[Python-Dev] ssize_t question: longs in header files

[Tim Peters]

[Neal Norwitz]
>  * hash values
> Include/abstract.h:     long PyObject_Hash(PyObject *o);  // also in object.h
> Include/object.h:typedef long (*hashfunc)(PyObject *);

We should leave these alone for now.  There's no real connection
between the width of a hash value and the number of elements in a
container, and Py_ssize_t is conceptually only related to the latter.

As you noted later, there is an unusually strong connection in the
dict implementation, and it's been on my todo list for months to look
into that.  Certainly the struct _dictobject members need to change
from int to Py_ssize_t (including ma_mask), but that can't be done
mechanically (code changes may also be required, and this is one is
much more math- than compiler-warning- driven).

I'll note in passing that the debug-build obmalloc has no idea what to
do with byte counts that don't fit in 4 bytes (it will probably
left-truncate them in its internal debugging records).