Regression in Error conversion from Infallible #66757
Description
The following code:
use std::convert::{TryFrom, Infallible}; struct E; impl From<Infallible> for E { fn from(_: Infallible) -> E { E } } fn foo() -> Result<(), E> { u32::try_from(1u32)?; Ok(()) }compiles on stable but fails to compile on nightly with:
error[E0277]: `?` couldn't convert the error to `E` --> src/lib.rs:13:24 | 13 | u32::try_from(1u32)?; | ^ the trait `std::convert::From<()>` is not implemented for `E` | = note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait = help: the following implementations were found: <E as std::convert::From<!>> = note: required by `std::convert::From::from` This was discovered through bytecodealliance/wasmtime#633