[Bug c++/105104] [coroutines] ICE during GIMPLE pass: coro-early-expand-ifns
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105104
Iain Sandoe changed:
What|Removed |Added
Last reconfirmed|2022-03-30 00:00:00 |2022-4-18
CC||iains at gcc dot gnu.org,
||jakub at gcc dot gnu.org
Status|WAITING |NEW
Keywords||ice-on-valid-code
--- Comment #6 from Iain Sandoe ---
Initial analysis - perhaps some issue with constexpr processing:
When we have a void await_return() in the final_awaiter class:
final.suspend:
frame_ptr->_Coro_resume_fn = 0B;
{
struct final_awaiter Fs [value-expr: frame_ptr->Fs_1_2];
frame_ptr->_Coro_resume_index = 4;
_15 = _ptr->_Coro_self_handle;
D.9844 = std::__n4861::coroutine_handle::operator
std::__n4861::coroutine_handle (_15);
return_object::promise_type::final_awaiter::await_suspend (D.9844);
D.9768 = .CO_YIELD (4, 1, , , frame_ptr);
retval.2 = D.9768;
switch (retval.2) , case 0: , case 1: >
:
.CO_SUSPN ();
:
goto resume.4;
:
goto destroy.4;
destroy.4:
goto coro.delete.promise;
resume.4:
return_object::promise_type::final_awaiter::await_resume ();
}
when the await_resume() function is made to return an int.
final.suspend:
frame_ptr->_Coro_resume_fn = 0B;
{
destroy.4:
goto coro.delete.promise;
resume.4:
}
So we have a dangling label at the end of that scope (which then gives rise to
the crash).
* If I remove the 'contexpr' from the await_resume() function, then it all
works as expected.
* AFAICT, the content is correct in "expand_one_await_expression()".
* Altering the coroutines code to cast the result of the await_resume() to void
makes no difference.
[Bug c++/105104] [coroutines] ICE during GIMPLE pass: coro-early-expand-ifns
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105104 --- Comment #5 from John Eivind Helset --- Created attachment 52729 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52729=edit Patch with testcase. Tried adding a testcase to the g++.dg/coroutines testsuite. Used dg-ice, but it seems to complain about excess errors anyways: FAIL: g++.dg/coroutines/pr105104.C (test for excess errors) Excess errors: during GIMPLE pass: coro-early-expand-ifns
[Bug c++/105104] [coroutines] ICE during GIMPLE pass: coro-early-expand-ifns
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105104 --- Comment #4 from John Eivind Helset --- It seems a non-void return-type from await-resume of a final awaitable, combined with at least -O1 causes a segfault: https://godbolt.org/z/rzq8dM7Pr Not sure if it's the same as the one I initially encountered yet.
[Bug c++/105104] [coroutines] ICE during GIMPLE pass: coro-early-expand-ifns
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105104 Richard Biener changed: What|Removed |Added Last reconfirmed||2022-03-30 Ever confirmed|0 |1 Status|UNCONFIRMED |WAITING --- Comment #3 from Richard Biener --- Please provide preprocessed source of a testcase.
[Bug c++/105104] [coroutines] ICE during GIMPLE pass: coro-early-expand-ifns
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105104 --- Comment #2 from John Eivind Helset --- I'll try to create an MRE eventually...
[Bug c++/105104] [coroutines] ICE during GIMPLE pass: coro-early-expand-ifns
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105104 --- Comment #1 from John Eivind Helset --- Indices of `bb` and `case_bb` in `convert_single_case_switch` are: (gdb) p bb->index $18 = 154 (gdb) p case_bb->index $19 = 157 If that helps.
