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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/114537] bit_cast does not work NSDMI of bitfields
Date: Mon, 01 Apr 2024 13:54:21 +0000	[thread overview]
Message-ID: <bug-114537-4-akhzMbPlZp@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114537-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114537

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Fedor Chelnokov from comment #1)
> Probably related:
> ```
> #include <bit>
> 
> struct A { int a: 7; };
> 
> static_assert( 1 == std::bit_cast<A>(std::bit_cast<int>(A{1})).a );
> ```
> It looks valid and accepted by MSVC, but GCC prints:
> error: '__builtin_bit_cast' accessing uninitialized byte at offset 0
> 
> Online demo: https://gcc.godbolt.org/z/3W5onY955

That is unrelated and gcc is actually correct there see pr 99637.

  parent reply	other threads:[~2024-04-01 13:54 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-31 19:33 [Bug c++/114537] New: " pinskia at gcc dot gnu.org
2024-04-01  9:40 ` [Bug c++/114537] " fchelnokov at gmail dot com
2024-04-01 13:54 ` pinskia at gcc dot gnu.org [this message]
2024-04-03 15:10 ` jakub at gcc dot gnu.org
2024-04-04  8:48 ` cvs-commit at gcc dot gnu.org
2024-04-05 18:44 ` fchelnokov at gmail dot com
2024-04-21  4:08 ` cvs-commit at gcc dot gnu.org
2024-06-11 10:37 ` cvs-commit at gcc dot gnu.org
2024-06-11 10:57 ` jakub at gcc dot gnu.org
2024-06-20 13:22 ` cvs-commit at gcc dot gnu.org
2024-06-20 13:39 ` jakub at gcc dot gnu.org

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