// C++ 26 P2552R3 - On the ignorability of standard attributes // { dg-do compile { target c++11 } } int arr[2]; struct S { int a, b; }; S arr2[2]; void foo (int n) { [[assume (n > 0)]]; [[assume]]; // { dg-error "wrong number of arguments specified for 'assume' attribute" } [[assume ("abc")]]; [[assume (1, 2, 3)]]; // { dg-error "wrong number of arguments specified for 'assume' attribute" } [[assume (true)]] int x1; // { dg-error "'assume' attribute ignored" } auto a = [] [[assume (true)]] () {}; // { dg-error "'assume' attribute ignored" } auto b = [] constexpr [[assume (true)]] {}; // { dg-error "'assume' attribute ignored" } // { dg-error "parameter declaration before lambda declaration specifiers only optional with" "" { target c++20_down } .-1 } // { dg-error "'constexpr' lambda only available with" "" { target c++14_down } .-2 } auto c = [] noexcept [[assume (true)]] {}; // { dg-error "'assume' attribute ignored" } // { dg-error "parameter declaration before lambda exception specification only optional with" "" { target c++20_down } .-1 } auto d = [] () [[assume (true)]] {}; // { dg-error "'assume' attribute ignored" } auto e = new int [n] [[assume (true)]]; // { dg-warning "attributes ignored on outermost array type in new expression" } auto e2 = new int [n] [[assume (true)]] [42]; // { dg-warning "attributes ignored on outermost array type in new expression" } auto f = new int [n][42] [[assume (true)]]; // { dg-error "'assume' attribute ignored" } [[assume (true)]]; [[assume (true)]] {} // { dg-warning "attributes at the beginning of statement are ignored" } [[assume (true)]] if (true) {} // { dg-warning "attributes at the beginning of statement are ignored" } [[assume (true)]] while (false) {} // { dg-warning "attributes at the beginning of statement are ignored" } [[assume (true)]] goto lab; // { dg-warning "attributes at the beginning of statement are ignored" } [[assume (true)]] lab:; // { dg-error "'assume' attribute ignored" } [[assume (true)]] try {} catch (int) {} // { dg-warning "attributes at the beginning of statement are ignored" } if ([[assume (true)]] int x = 0) {} // { dg-error "'assume' attribute ignored" } switch (n) { [[assume (true)]] case 1: // { dg-error "'assume' attribute ignored" } [[assume (true)]] break; // { dg-warning "attributes at the beginning of statement are ignored" } [[assume (true)]] default: // { dg-error "'assume' attribute ignored" } break; } for ([[assume (true)]] auto a : arr) {} // { dg-error "'assume' attribute ignored" } for ([[assume (true)]] auto [a, b] : arr2) {} // { dg-error "'assume' attribute ignored" } // { dg-error "structured bindings only available with" "" { target c++14_down } .-1 } [[assume (true)]] asm (""); // { dg-warning "attributes ignored on 'asm' declaration" } try {} catch ([[assume (true)]] int x) {} // { dg-error "'assume' attribute ignored" } try {} catch ([[assume (true)]] int) {} // { dg-error "'assume' attribute ignored" } try {} catch (int [[assume (true)]] x) {} // { dg-warning "attribute ignored" } try {} catch (int [[assume (true)]]) {} // { dg-warning "attribute ignored" } try {} catch (int x [[assume (true)]]) {} // { dg-error "'assume' attribute ignored" } } [[assume (true)]] int bar (); // { dg-error "'assume' attribute ignored" } using foobar [[assume (true)]] = int; // { dg-error "'assume' attribute ignored" } [[assume (true)]] int a; // { dg-error "'assume' attribute ignored" } [[assume (true)]] auto [b, c] = arr; // { dg-error "'assume' attribute ignored" } // { dg-error "structured bindings only available with" "" { target c++14_down } .-1 } [[assume (true)]]; // { dg-warning "attribute ignored" } inline [[assume (true)]] void baz () {} // { dg-warning "attribute ignored" } // { dg-error "standard attributes in middle of decl-specifiers" "" { target *-*-* } .-1 } constexpr [[assume (true)]] int qux () { return 0; } // { dg-warning "attribute ignored" } // { dg-error "standard attributes in middle of decl-specifiers" "" { target *-*-* } .