[Bug c++/94752] New: [coroutines] compiler ICE with coroutine with unnamed parameter

[Bug c++/94752] New: [coroutines] compiler ICE with coroutine with unnamed parameter

[lewissbaker.opensource at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94752

            Bug ID: 94752
           Summary: [coroutines] compiler ICE with coroutine with unnamed
                    parameter
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: lewissbaker.opensource at gmail dot com
  Target Milestone: ---

See https://godbolt.org/z/QCXqeo

Compile the following source code with GCC trunk.
Flags: -std=c++20 -fcoroutines

-----
#include <coroutine>
using namespace std;

struct task {
    struct promise_type {
        promise_type() {}
        task get_return_object() { return {}; }
        suspend_never initial_suspend() { return {}; }
        suspend_never final_suspend() { return {}; }
        void return_void() {}
        void unhandled_exception() {}
    };
};

task foo(int) {
    co_return;
}
-----

Results in an internal-compile-error - segmentation-fault.
Pointing at closing curly-brace of 'foo()'.

Seems to be related to the parameter being unnamed as naming
the parameter results in this code compiling successfully.

[Bug c++/94752] [coroutines] compiler ICE with coroutine with unnamed parameter

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94752

Iain Sandoe <iains at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2020-04-25
           Assignee|unassigned at gcc dot gnu.org      |iains at gcc dot gnu.org

--- Comment #1 from Iain Sandoe <iains at gcc dot gnu.org> ---
Created attachment 48372
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48372&action=edit
fix posted

thanks for the report

[Bug c++/94752] [coroutines] compiler ICE with coroutine with unnamed parameter

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94752

Iain Sandoe <iains at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
   Target Milestone|---                         |10.0

[Bug c++/94752] [coroutines] compiler ICE with coroutine with unnamed parameter

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94752

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Iain D Sandoe <iains@gcc.gnu.org>:

https://gcc.gnu.org/g:29f55115583a0dab6cbac749c4f0804fd88e9536

commit r10-7973-g29f55115583a0dab6cbac749c4f0804fd88e9536
Author: Iain Sandoe <iain@sandoe.co.uk>
Date:   Sun Apr 26 19:34:50 2020 +0100

    coroutines: Do not assume parms are named [PR94752].

    Parameters to user-defined coroutines might be unnamed.
    In that case, we must synthesize a name for the coroutine
    frame copy.

    gcc/cp/ChangeLog:

    2020-04-26  Iain Sandoe  <iain@sandoe.co.uk>

            PR c++/94752
            * coroutines.cc (morph_fn_to_coro): Ensure that
            unnamed function params have a usable and distinct
            frame field name.

    gcc/testsuite/ChangeLog:

    2020-04-26  Iain Sandoe  <iain@sandoe.co.uk>

            PR c++/94752
            * g++.dg/coroutines/pr94752.C: New test.

[Bug c++/94752] [coroutines] compiler ICE with coroutine with unnamed parameter

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94752

Iain Sandoe <iains at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|NEW                         |RESOLVED

--- Comment #3 from Iain Sandoe <iains at gcc dot gnu.org> ---
so fixed.