29 lines
848 B
Plaintext
29 lines
848 B
Plaintext
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== Why is this an issue?
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Transmuting between collections of different types can lead to undefined behavior due to differences in ABI, size, or alignment. This can result in serious issues like out-of-bounds memory access.
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=== Code examples
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==== Noncompliant code example
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[source,rust,diff-id=1,diff-type=noncompliant]
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----
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let vec = vec![2_u16];
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unsafe {
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std::mem::transmute::<_, Vec<u32>>(vec); // Noncompliant: Different size, likely out-of-bounds memory access.
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}
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----
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==== Compliant solution
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[source,rust,diff-id=1,diff-type=compliant]
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----
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let vec = vec![2_u16];
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let vec_u32: Vec<u32> = vec.into_iter().map(u32::from).collect(); // Compliant: Iterates, maps, and collects the values safely.
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----
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== Resources
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=== Documentation
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* Clippy Lints - https://rust-lang.github.io/rust-clippy/master/index.html#unsound_collection_transmute
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