Re: determining 32 v. 64 bit compilatio

[Peter O'Gorman]

On 06/30/2010 03:55 AM, Wesley Smith wrote:
> > > I don't disagree, but let's consider this an academic exercise at this
> > > point.  I'd actually like to know how to do this regardless of whether
> > > it violates anyones code sensibilities.
> >
> > Before we answer your question, I'd like a clarification: what would be the 
> > proper setting on OS X for you, when the compiler generates both 32-bit and 
> > 64-bit code in the same object?
> >
> > In other words, are you looking for a configuration variable that changes the 
> > way your code is compiled, or are you looking for a way to change the name of 
> > the files that are generated by the compiler?
>
> On OSX, I'm looking for something that adapts to the -arch i386 -arch
> x86_64 flags, so it should depend on the compiler settings, not
> generate them.  Looking further into the library (which is open source
> fortunately), I find where the flag is used:


On OS X either use #ifdef __x86_64__ or __LP64__ (the latter is also 
defined for ppc64) which are defined by the compiler.

If you want to limit the check for OS X, check for __APPLE__ too.

Peter