From: Alejandro Colomar <alx.manpages@gmail.com>
To: Joseph Myers <joseph@codesourcery.com>
Cc: gcc@gcc.gnu.org, GNU C Library <libc-alpha@sourceware.org>,
Yann Droneaud <ydroneaud@opteya.com>
Subject: Re: stdc_bit_ceil(3) and wrapping
Date: Fri, 30 Dec 2022 22:01:35 +0100 [thread overview]
Message-ID: <d6b60e0e-dcb3-c18a-d3fb-605d10522eb7@gmail.com> (raw)
In-Reply-To: <e08827ea-1251-917a-a155-817f5d90c43d@codesourcery.com>
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On 12/30/22 21:56, Joseph Myers wrote:
> On Fri, 30 Dec 2022, Alejandro Colomar via Gcc wrote:
>
>> For the C standard, shifts have wrap around semantics for unsigned types:
>
> Only if the shift count is nonnegative and strictly less than the width of
> the type. This is about shifting by an amount equal to the width of the
> type, which has undefined behavior.
Ahhh, right, I forgot that detail. Yep, I need to special-case then.
Thanks!
--
<http://www.alejandro-colomar.es/>
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next prev parent reply other threads:[~2022-12-30 21:01 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-12-30 19:53 Alejandro Colomar
2022-12-30 20:18 ` Yann Droneaud
2022-12-30 20:33 ` Alejandro Colomar
2022-12-30 22:33 ` Alejandro Colomar
2023-01-06 20:08 ` Alejandro Colomar
2022-12-30 20:47 ` Alejandro Colomar
2022-12-30 20:38 ` Joseph Myers
2022-12-30 20:46 ` Alejandro Colomar
2022-12-30 20:56 ` Joseph Myers
2022-12-30 21:01 ` Alejandro Colomar [this message]
2022-12-30 21:06 ` Alejandro Colomar
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