1 // RUN: %clang_cc1 -std=c++2a -verify %s
2 
3 struct Good1 {
4   bool operator==(const Good1&) const = default;
5   bool operator!=(const Good1&) const = default;
6 };
7 struct Good2 {
8   friend bool operator==(const Good2&, const Good2&) = default;
9   friend bool operator!=(const Good2&, const Good2&) = default;
10 };
11 
12 enum Bool : bool {};
13 struct Bad {
14   bool &operator==(const Bad&) const = default; // expected-error {{return type for defaulted equality comparison operator must be 'bool', not 'bool &'}}
15   const bool operator!=(const Bad&) const = default; // expected-error {{return type for defaulted equality comparison operator must be 'bool', not 'const bool'}}
16   friend Bool operator==(const Bad&, const Bad&) = default; // expected-error {{return type for defaulted equality comparison operator must be 'bool', not 'Bool'}}
17   friend int operator!=(const Bad&, const Bad&) = default; // expected-error {{return type for defaulted equality comparison operator must be 'bool', not 'int'}}
18 };
19 
20 template<typename T> struct Ugly {
21   T operator==(const Ugly&) const = default; // expected-error {{return type}}
22   T operator!=(const Ugly&) const = default; // expected-error {{return type}}
23   friend T operator==(const Ugly&, const Ugly&) = default; // expected-error {{return type}}
24   friend T operator!=(const Ugly&, const Ugly&) = default; // expected-error {{return type}}
25 };
26 template struct Ugly<bool>;
27 template struct Ugly<int>; // expected-note {{in instantiation of}}
28