Don't download sources that won't be used.

Issue #24989

set beyond size.  Based on patch by John Leitch.

This modifies the behavior of the '-e' flag to PCbuild\build.bat: when '-e'
is not supplied, no attempt will be made to build extension modules that
require external libraries, even if the external libraries are present.

Also adds '--no-<module>' flags to PCbuild\build.bat, where '<module>' is
one of 'ssl', 'tkinter', or 'bsddb', to allow skipping just those modules
(if '-e' is given).

This makes it possible to pass more than 4 tests by name through
Tools\buildbot\test.bat

set beyond size.  Based on patch by John Leitch.

The ICC compiler doesn't seem to support defined() in macro expansion. Example
of warning:

warning #3199: "defined" is always false in a macro expansion in Microsoft mode

Reported by John Leitch and Bryce Darling, patch by Raymond Hettinger.

As suggested by Steve Dower and approved by Stefan Krah.

collection) in collections.OrderedDict constructor.

Patch reviewed by Serhiy Storchaka.

Handle PyCapsule_Import() failure (exception) in PyCodec_NameReplaceErrors():
return immedialty NULL.

The support import is not needed in Python 3.5

I was not supposed to commit the function with the name pymonotonic_new(). I
forgot to rename it.

Don't check anymore at runtime that the monotonic clock doesn't go backward.
Yes, it happens. It occurs sometimes each month on a Debian buildbot slave
running in a VM.

The problem is that Python cannot do anything useful if a monotonic clock goes
backward. It was decided in the PEP 418 to not fix the system, but only expose
the clock provided by the OS.

BaseTest now ensures that unittest.TestCase.assertWarns() uses the same
warnings module than warnings.catch_warnings(). Otherwise,
warnings.catch_warnings() will be unable to remove the added filter.

when the test is interrupted (or fail).

Mention also the detected GDB version on verbose mode and on error (if the
major version is smaller than 7).

Also fixes error in 'kill' target (already fixed in 2.7, somehow the fix
didn't make it to this branch).