[issue39001] possible problem with 64-bit mingw DECREF

[Dave Lawrence]

New submission from Dave Lawrence <mail.dave.lawrence at gmail.com>:

I am calling a python method from C using the attached code.

The Site.py file is:

import os

def find_site():
    path = os.path.abspath(".")
    return path

Cross compiled to Windows from Linux using mxe.cc and python 2.7.17
On 32-bit this runs as expected:

module = 028BC710
result = 0283D6B0
Found Site at \\wsl$\Ubuntu\home\dl
result = 0283D6B0 decref
module = 028BC710 decref

Site = \\wsl$\Ubuntu\home\dl
but crashes on 64-bit, failing to DECREF result:

module = 0000000002750408
result = 0000000000E62EF0
Found Site at \\wsl$\Ubuntu\home\dl
result = 0000000000E62EF0 decref

In both cases the libpython was made using the .dll copied from the target Windows machine and pexports and dlltool to create the .a

 if the return value of the python is return "C:/Test/Path" it works. if you add test2 = test and return test2 it fails. if you say test2 = "".join(c for c in path) and return test2 it fails. if you set path2 = "C:/Test/Path and return test2 it works

using Py_REFCNT [in the C code] shows a value of 2 for a return "c:/test" but a value of 1 a return test

----------
components: Library (Lib), Windows
files: py.cc
messages: 358033
nosy: Dave Lawrence, paul.moore, steve.dower, tim.golden, zach.ware
priority: normal
severity: normal
status: open
title: possible problem with 64-bit mingw DECREF
type: crash
versions: Python 2.7
Added file: https://bugs.python.org/file48767/py.cc

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue39001>
_______________________________________