[TUHS] v7 K&R C

Brad Spencer brad at anduin.eldar.org
Sun May 17 06:35:24 AEST 2020

Paul Winalski <paul.winalski at gmail.com> writes:

> On 5/15/20, Warner Losh <imp at bsdimp.com> wrote:
>> arm has been the biggest outlier in terms of unsigned char. In FreeBSD,
>> this has been the second largest source of bugs with the platform... the
>> OABI weird alignment requirements being the first (thankfully behind us)...
> Why did the implementers of the Unix ABI for ARM decide to have char
> be unsigned?  Was there an architectural reason for it?
> -Paul W.

My understanding is that it is a lot more efficient to use unsigned char
on arm.  You can make gcc, for example, deal with this, but it costs.  I
remember having to tell gcc to deal with it when I ported the Doom
engine to a StrongARM processor device under NetBSD many years ago.  I
mostly remember the code running well enough, but it was larger.

Brad Spencer - brad at anduin.eldar.org - KC8VKS - http://anduin.eldar.org

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