Blocked revisions 77410,77421,77450-77451 via svnmerge

Blocked revisions 77410,77421,77450-77451 via svnmerge

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  r77410 | mark.dickinson | 2010-01-10 13:06:31 +0000 (Sun, 10 Jan 2010) | 1 line

  Remove unused BCinfo fields and an unused macro.
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  r77421 | mark.dickinson | 2010-01-11 17:15:13 +0000 (Mon, 11 Jan 2010) | 1 line

  Change a variable type to avoid signed overflow; replace repeated '19999' constant by a define.
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  r77450 | mark.dickinson | 2010-01-12 22:23:56 +0000 (Tue, 12 Jan 2010) | 4 lines

  Issue #7632: Fix a problem with _Py_dg_strtod that could lead to
  crashes in debug builds, for certain long numeric strings
  corresponding to subnormal values.
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  r77451 | mark.dickinson | 2010-01-12 22:55:51 +0000 (Tue, 12 Jan 2010) | 2 lines

  Issue #7632:  Fix a bug in dtoa.c that could lead to incorrectly-rounded results.
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