Make NonSendMarker !Send#19107
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alice-i-cecile merged 1 commit intobevyengine:mainfrom May 7, 2025
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I'm very much hoping to remove this for 0.17 but we might as well merge this.
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# Objective In bevyengine#18301, `NonSendMarker` was defined in such a way that it actually implements `Send`. This isn't strictly a soundness issue, as its goal is to be used as a `SystemParam`, and it _does_ appropriately mark system access as `!Send`. It just seems odd that `NonSendMarker: Send`. ## Solution - Made `NonSendMarker` wrap `PhantomData<*mut ()>`, which forces it to be `!Send`. ## Testing - CI --- ## Notes This does mean constructing a `NonSendMarker` _value_ will require using the `SystemParam` trait, but I think that's acceptable as the marker as a value should be rarely required if at all.
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Objective
In #18301,
NonSendMarkerwas defined in such a way that it actually implementsSend. This isn't strictly a soundness issue, as its goal is to be used as aSystemParam, and it does appropriately mark system access as!Send. It just seems odd thatNonSendMarker: Send.Solution
NonSendMarkerwrapPhantomData<*mut ()>, which forces it to be!Send.Testing
Notes
This does mean constructing a
NonSendMarkervalue will require using theSystemParamtrait, but I think that's acceptable as the marker as a value should be rarely required if at all.