clang/test/SemaCXX/pr64462.cpp

   1 // RUN: %clang_cc1 -verify -std=c++20 -fsyntax-only %s
   2
   3 auto c1(auto f, auto ...fs) {
   4   constexpr bool a = true;
   5   return [](auto) requires a {
   6     constexpr bool b = true;
   7     return []() requires a && b {
   8       constexpr bool c = true;
   9       return [](auto) requires a && b && c {
  10         constexpr bool d = true;
  11         // expected-note@+2{{because substituted constraint expression is ill-formed: no matching function for call to 'c1'}}
  12         // expected-note@+1{{candidate function not viable: constraints not satisfied}}
  13         return []() requires a && b && c && d && (c1(fs...)) {};
  14       };
  15     }();
  16   }(1);
  17 }
  18
  19 void foo() {
  20   c1(true)(1.0)(); // expected-error{{no matching function for call to object of type}}
  21 }