Re: [Help-gsl] GSL and XCode

[Jonny Taylor]

> The second problem is more difficult. Perhaps the -arch ppc is the problem.  
> I removed ppc from the build options and left only i386.  That solved the 
> problem (I also included the -lstdc++ flag).  
...
>     /Developer/usr/bin/gcc-4.0 -o 
> /Users/rangel/doc/src/bessel/build/bessel.build/Release/bessel.build/Objects-normal/ppc/bessel
>  -L/Users/rangel/doc/src/bessel/build/Release 
> -L/Developer/SDKs/MacOSX10.5.sdk/usr/local/lib 
> -F/Users/rangel/doc/src/bessel/build/Release -filelist 
> /Users/rangel/doc/src/bessel/build/bessel.build/Release/bessel.build/Objects-normal/ppc/bessel.LinkFileList
>  -arch ppc -mmacosx-version-min=10.5 -lgsl -lgslcblas -lm -lstdc++ -isysroot 
> /Developer/SDKs/MacOSX10.5.sdk
> ld: warning in /Developer/SDKs/MacOSX10.5.sdk/usr/local/lib/libgsl.dylib, 
> file is not of required architecture
> ld: warning in 
> /Developer/SDKs/MacOSX10.5.sdk/usr/local/lib/libgslcblas.dylib, file is not 
> of required architecture

Yep, so what's happening here is that when you build a universal binary (x86 
and ppc) Xcode effectively does two completely separate builds, one for x86 and 
one for ppc. The ppc cannot link against GSL because the GSL library has been 
compiled for x86 only (i.e. no ppc) and hence is indeed "not of the required 
architecture". You should be able to sort that if you really do want ppc 
support, though I can't off the top of my head tell you what options you will 
need to pass to the GCC configure command.

Cheers
Jonny