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

   1 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify -std=c++11 -Wno-c99-designator %s
   2 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify -std=c++20 -Wno-c99-designator %s
   3 // RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify -std=c++23 -Wno-c99-designator %s
   4
   5 enum E { e };
   6
   7 constexpr int id(int n) { return n; }
   8
   9 class C {
  10
  11   int f() {
  12     int foo, bar;
  13
  14     []; // expected-error {{expected body of lambda expression}}
  15     [+] {}; // expected-error {{expected variable name or 'this' in lambda capture list}}
  16     [foo+] {}; // expected-error {{expected ',' or ']' in lambda capture list}}
  17     [foo,&this] {}; // expected-error {{'this' cannot be captured by reference}}
  18     [&this] {}; // expected-error {{'this' cannot be captured by reference}}
  19     [&,] {}; // expected-error {{expected variable name or 'this' in lambda capture list}}
  20     [=,] {}; // expected-error {{expected variable name or 'this' in lambda capture list}}
  21     [] {};
  22     [=] (int i) {};
  23     [&] (int) mutable -> void {};
  24     [foo,bar] () { return 3; };
  25     [=,&foo] () {};
  26     [&,foo] () {};
  27     [this] () {};
  28     [] () -> class C { return C(); };
  29     [] () -> enum E { return e; };
  30
  31     [] -> int { return 0; };
  32     [] mutable -> int { return 0; };
  33 #if __cplusplus <= 202002L
  34     // expected-warning@-3 {{lambda without a parameter clause is a C++23 extension}}
  35     // expected-warning@-3 {{is a C++23 extension}}
  36 #endif
  37     [](int) -> {}; // PR13652 expected-error {{expected a type}}
  38     return 1;
  39   }
  40
  41   void designator_or_lambda() {
  42     typedef int T;
  43     const int b = 0;
  44     const int c = 1;
  45     int d;
  46     int a1[1] = {[b] (T()) {}}; // expected-error{{no viable conversion from '(lambda}}
  47     int a2[1] = {[b] = 1 };
  48     int a3[1] = {[b,c] = 1 }; // expected-error{{expected ']'}} expected-note {{to match}}
  49     int a4[1] = {[&b] = 1 }; // expected-error{{integral constant expression must have integral or unscoped enumeration type, not 'const int *'}}
  50     int a5[3] = { []{return 0;}() };
  51     int a6[1] = {[this] = 1 }; // expected-error{{integral constant expression must have integral or unscoped enumeration type, not 'C *'}}
  52     int a7[1] = {[d(0)] { return d; } ()};
  53     int a8[1] = {[d = 0] { return d; } ()};
  54     int a10[1] = {[id(0)] { return id; } ()};
  55 #if __cplusplus <= 201103L
  56     // expected-warning@-4{{extension}}
  57     // expected-warning@-4{{extension}}
  58     // expected-warning@-4{{extension}}
  59 #endif
  60     int a9[1] = {[d = 0] = 1}; // expected-error{{is not an integral constant expression}}
  61 #if __cplusplus >= 201402L
  62     // expected-note@-2{{constant expression cannot modify an object that is visible outside that expression}}
  63 #endif
  64     int a11[1] = {[id(0)] = 1};
  65   }
  66
  67   void delete_lambda(int *p) {
  68     delete [] p;
  69     delete [] (int*) { new int }; // ok, compound-literal, not lambda
  70     delete [] { return new int; } (); // expected-error {{'[]' after delete interpreted as 'delete[]'}}
  71     delete [&] { return new int; } (); // ok, lambda
  72
  73     delete []() { return new int; }(); // expected-error{{'[]' after delete interpreted as 'delete[]'}}
  74     delete [](E Enum) { return new int((int)Enum); }(e); // expected-error{{'[]' after delete interpreted as 'delete[]'}}
  75 #if __cplusplus > 201703L
  76     delete []<int = 0>() { return new int; }(); // expected-error{{'[]' after delete interpreted as 'delete[]'}}
  77 #endif
  78   }
  79
  80   // We support init-captures in C++11 as an extension.
