1 // RUN: %clang_cc1 -std=c++2b %s -verify
2 // RUN: %clang_cc1 -std=c++20 %s -verify
3 // RUN: %clang_cc1 -std=c++17 %s -verify
4 // RUN: %clang_cc1 -std=c++14 %s -verify
5 // RUN: %clang_cc1 -std=c++11 %s -verify
6 
7 auto XL0 = [] constexpr { return true; };
8 #if __cplusplus <= 201402L
9 // expected-warning@-2 {{is a C++17 extension}}
10 #endif
11 #if __cplusplus <= 202002L
12 // expected-warning@-5 {{lambda without a parameter clause is a C++2b extension}}
13 #endif
14 auto XL1 = []() mutable //
15     mutable             // expected-error{{cannot appear multiple times}}
16     mutable {};         // expected-error{{cannot appear multiple times}}
17 
18 #if __cplusplus > 201402L
19 auto XL2 = [] () constexpr mutable constexpr { }; //expected-error{{cannot appear multiple times}}
20 auto L = []() mutable constexpr { };
21 auto L2 = []() constexpr { };
22 auto L4 = []() constexpr mutable { };
23 auto XL16 = [] () constexpr
24                   mutable
25                   constexpr   //expected-error{{cannot appear multiple times}}
26                   mutable     //expected-error{{cannot appear multiple times}}
27                   mutable     //expected-error{{cannot appear multiple times}}
28                   constexpr   //expected-error{{cannot appear multiple times}}
29                   constexpr   //expected-error{{cannot appear multiple times}}
30                   { };
31 
32 #else
33 auto L = []() mutable constexpr {return 0; }; //expected-warning{{is a C++17 extension}}
34 auto L2 = []() constexpr { return 0;};//expected-warning{{is a C++17 extension}}
35 auto L4 = []() constexpr mutable { return 0; }; //expected-warning{{is a C++17 extension}}
36 #endif
37 
38 
39