[SciPy-Dev] Getting Scipy's weave to work reliably on Windows

[Chris Ball]

Hi,

While testing Scipy's weave on several different Windows installations, I came 
across some problems with spaces in paths that often prevent weave from working. 
I can see a change that could probably get weave working on most Windows 
installations, but it is a quick hack. Someone knowledgeable about distutils 
(and numpy.distutils?) might be able to help me fix this properly. Below I 
describe three common problems with weave on Windows, in the hope that this 
information helps others, or allows someone to suggest how to fix the spaces-in-
paths problem properly.

I think there are three common problems that stop weave from working on Windows. 
The first is not having a C compiler. Both Python(x,y) and EPD provide a C 
compiler that seems to work fine, which is great!

The second problem is that if weave is installed to a location with a space in 
the path, linking fails. There is already a scipy bug report about this 
(http://projects.scipy.org/scipy/ticket/809). I've just commented on that 
report, saying the problem appears to be with distutils, and there is already a 
Python bug report about it (http://bugs.python.org/issue4508). Maybe someone 
could close this scipy bug, or link it to the Python one somehow? In any case, 
when using Python(x,y) or EPD, this bug will not show up if the default 
installation locations are accepted. So, that's also good news!

The third problem is that if the Windows user name has a space in it (which in 
my experience is quite common), compilation fails. Weave uses the user name to 
create a path for its "intermediate" and "compiled" files. When the compilation 
command is issued, the path with the space in it is also not quoted. Presumably 
that is another error in distutils (or numpy.distutils)? Unfortunately I wasn't 
able to pinpoint what function is failing to quote strings properly, because I 
couldn't figure out the chain that leads to the compiler being called. However, 
I can avoid the problem by removing spaces from the user name in weave itself 
(catalog.py):

def whoami():
    """return a string identifying the user."""
    return (os.environ.get("USER") or os.environ.get("USERNAME") or 
"unknown").replace(" ","")

(where I have added .replace(" ","") to the existing code).

I realize this isn't the right solution, so if someone could help to guide me to 
the point where quoting should occur, that would be very helpful. Otherwise, is 
there any chance of applying a hack like this so weave can work reliably on 
Windows?

Thanks,
Chris