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@ -19,11 +19,11 @@ boggling.
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* Transmute has an overloaded return type. If you do not specify the return type
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it may produce a surprising type to satisfy inference.
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* Transmuting an `&` to `&mut` is UB. While certain usages may *appear* safe,
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note that the Rust optimizer is free to assume that a shared reference won't
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change through its lifetime and thus such transmutation will run afoul of those
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assumptions. So:
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* Transmuting an `&` to `&mut` is *always* UB.
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* Transmuting an `&` to `&mut` is Undefined Behavior. While certain usages may
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*appear* safe, note that the Rust optimizer is free to assume that a shared
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reference won't change through its lifetime and thus such transmutation will
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run afoul of those assumptions. So:
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* Transmuting an `&` to `&mut` is *always* Undefined Behavior.
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* No you can't do it.
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* No you're not special.
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@ -32,8 +32,8 @@ boggling.
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* When transmuting between different compound types, you have to make sure they
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are laid out the same way! If layouts differ, the wrong fields are going to
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get filled with the wrong data, which will make you unhappy and can also be UB
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(see above).
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get filled with the wrong data, which will make you unhappy and can also be
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Undefined Behavior (see above).
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So how do you know if the layouts are the same? For `repr(C)` types and
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`repr(transparent)` types, layout is precisely defined. But for your
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