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From: "fchelnokov at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/111685] Segfault while sorting on array element address
Date: Wed, 04 Oct 2023 17:46:59 +0000	[thread overview]
Message-ID: <bug-111685-4-MS54rCoQZU@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-111685-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111685

--- Comment #10 from Fedor Chelnokov <fchelnokov at gmail dot com> ---
It seems that both libc++ and MS STL implement std::sort without a temporary
object passed to cmp, because they are fine with compiling the following code
in constant expression (where unrelated pointers cannot be compared):

consteval void foo() {
  std::array<int,3> nums{1, 5, 4};
  auto cmp = [](auto& a, auto& b) { return &a < &b; };
  std::sort(nums.begin(), nums.end(), cmp);
}

Online demo: https://godbolt.org/z/jdecfP6c4

Is it right that their implementations are less optimal because of no temporary
object?

  parent reply	other threads:[~2023-10-04 17:46 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-03 18:57 [Bug c++/111685] New: " knoepfel at fnal dot gov
2023-10-03 19:06 ` [Bug libstdc++/111685] " pinskia at gcc dot gnu.org
2023-10-03 19:10 ` pinskia at gcc dot gnu.org
2023-10-03 19:14 ` knoepfel at fnal dot gov
2023-10-03 19:19 ` knoepfel at fnal dot gov
2023-10-03 21:24 ` pinskia at gcc dot gnu.org
2023-10-03 21:37 ` pinskia at gcc dot gnu.org
2023-10-04  1:35 ` xry111 at gcc dot gnu.org
2023-10-04  9:48 ` redi at gcc dot gnu.org
2023-10-04 10:06 ` redi at gcc dot gnu.org
2023-10-04 17:46 ` fchelnokov at gmail dot com [this message]
2023-10-05 19:27 ` knoepfel at fnal dot gov
2023-10-06 10:10 ` fchelnokov at gmail dot com

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