Confusing error message when feature generic_const_exprs is used. #100414
Description
Given the following code: https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=5c971999babd48f6d0b57e56450996f2
#![feature(generic_const_exprs)] trait True {} struct Is<const V: bool>; impl True for Is<true> {} fn g<T>() where Is<{ std::mem::size_of::<T>() == 0 }>: True { } fn main() { g::<usize>(); }The current output is:
error[[E0308]](https://doc.rust-lang.org/nightly/error-index.html#E0308): mismatched types --> src/main.rs:14:5 | 14 | g::<usize>(); | ^^^^^^^^^^ expected `false`, found `true` | = note: expected type `false` found type `true` For more information about this error, try `rustc --explain E0308`. Due to something true and false are considered types, not values, also the error span is not any informative.