clang/test/Parser/cxx0x-lambda-expressions.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify=expected,cxx14ext,cxx17ext,cxx20ext,cxx23ext -std=c++03 -Wno-c99-designator %s -Wno-c++11-extensions
   2 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify=expected,cxx14ext,cxx17ext,cxx20ext,cxx23ext -std=c++11 -Wno-c99-designator %s
   3 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify=expected,cxx17ext,cxx20ext,cxx23ext          -std=c++14 -Wno-c99-designator %s
   4 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify=expected,cxx20ext,cxx23ext                   -std=c++17 -Wno-c99-designator %s
   5 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify=expected,cxx23ext                            -std=c++20 -Wno-c99-designator %s
   6 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify=expected                                     -std=c++23 -Wno-c99-designator %s
   7
   8 enum E { e };
   9
  10 #if __cplusplus >= 201103L
  11 constexpr int id(int n) { return n; }
  12 #endif
  13
  14 class C {
  15
  16   int f() {
  17     int foo, bar;
  18
  19     []; // expected-error {{expected body of lambda expression}}
  20     [+] {}; // expected-error {{expected variable name or 'this' in lambda capture list}}
  21     [foo+] {}; // expected-error {{expected ',' or ']' in lambda capture list}}
  22     [foo,&this] {}; // expected-error {{'this' cannot be captured by reference}}
  23     [&this] {}; // expected-error {{'this' cannot be captured by reference}}
  24     [&,] {}; // expected-error {{expected variable name or 'this' in lambda capture list}}
  25     [=,] {}; // expected-error {{expected variable name or 'this' in lambda capture list}}
  26     [] {};
  27     [=] (int i) {};
  28     [&] (int) mutable -> void {};
  29     [foo,bar] () { return 3; };
  30     [=,&foo] () {};
  31     [&,foo] () {};
  32     [this] () {};
  33     [] () -> class C { return C(); };
  34     [] () -> enum E { return e; };
  35
  36     [] -> int { return 0; }; // cxx23ext-warning {{lambda without a parameter clause is a C++23 extension}}
  37     [] mutable -> int { return 0; }; // cxx23ext-warning {{is a C++23 extension}}
  38
  39     [](int) -> {}; // PR13652 expected-error {{expected a type}}
  40     return 1;
  41   }
  42
  43   void designator_or_lambda() {
  44     typedef int T;
  45     const int b = 0;
  46     const int c = 1;
  47     int d;
  48     int a1[1] = {[b] (T()) {}}; // expected-error{{no viable conversion from '(lambda}}
  49     int a2[1] = {[b] = 1 };
  50     int a3[1] = {[b,c] = 1 }; // expected-error{{expected ']'}} expected-note {{to match}}
  51     int a4[1] = {[&b] = 1 }; // expected-error{{integral constant expression must have integral or unscoped enumeration type, not 'const int *'}}
  52     int a5[3] = { []{return 0;}() };
  53     int a6[1] = {[this] = 1 }; // expected-error{{integral constant expression must have integral or unscoped enumeration type, not 'C *'}}
  54     int a7[1] = {[d(0)] { return d; } ()}; // cxx14ext-warning {{initialized lambda captures are a C++14 extension}}
  55     int a8[1] = {[d = 0] { return d; } ()}; // cxx14ext-warning {{initialized lambda captures are a C++14 extension}}
  56 #if __cplusplus >= 201103L
  57     int a10[1] = {[id(0)] { return id; } ()}; // cxx14ext-warning {{initialized lambda captures are a C++14 extension}}
  58 #endif
  59     int a9[1] = {[d = 0] = 1}; // expected-error{{is not an integral constant expression}}
  60 #if __cplusplus >= 201402L
  61     // expected-note@-2{{constant expression cannot modify an object that is visible outside that expression}}
  62 #endif
  63 #if __cplusplus >= 201103L
  64     int a11[1] = {[id(0)] = 1};
  65 #endif
  66   }
  67
  68   void delete_lambda(int *p) {
  69     delete [] p;
  70     delete [] (int*) { new int }; // ok, compound-literal, not lambda
  71     delete [] { return new int; } (); // expected-error {{'[]' after delete interpreted as 'delete[]'}}
  72     delete [&] { return new int; } (); // ok, lambda
  73
  74     delete []() { return new int; }(); // expected-error{{'[]' after delete interpreted as 'delete[]'}}
  75     delete [](E Enum) { return new int((int)Enum); }(e); // expected-error{{'[]' after delete interpreted as 'delete[]'}}
  76 #if __cplusplus > 201703L
  77     delete []<int = 0>() { return new int; }(); // expected-error{{'[]' after delete interpreted as 'delete[]'}}
  78 #endif
  79   }
  80
  81   // We support init-captures in C++11 as an extension.
