diff options
Diffstat (limited to 'compiler/rustc_trait_selection/src')
18 files changed, 241 insertions, 208 deletions
diff --git a/compiler/rustc_trait_selection/src/errors.rs b/compiler/rustc_trait_selection/src/errors.rs index 5e1b80eae39..61793468594 100644 --- a/compiler/rustc_trait_selection/src/errors.rs +++ b/compiler/rustc_trait_selection/src/errors.rs @@ -1,6 +1,6 @@ use rustc_errors::{fluent, ErrorGuaranteed, Handler, IntoDiagnostic}; use rustc_macros::Diagnostic; -use rustc_middle::ty::{PolyTraitRef, Ty, Unevaluated}; +use rustc_middle::ty::{self, PolyTraitRef, Ty}; use rustc_session::Limit; use rustc_span::{Span, Symbol}; @@ -18,7 +18,7 @@ pub struct DumpVTableEntries<'a> { pub struct UnableToConstructConstantValue<'a> { #[primary_span] pub span: Span, - pub unevaluated: Unevaluated<'a>, + pub unevaluated: ty::UnevaluatedConst<'a>, } #[derive(Diagnostic)] diff --git a/compiler/rustc_trait_selection/src/lib.rs b/compiler/rustc_trait_selection/src/lib.rs index d35f74974fd..5d52aa07523 100644 --- a/compiler/rustc_trait_selection/src/lib.rs +++ b/compiler/rustc_trait_selection/src/lib.rs @@ -16,9 +16,7 @@ #![feature(control_flow_enum)] #![feature(drain_filter)] #![feature(hash_drain_filter)] -#![cfg_attr(bootstrap, feature(label_break_value))] #![feature(let_chains)] -#![cfg_attr(bootstrap, feature(let_else))] #![feature(if_let_guard)] #![feature(never_type)] #![feature(type_alias_impl_trait)] diff --git a/compiler/rustc_trait_selection/src/traits/auto_trait.rs b/compiler/rustc_trait_selection/src/traits/auto_trait.rs index bcdfa4f12d3..6ed4f1b8c49 100644 --- a/compiler/rustc_trait_selection/src/traits/auto_trait.rs +++ b/compiler/rustc_trait_selection/src/traits/auto_trait.rs @@ -834,7 +834,7 @@ impl<'tcx> AutoTraitFinder<'tcx> { let reported = tcx.sess.emit_err(UnableToConstructConstantValue { span: tcx.def_span(def_id), - unevaluated: unevaluated.expand(), + unevaluated: unevaluated, }); Err(ErrorHandled::Reported(reported)) } diff --git a/compiler/rustc_trait_selection/src/traits/const_evaluatable.rs b/compiler/rustc_trait_selection/src/traits/const_evaluatable.rs index 5a213987e87..911d1cf8bdf 100644 --- a/compiler/rustc_trait_selection/src/traits/const_evaluatable.rs +++ b/compiler/rustc_trait_selection/src/traits/const_evaluatable.rs @@ -138,7 +138,7 @@ impl<'tcx> ConstUnifyCtxt<'tcx> { #[instrument(skip(tcx), level = "debug")] pub fn try_unify_abstract_consts<'tcx>( tcx: TyCtxt<'tcx>, - (a, b): (ty::Unevaluated<'tcx, ()>, ty::Unevaluated<'tcx, ()>), + (a, b): (ty::UnevaluatedConst<'tcx>, ty::UnevaluatedConst<'tcx>), param_env: ty::ParamEnv<'tcx>, ) -> bool { (|| { @@ -161,7 +161,7 @@ pub fn try_unify_abstract_consts<'tcx>( #[instrument(skip(infcx), level = "debug")] pub fn is_const_evaluatable<'cx, 'tcx>( infcx: &InferCtxt<'cx, 'tcx>, - uv: ty::Unevaluated<'tcx, ()>, + uv: ty::UnevaluatedConst<'tcx>, param_env: ty::ParamEnv<'tcx>, span: Span, ) -> Result<(), NotConstEvaluatable> { @@ -235,14 +235,18 @@ pub fn is_const_evaluatable<'cx, 'tcx>( .emit() } - Err(ErrorHandled::TooGeneric) => Err(if uv.has_infer_types_or_consts() { - NotConstEvaluatable::MentionsInfer - } else if uv.has_param_types_or_consts() { - NotConstEvaluatable::MentionsParam - } else { - let guar = infcx.tcx.sess.delay_span_bug(span, format!("Missing value for constant, but no error reported?")); - NotConstEvaluatable::Error(guar) - }), + Err(ErrorHandled::TooGeneric) => { + let err = if uv.has_non_region_infer() { + NotConstEvaluatable::MentionsInfer + } else if uv.has_non_region_param() { + NotConstEvaluatable::MentionsParam + } else { + let guar = infcx.tcx.sess.delay_span_bug(span, format!("Missing value for constant, but no error reported?")); + NotConstEvaluatable::Error(guar) + }; + + Err(err) + }, Err(ErrorHandled::Linted) => { let reported = infcx.tcx.sess.delay_span_bug(span, "constant in type had error reported as lint"); @@ -250,23 +254,23 @@ pub fn is_const_evaluatable<'cx, 'tcx>( } Err(ErrorHandled::Reported(e)) => Err(NotConstEvaluatable::Error(e)), Ok(_) => { - if uv.substs.has_param_types_or_consts() { - assert!(matches!(infcx.tcx.def_kind(uv.def.did), DefKind::AnonConst)); - let mir_body = infcx.tcx.mir_for_ctfe_opt_const_arg(uv.def); + if uv.substs.has_non_region_param() { + assert!(matches!