Cannot Install py2cairo on Mac OSX

Question

I am trying to install py2cairo on a framework build (Mac OSX Lion) of python 2.7.3 using brew. I have been unsuccessful this far.

First, I tried a simple

brew install py2cairo

This seems to work only on a non-framework build of python. When I do this on my framework build python faults as soon as I import cairo with an incompatible binary error.

Second, I have tried to build it myself by grabbing it from github and issuing:

python waf configure

This fails with:

Checking for library python2.7           : not found 
Checking for library python2.7           : not found 
Checking for library python2.7           : not found 
Checking for library python27            : not found 
Checking for program python2.7-config    : /usr/local/Cellar/python/2.7.3/bin/python2.7-   config 
Checking for header Python.h             : Could not find the python development headers 
The configuration failed
(complete log in /Users/tobin/tmp/py2cairo/build_directory/config.log)

I have tried everything at: How to install PyCairo 1.10 on Mac OSX with default python but none of this has helped.

It appears to me that this may be failing to find python2.7 library and header file since it is a framework build. Is that possible? I was looking at the brew formula and it appears that framework builds do not get --enable-share set at build time. I'm not sure if that is relevant here - but maybe one possibility.

Anyone other insights would be great. Thanks in advance.

UPDATE:

I discovered that the inability to build py2cairo had to do with the use of the "-march=native" flag by gcc. gcc (4.2.1) on Mac OSX has issues with this. I then reinstalled gcc as well as python. Afterwards when building py2cairo with waf - it was getting "-march=core2" and everything built.

Unfortunately, not all is good yet. I get the same error when I import cairo from my build that I got from the brew version (as mentioned above). The exact error message is:

>>> import cairo
Fatal Python error: Interpreter not initialized (version mismatch?)
Abort trap: 6

and then python exits.

It would now seem that the issue is related to the framework build of python. I tested it without a framework build and it worked fine.

Coorg

It looks like framework builds are shared builds after all. I checked the python27 library and it is a Mach-O 64-bit dynamically linked shared library x86_64. – Coorg

For the record, there are at least three different kinds of Python builds on OS X: non-shared, shared, and framework (an OS X only kind of shared). You might want to take a look at the MacPorts portfile for py27-cairo (macports.org/ports.php?by=name&substr=py27-cairo). MacPorts is often better at dealing with complex ports with many dependencies. – Tristram

I just discovered that waf is getting CFLAGS from python's distutils and the flag "-march=native" is being used. It appears that the apple installed version of gcc does not work with this. At least on my machine it does not - I verified this by attempting to compile a very simple file with it. Still not clear yet where I can control this - or otherwise unset it altogether. – Coorg

Answer 1

So as to not leave this question dangling ... I wanted to follow up with my resolution and learning points:

1. As noted above there was an incompatibility with my version of OSX and a gcc compile flag called -march=native. In a later version it was coming up as -march=core2. This pretty much fixed itself with compiler/version changes after cleaning up my machine.

2. For years I have had quite a mess with all of my various MAC OSX installs - and accepting the "migration option". Two machines ago - I installed the python binaries for versions 2.4, and 2.5, Then eventually went to macports for various reasons. Then eventually went to homebrew. When I went to homebrew I tried to clean things up by hand (but of course this can be challenging). To make matters worse - everytime I have gotten a new mac (2 times) in the last 6 years I take "the migration install" option and this pushes the mess forward and makes it worse. So as I started looking into things further - I had various installs of python, with different versions - mac-native, python-native, mac ports, homebrew, and probably even others too on my system. So my best guess is that cairo was somehow finding one of these and trying to build against it.

I finally solved this by deleting a bunch of old python installs by hand and then starting over with a fresh virtualenv and homebrew install of python 2.7.

WARNING: I don't think that this is the smartest way to go. I was careful not to delete a version of Python that I thought came native with OSX Lion (I think it is 2.6) - but it is not clear how it may potentially effect some other things that may have depended on older mac installs of python. I ended up deleting a 2.3, a 2.4, and two different 2.5s - along with various links in some places. WHAT A MESS! Unless you are absolutely sure of what it is you are doing (which I was not) I would not suggest this approach. I was basically trying to kill 6 years of python install crud that has collected.

To be safe I probably should have started with a fresh OSX Lion install and then added my homebrew version and went from there. I will likely do this in the near future.

Coorg