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From: James Kuyper <jameskuyper@alumni.caltech.edu>
Newsgroups: comp.lang.c
Subject: Re: What is your opinion about unsigned int u = -2 ?
Date: Sun, 11 Aug 2024 16:53:20 -0400
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On 8/11/24 16:08, Vir Campestris wrote:
....
> "Converting -1 to an unsigned type always sets all the bits"
> 
> In any normal twos complement architecture that's the case. But there 
> are a few oddballs out there where -1 is +1, except that the dedicated 
> sign bit is set.

There may be hardware where that is true, but a conforming
implementation of C targeting that hardware cannot use the hardware's
result. It must fix up the result produced by the hardware to match the
result required by the C standard.