Merged revisions 75022 via svnmerge from

Merged revisions 75022 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r75022 | ronald.oussoren | 2009-09-22 21:27:44 +0200 (Tue, 22 Sep 2009) | 8 lines

  Half of the fix for issue 6957: ensure that distutils
  ignores the '-isysroot' option on OSX when the
  corresponding SDK is not installed.

  This ensures that the user can compile extensions
  on OSX 10.6 using the Python.org installer and a
  default installation of Xcode.
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