diff --git a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs index b53099b0abbb7..3853b95f78b4c 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs @@ -1,3 +1,5 @@ +use core::ops::ControlFlow; + use rustc_abi::{FieldIdx, VariantIdx}; use rustc_apfloat::Float; use rustc_data_structures::fx::FxHashSet; @@ -187,7 +189,7 @@ impl<'tcx> ConstToPat<'tcx> { if !inlined_const_as_pat.references_error() { // Always check for `PartialEq` if we had no other errors yet. - if !type_has_partial_eq_impl(self.tcx, typing_env, ty).0 { + if !type_has_partial_eq_impl(self.tcx, typing_env, ty).has_impl { let mut err = self.tcx.dcx().create_err(TypeNotPartialEq { span: self.span, ty }); extend_type_not_partial_eq(self.tcx, typing_env, ty, &mut err); return self.mk_err(err, ty); @@ -221,12 +223,13 @@ impl<'tcx> ConstToPat<'tcx> { // Extremely important check for all ADTs! Make sure they opted-in to be used in // patterns. debug!("adt_def {:?} has !type_marked_structural for cv.ty: {:?}", adt_def, ty); - let (_impls_partial_eq, derived, structural, impl_def_id) = - type_has_partial_eq_impl(self.tcx, self.typing_env, ty); + let PartialEqImplStatus { + is_derived, structural_partial_eq, non_blanket_impl, .. + } = type_has_partial_eq_impl(self.tcx, self.typing_env, ty); let (manual_partialeq_impl_span, manual_partialeq_impl_note) = - match (structural, impl_def_id) { + match (structural_partial_eq, non_blanket_impl) { (true, _) => (None, false), - (_, Some(def_id)) if def_id.is_local() && !derived => { + (_, Some(def_id)) if def_id.is_local() && !is_derived => { (Some(tcx.def_span(def_id)), false) } _ => (None, true), @@ -385,40 +388,46 @@ fn extend_type_not_partial_eq<'tcx>( /// The type has no `PartialEq` implementation, neither manual or derived, but /// we don't have a span to point at, so we'll just add them as a `note`. without: FxHashSet>, - /// If any of the subtypes has escaping bounds (`for<'a>`), we won't emit a note. - has_escaping_bound_vars: bool, } impl<'tcx> TypeVisitor> for UsedParamsNeedInstantiationVisitor<'tcx> { + type Result = ControlFlow<()>; fn visit_ty(&mut self, ty: Ty<'tcx>) -> Self::Result { - if ty.has_escaping_bound_vars() { - self.has_escaping_bound_vars = true; - } else if let ty::Adt(def, _args) = ty.kind() { - let ty_def_id = def.did(); - let ty_def_span = self.tcx.def_span(ty_def_id); - let (impls_partial_eq, derived, structural, impl_def_id) = - type_has_partial_eq_impl(self.tcx, self.typing_env, ty); - match (impls_partial_eq, derived, structural, impl_def_id) { - (_, _, true, _) => {} - (true, false, _, Some(def_id)) if def_id.is_local() => { - self.adts_with_manual_partialeq.insert(self.tcx.def_span(def_id)); - } - (true, false, _, _) if ty_def_id.is_local() => { - self.adts_with_manual_partialeq.insert(ty_def_span); - } - (false, _, _, _) if ty_def_id.is_local() => { - self.adts_without_partialeq.insert(ty_def_span); - } - (true, false, _, _) => { - self.manual.insert(ty); - } - (false, _, _, _) => { - self.without.insert(ty); - } - _ => {} - }; + match ty.kind() { + ty::Dynamic(..) => return ControlFlow::Break(()), + ty::FnPtr(..) => return ControlFlow::Continue(()), + ty::Adt(def, _args) => { + let ty_def_id = def.did(); + let ty_def_span = self.tcx.def_span(ty_def_id); + let PartialEqImplStatus { + has_impl, + is_derived, + structural_partial_eq, + non_blanket_impl, + } = type_has_partial_eq_impl(self.tcx, self.typing_env, ty); + match (has_impl, is_derived, structural_partial_eq, non_blanket_impl) { + (_, _, true, _) => {} + (true, false, _, Some(def_id)) if