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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/112307] Segmentation fault with -O1 -fcode-hoisting
Date: Fri, 08 Mar 2024 14:30:14 +0000	[thread overview]
Message-ID: <bug-112307-4-fu5Gt9RJYG@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-112307-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112307

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I explained this in PR 109945 comment 25

There is no guaranteed copy elision for objects with a trivial copy constructor
and trivial (or deleted) destructor. The compiler is allowed to make temporary
copies, to allow passing the object in registers (which has been what the ABI
requires for decades longer than the guaranteed copy elision rules have
existed).

If you want to have self-referential pointers in your object then you need to
ensure copies really are elided. And so it should not be trivially copyable,
because that removes the guarantee of copy elision.

  parent reply	other threads:[~2024-03-08 14:30 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-31  9:39 [Bug c++/112307] New: " raffael at casagrande dot ch
2023-10-31  9:51 ` [Bug tree-optimization/112307] " rguenth at gcc dot gnu.org
2023-10-31 10:21 ` rguenth at gcc dot gnu.org
2023-10-31 10:43 ` rguenth at gcc dot gnu.org
2024-03-05 11:34 ` rguenth at gcc dot gnu.org
2024-03-05 15:05 ` redi at gcc dot gnu.org
2024-03-05 15:37 ` rguenth at gcc dot gnu.org
2024-03-08 12:58 ` raffael at casagrande dot ch
2024-03-08 14:30 ` redi at gcc dot gnu.org [this message]
2024-03-08 14:32 ` redi at gcc dot gnu.org
2024-03-08 15:12 ` raffael at casagrande dot ch

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