rust/clippy_lints
bors e8703a0ce2 Auto merge of #10098 - lukaslueg:size_of_ref, r=Jarcho
Add size_of_ref lint

This addresses #9995, which is likely raising a valid point about `std::mem::size_of_val()`: It's [very easy to use double-references as the argument](https://github.com/apache/arrow-datafusion/pull/4371#discussion_r1032385224), which the function will happily accept and give back the size of _the reference_, not the size of the value _behind_ the reference. In the worst case, if the value matches the programmer's expectation, this seems to work, while in fact, everything will go horribly wrong e.g. on a different platform.

The size of a `&T` is independent of what `T` is, and people might want to use `std::mem::size_of_val()` to actually get the size of _any_ reference (e.g. via `&&()`). I would rather suggest that this is always bad behavior, though ([instead](https://doc.rust-lang.org/reference/type-layout.html#pointers-and-references-layout), [and](https://doc.rust-lang.org/stable/std/primitive.usize.html#associatedconstant.BITS)). I, therefore, put this lint into `correctness`.

Since the problem is usually easily fixed by removing extra `&`, I went light on suggesting code.

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changelog: New lint: [`size_of_ref`]
[#10098](https://github.com/rust-lang/rust-clippy/pull/10098)
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2022-12-24 23:33:13 +00:00
..
src Auto merge of #10098 - lukaslueg:size_of_ref, r=Jarcho 2022-12-24 23:33:13 +00:00
Cargo.toml Bump Clippy version -> 0.1.68 2022-12-17 13:57:41 +01:00
README.md

This crate contains Clippy lints. For the main crate, check GitHub.