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From: "avi at scylladb dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/105373] miscompile involving lambda coroutines and an
 object bitwise copied instead of via the copy constructor
Date: Sun, 04 Dec 2022 14:28:34 +0000
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X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: 11.3.1
X-Bugzilla-Keywords: C++-coroutines, c++-lambda, wrong-code
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105373

--- Comment #17 from Avi Kivity <avi at scylladb dot com> ---
This was apparently fixed by 58a7b1e354530d8dfe7d8fb859c8b8b5a9140f1f. At
least, I no longer observe copying of __old4 in gimple. Instead, I see
addresses taken, and if I squint I can see that object properly destroyed l=
ater
on.

I can't test on my full-scale program due to
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98056.

I note that one of the duplicates is titled "When constructing object, call=
ing
function and performing co_await in same statement, temporary is erroneously
moved trivially", which is exactly what this PR is about, so it can be safe=
ly
marked as a duplicate as well.

Please consider backporting https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D=
99576,
this is a subtle code generation bug.=