(infcx.tcx.def_kind(uv.def.did), DefKind::AnonConst)); + let mir_body = infcx.tcx.mir_for_ctfe_opt_const_arg(uv.def); - if mir_body.is_polymorphic { - let Some(local_def_id) = uv.def.did.as_local() else { return Ok(()) }; - tcx.struct_span_lint_hir( - lint::builtin::CONST_EVALUATABLE_UNCHECKED, - tcx.hir().local_def_id_to_hir_id(local_def_id), - span, - |err| { - err.build("cannot use constants which depend on generic parameters in types").emit(); - }) - } - } + if mir_body.is_polymorphic { + let Some(local_def_id) = uv.def.did.as_local() else { return Ok(()) }; + tcx.struct_span_lint_hir( + lint::builtin::CONST_EVALUATABLE_UNCHECKED, + tcx.hir().local_def_id_to_hir_id(local_def_id), + span, + "cannot use constants which depend on generic parameters in types", + |err| err + ) + } + } - Ok(()) + Ok(()) }, } } diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs index d62b399c1b5..6dcf9c4d261 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs @@ -661,7 +661,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> { ); } } - } else if !trait_ref.has_infer_types_or_consts() + } else if !trait_ref.has_non_region_infer() && self.predicate_can_apply(obligation.param_env, trait_ref) { // If a where-clause may be useful, remind the @@ -1898,7 +1898,9 @@ impl<'a, 'tcx> InferCtxtPrivExt<'a, 'tcx> for InferCtxt<'a, 'tcx> { // FIXME(compiler-errors): This could be generalized, both to // be more granular, and probably look past other `#[fundamental]` // types, too. - self.tcx.visibility(def.did()).is_accessible_from(body_id.owner, self.tcx) + self.tcx + .visibility(def.did()) + .is_accessible_from(body_id.owner.def_id, self.tcx) } else { true } @@ -2091,7 +2093,7 @@ impl<'a, 'tcx> InferCtxtPrivExt<'a, 'tcx> for InferCtxt<'a, 'tcx> { // Pick the first substitution that still contains inference variables as the one // we're going to emit an error for. If there are none (see above), fall back to // a more general error. - let subst = data.trait_ref.substs.iter().find(|s| s.has_infer_types_or_consts()); + let subst = data.trait_ref.substs.iter().find(|s| s.has_non_region_infer()); let mut err = if let Some(subst) = subst { self.emit_inference_failure_err(body_id, span, subst, ErrorCode::E0283, true) @@ -2261,13 +2263,22 @@ impl<'a, 'tcx> InferCtxtPrivExt<'a, 'tcx> for InferCtxt<'a, 'tcx> { trait_impls.non_blanket_impls().len() ) }; - + let mut suggestions = vec![( + trait_path_segment.ident.span.shrink_to_lo(), + format!("<{} as ", self.tcx.type_of(impl_def_id)) + )]; + if let Some(generic_arg) = trait_path_segment.args { + let between_span = trait_path_segment.ident.span.between(generic_arg.span_ext); + // get rid of :: between Trait and <type> + // must be '::' between them, otherwise the parser won't accept the code + suggestions.push((between_span, "".to_string(),)); + suggestions.push((generic_arg.span_ext.shrink_to_hi(), format!(">"))); + } else { + suggestions.push((trait_path_segment.ident.span.shrink_to_hi(), format!(">"))); + } err.multipart_suggestion( message, - vec![ - (trait_path_segment.ident.span.shrink_to_lo(), format!("<{} as ", self.tcx.def_path(impl_def_id).to_string_no_crate_verbose())), - (trait_path_segment.ident.span.shrink_to_hi(), format!(">")) - ], + suggestions, Applicability::MaybeIncorrect ); } @@ -2312,7 +2323,7 @@ impl<'a, 'tcx> InferCtxtPrivExt<'a, 'tcx> for InferCtxt<'a, 'tcx> { .substs .iter() .chain(Some(data.term.into_arg())) - .find(|g| g.has_infer_types_or_consts()); + .find(|g| g.has_non_region_infer()); if let Some(subst) = subst { let mut err = self.emit_inference_failure_err( body_id, @@ -2341,7 +2352,7 @@ impl<'a, 'tcx> InferCtxtPrivExt<'a, 'tcx> for InferCtxt<'a, 'tcx> { if predicate.references_error() || self.is_tainted_by_errors() { return; } - let subst = data.substs.iter().find(|g| g.has_infer_types_or_consts()); + let subst = data.substs.iter().find(|g| g.has_non_region_infer()); if let Some(subst) = subst { let err = self.emit_inference_failure_err( body_id, diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs index d90b77fc556..7aae014af60 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs @@ -659,7 +659,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> { _ => {} } - hir_id = self.tcx.hir().local_def_id_to_hir_id(self.tcx.hir().get_parent_item(hir_id)); + hir_id = self.tcx.hir().get_parent_item(hir_id).into(); } } @@ -1231,7 +1231,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> { return; } let trait_pred = self.resolve_vars_if_possible(trait_pred); - if trait_pred.has_infer_types_or_consts() { + if trait_pred.has_non_region_infer() { // Do not ICE while trying to find if a reborrow would succeed on a trait with // unresolved bindings. return; @@ -1425,7 +1425,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> { let mut spans_and_needs_box = vec![]; match liberated_sig.output().kind() { - ty::Dynamic(predicates, _, _) => { + ty::Dynamic(predicates, _, ty::Dyn) => { let cause = ObligationCause::misc(ret_ty.span, fn_hir_id); let param_env = ty::ParamEnv::empty(); @@ -2712,7 +2712,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> { let