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Re: How are __LITTLE_ENDIAN__ and __BIG_ENDIAN__ defined?



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.  :)

--
____________________________________________________________
Sean McBride, B. Eng                 email@hidden
Rogue Research                        www.rogue-research.com
Mac Software Developer              Montréal, Québec, Canada


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References: 
 >How are __LITTLE_ENDIAN__ and __BIG_ENDIAN__ defined? (From: Dave Thorup <email@hidden>)
 >Re: How are __LITTLE_ENDIAN__ and __BIG_ENDIAN__ defined? (From: Eric Albert <email@hidden>)



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