[gecode-users] compiling for 32bits on snow leopard

[Christopher Jefferson]

On 31 Oct 2009, at 14:06, Guido Tack wrote:

> Hi Denys,
>
> Denys Duchier wrote:
>> A colleague of mine has been having quite a bit of difficulty trying
>> to
>> install Gecode on her brand new Mac.  When compiling from sources for
>> 32bits: I added -m32 to CFLAGS and CXXFLAGS, but it turns out that's
>> not
>> sufficient.  I had to tweak the Makefile and add -m32 also to
>> DLLFLAGS.
>>
>> Maybe there's a better way, but I thought I'd pass on the info.
>> Perhaps
>> you can tweak configure to make this easier.  Me, I don't know macs
>> from
>> a hole in the ground, so I won't try.
>
> I don't think m32 or m64 should be necessary on Mac OS.  Did she use
> the configure option -with-architectures=i386 in order to select 32-
> bit mode?  That's the recommended way, and in my experience that's all
> that is needed.  You can give any architecture there, e.g. for the
> binary packages I use -with-architectures=i386,x86_64,ppc in order to
> get a "universal binary".

Just in case you are unaware, one reason you might be having a problem  
is that on snow leopard, the default of gcc has switched from always  
32 bit to however many bits your CPU has. Most, but not all, intel  
macs are 64-bit.

Chris