fixed Python derived types crashing on shutdown of Python process

lostmsu · lostmsu · commit fd451d5dd910 · 2021-12-20T15:20:48.000-08:00
clearing GCHandle from an instance of Python derived type would drop the last reference to it, so it was destroyed without being removed from reflectedObjects collection
diff --git a/src/runtime/extensiontype.cs b/src/runtime/extensiontype.cs
@@ -80,16 +80,17 @@ public unsafe static void tp_dealloc(NewReference lastRef)
 
             tp_clear(lastRef.Borrow());
 
-            bool deleted = loadedExtensions.Remove(lastRef.DangerousGetAddress());
-            Debug.Assert(deleted);
-
             // we must decref our type: https://docs.python.org/3/c-api/typeobj.html#c.PyTypeObject.tp_dealloc
             DecrefTypeAndFree(lastRef.Steal());
         }
 
         public static int tp_clear(BorrowedReference ob)
         {
-            TryFreeGCHandle(ob);
+            if (TryFreeGCHandle(ob))
+            {
+                bool deleted = loadedExtensions.Remove(ob.DangerousGetAddress());
+                Debug.Assert(deleted);
+            }
 
             int res = ClassBase.BaseUnmanagedClear(ob);
             return res;
diff --git a/src/runtime/runtime.cs b/src/runtime/runtime.cs
@@ -339,6 +339,7 @@ static bool TryCollectingGarbage(int runs, bool forceBreakLoops)
                 else if (forceBreakLoops)
                 {
                     NullGCHandles(CLRObject.reflectedObjects);
+                    CLRObject.reflectedObjects.Clear();
                 }
             }
             return false;

Original file line number	Diff line number	Diff line change
`@@ -339,6 +339,7 @@ static bool TryCollectingGarbage(int runs, bool forceBreakLoops)`
`339`	`339`	`else if (forceBreakLoops)`
`340`	`340`	`{`
`341`	`341`	`NullGCHandles(CLRObject.reflectedObjects);`
	`342`	`+ CLRObject.reflectedObjects.Clear();`
`342`	`343`	`}`
`343`	`344`	`}`
`344`	`345`	`return false;`