[clang] Add tests with member enum redeclarations

Author: thebrandre

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

@@ -0,0 +1,112 @@
+// RUN: %clang_cc1 -std=c++11 -fsyntax-only %s -verify
+// RUN: %clang_cc1 -std=c++14 -fsyntax-only %s -verify
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only %s -verify
+
+
+namespace ScopedEnumerations {
+
+template <typename T>
+struct S1 {
+  enum class E : T;
+};
+
+template <typename T>
+enum class S1<T>::E : T {
+  S1_X = 0x123
+};
+
+static_assert(static_cast<int>(S1<int>::E::S1_X) == 0x123, "");
+
+template <typename T>
+struct S2 {
+  static constexpr T f(int) { return 0; };
+  enum class E : T;
+  static constexpr T f(char) { return 1; };
+  enum class E : T { X = f(T{}) };
+};
+
+static_assert(static_cast<int>(S2<char>::E::X) == 1, "");
+
+template <typename T>
+struct S3 {
+  enum class E : T;
+  enum class E : T { X = 0x7FFFFF00 }; // expected-error {{cannot be narrowed to type 'char'}} expected-warning {{implicit conversion from 'int' to 'char'}}
+};
+template struct S3<char>; // expected-note {{in instantiation}}
+
+template <typename T>
+struct S4 {
+  enum class E : T;
+  enum class E : T { S4_X = 5 };
+};
+
+auto x4 = S4<int>::E::S4_X;
+
+template <typename T>
+T f1() {
+  enum class E : T { X_F1, Y_F1, Z_F1 };
+  return X_F1;  // expected-error {{use of undeclared identifier 'X_F1'}}
+}
+
+const int resf1 = f1<int>();
+
+}
+
+
+namespace UnscopedEnumerations {
+
+template <typename T>
+struct S1 {
+  enum E : T;
+};
+
+template <typename T>
+enum S1<T>::E : T {
+  S1_X = 0x123
+};
+
+static_assert(static_cast<int>(S1<int>::S1_X) == 0x123, "");
+
+template <typename T>
+struct S2 {
+  static constexpr T f(int) { return 0; };
+  enum E : T;
+  static constexpr T f(char) { return 1; };
+  enum E : T { S2_X = f(T{}) };
+};
+
+static_assert(static_cast<int>(S2<char>::E::S2_X) == 1, "");
+
+template <typename T>
+struct S3 {
+  enum E : T;
+  enum E : T { S3_X = 0x7FFFFF00 }; // expected-error {{cannot be narrowed to type 'char'}} expected-warning {{implicit conversion from 'int' to 'char'}}
+};
+template struct S3<char>; // expected-note {{in instantiation of template class}}
+
+template <typename T>
+struct S4 {
+  enum E : T;
+  enum E : T { S4_X = 5 };
+};
+
+auto x4 = S4<int>::S4_X;
+
+template <typename T>
+struct S5 {
+  enum E : T;
+  T S5_X = 5; // expected-note {{previous definition is here}}
+  enum E : T { S5_X = 5 }; // expected-error {{redefinition of 'S5_X'}}
+};
+
+
+template <typename T>
+T f1() {
+  enum E : T { X_F2, Y_F2, Z_F2 };
+  return X_F2;
+}
+
+const int resf1 = f1<int>();
+
+}
+