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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Safety of casting from 'long' to 'int'
Date: Tue, 12 May 2026 18:36:43 -0700
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James Kuyper <jameskuyper@alumni.caltech.edu> writes:

> On 2026-05-08 06:43, David Brown wrote:
> ...
>
>> Yes, I have heard that argument before.  I am unconvinced that the
>> "value preserving" choice actually has any real advantages.  I also
>> think it is a misnomer - it implies that "unsigned preserving" would
>> not preserve values, which is wrong.
>
> Unsigned-preserving rules would convert a signed value which might be
> negative to unsigned type more frequently than the value preserving
> rules do.

This statement is wrong.  An "unsigned preserving" promotion rule
converts a signed value to a signed value and an unsigned value to
an unsigned value.  The value being converted stays the same in both
cases.  Both an "unsigned preserving" promotion and a so-called
"value preserving" promotion preserve the value of the operand being
promoted (and converted).