// RUN: %clang_cc1 -std=c++20 -include %s %s -o %t
// RUN: %clang_cc1 -std=c++20 -emit-pch %s -o %t
// RUN: %clang_cc1 -std=c++20 -include-pch %t -verify %s
// expected-no-diagnostics
#ifndef HEADER
#define HEADER
template<typename T> auto f() -> decltype([]{ return T(42); });
#else /*included pch*/
static_assert(decltype(f<int>())()() == 42);
#endif // HEADER