[Bug c++/99513] New: ICE Segmentation fault when decltype lambda in concept template list

[Bug c++/99513] New: ICE Segmentation fault when decltype lambda in concept template list

[hewillk at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99513

            Bug ID: 99513
           Summary: ICE Segmentation fault when decltype lambda in concept
                    template list
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hewillk at gmail dot com
  Target Milestone: ---

This may be related/duplicated to the 99505, but I am not sure.

The following invalid code will trigger Segmentation fault on gcc-10 and
gcc-11:

template <decltype([]{})> concept C = true;
auto f() requires C<{}>;

(wandbox: https://wandbox.org/permlink/1gwi5zWcrICysV5G)
(godbolt: https://godbolt.org/z/PMYz6e)

[Bug c++/99513] ICE Segmentation fault when decltype lambda in concept template list since r10-3735-gcb57504a55015891

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99513

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
                 CC|                            |jason at gcc dot gnu.org,
                   |                            |marxin at gcc dot gnu.org
            Summary|ICE Segmentation fault when |ICE Segmentation fault when
                   |decltype lambda in concept  |decltype lambda in concept
                   |template list               |template list since
                   |                            |r10-3735-gcb57504a55015891
   Last reconfirmed|                            |2021-03-10

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
This one started with r10-3735-gcb57504a55015891.

[Bug c++/99513] ICE Segmentation fault when decltype lambda in concept template list since r10-3735-gcb57504a55015891

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99513

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The ICE was fixed in GCC 11+.

But we still reject:
```
template <decltype([]{})> concept C = true;

template<typename>
auto f() requires C<[]{}>;
```

[Bug c++/99513] ICE Segmentation fault when decltype lambda in concept template list since r10-3735-gcb57504a55015891

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99513

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
   Target Milestone|---                         |11.0
             Status|NEW                         |RESOLVED

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #2)
> The ICE was fixed in GCC 11+.
> 
> But we still reject:
> ```
> template <decltype([]{})> concept C = true;
> 
> template<typename>
> auto f() requires C<[]{}>;
> ```

Except that is basically PR 99516.

So closing as fixed.