clang/test/CXX/class/class.dtor/p4.cpp

   1 // RUN: %clang_cc1 -std=c++20 -verify %s
   2
   3 template <int N>
   4 struct A {
   5   ~A() = delete;                  // expected-note {{explicitly marked deleted}}
   6   ~A() requires(N == 1) = delete; // expected-note {{explicitly marked deleted}}
   7 };
   8
   9 // FIXME: We should probably make it illegal to mix virtual and non-virtual methods
  10 // this way. See CWG2488 and some discussion in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105699.
  11 template <int N>
  12 struct B {
  13   ~B() requires(N == 1) = delete; // expected-note {{explicitly marked deleted}}
  14   virtual ~B() = delete;          // expected-note {{explicitly marked deleted}}
  15 };
  16
  17 template <int N>
  18 concept CO1 = N == 1;
  19
  20 template <int N>
  21 concept CO2 = N >
  22 0;
  23
  24 template <int N>
  25 struct C {
  26   ~C() = delete; // expected-note {{explicitly marked deleted}}
  27   ~C() requires(CO1<N>) = delete;
  28   ~C() requires(CO1<N> &&CO2<N>) = delete; // expected-note {{explicitly marked deleted}}
  29 };
  30
  31 template <int N>
  32 struct D {
  33   ~D() requires(N != 0) = delete; // expected-note {{explicitly marked deleted}}
  34   // expected-note@-1 {{candidate function has been explicitly deleted}}
  35   // expected-note@-2 {{candidate function not viable: constraints not satisfied}}
  36   // expected-note@-3 {{evaluated to false}}
  37   ~D() requires(N == 1) = delete;
  38   // expected-note@-1 {{candidate function has been explicitly deleted}}
  39   // expected-note@-2 {{candidate function not viable: constraints not satisfied}}
  40   // expected-note@-3 {{evaluated to false}}
  41 };
  42
  43 template <class T>
  44 concept Foo = requires(T t) {
  45   {t.foo()};
  46 };
  47
  48 template <int N>
  49 struct E {
  50   void foo();
  51   ~E();
  52   ~E() requires Foo<E> = delete; // expected-note {{explicitly marked deleted}}
  53 };
  54
  55 template struct A<1>;
  56 template struct A<2>;
  57 template struct B<1>;
  58 template struct B<2>;
  59 template struct C<1>;
  60 template struct C<2>;
  61 template struct D<0>; // expected-error {{no viable destructor found for class 'D<0>'}} expected-note {{in instantiation of template}}
  62 template struct D<1>; // expected-error {{destructor of class 'D<1>' is ambiguous}} expected-note {{in instantiation of template}}
  63 template struct D<2>;
  64 template struct E<1>;
  65
  66 int main() {
  67   A<1> a1; // expected-error {{attempt to use a deleted function}}
  68   A<2> a2; // expected-error {{attempt to use a deleted function}}
  69   B<1> b1; // expected-error {{attempt to use a deleted function}}
  70   B<2> b2; // expected-error {{attempt to use a deleted function}}
  71   C<1> c1; // expected-error {{attempt to use a deleted function}}
  72   C<2> c2; // expected-error {{attempt to use a deleted function}}
  73   D<0> d0;
  74   D<1> d1;
  75   D<2> d2; // expected-error {{attempt to use a deleted function}}
  76   E<1> e1; // expected-error {{attempt to use a deleted function}}
  77 }