Issue 1281408: Py_BuildValue k format units don't work with big values (original) (raw)

Created on 2005-09-03 22:12 by moese, last changed 2022-04-11 14:56 by admin. This issue is now closed.

Messages (7)
msg26200 - (view)	Author: Moese (moese)	Date: 2005-09-03 22:12
Python 2.4 on Windows XP SP2 Consider this code: unsigned long x = 0xaabbccdd; PyObject* v = Py_BuildValue("k", x); unsigned long y = PyLong_AsUnsignedLong(v); y will be equal with -1 because PyLong_AsUnsignedLong will raise an OverflowError since Py_BuildValue doesn't create a long for the "k" format unit, but an int which will be interpreted as a negative number. The K format seems to have the same error, PyLong_FromLongLong is used instead of PyLong_FromUnsignedLongLong. The do_mkvalue function from mod_support.c must be fixed to use PyLong_FromUnsignedLong instead of PyInt_FromLong for "k". Also, the BHLkK format units for Py_BuildValue should be documented. In my Python 2.4 manual they do not appear.
msg26201 - (view)	Author: Georg Brandl (georg.brandl) *	Date: 2005-09-14 20:02
Logged In: YES user_id=1188172 I think you're right. Do you too, Martin?
msg26202 - (view)	Author: Martin v. Löwis (loewis) *	Date: 2005-09-18 08:59
Logged In: YES user_id=21627 I'm not sure what it should do: the other option would be to create an int if it fits, else a long. For 2.4.x atleast, this would give better backwards compatibility given the status quo. I certainly agree that the documentation should be updated. Patches are welcome.
msg26203 - (view)	Author: Georg Brandl (georg.brandl) *	Date: 2005-09-18 10:07
Logged In: YES user_id=1188172 Attaching patch (including doc changes). For I and k, it creates an int if it fits, else a long.
msg26204 - (view)	Author: Georg Brandl (georg.brandl) *	Date: 2005-11-11 08:45
Logged In: YES user_id=1188172 Ping!
msg26205 - (view)	Author: Martin v. Löwis (loewis) *	Date: 2005-11-13 10:31
Logged In: YES user_id=21627 The patch looks wrong: for 'I' (capital i), you va_arg unsigned long; I think 'I' should do unsigned int instead. A minor nit: why does it move the 'l' case (lower L)? Apart from that, the patch looks fine.
msg26206 - (view)	Author: Georg Brandl (georg.brandl) *	Date: 2005-11-24 15:39
Logged In: YES user_id=1188172 Corrected patch committed in rev. 41527 and 41528 (2.4).