Re: [RFC][PATCH] A generic boolean

[Andreas Schwab <schwab@suse.de>]

Jes Sorensen <jes@sgi.com> writes:

> Alan Cox wrote:
>> Ar Gwe, 2006-08-04 am 16:35 +0200, ysgrifennodd Jes Sorensen:
>>> The proposed patch makes it u1 - if we end up with arch specific
>>> defines, as the patch is proposing, developers won't know for sure what
>>> the size is and will get alignment wrong. That is not fine.
>>
>> The _Bool type is up to gcc implementation details.
>
> Which is even worse :(

It's part of the ABI, just like any other C type.

>>> If we really have to introduce a bool type, at least it has to be the
>>> same size on all 32 bit archs and the same size on all 64 bit archs.
>>
>> You don't use bool for talking to hardware, you use it for the most
>> efficient compiler behaviour when working with true/false values.
>
> Thats the problem, people will start putting them into structs, and
> voila all alignment predictability has gone out the window.

Just like trying to predict the alignment of any other C type.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."