diff options
Diffstat (limited to 'compiler/rustc_middle/src/ty/sty.rs')
| -rw-r--r-- | compiler/rustc_middle/src/ty/sty.rs | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/compiler/rustc_middle/src/ty/sty.rs b/compiler/rustc_middle/src/ty/sty.rs index cbf545c01c5..58829f72a72 100644 --- a/compiler/rustc_middle/src/ty/sty.rs +++ b/compiler/rustc_middle/src/ty/sty.rs @@ -15,6 +15,7 @@ use rustc_hir::def_id::DefId; use rustc_macros::{HashStable, TyDecodable, TyEncodable, TypeFoldable, extension}; use rustc_span::{DUMMY_SP, Span, Symbol, sym}; use rustc_type_ir::TyKind::*; +use rustc_type_ir::solve::SizedTraitKind; use rustc_type_ir::walk::TypeWalker; use rustc_type_ir::{self as ir, BoundVar, CollectAndApply, DynKind, TypeVisitableExt, elaborate}; use tracing::instrument; @@ -1677,7 +1678,7 @@ impl<'tcx> Ty<'tcx> { let Some(pointee_ty) = self.builtin_deref(true) else { bug!("Type {self:?} is not a pointer or reference type") }; - if pointee_ty.is_trivially_sized(tcx) { + if pointee_ty.has_trivial_sizedness(tcx, SizedTraitKind::Sized) { tcx.types.unit } else { match pointee_ty.ptr_metadata_ty_or_tail(tcx, |x| x) { @@ -1778,17 +1779,17 @@ impl<'tcx> Ty<'tcx> { } } - /// Fast path helper for testing if a type is `Sized`. + /// Fast path helper for testing if a type is `Sized` or `MetaSized`. /// - /// Returning true means the type is known to implement `Sized`. Returning `false` means - /// nothing -- could be sized, might not be. + /// Returning true means the type is known to implement the sizedness trait. Returning `false` + /// means nothing -- could be sized, might not be. /// /// Note that we could never rely on the fact that a type such as `[_]` is trivially `!Sized` /// because we could be in a type environment with a bound such as `[_]: Copy`. A function with /// such a bound obviously never can be called, but that doesn't mean it shouldn't typecheck. /// This is why this method doesn't return `Option<bool>`. #[instrument(skip(tcx), level = "debug")] - pub fn is_trivially_sized(self, tcx: TyCtxt<'tcx>) -> bool { + pub fn has_trivial_sizedness(self, tcx: TyCtxt<'tcx>, sizedness: SizedTraitKind) -> bool { match self.kind() { ty::Infer(ty::IntVar(_) | ty::FloatVar(_)) | ty::Uint(_) @@ -1811,13 +1812,20 @@ impl<'tcx> Ty<'tcx> { | ty::Error(_) | ty::Dynamic(_, _, ty::DynStar) => true, - ty::Str | ty::Slice(_) | ty::Dynamic(_, _, ty::Dyn) | ty::Foreign(..) => false, + ty::Str | ty::Slice(_) | ty::Dynamic(_, _, ty::Dyn) => match sizedness { + SizedTraitKind::Sized => false, + SizedTraitKind::MetaSized => true, + }, + + ty::Foreign(..) => match sizedness { + SizedTraitKind::Sized | SizedTraitKind::MetaSized => false, + }, - ty::Tuple(tys) => tys.last().is_none_or(|ty| ty.is_trivially_sized(tcx)), + ty::Tuple(tys) => tys.last().is_none_or(|ty| ty.has_trivial_sizedness(tcx, sizedness)), ty::Adt(def, args) => def - .sized_constraint(tcx) - .is_none_or(|ty| ty.instantiate(tcx, args).is_trivially_sized(tcx)), + .sizedness_constraint(tcx, sizedness) + .is_none_or(|ty| ty.instantiate(tcx, args).has_trivial_sizedness(tcx, sizedness)), ty::Alias(..) | ty::Param(_) | ty::Placeholder(..) | ty::Bound(..) => false, |