Blocked revisions 81904 via svnmerge

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  r81904 | mark.dickinson | 2010-06-11 21:27:05 +0100 (Fri, 11 Jun 2010) | 4 lines

  Fix possible undefined behaviour from signed overflow in struct module.

  Backport of revisions 81897, 81898 and 81902 from py3k.
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