Merged revisions 77722 via svnmerge from

Merged revisions 77722 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r77722 | mark.dickinson | 2010-01-24 10:16:29 +0000 (Sun, 24 Jan 2010) | 23 lines

  Merged revisions 77691,77698,77713-77714 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

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    r77691 | mark.dickinson | 2010-01-22 16:18:09 +0000 (Fri, 22 Jan 2010) | 1 line

    Correct typo in comment.
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    r77698 | mark.dickinson | 2010-01-22 17:04:07 +0000 (Fri, 22 Jan 2010) | 3 lines

    Issue #7743:  Fix a potential incorrect rounding bug in dtoa.c (2nd bug
    in issue 7743).
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    r77713 | mark.dickinson | 2010-01-23 20:48:56 +0000 (Sat, 23 Jan 2010) | 3 lines

    Issue #7743:  Add checks for zero inputs to the lshift and mult functions;
    this fixes the first bug described in issue #7743.
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    r77714 | mark.dickinson | 2010-01-23 21:25:53 +0000 (Sat, 23 Jan 2010) | 1 line

    dtoa.c fix from upstream that fixes incorrectly rounded results for certain subnormals that are also halfway cases.
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