https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111453
Bug ID: 111453
Summary: ICE on concept with incorrectly ordered template
parameter pack
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: stevenxia990430 at gmail dot com
Target Milestone: ---
The following invalid program reports an internal compiler error. Failed on
gcc-trunk.
To quickly reproduce: https://gcc.godbolt.org/z/PcEreesPo
```
#include <concepts>
template<typename... Ts, typename T> // incorrectly ordered template parameters
concept IsIn = (... || std::same_as<Ts, T>);
template<typename T, typename... Ts>
concept IsNotIn = !IsIn<Ts...>(T);
```
Note after changing from `template<typename... Ts, typename T>` ->
`template<typename T, typename... Ts>`, gcc no longer ICE.
