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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
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Date: Wed, 04 Oct 2023 17:46:59 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111685

--- 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 co=
de
in constant expression (where unrelated pointers cannot be compared):

consteval void foo() {
  std::array<int,3> nums{1, 5, 4};
  auto cmp =3D [](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 tempo=
rary
object?=