parent_id = hir.get_parent_item(arg_hir_id); let typeck_results: &TypeckResults<'tcx> = match &in_progress_typeck_results { Some(t) if t.hir_owner == parent_id => t, - _ => self.tcx.typeck(parent_id), + _ => self.tcx.typeck(parent_id.def_id), }; let expr = expr.peel_blocks(); let ty = typeck_results.expr_ty_adjusted_opt(expr).unwrap_or(tcx.ty_error()); diff --git a/compiler/rustc_trait_selection/src/traits/fulfill.rs b/compiler/rustc_trait_selection/src/traits/fulfill.rs index 6f3a9412dde..5802f038e89 100644 --- a/compiler/rustc_trait_selection/src/traits/fulfill.rs +++ b/compiler/rustc_trait_selection/src/traits/fulfill.rs @@ -102,7 +102,7 @@ impl<'a, 'tcx> FulfillmentContext<'tcx> { } /// Attempts to select obligations using `selcx`. - fn select(&mut self, selcx: &mut SelectionContext<'a, 'tcx>) -> Vec<FulfillmentError<'tcx>> { + fn select(&mut self, selcx: SelectionContext<'a, 'tcx>) -> Vec<FulfillmentError<'tcx>> { let span = debug_span!("select", obligation_forest_size = ?self.predicates.len()); let _enter = span.enter(); @@ -197,8 +197,8 @@ impl<'tcx> TraitEngine<'tcx> for FulfillmentContext<'tcx> { &mut self, infcx: &InferCtxt<'_, 'tcx>, ) -> Vec<FulfillmentError<'tcx>> { - let mut selcx = SelectionContext::new(infcx); - self.select(&mut selcx) + let selcx = SelectionContext::new(infcx); + self.select(selcx) } fn pending_obligations(&self) -> Vec<PredicateObligation<'tcx>> { @@ -210,8 +210,8 @@ impl<'tcx> TraitEngine<'tcx> for FulfillmentContext<'tcx> { } } -struct FulfillProcessor<'a, 'b, 'tcx> { - selcx: &'a mut SelectionContext<'b, 'tcx>, +struct FulfillProcessor<'a, 'tcx> { + selcx: SelectionContext<'a, 'tcx>, } fn mk_pending(os: Vec<PredicateObligation<'_>>) -> Vec<PendingPredicateObligation<'_>> { @@ -220,7 +220,7 @@ fn mk_pending(os: Vec<PredicateObligation<'_>>) -> Vec<PendingPredicateObligatio .collect() } -impl<'a, 'b, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'b, 'tcx> { +impl<'a, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'tcx> { type Obligation = PendingPredicateObligation<'tcx>; type Error = FulfillmentErrorCode<'tcx>; type OUT = Outcome<Self::Obligation, Self::Error>; @@ -279,7 +279,7 @@ impl<'a, 'b, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'b, 'tcx> { debug!(?obligation, "pre-resolve"); - if obligation.predicate.has_infer_types_or_consts() { + if obligation.predicate.has_non_region_infer() { obligation.predicate = self.selcx.infcx().resolve_vars_if_possible(obligation.predicate); } @@ -291,7 +291,7 @@ impl<'a, 'b, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'b, 'tcx> { if obligation.predicate.has_projections() { let mut obligations = Vec::new(); let predicate = crate::traits::project::try_normalize_with_depth_to( - self.selcx, + &mut self.selcx, obligation.param_env, obligation.cause.clone(), obligation.recursion_depth + 1, @@ -569,7 +569,7 @@ impl<'a, 'b, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'b, 'tcx> { ) } (Err(ErrorHandled::TooGeneric), _) | (_, Err(ErrorHandled::TooGeneric)) => { - if c1.has_infer_types_or_consts() || c2.has_infer_types_or_consts() { + if c1.has_non_region_infer() || c2.has_non_region_infer() { ProcessResult::Unchanged } else { // Two different constants using generic parameters ~> error. @@ -608,7 +608,7 @@ impl<'a, 'b, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'b, 'tcx> { } } -impl<'a, 'b, 'tcx> FulfillProcessor<'a, 'b, 'tcx> { +impl<'a, 'tcx> FulfillProcessor<'a, 'tcx> { #[instrument(level = "debug", skip(self, obligation, stalled_on))] fn process_trait_obligation( &mut self, @@ -643,7 +643,7 @@ impl<'a, 'b, 'tcx> FulfillProcessor<'a, 'b, 'tcx> { // information about the types in the trait. stalled_on.clear(); stalled_on.extend(substs_infer_vars( - self.selcx, + &self.selcx, trait_obligation.predicate.map_bound(|pred| pred.trait_ref.substs), )); @@ -695,12 +695,12 @@ impl<'a, 'b, 'tcx> FulfillProcessor<'a, 'b, 'tcx> { } } - match project::poly_project_and_unify_type(self.selcx, &project_obligation) { + match project::poly_project_and_unify_type(&mut self.selcx, &project_obligation) { ProjectAndUnifyResult::Holds(os) => ProcessResult::Changed(mk_pending(os)), ProjectAndUnifyResult::FailedNormalization => { stalled_on.clear(); stalled_on.extend(substs_infer_vars( - self.selcx, + &self.selcx, project_obligation.predicate.map_bound(|pred| pred.projection_ty.substs), )); ProcessResult::Unchanged @@ -718,7 +718,7 @@ impl<'a, 'b, 'tcx> FulfillProcessor<'a, 'b, 'tcx> { /// Returns the set of inference variables contained in `substs`. fn substs_infer_vars<'a, 'tcx>( - selcx: &mut SelectionContext<'a, 'tcx>, + selcx: &SelectionContext<'a, 'tcx>, substs: ty::Binder<'tcx, SubstsRef<'tcx>>, ) -> impl