Define custom copy/move constructors/operators for SharedData and GlobalEvent #493
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GlobalEvent
- This fixes a segfault that can occur after a SharedData is copied
klingaard
reviewed
Apr 23, 2024
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With the exception of the move constructor, can these not be = default?
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No, we have to explicitly initialize ev_handler_lifetime_ to point to the ev_handler_ inside the new instance in all of these cases. Otherwise, it will point to rhs.ev_handler_.
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Ah, I see the difference. Thanks!
klingaard
reviewed
Apr 23, 2024
| @@ -65,6 +70,44 @@ namespace sparta | |||
| writePS(std::forward<U>(init_val)); | |||
| } | |||
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| SharedData(const SharedData& rhs) : | |||
| ev_update_(rhs.ev_update_), | |||
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Why copy the ev_update_ if it's going to be reset?
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We still need the other fields inside ev_update_ to get copied.
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Good catch. This has been plaguing me for quite some time! |
klingaard
approved these changes
Apr 24, 2024
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I ran into a segfault when I tried to create an
std::vectorofSharedData. There were two underlying causes for this:GlobalEventis moved/copied, it doesn't updateev_handler_lifetime_to point to the new instance ofevent_handler_. If the originalGlobalEventwas later destroyed, the copy would segfault when it tried to fire its handler.SharedDatais moved/copied, itsev_update_receives a copy of the handler in the originalSharedData. If the original was later destroyed, the copy would segfault when it tried to perform its state update.This PR defines copy/move constructors and assignment operators for both classes so that everything gets updated properly and the copies can continue to function after the originals are destroyed.