  81   int z;
  82   void init_capture() {
  83     [n(0)] () mutable -> int { return ++n; };
  84     [n{0}] { return; };
  85     [a([&b = z]{})](){};
  86     [n = 0] { return ++n; }; // expected-error {{captured by copy in a non-mutable}}
  87     [n = {0}] { return; }; // expected-error {{<initializer_list>}}
  88 #if __cplusplus <= 201103L
  89     // expected-warning@-6{{extension}}
  90     // expected-warning@-6{{extension}}
  91     // expected-warning@-6{{extension}}
  92     // expected-warning@-7{{extension}}
  93     // expected-warning@-7{{extension}}
  94     // expected-warning@-7{{extension}}
  95 #endif
  96
  97     int x = 4;
  98     auto y = [&r = x, x = x + 1]() -> int {
  99 #if __cplusplus <= 201103L
 100       // expected-warning@-2{{extension}}
 101       // expected-warning@-3{{extension}}
 102 #endif
 103       r += 2;
 104       return x + 2;
 105     } ();
 106   }
 107
 108   void attributes() {
 109     [] __attribute__((noreturn)){};
 110 #if __cplusplus <= 202002L
 111     // expected-warning@-2 {{is a C++23 extension}}
 112 #endif
 113     []() [[]]
 114       mutable {}; // expected-error {{expected body of lambda expression}}
 115
 116     []() [[]] {};
 117     []() [[]] -> void {};
 118     []() mutable [[]] -> void {};
 119     []() mutable noexcept [[]] -> void {};
 120
 121     // Testing GNU-style attributes on lambdas -- the attribute is specified
 122     // before the mutable specifier instead of after (unlike C++11).
 123     []() __attribute__((noreturn)) mutable { while(1); };
 124     []() mutable
 125       __attribute__((noreturn)) { while(1); }; // expected-error {{expected body of lambda expression}}
 126
 127     // Testing support for P2173 on adding attributes to the declaration
 128     // rather than the type.
 129     [][[]](){};
 130 #if __cplusplus <= 202002L
 131     // expected-warning@-2 {{an attribute specifier sequence in this position is a C++23 extension}}
 132 #endif
 133 #if __cplusplus > 201703L
 134     []<typename>[[]](){};
 135 #if __cplusplus <= 202002L
 136     // expected-warning@-2 {{an attribute specifier sequence in this position is a C++23 extension}}
 137 #endif
 138 #endif
 139     [][[]]{};
 140 #if __cplusplus <= 202002L
 141     // expected-warning@-2 {{an attribute specifier sequence in this position is a C++23 extension}}
 142 #endif
 143   }
 144
 145   void missing_parens() {
 146     [] mutable {};
 147     [] noexcept {};
 148 #if __cplusplus <= 202002L
 149     // expected-warning@-3 {{is a C++23 extension}}
 150     // expected-warning@-3 {{is a C++23 extension}}
 151 #endif
 152   }
 153 };
 154
 155 template <typename>
 156 void PR22122() {
 157   [](int) -> {}; // expected-error {{expected a type}}
 158 }
 159
 160 template void PR22122<int>();
 161
 162 namespace PR42778 {
 163 struct A {
 164   template <class F> A(F&&) {}
 165 };
 166
 167 struct S {
 168   void mf() { A{[*this]{}}; }
 169 #if __cplusplus < 201703L
 170   // expected-warning@-2 {{C++17 extension}}
 171 #endif
 172 };
 173 }
 174
 175 struct S {
 176   template <typename T>
 177   void m (T x =[0); // expected-error{{expected variable name or 'this' in lambda capture list}}
 178 } s;
 179
 180 struct U {
 181   template <typename T>
 182   void m_fn1(T x = 0[0); // expected-error{{expected ']'}} expected-note{{to match this '['}}
 183 } *U;