| // RUN: %clang_cc1 -std=c++20 -Wfatal-errors -verify %s | |
| template <typename> int a; | |
| template <typename... b> concept c = a<b...>; | |
| template <typename> concept e = c<>; | |
| // must be a fatal error to trigger the crash | |
| undefined; // expected-error {{a type specifier is required for all declarations}} | |
| template <typename d> concept g = e<d>; | |
| template <g> struct h | |
| template <g d> | |
| struct h<d>; |