unnecessary_cast fix suggestion introduces compile error for (expr_with_float_literals as f64).powf(2.0) #14366
Description
Summary
The following code triggers the lint:
((1.0 / 8.0) as f64).powf(i as f64)
^^^^^^^^^^^^^^^^^^^^ help: try: `(1.0 / 8.0)`
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= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_cast
= note: `-D clippy::unnecessary-cast` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::unnecessary_cast)]`
The problem is that when the code is "fixed" according to the suggestion ((1.0 / 8.0).powf(i as f64)), the rust compiler gives the following error
can't call method `powf` on ambiguous numeric type `{float}`
so it's not really an unnecessary cast, since the compiler needs the type information for powf. I can work around it by doing 1.0f64 / 8.0f64 to avoid needing to cast while still having sufficient information to allow powf to disambiguate
Reproducer
No response
Version
rustc 1.85.0 (4d91de4e4 2025-02-17)
binary: rustc
commit-hash: 4d91de4e48198da2e33413efdcd9cd2cc0c46688
commit-date: 2025-02-17
host: x86_64-apple-darwin
release: 1.85.0
LLVM version: 19.1.7
Additional Labels
No response