[caelyreth]

Fixes #164144

about this bug

raw_borrows_via_references rewrites &mut x as *mut usize to &raw mut x.

When x is [usize; 2], that drops the cast, so p becomes *mut [usize; 2] and the fixed code does not compile.

A cast that only changes mutability, &mut x as *const i32, is dropped the same way.

after this fix

• Remove as *const T only when &raw already has that type.
• Otherwise suggest &raw mut x as *mut usize.
• A redundant cast such as &(*x).0 as *const i32 is still removed.

llm disclosure

The LLM (specifically, Grok 4.7) was used for improving the ui test case edge case coverage only.

[rustbot]

r? @davidtwco

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