  82   int z;
  83   void init_capture() {
  84     [n(0)] () mutable -> int { return ++n; }; // cxx14ext-warning    {{initialized lambda captures are a C++14 extension}}
  85     [n{0}] { return; };                       // cxx14ext-warning    {{initialized lambda captures are a C++14 extension}}
  86     [a([&b = z]{})](){};                      // cxx14ext-warning 2  {{initialized lambda captures are a C++14 extension}}
  87     [n = 0] { return ++n; };                  // expected-error      {{captured by copy in a non-mutable}}
  88                                               // cxx14ext-warning@-1 {{initialized lambda captures are a C++14 extension}}
  89     [n = {0}] { return; };                    // expected-error      {{<initializer_list>}}
  90                                               // cxx14ext-warning@-1 {{initialized lambda captures are a C++14 extension}}
  91
  92     int x = 4;
  93     auto y = [&r = x, x = x + 1]() -> int { // cxx14ext-warning 2 {{initialized lambda captures are a C++14 extension}}
  94       r += 2;
  95       return x + 2;
  96     } ();
  97   }
  98
  99   void attributes() {
 100     [] __attribute__((noreturn)){}; // cxx23ext-warning {{lambda without a parameter clause is a C++23 extension}}
 101
 102     []() [[]]
 103       mutable {}; // expected-error {{expected body of lambda expression}}
 104
 105     []() [[]] {};
 106     []() [[]] -> void {};
 107     []() mutable [[]] -> void {};
 108 #if __cplusplus >= 201103L
 109     []() mutable noexcept [[]] -> void {};
 110 #endif
 111
 112     // Testing GNU-style attributes on lambdas -- the attribute is specified
 113     // before the mutable specifier instead of after (unlike C++11).
 114     []() __attribute__((noreturn)) mutable { while(1); };
 115     []() mutable
 116       __attribute__((noreturn)) { while(1); }; // expected-error {{expected body of lambda expression}}
 117
 118     // Testing support for P2173 on adding attributes to the declaration
 119     // rather than the type.
 120     [][[]](){}; // cxx23ext-warning {{an attribute specifier sequence in this position is a C++23 extension}}
 121
 122     []<typename>[[]](){}; // cxx20ext-warning    {{explicit template parameter list for lambdas is a C++20 extension}}
 123                           // cxx23ext-warning@-1 {{an attribute specifier sequence in this position is a C++23 extension}}
 124
 125     [][[]]{}; // cxx23ext-warning {{an attribute specifier sequence in this position is a C++23 extension}}
 126   }
 127
 128   void missing_parens() {
 129     [] mutable {}; // cxx23ext-warning {{is a C++23 extension}}
 130 #if __cplusplus >= 201103L
 131     [] noexcept {}; // cxx23ext-warning {{is a C++23 extension}}
 132 #endif
 133   }
 134 };
 135
 136 template <typename>
 137 void PR22122() {
 138   [](int) -> {}; // expected-error {{expected a type}}
 139 }
 140
 141 template void PR22122<int>();
 142
 143 namespace PR42778 {
 144 struct A {
 145   template <class F> A(F&&) {}
 146 };
 147
 148 struct S {
 149   void mf() { A(([*this]{})); } // cxx17ext-warning {{'*this' by copy is a C++17 extension}}
 150 };
 151 }
 152
 153 struct S {
 154   template <typename T>
 155   void m (T x =[0); // expected-error{{expected variable name or 'this' in lambda capture list}}
 156 } s;
 157
 158 struct U {
 159   template <typename T>
 160   void m_fn1(T x = 0[0); // expected-error{{expected ']'}} expected-note{{to match this '['}}
 161 } *U;