python / python/cpython

test_initconfig_get_api fails on platforms where malloc(0) returns NULL

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tests type-bug
Dominant language
Python
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Description

Bug report

Bug description:

test_initconfig_get_api (Programs/_testembed.c) executes the code

    assert(PyInitConfig_GetStrList(config, "xoptions", &length, &items) == 0);
    assert(length == 0);

PyInitConfig_GetStrList has malloc

*items = malloc(list->length * sizeof(char*));

if length is zero the behavior of malloc(0) is implementation defined, this seems to be problematic on platforms where malloc of zero returns NULL.

CPython versions tested on:

3.14

Operating systems tested on:

Other

Linked PRs
  • gh-153816

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Research direction

Start with test_initconfig_get_api in Programs/_testembed.c and trace the PyInitConfig_GetStrList call for the zero-length xoptions list. Check the implementation's allocation behavior on platforms where malloc(0) returns NULL, then run the targeted test to confirm it passes without changing the expected length of zero.

Written by the indexing model from the issue text.

Assessment

Tech stack
c, python
Domain
api, testing-qa
Issue type
Bug
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
30/100

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