New submission from STINNER Victor <vstin...@redhat.com>:
test_io leaks references on AMD64 Fedora Rawhide Refleaks 3.8: https://buildbot.python.org/all/#/builders/229/builds/10 test_io leaked [23208, 23204, 23208] references, sum=69620 test_io leaked [7657, 7655, 7657] memory blocks, sum=22969 The issue has been introduced by my change: commit c15a682603a47f5aef5025f6a2e3babb699273d6 Author: Victor Stinner <vstin...@redhat.com> Date: Thu Jun 13 00:23:49 2019 +0200 bpo-37223: test_io: silence destructor errors (GH-14031) * bpo-18748: Fix _pyio.IOBase destructor (closed case) (GH-13952) _pyio.IOBase destructor now does nothing if getting the closed attribute fails to better mimick _io.IOBase finalizer. (cherry picked from commit 4f6f7c5a611905fb6b81671547f268c226bc646a) * bpo-37223: test_io: silence destructor errors (GH-13954) Implement also MockNonBlockWriterIO.seek() method. (cherry picked from commit b589cef9c4dada2fb84ce0fae5040ecf16d9d5ef) * bpo-37223, test_io: silence last 'Exception ignored in:' (GH-14029) Use catch_unraisable_exception() to ignore 'Exception ignored in:' error when the internal BufferedWriter of the BufferedRWPair is destroyed. The C implementation doesn't give access to the internal BufferedWriter, so just ignore the warning instead. (cherry picked from commit 913fa1c8245d1cde6edb4254f4fb965cc91786ef) It seems like the root issue is the usage of catch_unraisable_exception() in test_io. class catch_unraisable_exception: def __init__(self): self.unraisable = None self._old_hook = None def _hook(self, unraisable): self.unraisable = unraisable def __enter__(self): self._old_hook = sys.unraisablehook sys.unraisablehook = self._hook return self def __exit__(self, *exc_info): # Clear the unraisable exception to explicitly break a reference cycle del self.unraisable sys.unraisablehook = self._old_hook *Sometimes* "del self.unraisable" of __exit__() triggers a new unraisable exception which calls again the _hook() method which sets again the unraisable attribute. catch_unraisable_exception resurects _io.BufferedWriter objects, and then "del self.unraisable" calls again their finalizer: iobase_finalize() is called again, and iobase_finalize() calls PyErr_WriteUnraisable() on close() failure. ---------- messages: 345449 nosy: vstinner priority: normal severity: normal status: open title: test_io leaks references on AMD64 Fedora Rawhide Refleaks 3.8 versions: Python 3.8 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue37261> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
