[New-bugs-announce] [issue42887] Multiple assignments of attribute "__sizeof__" will cause a segfault

[Xinmeng Xia]

New submission from Xinmeng Xia <xiaxm at smail.nju.edu.cn>:

In the following program 1， method  "__sizeof__()" is called and assigned multiple times. The program can work well on Python 3.10. However if I change "__sizeof__()" to  "__sizeof__".  Then a segmentation fault is reported. I think something wrong for the parser when dealing build-in attribute assignment.



program 1: 
=========================
mystr  = "hello123"
for x in range(1000000):
    mystr = mystr.__sizeof__()
    print(mystr)
=========================
56
28
28
.......
28
28

Output: work well as expected.


program 2: 
==========================
mystr = "hello123"
for x in range(1000000):
        mystr = mystr.__sizeof__
        print(mystr)
==========================
<built-in method __sizeof__ of builtin_function_or_method object at 0x7f04d3e0c220>
......
<built-in method __sizeof__ of builtin_function_or_method object at 0x7f04d3e0c4f0>
<built-in method __sizeof__ of builtin_function_or_method object at 0x7f04d3e0c540>
Segmentation fault (core dumped)

Expected output: no segfault.

----------
components: Interpreter Core
messages: 384797
nosy: xxm
priority: normal
severity: normal
status: open
title: Multiple assignments of attribute "__sizeof__" will cause a segfault
type: crash
versions: Python 3.10

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue42887>
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