clang/test/Parser/cxx2b-lambdas.cpp

   1 // RUN: %clang_cc1 -std=c++03 %s -verify                -Wno-c++23-extensions -Wno-c++20-extensions -Wno-c++17-extensions -Wno-c++14-extensions -Wno-c++11-extensions
   2 // RUN: %clang_cc1 -std=c++11 %s -verify=expected,cxx11 -Wno-c++23-extensions -Wno-c++20-extensions -Wno-c++17-extensions -Wno-c++14-extensions
   3 // RUN: %clang_cc1 -std=c++14 %s -verify                -Wno-c++23-extensions -Wno-c++20-extensions -Wno-c++17-extensions
   4 // RUN: %clang_cc1 -std=c++17 %s -verify                -Wno-c++23-extensions -Wno-c++20-extensions
   5 // RUN: %clang_cc1 -std=c++20 %s -verify                -Wno-c++23-extensions
   6 // RUN: %clang_cc1 -std=c++23 %s -verify
   7
   8 auto LL0 = [] {};
   9 auto LL1 = []() {};
  10 auto LL2 = []() mutable {};
  11 #if __cplusplus >= 201103L
  12 auto LL3 = []() constexpr {}; // cxx11-error {{return type 'void' is not a literal type}}
  13 #endif
  14
  15 #if __cplusplus >= 201103L
  16 auto L0 = [] constexpr {}; // cxx11-error {{return type 'void' is not a literal type}}
  17 #endif
  18 auto L1 = [] mutable {};
  19 #if __cplusplus >= 201103L
  20 auto L2 = [] noexcept {};
  21 auto L3 = [] constexpr mutable {}; // cxx11-error {{return type 'void' is not a literal type}}
  22 auto L4 = [] mutable constexpr {}; // cxx11-error {{return type 'void' is not a literal type}}
  23 auto L5 = [] constexpr mutable noexcept {}; // cxx11-error {{return type 'void' is not a literal type}}
  24 #endif
  25 auto L6 = [s = 1] mutable {};
  26 #if __cplusplus >= 201103L
  27 auto L7 = [s = 1] constexpr mutable noexcept {}; // cxx11-error {{return type 'void' is not a literal type}}
  28 #endif
  29 auto L8 = [] -> bool { return true; };
  30 auto L9 = []<typename T> { return true; };
  31 #if __cplusplus >= 201103L
  32 auto L10 = []<typename T> noexcept { return true; };
  33 #endif
  34 auto L11 = []<typename T> -> bool { return true; };
  35 #if __cplusplus >= 202002L
  36 auto L12 = [] consteval {};
  37 auto L13 = []() requires true {}; // expected-error{{non-templated function cannot have a requires clause}}
  38 auto L14 = []<auto> requires true() requires true {};
  39 auto L15 = []<auto> requires true noexcept {};
  40 #endif
  41 auto L16 = [] [[maybe_unused]]{};
  42
  43 #if __cplusplus >= 201103L
  44 auto XL0 = [] mutable constexpr mutable {};    // expected-error{{cannot appear multiple times}} cxx11-error {{return type 'void' is not a literal type}}
  45 auto XL1 = [] constexpr mutable constexpr {};  // expected-error{{cannot appear multiple times}} cxx11-error {{return type 'void' is not a literal type}}
  46 auto XL2 = []) constexpr mutable constexpr {}; // expected-error{{expected body of lambda expression}}
  47 auto XL3 = []( constexpr mutable constexpr {}; // expected-error{{invalid storage class specifier}} \
  48                                                // expected-error{{function parameter cannot be constexpr}} \
  49                                                // expected-error{{a type specifier is required}} \
  50                                                // expected-error{{expected ')'}} \
  51                                                // expected-note{{to match this '('}} \
  52                                                // expected-error{{expected body}} \
  53                                                // expected-warning{{duplicate 'constexpr'}}
  54 #endif
  55
  56 // http://llvm.org/PR49736
  57 auto XL4 = [] requires true {}; // expected-error{{expected body}}
  58 #if __cplusplus >= 201703L
  59 auto XL5 = []<auto> requires true requires true {}; // expected-error{{expected body}}
  60 auto XL6 = []<auto> requires true noexcept requires true {}; // expected-error{{expected body}}
  61 #endif
  62
  63 auto XL7 = []() static static {}; // expected-error {{cannot appear multiple times}}
  64 auto XL8 = []() static mutable {}; // expected-error {{cannot be both mutable and static}}
  65 #if __cplusplus >= 202002L
  66 auto XL9 = []() static consteval {};
  67 #endif
  68 #if __cplusplus >= 201103L
  69 auto XL10 = []() static constexpr {}; // cxx11-error {{return type 'void' is not a literal type}}
  70 #endif
  71
  72 auto XL11 = [] static {};
  73 auto XL12 = []() static {};
  74 auto XL13 = []() static extern {};  // expected-error {{expected body of lambda expression}}
  75 auto XL14 = []() extern {};  // expected-error {{expected body of lambda expression}}
  76
  77
  78 void static_captures() {
  79   int x;
  80   auto SC1 = [&]() static {}; // expected-error {{a static lambda cannot have any captures}}
  81   auto SC4 = [x]() static {}; // expected-error {{a static lambda cannot have any captures}}
  82   auto SC2 = [&x]() static {}; // expected-error {{a static lambda cannot have any captures}}
  83   auto SC3 = [y=x]() static {}; // expected-error {{a static lambda cannot have any captures}}
  84   auto SC5 = [&y = x]() static {}; // expected-error {{a static lambda cannot have any captures}}
  85   auto SC6 = [=]() static {}; // expected-error {{a static lambda cannot have any captures}}
  86   struct X {
  87     int z;
  88     void f() {
  89       [this]() static {}(); // expected-error {{a static lambda cannot have any captures}}
  90       [*this]() static {}(); // expected-error {{a static lambda cannot have any captures}}
  91     }
  92   };
  93 }
  94
  95 #if __cplusplus >= 201703L
  96 constexpr auto static_capture_constexpr() {
  97   char n = 'n';
  98   return [n] static { return n; }(); // expected-error {{a static lambda cannot have any captures}}
  99 }
 100 static_assert(static_capture_constexpr()); // expected-error {{static assertion expression is not an integral constant expression}}
 101
 102 constexpr auto capture_constexpr() {
 103   char n = 'n';
 104   return [n] { return n; }();
 105 }
 106 static_assert(capture_constexpr());
 107 #endif