Re: [RFC][PATCH] A generic boolean

Andreas Schwab
2006-08-04T16:00:50Z

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.

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Andreas Schwab, SuSE Labs, schwab@suse.de
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