Allow value parameters to be passed by copy instead of consuming #766
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adetaylor
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Prior to this point, a value parameter of a C++ function consumed a UniquePtr<T>. With this change, a value parameter is now of type impl ValueParam<T> which can be either a UniquePtr<T> (avoiding any compatibility break) or a &T or various other things.
These are failing on Windows only for unknown reasons and will be investigated in #819.
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adetaylor
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bsilver8192
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Feb 28, 2022
| if this.param.needs_stack_space() { | ||
| this.space = Some(MaybeUninit::uninit()); | ||
| this.param | ||
| .populate_stack_space(Pin::new_unchecked(this.space.as_mut().unwrap())); |
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What prevents this Rust object (which is the storage for a C++ object) from being memcpyed to a different address? Some of the tests fail for me after this PR, I think because of this.
With some additional prints, it looks like the drop for ValueParamHandler is definitely being called with a different address.
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Hmm, thanks, I will revert or fix this tomorrow.
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Part of #379.