Iterator<Item = TyOrConstInferVar<'tcx>> { selcx @@ -726,11 +726,11 @@ fn substs_infer_vars<'a, 'tcx>( .resolve_vars_if_possible(substs) .skip_binder() // ok because this check doesn't care about regions .iter() - .filter(|arg| arg.has_infer_types_or_consts()) + .filter(|arg| arg.has_non_region_infer()) .flat_map(|arg| { let mut walker = arg.walk(); while let Some(c) = walker.next() { - if !c.has_infer_types_or_consts() { + if !c.has_non_region_infer() { walker.visited.remove(&c); walker.skip_current_subtree(); } diff --git a/compiler/rustc_trait_selection/src/traits/misc.rs b/compiler/rustc_trait_selection/src/traits/misc.rs index e1bd48ba8ac..41b742734cd 100644 --- a/compiler/rustc_trait_selection/src/traits/misc.rs +++ b/compiler/rustc_trait_selection/src/traits/misc.rs @@ -57,7 +57,7 @@ pub fn can_type_implement_copy<'tcx>( // to begin with, and point to the bad field's span instead. let cause = if field .ty(tcx, traits::InternalSubsts::identity_for_item(tcx, adt.did())) - .has_param_types_or_consts() + .has_non_region_param() { parent_cause.clone() } else { diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs index 8da68c225d8..659ffc178aa 100644 --- a/compiler/rustc_trait_selection/src/traits/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/mod.rs @@ -170,7 +170,7 @@ pub fn type_known_to_meet_bound_modulo_regions<'a, 'tcx>( result ); - if result && ty.has_infer_types_or_consts() { + if result && ty.has_non_region_infer() { // Because of inference "guessing", selection can sometimes claim // to succeed while the success requires a guess. To ensure // this function's result remains infallible, we must confirm diff --git a/compiler/rustc_trait_selection/src/traits/object_safety.rs b/compiler/rustc_trait_selection/src/traits/object_safety.rs index a54b725753c..8f87a7fdeba 100644 --- a/compiler/rustc_trait_selection/src/traits/object_safety.rs +++ b/compiler/rustc_trait_selection/src/traits/object_safety.rs @@ -14,7 +14,7 @@ use crate::infer::TyCtxtInferExt; use crate::traits::query::evaluate_obligation::InferCtxtExt; use crate::traits::{self, Obligation, ObligationCause}; use hir::def::DefKind; -use rustc_errors::{FatalError, MultiSpan}; +use rustc_errors::{DelayDm, FatalError, MultiSpan}; use rustc_hir as hir; use rustc_hir::def_id::DefId; use rustc_middle::ty::abstract_const::{walk_abstract_const, AbstractConst}; @@ -164,37 +164,42 @@ fn lint_object_unsafe_trait( ) { // Using `CRATE_NODE_ID` is wrong, but it's hard to get a more precise id. // It's also hard to get a use site span, so we use the method definition span. - tcx.struct_span_lint_hir(WHERE_CLAUSES_OBJECT_SAFETY, hir::CRATE_HIR_ID, span, |lint| { - let mut err = lint.build(&format!( - "the trait `{}` cannot be made into an object", - tcx.def_path_str(trait_def_id) - )); - let node = tcx.hir().get_if_local(trait_def_id); - let mut spans = MultiSpan::from_span(span); - if let Some(hir::Node::Item(item)) = node { - spans.push_span_label(item.ident.span, "this trait cannot be made into an object..."); - spans.push_span_label(span, format!("...because {}", violation.error_msg())); - } else { - spans.push_span_label( - span, - format!( - "the trait cannot be made into an object because {}", - violation.error_msg() - ), + tcx.struct_span_lint_hir( + WHERE_CLAUSES_OBJECT_SAFETY, + hir::CRATE_HIR_ID, + span, + DelayDm(|| format!("the trait `{}` cannot be made into an object", tcx.def_path_str(trait_def_id))), + |err| { + let node = tcx.hir().get_if_local(trait_def_id); + let mut spans = MultiSpan::from_span(span); + if let Some(hir::Node::Item(item)) = node { + spans.push_span_label( + item.ident.span, + "this trait cannot be made into an object...", + ); + spans.push_span_label(span, format!("...because {}", violation.error_msg())); + } else { + spans.push_span_label( + span, + format!( + "the trait cannot be made into an object because {}", + violation.error_msg() + ), + ); + }; + err.span_note( + spans, + "for a trait to be \"object safe\" it needs to allow building a vtable to allow the \ + call to be resolvable dynamically; for more information visit \ + <https://doc.rust-lang.org/reference/items/traits.html#object-safety>", ); - }; - err.span_note( - spans, - "for a trait to be \"object safe\" it needs to allow building a vtable to allow the \ - call to be resolvable dynamically; for more information visit \ - <https://doc.rust-lang.org/reference/items/traits.html#object-safety>", - ); - if node.is_some() { - // Only provide the help if its a local trait, otherwise it's not - violation.solution(&mut err); - } - err.emit(); - }); + if node.is_some() { + // Only provide the help if its a local trait, otherwise it's not + violation.solution(err); + } + err + }, + ); } fn sized_trait_bound_spans<'tcx>( @@ -838,7 +843,10 @@ fn contains_illegal_self_type_reference<'tcx, T: TypeVisitable<'tcx>>( } } - fn visit_unevaluated(&mut self, uv: ty::Unevaluated<'tcx>) -> ControlFlow<Self::BreakTy> { + fn visit_ty_unevaluated( + &mut self, + uv: ty::UnevaluatedConst<'tcx>, + ) -> ControlFlow<Self::BreakTy> { // Constants can only influence object safety if they reference `Self`. // This is only possible for unevaluated constants, so we walk these here. // @@ -852,7 +860,7 @@ fn contains_illegal_self_type_reference<'tcx, T: TypeVisitable<'tcx>>( // This shouldn't really matter though as we can't really use any // constants which are not considered const evaluatable. use rustc_middle::ty::abstract_const::Node; - if let Ok(Some(ct)) = AbstractConst::new(self.tcx, uv.shrink()) { + if let Ok(Some(ct)) = AbstractConst::new(self.tcx, uv) { walk_abstract_const(self.tcx, ct, |node| match node.root(self.tcx) { Node::Leaf(leaf) => self.visit_const(leaf), Node::Cast(_, _, ty) => self.visit_ty(ty), diff --git a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs index a4b54018228..3008dfcadde 100644 --- a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs +++ b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs @@ -46,7 +46,7 @@ impl<'a, 'cx, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'cx, 'tcx> { /// Note that this may cause outlives obligations to be injected /// into the inference context with this body-id. /// - `ty`, the type that we are supposed to assume is WF. - #[instrument(level = "debug", skip(self, param_env, body_id))] + #[instrument(level = "debug", skip(self, param_env, body_id), ret)] fn implied_outlives_bounds( &self, param_env: ty::ParamEnv<'tcx>, @@ -71,6 +71,7 @@ impl<'a, 'cx, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'cx, 'tcx> { let TypeOpOutput { output, constraints, .. } = result; if let Some(constraints) = constraints { + debug!(?constraints); // Instantiation may have produced new inference variables and constraints on those // variables. Process these constraints. let mut fulfill_cx = <dyn TraitEngine<'tcx>>::new(self.tcx); diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs index ed83847e880..085045bcdcb 100644 --- a/compiler/rustc_trait_selection/src/traits/project.rs +++ b/compiler/rustc_trait_selection/src/traits/project.rs @@ -1488,7 +1488,7 @@ fn assemble_candidates_from_predicates<'cx, 'tcx>( candidate_set.push_candidate(ctor(data)); if potentially_unnormalized_candidates - && !obligation.predicate.has_infer_types_or_consts() + && !obligation.predicate.has_non_region_infer() { // HACK: Pick the first trait def candidate for a fully // inferred predicate. This is to allow duplicates that @@ -2141,15 +2141,15 @@ fn confirm_impl_candidate<'cx, 'tcx>( let identity_substs = crate::traits::InternalSubsts::identity_for_item(tcx, assoc_ty.item.def_id); let did = ty::WithOptConstParam::unknown(assoc_ty.item.def_id); - let kind = ty::ConstKind::Unevaluated(ty::Unevaluated::new(did, identity_substs)); + let kind = ty::ConstKind::Unevaluated(ty::UnevaluatedConst::new(did, identity_substs)); ty.map_bound(|ty| tcx.mk_const(ty::ConstS { ty, kind }).into()) } else { ty.map_bound(|ty| ty.into()) }; - if substs.len() != tcx.generics_of(assoc_ty.item.def_id).count() { + if !check_substs_compatible(tcx, &assoc_ty.item, substs) { let err = tcx.ty_error_with_message( obligation.cause.span, - "impl item and trait item have different parameter counts", + "impl item and trait item have different parameters", ); Progress { term: err.into(), obligations: nested } } else { @@ -2158,6 +2158,44 @@ fn confirm_impl_candidate<'cx, 'tcx>( } } +// Verify that the trait item and its implementation have compatible substs lists +fn check_substs_compatible<'tcx>( + tcx: TyCtxt<'tcx>, + assoc_ty: &ty::AssocItem, + substs: ty::SubstsRef<'tcx>, +) -> bool { + fn check_substs_compatible_inner<'tcx>( + tcx: TyCtxt<'tcx>, + generics: &'tcx ty::Generics, + args: &'tcx [ty::GenericArg<'tcx>], + ) -> bool { + if generics.count() != args.len() { + return false; + } + + let (parent_args, own_args) = args.split_at(generics.parent_count); + + if let Some(parent) = generics.parent + && let parent_generics = tcx.generics_of(parent) + && !check_substs_compatible_inner(tcx, parent_generics, parent_args) { + return false; + } + + for (param, arg) in std::iter::zip(&generics.params, own_args) { + match (¶m.kind, arg.unpack()) { + (ty::GenericParamDefKind::Type { .. }, ty::GenericArgKind::Type(_)) + | (ty::GenericParamDefKind::Lifetime, ty::GenericArgKind::Lifetime(_)) + | (ty::GenericParamDefKind::Const { .. }, ty::GenericArgKind::Const(_)) => {} + _ => return false, + } + } + + true + } + + check_substs_compatible_inner(tcx, tcx.generics_of(assoc_ty.def_id), substs.as_slice()) +} + fn confirm_impl_trait_in_trait_candidate<'tcx>( selcx: &mut SelectionContext<'_, 'tcx>, obligation: &ProjectionTyObligation<'tcx>, diff --git a/compiler/rustc_trait_selection/src/traits/query/normalize.rs b/compiler/rustc_trait_selection/src/traits/query/normalize.rs index 77f83b3f542..31e7fb67f0e 100644 --- a/compiler/rustc_trait_selection/src/traits/query/normalize.rs +++ b/compiler/rustc_trait_selection/src/traits/query/normalize.rs @@ -351,25 +351,7 @@ impl<'cx, 'tcx> FallibleTypeFolder<'tcx> for QueryNormalizer<'cx, 'tcx> { &mut self, constant: mir::ConstantKind<'tcx>, ) -> Result<mir::ConstantKind<'tcx>, Self::Error> { - Ok(match constant { - mir::ConstantKind::Ty(c) => { - let const_folded = c.try_super_fold_with(self)?; - match const_folded.kind() { - ty::ConstKind::Value(valtree) => { - let tcx = self.infcx.tcx; - let ty = const_folded.ty(); - let const_val = tcx.valtree_to_const_val((ty, valtree)); - debug!(?ty, ?valtree, ?const_val); - - mir::ConstantKind::Val(const_val, ty) - } - _ => mir::ConstantKind::Ty(const_folded), - } - } - mir::ConstantKind::Val(_, _) | mir::ConstantKind::Unevaluated(..) => { - constant.try_super_fold_with(self)? - } - }) + constant.try_super_fold_with(self) } #[inline] diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs index 451427a6980..9a8331614b0 100644 --- a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs +++ b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs @@ -6,6 +6,7 @@ //! //! [rustc dev guide]:https://rustc-dev-guide.rust-lang.org/traits/resolution.html#candidate-assembly use hir::LangItem; +use rustc_errors::DelayDm; use rustc_hir as hir; use rustc_hir::def_id::DefId; use rustc_infer::traits::ObligationCause; @@ -173,7 +174,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { debug!(?stack, ?candidates, "winnowed to {} candidates", candidates.len()); - let needs_infer = stack.obligation.predicate.has_infer_types_or_consts(); + let needs_infer = stack.obligation.predicate.has_non_region_infer(); // If there are STILL multiple candidates, we can further // reduce the list by dropping duplicates -- including @@ -825,13 +826,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { DEREF_INTO_DYN_SUPERTRAIT, obligation.cause.body_id, obligation.cause.span, - |lint| { - lint.build(&format!( - "`{}` implements `Deref` with supertrait `{}` as output", - source, - deref_output_ty - )).emit(); - }, + DelayDm(|| format!( + "`{}` implements `Deref` with supertrait `{}` as output", + source, deref_output_ty + )), + |lint| lint, ); return; } @@ -890,11 +889,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { obligation: &TraitObligation<'tcx>, candidates: &mut SelectionCandidateSet<'tcx>, ) { - if obligation.has_param_types_or_consts() { + if obligation.has_non_region_param() { return; } - if obligation.has_infer_types_or_consts() { + if obligation.has_non_region_infer() { candidates.ambiguous = true; return; } diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs index e08f03a270c..5c8a76401d2 100644 --- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs +++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs @@ -11,9 +11,10 @@ use rustc_hir::lang_items::LangItem; use rustc_index::bit_set::GrowableBitSet; use rustc_infer::infer::InferOk; use rustc_infer::infer::LateBoundRegionConversionTime::HigherRankedType; -use rustc_middle::ty::{self, GenericParamDefKind, Ty, TyCtxt}; -use rustc_middle::ty::{GenericArg, GenericArgKind, InternalSubsts, SubstsRef}; -use rustc_middle::ty::{ToPolyTraitRef, ToPredicate}; +use rustc_middle::ty::{ + self, GenericArg, GenericArgKind, GenericParamDefKind, InternalSubsts, SubstsRef, + ToPolyTraitRef, ToPredicate, Ty, TyCtxt, +}; use rustc_span::def_id::DefId; use crate::traits::project::{normalize_with_depth, normalize_with_depth_to}; @@ -289,8 +290,10 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let scope = type_at(2).skip_binder(); - let assume = - rustc_transmute::Assume::from_const(self.infcx.tcx, obligation.param_env, const_at(3)); + let Some(assume) = + rustc_transmute::Assume::from_const(self.infcx.tcx, obligation.param_env, const_at(3)) else { + return Err(Unimplemented); + }; let cause = obligation.cause.clone(); @@ -626,7 +629,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { // the signature, as evidenced by how we treat it during projection. // The safe thing to do here is to liberate it, though, which should // have no worse effect than skipping the binder here. - let liberated_fn_ty = self.infcx.replace_bound_vars_with_placeholders(obligation.self_ty()); + let