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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Abstract Syntax Tree for C programs
Date: Fri, 31 May 2019 13:14:05 -0700
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Richard Damon <Richard@Damon-Family.org> writes:
[...]
> When the committee had to decide what to do, they had 3 main choices for
> the type of unsigned op signed, make it unsigned, make it signed, leave
> it unspecified/implementation dependent. They wrestled with this
> decision, and decided that unsigned preserving was the best choice. Many
> people disagreed with that choice, but many would have disagreed with
> any choice they made, and not making a choice, would have been the
> choice that most would have disagreed with.

Correction: C's rules (since ANSI C89) are value preserving, not
unsigned preserving.

For example, adding two unsigned char or unsigned short values yields a
(signed) int result (if UCHAR_MAX <= INT_MAX or USHRT_MAX <= INT_MAX,
respectively).

See the C99 Rationale, section 6.3.1.1.
http://www.open-std.org/jtc1/sc22/wg14/www/C99RationaleV5.10.pdf

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */