Re: How are __LITTLE_ENDIAN__ and __BIG_ENDIAN__ defined?
Re: How are __LITTLE_ENDIAN__ and __BIG_ENDIAN__ defined?
- Subject: Re: How are __LITTLE_ENDIAN__ and __BIG_ENDIAN__ defined?
- From: Clark Cox <email@hidden>
- Date: Wed, 16 Nov 2005 10:49:46 -0500
On 11/16/05, Sean McBride <email@hidden> wrote:
> On 2005-11-15 16:27, Eric Albert said:
>
> >> Also, since only one of them is defined would it be better to use
> >> #if as I did above or should I use #ifdef?
> >
> >In general, I prefer #if to #ifdef just because that protects you if
> >someone writes code like this:
> >
> >#if __LITTLE_ENDIAN__
> >#define __BIG_ENDIAN__ 0
> >#endif
>
> OTOH, some compilers, like CodeWarrior, will (optionally of course) give
> a warning using an undefined macro in an #if test:
>
> Warning : undefined macro '__LITTLE_ENDIAN__' used in #if or #elif conditional
> HelloWorld.c line 11 #if __LITTLE_ENDIAN__
>
> I'm not a language lawyer, so I'm not sure if it's defined behaviour to
> do an #if test on an undefined macro. No doubt someone will pipe up. :)
No doubt :)
Yes, it is well defined.
"#if UNDEFINED_MACRO"
is the same as:
"#if 0"
--
Clark S. Cox III
email@hidden
http://clarkcox3.livejournal.com/
http://homepage.mac.com/clarkcox3/
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Xcode-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden