Lowered the recursion limit on compares to 60 (one recursion depth can
take a whopping 2K of stack space when running test_b1!)

types (i.e. Py_uintptr_t, our spelling of C9X's uintptr_t).  ANSI
specifies that pointer compares other than == and != to non-related
structures are undefined.  This quiets an Insure portability warning.

This was a misleading bug -- the true "bug" was that hash(x) gave an error
return when x is an infinity.  Fixed that.  Added new Py_IS_INFINITY macro to
pyport.h.  Rearranged code to reduce growing duplication in hashing of float and
complex numbers, pushing Trent's earlier stab at that to a logical conclusion.
Fixed exceedingly rare bug where hashing of floats could return -1 even if there
wasn't an error (didn't waste time trying to construct a test case, it was simply
obvious from the code that it *could* happen).  Improved complex hash so that
hash(complex(x, y)) doesn't systematically equal hash(complex(y, x)) anymore.

Closes Patch #101065.

marked my*.h as obsolete

Leave the actual #define in for API compatibility.

comments, docstrings or error messages. I fixed two minor things in
test_winreg.py ("didn't" -> "Didn't" and "Didnt" -> "Didn't").

There is a minor style issue involved: Guido seems to have preferred English
grammar (behaviour, honour) in a couple places. This patch changes that to
American, which is the more prominent style in the source. I prefer English
myself, so if English is preferred, I'd be happy to supply a patch myself ;)

need to be cleared.

add macros for backwards compatibility with C source

  strings, instead of the default encoding.
  (see "minidom" thread for discussion, and also patch #100706)

This is now checked and the error passed on to the caller.

to 8-bit strings, using the default encoding.

The common technique for printing out a pointer has been to cast to a long
and use the "%lx" printf modifier. This is incorrect on Win64 where casting
to a long truncates the pointer. The "%p" formatter should be used instead.

The problem as stated by Tim:
> Unfortunately, the C committee refused to define what %p conversion "looks
> like" -- they explicitly allowed it to be implementation-defined. Older
> versions of Microsoft C even stuck a colon in the middle of the address (in
> the days of segment+offset addressing)!

The result is that the hex value of a pointer will maybe/maybe not have a 0x
prepended to it.


Notes on the patch:

There are two main classes of changes:
- in the various repr() functions that print out pointers
- debugging printf's in the various thread_*.h files (these are why the
patch is large)


Closes SourceForge patch #100505.

errors in some of the hash algorithms. For exmaple, in float_hash and
complex_hash a certain part of the value is not included in the hash
calculation. See Tim's, Guido's, and my discussion of this on
python-dev in May under the title "fix float_hash and complex_hash for
64-bit *nix"

(2) The hash algorithms that use pointers (e.g. func_hash, code_hash)
are universally not correct on Win64 (they assume that sizeof(long) ==
sizeof(void*))

As well, this patch significantly cleans up the hash code. It adds the
two function _Py_HashDouble and _PyHash_VoidPtr that the various
hashing routine are changed to use.

These help maintain the hash function invariant: (a==b) =>
(hash(a)==hash(b))) I have added Lib/test/test_hash.py and
Lib/test/output/test_hash to test this for some cases.

reported by Mark Hammon

For more comments, read the patches@python.org archives.
For documentation read the comments in mymalloc.h and objimpl.h.

(This is not exactly what Vladimir posted to the patches list; I've
made a few changes, and Vladimir sent me a fix in private email for a
problem that only occurs in debug mode.  I'm also holding back on his
change to main.c, which seems unnecessary to me.)

Improvements:
- does no longer need any extra memory
- has no relationship to tstate
- works in debug mode
- can easily be modified for free threading (hi Greg:)

Side effects:
Trashcan does change the order of object destruction.
Prevending that would be quite an immense effort, as
my attempts have shown. This version works always
the same, with debug mode or not. The slightly
changed destruction order should therefore be no problem.

Algorithm:
While the old idea of delaying the destruction of some
obejcts at a certain recursion level was kept, we now
no longer aloocate an object to hold these objects.
The delayed objects are instead chained together
via their ob_type field. The type is encoded via
ob_refcnt. When it comes to the destruction of the
chain of waiting objects, the topmost object is popped
off the chain and revived with type and refcount 1,
then it gets a normal Py_DECREF.

I am confident that this solution is near optimum
for minimizing side effects and code bloat.

Note that comparisons of deeply nested objects can still dump core in
extreme cases.

* TypeErrors during comparing of mixed type arguments including
  a Unicode object are now masked (just like they are for all
  other combinations).

to prevent possible buffer overruns.

Added "better safe than sorry" patch to the new
trashcan code in object.c, to ensure that tstate
is not touched when it might be undefined.

Added wrapping macros to dictobject.c, listobject.c, tupleobject.c,
frameobject.c, traceback.c that safely prevends core dumps
on stack overflow. Macros and functions in object.c, object.h.
The method is an "elevator destructor" that turns cascading
deletes into tail recursive behavior when some limit is hit.

compilation on NT Alpha.  Mostly added casts etc.

previous output.  Call clearerr() to prevent past errors affecting our
ferror() test later, in PyObject_Print().  Suggested by Marc Lemburg.

before calling it.  This check was there when the objects were of the
same type *before* coercion, but not if they initially differed but
became the same *after* coercion.

the type names), make sure that numeric objects are considered smaller
than all other objects, by forcing their name to "".