Blocked revisions 74031-74033 via svnmerge

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  r74031 | alexandre.vassalotti | 2009-07-17 00:24:45 -0400 (Fri, 17 Jul 2009) | 2 lines

  Use AC_CHECK_SIZEOF to find the size of off_t, pthread_t and time_t.
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  r74032 | alexandre.vassalotti | 2009-07-17 00:59:05 -0400 (Fri, 17 Jul 2009) | 4 lines

  Rename the useless AC_INCLUDES_DEFAULT and protect the includes.

  This is mostly an aesthetic change.
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  r74033 | alexandre.vassalotti | 2009-07-17 01:26:39 -0400 (Fri, 17 Jul 2009) | 8 lines

  Cache the results of all runtime checks.

  This will be helpful to people who want to compile Python with a
  cross-compiler. Now you can upload the configure script on your host
  machine, run it with caching enabled, and download the cached results
  on your build machine.
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