bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

remove unnecessary sized checks

Browse source
This commit is contained in:
Lukas Markeffsky 2024-03-13 23:35:24 +01:00
parent 8ad94111ad
commit 8fe99f57a4
4 changed files with 15 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

2
compiler/rustc_trait_selection/src/solve/assembly/mod.rs
View file

@ -128,7 +128,7 @@ pub(super) trait GoalKind<'tcx>:
goal: Goal<'tcx, Self>,
) -> QueryResult<'tcx>;
/// A type is `Copy` or `Clone` if its components are `Sized`.
/// A type is `Sized` if its tail component is `Sized`.
///
/// These components are given by built-in rules from
/// [`structural_traits::instantiate_constituent_tys_for_sized_trait`].

5
compiler/rustc_trait_selection/src/solve/assembly/structural_traits.rs
View file

@ -154,8 +154,9 @@ pub(in crate::solve) fn instantiate_constituent_tys_for_sized_trait<'tcx>(
bug!("unexpected type `{ty}`")
}
// impl Sized for (T1, T2, .., Tn) where T1: Sized, T2: Sized, .. Tn: Sized
ty::Tuple(tys) => Ok(tys.iter().map(ty::Binder::dummy).collect()),
// impl Sized for ()
// impl Sized for (T1, T2, .., Tn) where Tn: Sized if n >= 1
ty::Tuple(tys) => Ok(tys.last().map_or_else(Vec::new, |&ty| vec![ty::Binder::dummy(ty)])),
// impl Sized for Adt<Args...> where sized_constraint(Adt)<Args...>: Sized
// `sized_constraint(Adt)` is the deepest struct trail that can be determined