liberated_fn_ty = + self.infcx.replace_bound_vars_with_placeholders(obligation.predicate.rebind(self_ty)); let output_ty = self .infcx .replace_bound_vars_with_placeholders(liberated_fn_ty.fn_sig(self.tcx()).output()); @@ -1224,6 +1228,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { | ty::Never | ty::Foreign(_) => {} + // `ManuallyDrop` is trivially drop + ty::Adt(def, _) if Some(def.did()) == tcx.lang_items().manually_drop() => {} + // These types are built-in, so we can fast-track by registering // nested predicates for their constituent type(s) ty::Array(ty, _) | ty::Slice(ty) => { diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index 5e32a27cdb1..8f2a6f337ba 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -35,7 +35,6 @@ use rustc_middle::mir::interpret::ErrorHandled; use rustc_middle::ty::abstract_const::NotConstEvaluatable; use rustc_middle::ty::fast_reject::{DeepRejectCtxt, TreatParams}; use rustc_middle::ty::fold::BottomUpFolder; -use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::relate::TypeRelation; use rustc_middle::ty::SubstsRef; use rustc_middle::ty::{self, EarlyBinder, PolyProjectionPredicate, ToPolyTraitRef, ToPredicate}; @@ -729,7 +728,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { ) } (Err(ErrorHandled::TooGeneric), _) | (_, Err(ErrorHandled::TooGeneric)) => { - if c1.has_infer_types_or_consts() || c2.has_infer_types_or_consts() { + if c1.has_non_region_infer() || c2.has_non_region_infer() { Ok(EvaluatedToAmbig) } else { // Two different constants using generic parameters ~> error. @@ -914,38 +913,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let unbound_input_types = stack.fresh_trait_pred.skip_binder().trait_ref.substs.types().any(|ty| ty.is_fresh()); - if stack.obligation.polarity() != ty::ImplPolarity::Negative { - // This check was an imperfect workaround for a bug in the old - // intercrate mode; it should be removed when that goes away. - if unbound_input_types && self.intercrate { - debug!("evaluate_stack --> unbound argument, intercrate --> ambiguous",); - // Heuristics: show the diagnostics when there are no candidates in crate. - if self.intercrate_ambiguity_causes.is_some() { - debug!("evaluate_stack: intercrate_ambiguity_causes is some"); - if let Ok(candidate_set) = self.assemble_candidates(stack) { - if !candidate_set.ambiguous && candidate_set.vec.is_empty() { - let trait_ref = stack.obligation.predicate.skip_binder().trait_ref; - let self_ty = trait_ref.self_ty(); - let cause = with_no_trimmed_paths!({ - IntercrateAmbiguityCause::DownstreamCrate { - trait_desc: trait_ref.print_only_trait_path().to_string(), - self_desc: if self_ty.has_concrete_skeleton() { - Some(self_ty.to_string()) - } else { - None - }, - } - }); - - debug!(?cause, "evaluate_stack: pushing cause"); - self.intercrate_ambiguity_causes.as_mut().unwrap().insert(cause); - } - } - } - return Ok(EvaluatedToAmbig); - } - } - if unbound_input_types && stack.iter().skip(1).any(|prev| { stack.obligation.param_env == prev.obligation.param_env @@ -1553,7 +1520,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { if !generics.params.is_empty() && obligation.predicate.substs[generics.parent_count..] .iter() - .any(|&p| p.has_infer_types_or_consts() && self.infcx.shallow_resolve(p) != p) + .any(|&p| p.has_non_region_infer() && self.infcx.shallow_resolve(p) != p) { ProjectionMatchesProjection::Ambiguous } else { @@ -1737,12 +1704,12 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { (&ImplCandidate(other_def), &ImplCandidate(victim_def)) => { // See if we can toss out `victim` based on specialization. - // This requires us to know *for sure* that the `other` impl applies - // i.e., `EvaluatedToOk`. + // While this requires us to know *for sure* that the `other` impl applies + // we still use modulo regions here. // - // FIXME(@lcnr): Using `modulo_regions` here seems kind of scary - // to me but is required for `std` to compile, so I didn't change it - // for now. + // This is fine as specialization currently assumes that specializing + // impls have to be always applicable, meaning that the only allowed + // region constraints may be constraints also present on the default impl. let tcx = self.tcx(); if other.evaluation.must_apply_modulo_regions() { if tcx.specializes((other_def, victim_def)) { diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs index 56a88749c46..eac3f0f30e8 100644 --- a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs @@ -17,7 +17,7 @@ use crate::infer::{InferCtxt, InferOk, TyCtxtInferExt}; use crate::traits::select::IntercrateAmbiguityCause; use crate::traits::{self, coherence, FutureCompatOverlapErrorKind, ObligationCause}; use