[chboss]

Hello all


I have a question regarding compiliation using GCC 4 that comes with the latest Xcode tools 2.1:

I use a G4 based mac running "Tiger" 10.4.2 to build a binary on the command line.
So far I have been sucessfull when using -mcpu=G4 or -mcpu=7450
Now I would like to build an optimized binary for the G5. I use the same optimization flags execpt: -mcpu=G5.

But I always get an error message during configuration that I should use --host if I want to cross compile?
I expected that compiling for a G5 processor on a G4 based hardware should be no problem since it is the same operating system....


Any help or pointer to some information how to solve this problem is appreciated.

Chris

[szymczyk]

If you want to build a 64-bit binary for the G5, you must tell the compiler to build for the 64-bit PowerPC architecture. The command-line setting to use is ARCHS, and the value to use is ppc64.

If you just want the code to run best on a G5, you can use the -mtune setting. The -mtune setting schedules the instructions so they run fastest on the processor you specify.

[Detrius]

Originally Posted by szymczyk

If you want to build a 64-bit binary for the G5, you must tell the compiler to build for the 64-bit PowerPC architecture. The command-line setting to use is ARCHS, and the value to use is ppc64.

If you just want the code to run best on a G5, you can use the -mtune setting. The -mtune setting schedules the instructions so they run fastest on the processor you specify.

If you are using Xcode, you would manually enter ppc and ppc64 as the platforms to compile for--instead of ppc and i386. See 'man 3 arch' for a list of the supported architectures.