Compiling for both Intel and PPC CPUs on OSX

Question

I have a MacBook Pro with a 64-bit Intel Core 2 Duo processor, and I'm using gcc (i686-apple-darwin9-gcc-4.0.1) to compile executables which I can run ok on my own machine. Recently someone tried to run my application on a PowerBook G4 and got a 'Bad CPU type in executable' error, which I think is because their CPU is PPC rather than Intel (and also possibly 32 bit not 64 bit)

Is it possible for me to produce binaries that will work across all the various Mac architectures using gcc, and if so what options do I use?

Answer 1

Look at the -arch parameter for gcc Apple docs

Answer 2

You need to look into "Universal Binaries" this is the name given to an app file which runs, with no dynamic recompilation, on both ppc and i386 architectures. As you know .app files (Mac Executables), are in fact archives, which contain, within them, the actual binary application. These can be partitioned in such a way that both the i386 and ppc binaries are contained.

Answer 3

To save yourself and your users future headaches, you should bite the bullet and set up your project in Apple's Xcode. If you follow the defaults, Xcode can take care of all the details of building for multiple architectures, like using the proper -arch flags for gcc, using the correct SDK libraries, compatibility with previous OS X versions, etc etc.