rustc_data_structures::fx::{FxHashSet, FxIndexSet}; -use rustc_errors::{struct_span_err, EmissionGuarantee, LintDiagnosticBuilder}; +use rustc_errors::{struct_span_err, DiagnosticBuilder, EmissionGuarantee}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_middle::ty::{self, ImplSubject, TyCtxt}; use rustc_middle::ty::{InternalSubsts, SubstsRef}; @@ -350,26 +350,12 @@ fn report_conflicting_impls( // Work to be done after we've built the DiagnosticBuilder. We have to define it // now because the struct_lint methods don't return back the DiagnosticBuilder // that's passed in. - fn decorate<G: EmissionGuarantee>( + fn decorate<'a, 'b, G: EmissionGuarantee>( tcx: TyCtxt<'_>, overlap: OverlapError, - used_to_be_allowed: Option<FutureCompatOverlapErrorKind>, impl_span: Span, - err: LintDiagnosticBuilder<'_, G>, - ) -> G { - let msg = format!( - "conflicting implementations of trait `{}`{}{}", - overlap.trait_desc, - overlap - .self_desc - .clone() - .map_or_else(String::new, |ty| { format!(" for type `{}`", ty) }), - match used_to_be_allowed { - Some(FutureCompatOverlapErrorKind::Issue33140) => ": (E0119)", - _ => "", - } - ); - let mut err = err.build(&msg); + err: &'b mut DiagnosticBuilder<'a, G>, + ) -> &'b mut DiagnosticBuilder<'a, G> { match tcx.span_of_impl(overlap.with_impl) { Ok(span) => { err.span_label(span, "first implementation here"); @@ -384,7 +370,9 @@ fn report_conflicting_impls( } Err(cname) => { let msg = match to_pretty_impl_header(tcx, overlap.with_impl) { - Some(s) => format!("conflicting implementation in crate `{}`:\n- {}", cname, s), + Some(s) => { + format!("conflicting implementation in crate `{}`:\n- {}", cname, s) + } None => format!("conflicting implementation in crate `{}`", cname), }; err.note(&msg); @@ -392,28 +380,33 @@ fn report_conflicting_impls( } for cause in &overlap.intercrate_ambiguity_causes { - cause.add_intercrate_ambiguity_hint(&mut err); + cause.add_intercrate_ambiguity_hint(err); } if overlap.involves_placeholder { - coherence::add_placeholder_note(&mut err); + coherence::add_placeholder_note(err); } - err.emit() + err } + let msg = format!( + "conflicting implementations of trait `{}`{}{}", + overlap.trait_desc, + overlap.self_desc.as_deref().map_or_else(String::new, |ty| format!(" for type `{ty}`")), + match used_to_be_allowed { + Some(FutureCompatOverlapErrorKind::Issue33140) => ": (E0119)", + _ => "", + } + ); + match used_to_be_allowed { None => { let reported = if overlap.with_impl.is_local() || tcx.orphan_check_impl(impl_def_id).is_ok() { - let err = struct_span_err!(tcx.sess, impl_span, E0119, ""); - Some(decorate( - tcx, - overlap, - used_to_be_allowed, - impl_span, - LintDiagnosticBuilder::new(err), - )) + let mut err = struct_span_err!(tcx.sess, impl_span, E0119, "{msg}",); + decorate(tcx, overlap, impl_span, &mut err); + Some(err.emit()) } else { Some(tcx.sess.delay_span_bug(impl_span, "impl should have failed the orphan check")) }; @@ -428,9 +421,8 @@ fn report_conflicting_impls( lint, tcx.hir().local_def_id_to_hir_id(impl_def_id), impl_span, - |ldb| { - decorate(tcx, overlap, used_to_be_allowed, impl_span, ldb); - }, + msg, + |err| decorate(tcx, overlap, impl_span, err), ); } }; diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs index 9722b48a68a..5f901d6995e 100644 --- a/compiler/rustc_trait_selection/src/traits/wf.rs +++ b/compiler/rustc_trait_selection/src/traits/wf.rs @@ -308,6 +308,32 @@ impl<'tcx> WfPredicates<'tcx> { let obligations = if trait_pred.constness == ty::BoundConstness::NotConst { self.nominal_obligations_without_const(trait_ref.def_id, trait_ref.substs) } else { + if !tcx.has_attr(trait_ref.def_id, rustc_span::sym::const_trait) { + if let Some(item) = self.item && + let hir::ItemKind::Impl(impl_) = item.kind && + let Some(trait_) = &impl_.of_trait && + let Some(def_id) = trait_.trait_def_id() && + def_id == trait_ref.def_id + { + let trait_name = tcx.item_name(def_id); + let mut err = tcx.sess.struct_span_err( + self.span, + &format!("const `impl` for trait `{trait_name}` which is not marked with `#[const_trait]`"), + ); + if def_id.is_local() { + let sp = tcx.def_span(def_id).shrink_to_lo(); + err.span_suggestion(sp, &format!("mark `{trait_name}` as const"), "#[const_trait]", rustc_errors::Applicability::MachineApplicable); + } + err.note("marking a trait with `#[const_trait]` ensures all default method bodies are `const`"); + err.note("adding a non-const method body in the future would be a breaking change"); + err.emit(); + } else { + tcx.sess.span_err( + self.span, + "~const can only be applied to `#[const_trait]` traits", + ); + } + } self.nominal_obligations(trait_ref.def_id, trait_ref.substs) }; |