-1 } int [[assume (true)]] d; // { dg-warning "attribute ignored" } int const [[assume (true)]] e = 1; // { dg-warning "attribute ignored" } struct A {} [[assume (true)]]; // { dg-warning "attribute ignored in declaration of 'struct A'" } struct A [[assume (true)]]; // { dg-warning "attribute ignored" } struct A [[assume (true)]] a1; // { dg-warning "attribute ignored" } A [[assume (true)]] a2; // { dg-warning "attribute ignored" } enum B { B0 } [[assume (true)]]; // { dg-warning "attribute ignored in declaration of 'enum B'" } enum B [[assume (true)]]; // { dg-warning "attribute ignored" } enum B [[assume (true)]] b1; // { dg-warning "attribute ignored" } B [[assume (true)]] b2; // { dg-warning "attribute ignored" } struct [[assume (true)]] C {}; // { dg-error "'assume' attribute ignored" } int f [[assume (true)]]; // { dg-error "'assume' attribute ignored" } int g[2] [[assume (true)]]; // { dg-error "'assume' attribute ignored" } int g2 [[assume (true)]] [2]; // { dg-error "'assume' attribute ignored" } int corge () [[assume (true)]]; // { dg-error "'assume' attribute ignored" } int *[[assume (true)]] h; // { dg-error "'assume' attribute ignored" } int & [[assume (true)]] i = f; // { dg-error "'assume' attribute ignored" } int && [[assume (true)]] j = 0; // { dg-error "'assume' attribute ignored" } int S::* [[assume (true)]] k; // { dg-error "'assume' attribute ignored" } auto l = sizeof (int [2] [[assume (true)]]); // { dg-error "'assume' attribute ignored" } int freddy ([[assume (true)]] int a, // { dg-error "'assume' attribute ignored" } [[assume (true)]] int, // { dg-error "'assume' attribute ignored" } [[assume (true)]] int c = 0, // { dg-error "'assume' attribute ignored" } [[assume (true)]] int = 0); // { dg-error "'assume' attribute ignored" } void corge ([[assume (true)]] int a, // { dg-error "'assume' attribute ignored" } [[assume (true)]] int, // { dg-error "'assume' attribute ignored" } [[assume (true)]] int c = 0, // { dg-error "'assume' attribute ignored" } [[assume (true)]] int = 0) // { dg-error "'assume' attribute ignored" } { } [[assume (true)]] void garply () // { dg-error "'assume' attribute ignored" } { } int grault (int [[assume (true)]] a, // { dg-warning "attribute ignored" } int [[assume (true)]], // { dg-warning "attribute ignored" } int [[assume (true)]] c = 0, // { dg-warning "attribute ignored" } int [[assume (true)]] = 0); // { dg-warning "attribute ignored" } void waldo (int [[assume (true)]] a, // { dg-warning "attribute ignored" } int [[assume (true)]], // { dg-warning "attribute ignored" } int [[assume (true)]] c = 0, // { dg-warning "attribute ignored" } int [[assume (true)]] = 0) // { dg-warning "attribute ignored" } { } int plugh (int a [[assume (true)]], // { dg-error "'assume' attribute ignored" } int b [[assume (true)]] = 0); // { dg-error "'assume' attribute ignored" } void thud (int a [[assume (true)]], // { dg-error "'assume' attribute ignored" } int b [[assume (true)]] = 0) // { dg-error "'assume' attribute ignored" } { } enum [[assume (true)]] D { D0 }; // { dg-error "'assume' attribute ignored" } enum class [[assume (true)]] E { E0 }; // { dg-error "'assume' attribute ignored" } enum F {}; enum [[assume (true)]] F; // { dg-warning "type attributes ignored after type is already defined" } enum G { G0 [[assume (true)]], // { dg-error "'assume' attribute ignored" } G1 [[assume (true)]] = 2 // { dg-error "'assume' attribute ignored" } }; namespace [[assume (true)]] H { using H0 = int; } // { dg-warning "'assume' attribute directive ignored" } */ namespace [[assume (true)]] {} // { dg-warning "'assume' attribute directive ignored" } [[assume (true)]] using namespace H; // { dg-warning "'assume' attribute directive ignored" } struct [[assume (true)]] I // { dg-error "'assume' attribute ignored" } { [[assume (true)]]; // { dg-error "declaration does not declare anything" } [[assume (true)]] int i; // { dg-error "'assume' attribute ignored" } [[assume (true)]] int foo (); // { dg-error "'assume' attribute ignored" } [[assume (true)]] int bar () { return 1; } // { dg-error "'assume' attribute ignored" } [[assume (true)]] int : 0; // { dg-error "'assume' attribute ignored" } [[assume (true)]] int i2 : 5; // { dg-error "'assume' attribute ignored" } [[assume (true)]] static int i3; // { dg-error "'assume' attribute ignored" } static int i4; }; [[assume (true)]] int I::i4 = 0; // { dg-error "'assume' attribute ignored" } struct J : [[assume (true)]] C {}; // { dg-warning "attributes on base specifiers are ignored" } #if __cpp_concepts >= 201907L template concept K [[assume (true)]] = requires { true; }; // { dg-error "'assume' attribute ignored" "" { target c++20 } } #endif typedef int L [[assume (true)]]; // { dg-error "'assume' attribute ignored" } template struct M {}; template <> struct [[assume (true)]] M { int m; }; // { dg-error "'assume' attribute ignored" } typedef int N[2] [[assume (true)]]; // { dg-error "'assume' attribute ignored" } typedef int O [[assume (true)]] [2]; // { dg-error "'assume' attribute ignored" }