Issue #1706863: Fixed "'NoneType' object has no attribute 'rfind'" error when sqlite libfile not found.

  UnboundLocalError: local variable 'serv' referenced before assignment

Fixed a comment to C89 style as of http://drj11.wordpress.com/2008/10/02/python-and-bragging-about-c89/

installer.

FreeBSD 7's underlying malloc() is behaves differently to earlier versions
and seriously overcommits available memory on amd64.  This may affect
other 64bit platforms in some circumstances, so the scale of the
problematic test is wound back.

Patch by Mark Dickinson, reviewed by Martin von Loewis.

calling fork() from a child thread.  This disables that unit test (with a note
printed to stderr) on those platforms.

A caveat about buggy platforms is added to the os.fork documentation.

Fix suggested by Amaury Forgeot d'Arc.
Closes issue #4003.

reviewed by Amaury

patch by Victor Stinner
reviewed by myself and Brett

true singleton object.

Reviewed by Gregor Lingl.

timer that did not return a float and a timer was still running when the
Profiler object was garbage collected.

Fixes issue 3895.
Code review by Benjamin Peterson.