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From: "de34 at live dot cn" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/113200] std::char_traits<char>::move is not constexpr when the argument is a string literal
Date: Thu, 04 Jan 2024 01:58:50 +0000	[thread overview]
Message-ID: <bug-113200-4-IcGuroFFHS@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-113200-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113200

Jiang An <de34 at live dot cn> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |de34 at live dot cn

--- Comment #9 from Jiang An <de34 at live dot cn> ---
(In reply to Peter Dimov from comment #3)
> I think that the compiler is correct; string literal address comparisons
> aren't constant expressions. Clang gives the same error:
> https://godbolt.org/z/xPWEf4z63.

This looks weird... It seems that `+"abc" == +"def"` is never unspecified (must
be false, but Clang rejects it in constant evaluation), while `"abcd" + 1 ==
+"bcd"` is unspecified.

It's unclear to me whether we can practically detect all kinds of
unspecifiedness in pointer comparision involving string literals.

  parent reply	other threads:[~2024-01-04  1:58 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-02 15:41 [Bug libstdc++/113200] New: " pdimov at gmail dot com
2024-01-02 16:45 ` [Bug c++/113200] " pinskia at gcc dot gnu.org
2024-01-02 16:47 ` [Bug libstdc++/113200] " pinskia at gcc dot gnu.org
2024-01-02 16:49 ` pdimov at gmail dot com
2024-01-02 16:51 ` pdimov at gmail dot com
2024-01-03 11:13 ` [Bug c++/113200] " redi at gcc dot gnu.org
2024-01-03 11:23 ` [Bug libstdc++/113200] " redi at gcc dot gnu.org
2024-01-03 12:57 ` redi at gcc dot gnu.org
2024-01-03 13:01 ` redi at gcc dot gnu.org
2024-01-04  1:58 ` de34 at live dot cn [this message]
2024-01-05 10:23 ` cvs-commit at gcc dot gnu.org
2024-01-05 11:46 ` redi at gcc dot gnu.org
2024-01-06 13:40 ` cvs-commit at gcc dot gnu.org
2024-01-11 23:16 ` cvs-commit at gcc dot gnu.org
2024-01-11 23:17 ` redi at gcc dot gnu.org

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