From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
 id B2B4B3840C1E; Tue,  9 Feb 2021 22:46:35 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B2B4B3840C1E
From: "redbeard0531 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/99047] New: ICE on simple task coroutine example
Date: Tue, 09 Feb 2021 22:46:35 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: unknown
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: redbeard0531 at gmail dot com
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status
 bug_severity priority component assigned_to reporter target_milestone
Message-ID: <bug-99047-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-BeenThere: gcc-bugs@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc-bugs mailing list <gcc-bugs.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Tue, 09 Feb 2021 22:46:35 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99047

            Bug ID: 99047
           Summary: ICE on simple task coroutine example
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redbeard0531 at gmail dot com
  Target Milestone: ---

https://godbolt.org/z/ecxEbb Code compiles on MSVC and clang, and at least =
on
clang produces the expected output.

#include <optional>
#include <coroutine>

template <typename T>
struct [[nodiscard]] task {
    struct promise_type  {
        std::suspend_always initial_suspend() {
            return {};
        }
        auto final_suspend() noexcept {
            struct awaiter {
                std::false_type await_ready() noexcept {
                    return {};
                }
                std::coroutine_handle<> await_suspend(std::coroutine_handle=
<>)
noexcept {
                    return next;
                }
                void await_resume() noexcept {
                }
                std::coroutine_handle<> next;
            };
            return awaiter{next};
        }

        void unhandled_exception() noexcept {
            std::terminate();
        }
        auto get_return_object() {
            return task(this);
        }
        auto coro() {
            return std::coroutine_handle<promise_type>::from_promise(*this);
        }
        void return_value(T val) {
            result.emplace(std::move(val));
        }

        std::coroutine_handle<> next;
        std::optional<T> result;
    };

    task(task&& source) : p(std::exchange(source.p, nullptr)) {}
    explicit task(promise_type* p) : p(p) {}
    ~task() {
        if (p)
            p->coro().destroy();
    }

    bool await_ready() noexcept {
        return p->coro().done();
    }
    std::coroutine_handle<> await_suspend(std::coroutine_handle<> next)
noexcept {
        p->next =3D next;
        return p->coro();
    }
    const T& await_resume() const& noexcept {
        return *p->result;
    }

    promise_type* p;
};

task<int> five() {
    co_return 5;
}
task<int> six() {
    co_return (co_await five()) + 1;
}


int main() {
    auto task =3D six();
    task.p->next =3D std::noop_coroutine();
    task.p->coro().resume();
    return *task.p->result;
}

<source>: In function 'void _Z4fivev.actor(five()::_Z4fivev.frame*)':
<source>:92:11: internal compiler error: in fold_convert_loc, at
fold-const.c:2430
   92 | task<int> five() {
      |           ^~~~
0x1ce6f09 internal_error(char const*, ...)
        ???:0
0x6b6f43 fancy_abort(char const*, int, char const*)
        ???:0
0xc92cd4 fold_convert_loc(unsigned int, tree_node*, tree_node*)
        ???:0
0xd126ae gimple_boolify(tree_node*)
        ???:0
0xd1b720 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*=
),
int)
        ???:0
0xd1bb4a gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*=
),
int)

[snipping many more frames]=