Merged revisions 64981 via svnmerge from

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

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  r64981 | mark.dickinson | 2008-07-15 22:55:23 +0100 (Tue, 15 Jul 2008) | 4 lines

  Fix float.from_hex tests.  It appears that Linux/ia64 doesn't like
  computing 2.0**-1074 accurately.  Using ldexp(1.0, -1074) should be
  safer.
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