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From: "barry.revzin at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/95567] New: Defaulted virtual <=> has the wrong behavior
Date: Sun, 07 Jun 2020 23:34:02 +0000	[thread overview]
Message-ID: <bug-95567-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95567

            Bug ID: 95567
           Summary: Defaulted virtual <=> has the wrong behavior
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: barry.revzin at gmail dot com
  Target Milestone: ---

Reduced from Twitter user @feder_and_ink:

#include <compare>

struct B {
  B(int i) : i(i) {}

  VIRTUAL std::strong_ordering operator<=>(B const& other) const = default;
  int i;
};

struct D : B {
  D(int i, int j) : B(i), j(j) {}
  int j;
};

bool check() {
    return B(2) == D(2, 3);
}

With -DVIRTUAL=, check() returns true.
With -DVIRTUAL=virtual, check() erroneously returns false.
On compiler explorer: https://godbolt.org/z/hc3U5f

             reply	other threads:[~2020-06-07 23:34 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-07 23:34 barry.revzin at gmail dot com [this message]
2020-06-09 14:52 ` [Bug c++/95567] " barry.revzin at gmail dot com
2020-10-28 12:53 ` redi at gcc dot gnu.org
2021-08-10 16:43 ` [Bug c++/95567] Defaulted virtual <=> has the wrong behavior, vtable is checked when it should not be pinskia at gcc dot gnu.org
2021-09-29 14:33 ` ppalka at gcc dot gnu.org
2021-09-30 21:51 ` cvs-commit at gcc dot gnu.org
2021-10-06 14:15 ` cvs-commit at gcc dot gnu.org
2021-10-06 14:19 ` ppalka at gcc dot gnu.org

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