Fix reference/memory leaks in decode_definite_long_string#290
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agronholm merged 2 commits intoagronholm:masterfrom Mar 21, 2026
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Two reference/memory leaks in the C extension's long string decoder: 1. Missing Py_DECREF(ret) before reassignment after PyUnicode_Concat, leaking all intermediate Unicode objects during chunked decoding. 2. Missing PyMem_Free(buffer) on the success path, leaking the scratch buffer used for UTF-8 boundary handling.
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Fix two reference/memory leaks in the C extension's long string decoder.
Changes
Missing
Py_DECREF(ret)before reassignment afterPyUnicode_Concat, leaking all intermediate Unicode objects during chunked decoding (decode_definite_long_string).Missing
PyMem_Free(buffer)on the success path, potentially leaking the scratch buffer used for UTF-8 boundary handling (decode_definite_long_string).Checklist
If this is a user-facing code change, like a bugfix or a new feature, please ensure that
you've fulfilled the following conditions (where applicable):
tests/) which would fail without your patchtests, but added applicable input withinscripts/ref_leak_test.pyand tested before and after changes:docs/), in case of behavior changes or newfeatures
docs/versionhistory.rst).If this is a trivial change, like a typo fix or a code reformatting, then you can ignore
these instructions.
Updating the changelog
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**UNRELEASED**as the version.If, say, your patch fixes issue #123, the entry should look like this:
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