Merged revisions 78082,78086 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

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  r78082 | mark.dickinson | 2010-02-07 13:01:56 +0000 (Sun, 07 Feb 2010) | 1 line

  Add missing global declarations for 'overflowok'; remove 'overflowrequired', which is no longer needed.
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  r78086 | mark.dickinson | 2010-02-07 13:09:52 +0000 (Sun, 07 Feb 2010) | 1 line

  Actually raise on failure, instead of doing nothing.
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