Sometimes, Calling ExecuteIfBound failed because of UObject’s RF_Unreachable flag in GarbageCollecting Process.
If Other thread called Delegate’s ExecuteIfBound function Between Set and Clear RF_Unreachable, TBaseUObjectMethodDelegateInstance’s
FORCEINLINE const void* GetRawUserObjectInternal( ) const
{
return UserObject.Get();
}
function returned NULL. (UserObject is WeakObjectPtr, so if RF_Unreachable, return NULL)
If BindUObject is used, UObject binded Delegate need to be RF_RootSet?
Because it’s only a weak pointer, if the object is not RF_RootSet, there’s also the possibility that the object will be garbage collected (deleted!) in the middle of your delegate callback! I would recommend not running any code that interacts with UObjects during GC.
UObjects aren’t really safe to use from any thread other than the main thread.
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