[Bug c++/109867] New: -Wswicht-default reports missing default in coroutine

[Bug c++/109867] New: -Wswicht-default reports missing default in coroutine

[lukaslang.bugtracker at outlook dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109867

            Bug ID: 109867
           Summary: -Wswicht-default reports missing default in coroutine
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: lukaslang.bugtracker at outlook dot com
  Target Milestone: ---

Consider the following implementation of a simple coroutine
(https://godbolt.org/z/rcevTd5f6):

#include <coroutine>

struct task
{
    struct promise_type
    {
        std::suspend_always initial_suspend();
        std::suspend_always final_suspend() noexcept;
        void unhandled_exception();
        task get_return_object();
        void return_value(int);
    };
};

int main()
{
    auto t = []() -> task
    {
        co_return 2;
    }();
} 

Compiling this with -std=c++20 -Wswitch-default -Werror results in an error at
the end of the coroutine body:

<source>:20:5: error: switch missing default case [-Werror=switch-default]
   20 |     }();

Since I can get neither clang nor msvc to complain, I assume this is a bug, or
am I missing something? If this is indeed a bug, can I work around this without
having to disable the warning?

[Bug c++/109867] -Wswitch-default reports missing default in coroutine

[piotrwn1 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109867

Piotr Nycz <piotrwn1 at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |piotrwn1 at gmail dot com

--- Comment #1 from Piotr Nycz <piotrwn1 at gmail dot com> ---
This also happens for void coroutine (return_void()).
Quite big annoying