Merged revisions 67494 via svnmerge from

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

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  r67494 | jeffrey.yasskin | 2008-12-02 22:46:45 -0800 (Tue, 02 Dec 2008) | 5 lines

  Speed up Python (according to pybench and 2to3-on-itself) by 1-2% by caching
  whether any thread has tracing turned on, which saves one load instruction in
  the fast_next_opcode path in PyEval_EvalFrameEx().  See issue 4477.
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