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Wrong type suggested in overflowing_bin_hex #135404

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@s-cerevisiae

Description

Code

fn main() {
    _ = 0x8FFF_FFFF_FFFF_FFFEu32;
}

Current output

error: literal out of range for `i32`
 --> src/main.rs:2:9
  |
2 |     _ = 0x8FFF_FFFF_FFFF_FFFE;
  |         ^^^^^^^^^^^^^^^^^^^^^
  |
  = note: the literal `0x8FFF_FFFF_FFFF_FFFE` (decimal `10376293541461622782`) does not fit into the type `i32` and will become `-2i32`
  = help: consider using the type `i128` instead
  = note: `#[deny(overflowing_literals)]` on by default
help: to use as a negative number (decimal `-2`), consider using the type `u32` for the literal and cast it to `i32`
  |
2 |     _ = 0x8FFF_FFFF_FFFF_FFFEu32 as i32;
  |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Desired output

error: literal out of range for `i32`
 --> src/main.rs:2:9
  |
2 |     _ = 0x8FFF_FFFF_FFFF_FFFE;
  |         ^^^^^^^^^^^^^^^^^^^^^
  |
  = note: the literal `0x8FFF_FFFF_FFFF_FFFE` (decimal `10376293541461622782`) does not fit into the type `i32` and will become `-2i32`
  = help: consider using the type `i128` instead
  = note: `#[deny(overflowing_literals)]` on by default
help: to use as a negative number (decimal `-2`), consider using the type `u64` for the literal and cast it to `i32`
  |
2 |     _ = 0x8FFF_FFFF_FFFF_FFFEu64 as i32;
  |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Rationale and extra context

Found this when working on #135249. Wrong type is suggested in overflowing bin/hex literals for them to be casted back to current type.

Other cases

Rust Version

rustc 1.84.0 (9fc6b4312 2025-01-07)
binary: rustc
commit-hash: 9fc6b43126469e3858e2fe86cafb4f0fd5068869
commit-date: 2025-01-07
host: x86_64-unknown-linux-gnu
release: 1.84.0
LLVM version: 19.1.5

Anything else?

No response

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