[flext] Compilation on MacOS 10.7

[Stefano Papetti]

Dear all,

just for the record, this is what I have found on Lion, compiling from 
command line with flext build system and the default LLVM gcc 4.2:

* Compilation against Pd 0.43-2:
Since the current version of Pd is still 32 bit, I forced 32 bit 
compilation only in config-mac-pd-gcc.txt (ARCH=i386). The externals 
work well in Pd and Pd extended 0.42-5.
If not using ARCH or using ARCH=i386 x86_64, Pd complains about wrong 
architecture when loading an external.
Compilation with ARCH=i386 x86_64 works, but it doesn't currently make 
sense.

* Compilation against MaxSDK-5.1.7:
If not using ARCH (i.e. compile only for the current architecture), or 
using ARCH=i386 x86_64 in config-mac-max-gcc.txt flext DOES NOT build 
(i.e. error while compiling 64 bit).
-> It is necessary to force 32 bit compilation using ARCH=i386.
32 bit externals work in Max6.

* Compilation against MaxSDK-6.0.4:
Same as above except for:
32 bit externals DO NOT work in Max6 (Max either freezes or crashes).

Best,
Stefano