[Boost-build] [Boost]Patch python.jam to avoid feature already defined error

From: K. Noel Belcourt (kbelco_at_[hidden])
Date: 2008-03-11 12:38:50

Hi,

The user-config.jam I use for nightly testing has multiple python  
toolsets configured, as follows:

using python
   : 2.5
   : /home/kbelco/bin/python/linux-32
   ;

using python
   : 2.4
   : /usr/local/python/2.4.4
   ;

using python
   : 2.3
   : /usr/local/python/2.3.5
   ;

The nightly tests that use this configuration file are failing  
because pythonpath is being redefined in the python.jam init rule,  
here's the error message:

/var/scratch2/boost/tools_bb/build/feature.jam:127: in  
feature.feature from module feature
error: feature already defined:
error: in feature declaration:
error: feature "pythonpath" : : "free" "optional" "path"
/var/scratch2/boost/tools_bb/tools/python.jam:118: in python.init  
from module python

I've attached a patch to ensure pythonpath is only defined once, no  
matter how many times the init rule is called.  If there's no  
objection, I'd like to get this committed so our Linux based tests  
start running again.

-- Noel