lint suggestion: `suspicious_mixed_type_operation`

What it does

Bit-related functions return u32 , this allows to compile some "suspicious" operations from mismatching calling types. which can leads to overflows like:

let x = u8::BITS - 5u64.leading_zeros();

let x: u16 = 0b1111111111111111;
let _ = u8::BITS - x.trailing_ones();

let mask = 1u32 << 5u64.leading_zeros();

Advantage

• Avoids overflows
• In the cases where it does not overflow, Improves readability

Drawbacks

The lint should be black list specific cases, which are clearly misleading. Otherwise, if the cases are kept to general there is the risk of triggering for false positives / true negatives.

Example

let x = u8::BITS - 5u64.leading_zeros();

let x: u16 = 0b1111111111111111;
let _ = u8::BITS - x.trailing_ones();

let mask = 1u32 << 5u64.leading_zeros();

Could be written as:

let x = u8::BITS - 5u8.leading_zeros();

let x: u16 = 0b1111111111111111;
let _ = u16::BITS - x.trailing_ones();

let mask = 1u32 << 5u32.leading_zeros();

Comparison with existing lints

No response

Additional Context

This lint was inspired with the conversation on: https://github.com/rust-lang/rust-clippy/pull/16902#discussion_r3412438731

Start by reading the linked rust-lang/rust-clippy pull request discussion and reviewing the mixed-type examples in this issue. Define which suspicious operations the lint should blacklist while avoiding false positives, compare the proposal with existing lints, and consider the work complete when that scope is agreed and the examples are covered.