Fixed crash in finalizer of CLR types defined in Python, that survive engine shutdown #1260
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Interesting. It appears, that the fix is legitimate, but the test for it causes segfault in soft shutdown mode with xplat. Which probably means it is caused by a separate issue :/ |
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Coverage 86.25% 86.25%
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Files 1 1
Lines 291 291
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Hits 251 251
Misses 40 40
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@amos402 I could see it being freed by one of |
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pythonnet/src/runtime/classderived.cs Lines 77 to 80 in 927f980 It set by a weak GCHandle instead after it freed. |
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… engine shutdown pythonnet#1256 pythonnet#1256 During engine shutdown all links from Python to .NET instances are severed. If an instance of CLR class defined in Python survives the shutdown (for example, a reference is stored in static field) and later gets finalized, it will attempt to severe link again, which is an invalid operation. The fix is to check if the link has already been severed and skip that step during finalization.
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Dec 18, 2020
… engine shutdown (pythonnet#1260) pythonnet#1256 pythonnet#1256 During engine shutdown all links from Python to .NET instances are severed. If an instance of CLR class defined in Python survives the shutdown (for example, a reference is stored in static field) and later gets finalized, it will attempt to severe link again, which is an invalid operation. The fix is to check if the link has already been severed and skip that step during finalization.
BadSingleton
pushed a commit
to Unity-Technologies/pythonnet
that referenced
this pull request
Dec 18, 2020
… engine shutdown (pythonnet#1260) pythonnet#1256 pythonnet#1256 During engine shutdown all links from Python to .NET instances are severed. If an instance of CLR class defined in Python survives the shutdown (for example, a reference is stored in static field) and later gets finalized, it will attempt to severe link again, which is an invalid operation. The fix is to check if the link has already been severed and skip that step during finalization.
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What does this implement/fix? Explain your changes.
During engine shutdown all links from Python to .NET instances are severed. If an instance of CLR class defined in Python survives the shutdown (for example, a reference is stored in static field) and later gets finalized, it will attempt to severe link again, which is an invalid operation.
The fix is to check if the link has already been severed and skip that step during finalization.
Additionally in this change: refactored
MoveClrInstancesOnwershipToPythonDoes this close any currently open issues?
#1256
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