dtoa.c fix from upstream that fixes incorrectly rounded results for certain subnormals that are also halfway cases.

this fixes the first bug described in issue #7743.

in issue 7743).

and exit points.  2. Simplify bigcomp comparison loop.  3. Don't set
ERANGE on _Py_dg_strtod underflow (it was set inconsistently anyway).
4. Remove unused dsign field from BCinfo struct.

private memory allocation scheme in dtoa.c, along with a piece of code
that caches powers of 5 for future use.  This makes it easier to
detect dtoa.c memory leaks with Valgrind or similar tools.

Patch by Stefan Krah.

Fix multiple uses of variable 'L' in _Py_dg_strtod, where one use requires an unsigned long and the other a signed long.  See also r77421.

conversion (see bug 5 in the issue tracker).

Also remove some now unused variables, and add comments clarifying the
possible outputs of the parsing section of _Py_dg_strtod.  Thanks
Eric Smith for reviewing.

Py3K warnings are DeprecationWarning by default this was causing -3 to
essentially be a no-op. Now DeprecationWarning is only silenced if -3 is not
used.

Closes issue #7700. Thanks Ezio Melotti and Florent Xicluna for patch help.

Issue 7632:  fix incorrect rounding for long input strings with values very close to a power of 2.  (See Bug 4 in the tracker discussion.)

Fix off-by-one error introduced in r77483.  I have a test for this, but it currently fails due to a different dtoa.c bug;  I'll add the test once that bug is fixed.

crashes in debug builds, for certain long numeric strings
corresponding to subnormal values.

This was originally suggested by Guido, discussed on the stdlib-sig mailing
list, and given the OK by Guido directly to me. What this change essentially
means is that Python has taken a policy of silencing warnings that are only
of interest to developers by default. This should prevent users from seeing
warnings which are triggered by an application being run against a new
interpreter before the app developer has a chance to update their code.

Closes issue #7319. Thanks to Antoine Pitrou, Ezio Melotti, and Brian Curtin
for helping with the issue.

r77400.

to integer PyArg_Parse* format codes into a TypeError.  Add a
DeprecationWarning for floats passed with the 'L' format code, which
didn't previously have a warning.

Also, add a note to the docs about the better behavior of T_OBJECT_EX as
compared to T_OBJECT.

#7033: add new API function PyErr_NewExceptionWithDoc, for easily giving new exceptions a docstring.

pymath.c to Modules/_math.c.

in a Py_ssize_t, not an int.

arithmetic.