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From: "hewillk at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/111861] New: ranges::min/max should not use `auto
 __result = *__first;`
Date: Wed, 18 Oct 2023 08:44:15 +0000
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X-Bugzilla-Product: gcc
X-Bugzilla-Component: libstdc++
X-Bugzilla-Version: 14.0
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111861

            Bug ID: 111861
           Summary: ranges::min/max should not use `auto __result =3D
                    *__first;`
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hewillk at gmail dot com
  Target Milestone: ---

The constraints on the function signature do not guarantee that

  constructible_from<remove_cvref_t<iter_reference_t<I>>, iter_reference_t<=
I>>=20

is true. The same goes for unique_copy's input_range branch.

Contrived testcase:

https://godbolt.org/z/Kannq6Yo9=