def_id.is_local() => { + self.adts_with_manual_partialeq.insert(self.tcx.def_span(def_id)); + } + (true, false, _, _) if ty_def_id.is_local() => { + self.adts_with_manual_partialeq.insert(ty_def_span); + } + (false, _, _, _) if ty_def_id.is_local() => { + self.adts_without_partialeq.insert(ty_def_span); + } + (true, false, _, _) => { + self.manual.insert(ty); + } + (false, _, _, _) => { + self.without.insert(ty); + } + _ => {} + }; + ty.super_visit_with(self) + } + _ => ty.super_visit_with(self), } - ty.super_visit_with(self) } } let mut v = UsedParamsNeedInstantiationVisitor { @@ -428,10 +437,8 @@ fn extend_type_not_partial_eq<'tcx>( adts_without_partialeq: FxHashSet::default(), manual: FxHashSet::default(), without: FxHashSet::default(), - has_escaping_bound_vars: false, }; - v.visit_ty(ty); - if v.has_escaping_bound_vars { + if v.visit_ty(ty).is_break() { return; } #[allow(rustc::potential_query_instability)] // Span labels will be sorted by the rendering @@ -445,31 +452,38 @@ fn extend_type_not_partial_eq<'tcx>( "must be annotated with `#[derive(PartialEq)]` to be usable in patterns", ); } - #[allow(rustc::potential_query_instability)] // Span labels will be sorted by the rendering - for ty in v.manual { + #[allow(rustc::potential_query_instability)] + let mut manual: Vec<_> = v.manual.into_iter().map(|t| t.to_string()).collect(); + manual.sort(); + for ty in manual { err.note(format!( "`{ty}` must be annotated with `#[derive(PartialEq)]` to be usable in patterns, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details" )); } - #[allow(rustc::potential_query_instability)] // Span labels will be sorted by the rendering - for ty in v.without { + #[allow(rustc::potential_query_instability)] + let mut without: Vec<_> = v.without.into_iter().map(|t| t.to_string()).collect(); + without.sort(); + for ty in without { err.note(format!( "`{ty}` must be annotated with `#[derive(PartialEq)]` to be usable in patterns" )); } } +#[derive(Debug)] +struct PartialEqImplStatus { + has_impl: bool, + is_derived: bool, + structural_partial_eq: bool, + non_blanket_impl: Option, +} + #[instrument(level = "trace", skip(tcx), ret)] fn type_has_partial_eq_impl<'tcx>( tcx: TyCtxt<'tcx>, typing_env: ty::TypingEnv<'tcx>, ty: Ty<'tcx>, -) -> ( - /* has impl */ bool, - /* is derived */ bool, - /* structural partial eq */ bool, - /* non-blanket impl */ Option, -) { +) -> PartialEqImplStatus { let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(typing_env); // double-check there even *is* a semantic `PartialEq` to dispatch to. // @@ -479,10 +493,6 @@ fn type_has_partial_eq_impl<'tcx>( let partial_eq_trait_id = tcx.require_lang_item(hir::LangItem::PartialEq, None); let structural_partial_eq_trait_id = tcx.require_lang_item(hir::LangItem::StructuralPeq, None); - if ty.has_escaping_bound_vars() { - return (false, false, false, None); - } - let partial_eq_obligation = Obligation::new( tcx, ObligationCause::dummy(), @@ -510,10 +520,10 @@ fn type_has_partial_eq_impl<'tcx>( // that patterns can only do things that the code could also do without patterns, but it is // needed for backwards compatibility. The actual pattern matching compares primitive values, // `PartialEq::eq` never gets invoked, so there's no risk of us running non-const code. - ( - infcx.predicate_must_hold_modulo_regions(&partial_eq_obligation), - automatically_derived, - structural_peq, - impl_def_id, - ) + PartialEqImplStatus { + has_impl: infcx.predicate_must_hold_modulo_regions(&partial_eq_obligation), + is_derived: automatically_derived, + structural_partial_eq: structural_peq, + non_blanket_impl: impl_def_id, + } }