Fix UB from incorrect Vec::set_len usage #121
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The clippy::uninit_vec lint caught this issue, which I discovered while cleaning those warnings up. This introduces buffer zeroing in several places, which will have a performance impact. In order to safely avoid this zeroing, we will need to support `&mut [MaybeUninit<u8>]` as an output buffer.
jschwe
reviewed
Jul 9, 2025
|
force pushed to rephrase two of my safety comments. |
The MaybeUninit::write method was only stabilized in Rust 1.55.
This was referenced Aug 3, 2025
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The clippy::uninit_vec lint pointed out this issue in a few places, and then some manual review found many more places where Vec::set_len was being abused.
This introduces buffer zeroing in several places, which will have a performance impact. In order to safely avoid this zeroing, we will need to support
&mut [MaybeUninit<u8>]as an output buffer.For more information, see the clippy lint's documentation: https://rust-lang.github.io/rust-clippy/master/index.html#uninit_vec