diff options
Diffstat (limited to 'compiler/rustc_trait_selection/src/solve/normalize.rs')
| -rw-r--r-- | compiler/rustc_trait_selection/src/solve/normalize.rs | 104 |
1 files changed, 76 insertions, 28 deletions
diff --git a/compiler/rustc_trait_selection/src/solve/normalize.rs b/compiler/rustc_trait_selection/src/solve/normalize.rs index 79fb044a67f..5f1e63ab225 100644 --- a/compiler/rustc_trait_selection/src/solve/normalize.rs +++ b/compiler/rustc_trait_selection/src/solve/normalize.rs @@ -1,10 +1,10 @@ use std::assert_matches::assert_matches; use std::fmt::Debug; -use std::marker::PhantomData; use rustc_data_structures::stack::ensure_sufficient_stack; use rustc_infer::infer::InferCtxt; use rustc_infer::infer::at::At; +use rustc_infer::traits::solve::Goal; use rustc_infer::traits::{FromSolverError, Obligation, TraitEngine}; use rustc_middle::traits::ObligationCause; use rustc_middle::ty::{ @@ -45,11 +45,37 @@ where T: TypeFoldable<TyCtxt<'tcx>>, E: FromSolverError<'tcx, NextSolverError<'tcx>>, { + let (value, goals) = + deeply_normalize_with_skipped_universes_and_ambiguous_goals(at, value, universes)?; + assert_eq!(goals, vec![]); + + Ok(value) +} + +/// Deeply normalize all aliases in `value`. This does not handle inference and expects +/// its input to be already fully resolved. +/// +/// Additionally takes a list of universes which represents the binders which have been +/// entered before passing `value` to the function. This is currently needed for +/// `normalize_erasing_regions`, which skips binders as it walks through a type. +/// +/// This returns a set of stalled obligations if the typing mode of the underlying infcx +/// has any stalled coroutine def ids. +pub fn deeply_normalize_with_skipped_universes_and_ambiguous_goals<'tcx, T, E>( + at: At<'_, 'tcx>, + value: T, + universes: Vec<Option<UniverseIndex>>, +) -> Result<(T, Vec<Goal<'tcx, ty::Predicate<'tcx>>>), Vec<E>> +where + T: TypeFoldable<TyCtxt<'tcx>>, + E: FromSolverError<'tcx, NextSolverError<'tcx>>, +{ let fulfill_cx = FulfillmentCtxt::new(at.infcx); let mut folder = - NormalizationFolder { at, fulfill_cx, depth: 0, universes, _errors: PhantomData }; - - value.try_fold_with(&mut folder) + NormalizationFolder { at, fulfill_cx, depth: 0, universes, stalled_goals: vec![] }; + let value = value.try_fold_with(&mut folder)?; + let errors = folder.fulfill_cx.select_all_or_error(at.infcx); + if errors.is_empty() { Ok((value, folder.stalled_goals)) } else { Err(errors) } } struct NormalizationFolder<'me, 'tcx, E> { @@ -57,7 +83,7 @@ struct NormalizationFolder<'me, 'tcx, E> { fulfill_cx: FulfillmentCtxt<'tcx, E>, depth: usize, universes: Vec<Option<UniverseIndex>>, - _errors: PhantomData<E>, + stalled_goals: Vec<Goal<'tcx, ty::Predicate<'tcx>>>, } impl<'tcx, E> NormalizationFolder<'_, 'tcx, E> @@ -98,10 +124,7 @@ where ); self.fulfill_cx.register_predicate_obligation(infcx, obligation); - let errors = self.fulfill_cx.select_all_or_error(infcx); - if !errors.is_empty() { - return Err(errors); - } + self.select_all_and_stall_coroutine_predicates()?; // Alias is guaranteed to be fully structurally resolved, // so we can super fold here. @@ -139,7 +162,7 @@ where let result = if infcx.predicate_may_hold(&obligation) { self.fulfill_cx.register_predicate_obligation(infcx, obligation); - let errors = self.fulfill_cx.select_all_or_error(infcx); + let errors = self.fulfill_cx.select_where_possible(infcx); if !errors.is_empty() { return Err(errors); } @@ -152,6 +175,27 @@ where self.depth -= 1; Ok(result) } + + fn select_all_and_stall_coroutine_predicates(&mut self) -> Result<(), Vec<E>> { + let errors = self.fulfill_cx.select_where_possible(self.at.infcx); + if !errors.is_empty() { + return Err(errors); + } + + self.stalled_goals.extend( + self.fulfill_cx + .drain_stalled_obligations_for_coroutines(self.at.infcx) + .into_iter() + .map(|obl| obl.as_goal()), + ); + + let errors = self.fulfill_cx.collect_remaining_errors(self.at.infcx); + if !errors.is_empty() { + return Err(errors); + } + + Ok(()) + } } impl<'tcx, E> FallibleTypeFolder<TyCtxt<'tcx>> for NormalizationFolder<'_, 'tcx, E> @@ -254,27 +298,31 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for DeeplyNormalizeForDiagnosticsFolder<'_, fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> { let infcx = self.at.infcx; - infcx - .commit_if_ok(|_| { - deeply_normalize_with_skipped_universes( - self.at, - ty, - vec![None; ty.outer_exclusive_binder().as_usize()], - ) - }) - .unwrap_or_else(|_: Vec<ScrubbedTraitError<'tcx>>| ty.super_fold_with(self)) + let result = + infcx.commit_if_ok(|_| { + deeply_normalize_with_skipped_universes_and_ambiguous_goals::< + _, + ScrubbedTraitError<'tcx>, + >(self.at, ty, vec![None; ty.outer_exclusive_binder().as_usize()]) + }); + match result { + Ok((ty, _)) => ty, + Err(_) => ty.super_fold_with(self), + } } fn fold_const(&mut self, ct: ty::Const<'tcx>) -> ty::Const<'tcx> { let infcx = self.at.infcx; - infcx - .commit_if_ok(|_| { - deeply_normalize_with_skipped_universes( - self.at, - ct, - vec![None; ct.outer_exclusive_binder().as_usize()], - ) - }) - .unwrap_or_else(|_: Vec<ScrubbedTraitError<'tcx>>| ct.super_fold_with(self)) + let result = + infcx.commit_if_ok(|_| { + deeply_normalize_with_skipped_universes_and_ambiguous_goals::< + _, + ScrubbedTraitError<'tcx>, + >(self.at, ct, vec![None; ct.outer_exclusive_binder().as_usize()]) + }); + match result { + Ok((ct, _)) => ct, + Err(_) => ct.super_fold_with(self), + } } } |