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