
  26 };
  27
  28 static_assert(static_cast<int>(S2<char>::E::X) == 1, "");
  29
  30 template <typename T>
  31 struct S3 {
  32   enum class E : T;
  33   enum class E : T { X = 0x7FFFFF00 }; // expected-error {{cannot be narrowed to type 'char'}} expected-warning {{implicit conversion from 'int' to 'char'}}
  34 };
  35 template struct S3<char>; // expected-note {{in instantiation}}
  36
  37 template <typename T>
  38 struct S4 {
  39   enum class E : T;
  40   enum class E : T { S4_X = 5 };
  41 };
  42
  43 auto x4 = S4<int>::E::S4_X;
  44
  45 template <typename T>
  46 T f1() {
  47   enum class E : T { X_F1, Y_F1, Z_F1 };
  48   return X_F1;  // expected-error {{use of undeclared identifier 'X_F1'}}
  49 }
  50
  51 const int resf1 = f1<int>();
  52
  53 }
  54
  55
  56 namespace UnscopedEnumerations {
  57
  58 template <typename T>
  59 struct S1 {
  60   enum E : T;
  61 };
  62
  63 template <typename T>
  64 enum S1<T>::E : T {
  65   S1_X = 0x123
  66 };
  67
  68 static_assert(static_cast<int>(S1<int>::S1_X) == 0x123, "");
  69
  70 template <typename T>
  71 struct S2 {
  72   static constexpr T f(int) { return 0; };
  73   enum E : T;
  74   static constexpr T f(char) { return 1; };
  75   enum E : T { S2_X = f(T{}) };
  76 };
  77
  78 static_assert(static_cast<int>(S2<char>::E::S2_X) == 1, "");
  79
  80 template <typename T>
  81 struct S3 {
  82   enum E : T;
  83   enum E : T { S3_X = 0x7FFFFF00 }; // expected-error {{cannot be narrowed to type 'char'}} expected-warning {{implicit conversion from 'int' to 'char'}}
  84 };
  85 template struct S3<char>; // expected-note {{in instantiation of template class}}
  86
  87 template <typename T>
  88 struct S4 {
  89   enum E : T;
  90   enum E : T { S4_X = 5 };
  91 };
  92
  93 auto x4 = S4<int>::S4_X;
  94
  95 template <typename T>
  96 struct S5 {
  97   enum E : T;
  98   T S5_X = 5; // expected-note {{previous definition is here}}
  99   enum E : T { S5_X = 5 }; // expected-error {{redefinition of 'S5_X'}}
 100 };
 101
 102
 103 template <typename T>
 104 T f1() {
 105   enum E : T { X_F2, Y_F2, Z_F2 };
 106   return X_F2;
 107 }
 108
 109 const int resf1 = f1<int>();
 110
 111 }
 112