https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112696
Bug ID: 112696
Summary: ICE When specializing auto... parameter pack with
typed pack
Product: gcc
Version: 13.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: mrcmnn at gmail dot com
Target Milestone: ---
Hi everybody!
I'm experiencing ICE when trying to specialize an `<auto...>` parameter pack in
a struct. My main use-case involves concept, but I've been able to reproduce
the problem without.
I can reproduce this in g++ 10.5/11.4/12.3/13.2.
The reproduction looks like:
```c++
template <auto...>
struct sum;
template <int s, typename...Sz, Sz...sz>
struct sum<s, sz...> {
static constexpr int value = (s + ... + sz);
};
static_assert(sum<10, 1, 2>::value == 13);
```
Consider that replacing `typename...Sz, Sz...sz` with `auto...` works:
```c++
template <auto...>
struct sum;
template <int s, auto...sz>
struct sum<s, sz...> {
static constexpr int value = (s + ... + sz);
};
static_assert(sum<10, 1, 2>::value == 13);
```
