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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: "undefined behavior"?
Date: Tue, 18 Jun 2024 17:42:48 -0700
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Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
> Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
>> (I'd like to a future standard require plain char to be unsigned,
>> but I don't know how likely that is.)
>
> It seems unnecessary given that the upcoming C standard
> is choosing to mandate two's complement for all signed
> integer types.

It's less necessary, but I'd still like to see it.

These days, strings very commonly hold UTF-8 data.  The fact that bytes
whose values exceed 127 are negative is conceptually awkward, even if
everything happens to work.  It rarely if ever makes sense to treat a
character value as negative.  (And of course signed char still exists,
or int8_t if you prefer 8 bits vs. CHAR_BIT bits.)

A drawback is that it could break existing (non-portable) code that
assumes plain char is signed.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */