Merged revisions 82966 via svnmerge from

Merged revisions 82966 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r82966 | stefan.krah | 2010-07-19 14:36:57 +0200 (Mon, 19 Jul 2010) | 13 lines

  Issue #9036: Throughout the code base, Py_CHARMASK is used on 8-bit wide
  signed/unsigned chars or on integers directly derived from those. In all
  cases, it could be replaced by a simple cast to (unsigned char). Reasons
  for the change:

    a) Make the comment more explicit.

    b) If char is unsigned, the cast is optimized away.

    c) If char is unsigned, gcc emits spurious "array subscript
       has type 'char'" warnings.
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