[Bug c++/102707] New: template coroutine generated code failed

[Bug c++/102707] New: template coroutine generated code failed

[netcan1996 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102707

            Bug ID: 102707
           Summary: template coroutine generated code failed
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: netcan1996 at gmail dot com
  Target Milestone: ---

code: https://godbolt.org/z/f591eaTja

```cpp
#include <coroutine>
#include <utility>
#include <exception>
#include <vector>

template<typename R>
struct task {
    struct promise_type;
    using coro_handle = std::coroutine_handle<promise_type>;

    auto operator co_await() && noexcept {
        return std::suspend_always{};
    }

    struct promise_type {
        auto initial_suspend() noexcept { return std::suspend_always{}; }
        auto final_suspend() noexcept {
            return std::suspend_always {};
        }
        void unhandled_exception() { std::terminate(); }
        task get_return_object() noexcept {
            return {coro_handle::from_promise(*this)};
        }

        template<class U>
        void return_value(U &&result) noexcept {
            result_ = std::forward<U>(result);
        }

        R result_;
    };

    coro_handle handle_;
};

struct Dummy {};
template<size_t N>
task<Dummy> coro_depth_n(std::vector<int>& result) {
    result.push_back(N);
    if constexpr (N > 0) {
        co_await coro_depth_n<N - 1>(result);
        result.push_back(N * 10);
    }
    co_return Dummy{};
}

void test() {
    std::vector<int> result;
    auto t = coro_depth_n<4>(result);
}
```

compiled failed message:

<source>: In instantiation of 'task<Dummy> coro_depth_n(std::vector<int>&)
[with long unsigned int N = 4]':
<source>:49:29:   required from here
<source>:44:5: internal compiler error: in tsubst_copy, at cp/pt.c:17314
   44 |     co_return Dummy{};
      |     ^~~~~~~~~
0x1ff4db9 internal_error(char const*, ...)
        ???:0
0x7d54cd fancy_abort(char const*, int, char const*)
        ???:0
0xa44627 instantiate_decl(tree_node*, bool, bool)
        ???:0
0xa8714b instantiate_pending_templates(int)
        ???:0
0x8ec779 c_parse_final_cleanups()
        ???:0
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
ASM generation compiler returned: 1
<source>: In instantiation of 'task<Dummy> coro_depth_n(std::vector<int>&)
[with long unsigned int N = 4]':
<source>:49:29:   required from here
<source>:44:5: internal compiler error: in tsubst_copy, at cp/pt.c:17314
   44 |     co_return Dummy{};
      |     ^~~~~~~~~
0x1ff4db9 internal_error(char const*, ...)
        ???:0
0x7d54cd fancy_abort(char const*, int, char const*)
        ???:0
0xa44627 instantiate_decl(tree_node*, bool, bool)
        ???:0
0xa8714b instantiate_pending_templates(int)
        ???:0
0x8ec779 c_parse_final_cleanups()
        ???:0
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Execution build compiler returned: 1

[Bug c++/102707] template coroutine generated code failed

[netcan1996 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102707

--- Comment #1 from Net Can <netcan1996 at gmail dot com> ---
the code is compiled success in msvc