python easy_install fails with “assembler for arch

问题:

bash-3.2$ sudo easy_install appscript  
Password:  
Searching for appscript  
Reading http://pypi.python.org/simple/appscript/  
Reading http://appscript.sourceforge.net  
Best match: appscript 1.0.0  
Downloading http://pypi.python.org/packages/source/a/appscript/appscript-1.0.0.tar.gz#md5=6619b637037ea0f391f45870c13ae38a  
Processing appscript-1.0.0.tar.gz  
Running appscript-1.0.0/setup.py -q bdist_egg --dist-dir /tmp/easy_install-C4d1az/appscript-1.0.0/egg-dist-tmp-yVTHww  
/usr/libexec/gcc/powerpc-apple-darwin10/4.2.1/as: assembler (/usr/bin/../libexec/gcc/darwin/ppc/as or /usr/bin/../local/libexec/gcc/darwin/ppc/as) for architecture ppc not installed  
Installed assemblers are:  
/usr/bin/../libexec/gcc/darwin/x86_64/as for architecture x86_64  
/usr/bin/../libexec/gcc/darwin/i386/as for architecture i386  

I'm a pretty big noob at this stuff (I've learned to use python and unix a bit, but I've never had to deal with installation.) Earlier I was getting an error related to gcc-4.2 not being found, and I found some posts that recommended reinstalling XCode. I went with 4.0 (bad choice?) and now I get this. I've got no idea what to do at this point.

回答1:

This happened for me after having upgraded to XCode 4; I haven't had time to figure out what went wrong during the upgrade (or whether this is the intended behaviour), but the following workaround works for me:

sudo env ARCHFLAGS="-arch i386" easy_install whatever

The ARCHFLAGS trick works with setup.py as well:

env ARCHFLAGS="-arch i386 -arch x86_64" python setup.py install

回答2:

I found another solution here which solves the problem once and for all. It turns out XCode4 still has the ppc assembler. You just need a symlink to it in the right place:

$ sudo ln -s /Developer/Platforms/iPhoneOS.platform/Developer/usr/libexec/gcc/darwin/ppc /Developer/usr/libexec/gcc/darwin
$ sudo ln -s /Developer/Platforms/iPhoneOS.platform/Developer/usr/libexec/gcc/darwin/ppc /usr/libexec/gcc/darwin

Fixed the problem for me with XCode4 installed on Snow Leopard.

EDIT: I tried other solutions, which worked in some cases, but invariably encountered a package that hardcoded the PPC requirement somewhere. Providing the PPC assembler got rid of all these problems once and for all.

回答3:

For me, the key was the ppc assembler, not the ARCHFLAGS stuff. But, the suggestion above didn't work; I didn't have the files in those locations. But with some tinkering and poking around, I found that I did have the ppc assember at /usr/bin/as. I first tried sudo ln -s /usr/bin/as /usr/libexec/as/ppc/as, but that failed (something about could not fork process...??). So I ended up just doing sudo cp /usr/bin/as /usr/libexec/as/ppc/as, and that worked (I think I had to do some sudo mkdirs along that path, as well).

回答4:

Using the system Pythons on Mac OS X 10.6, you'll need to have the gcc-4.2 from the Apple Xcode Developer Tools installed to build extension modules, like with Appscript. Other products may need the Xcode gcc-4.0 so you should install them both. They co-exist just fine.