Backport fixes for the code that decodes octal escapes (and for PyString
also hex escapes) -- this was reaching beyond the end of the input string
buffer, even though it is not supposed to be \0-terminated.
This has no visible effect but is clearly the correct thing to do.
(In 3.0 it had a visible effect after removing ob_sstate from PyString.)
Also fixes #1098.

 (backport)

with %G.
 (backport from rev. 56298)

Fix a bug when there was a newline in the string expandtabs was called on.
This also catches another condition that can overflow.

a large width is passed on 32-bit platforms.  Found by Google.

It would be good for people to review this especially carefully and verify
I don't have an off by one error and there is no other way to cause overflow.

* unified the way intobject, longobject and mystrtoul handle
  values around -sys.maxint-1.

* in general, trying to entierely avoid overflows in any computation
  involving signed ints or longs is extremely involved.  Fixed a few
  simple cases where a compiler might be too clever (but that's all
  guesswork).

* more overflow checks against bad data in marshal.c.

* 2.5 specific: fixed a number of places that were still confusing int
  and Py_ssize_t.  Some of them could potentially have caused
  "real-world" breakage.

* list.pop(x): fixing overflow issues on x was messy.  I just reverted
  to PyArg_ParseTuple("n"), which does the right thing.  (An obscure
  test was trying to give a Decimal to list.pop()... doesn't make
  sense any more IMHO)

* trying to write a few tests...

Partially from SF patch #1551339, but also taken from head.

  a unicode string in a build with wide unicode (UCS-4) support.

I will forward port to 2.6.  Can someone backport to 2.4?

Replace UnicodeDecodeErrors raised during == and !=
compares of Unicode and other objects with a new
UnicodeWarning.

All other comparisons continue to raise exceptions.
Exceptions other than UnicodeDecodeErrors are also left
untouched.

I modified this patch some by fixing style, some error checking, and adding
XXX comments.  This patch requires review and some changes are to be expected.
I'm checking in now to get the greatest possible review and establish a
baseline for moving forward.  I don't want this to hold up release if possible.

Many (all?) of these could be backported.

Also improve error message on overflow.

to enable use from stringobject

where appropriate

 - Check the correct variable (str_obj, not str) for NULL
 - sep_len was already verified it wasn't 0

find

find helpers; updated unicodeobject to use stringlib_count

feel free to add more tests and improve the documentation.

length (thanks, neal!).  and yes, I've verified that this doesn't
slow things down ;-)

~15% faster for the current tests (which is noticable faster than a corre-
sponding find call).  thanks to neal-who-never-sleeps for the tip.

feel free to improve the documentation and the docstrings.

Now using PyInt_FromSsize_t.