From 791ce0b7b5d03649bc9014d5b0abb78f3c6f2cfd Mon Sep 17 00:00:00 2001 From: lcnr Date: Tue, 14 Mar 2023 14:19:06 +0100 Subject: [PATCH 1/3] remove some trait solver helpers they add more complexity then they are worth. It's confusing which of these helpers should be used in which context. --- .../src/diagnostics/conflict_errors.rs | 21 ++---- .../rustc_borrowck/src/diagnostics/mod.rs | 1 - .../src/transform/check_consts/qualifs.rs | 7 +- .../rustc_hir_analysis/src/check/intrinsic.rs | 1 + .../src/coherence/builtin.rs | 33 +++++---- .../rustc_hir_analysis/src/hir_wf_check.rs | 42 +++++------ compiler/rustc_hir_analysis/src/lib.rs | 33 +++++---- compiler/rustc_hir_typeck/src/callee.rs | 2 +- compiler/rustc_hir_typeck/src/cast.rs | 4 +- compiler/rustc_hir_typeck/src/coercion.rs | 16 ++--- compiler/rustc_hir_typeck/src/demand.rs | 2 +- .../rustc_hir_typeck/src/expr_use_visitor.rs | 5 +- .../src/fn_ctxt/suggestions.rs | 9 ++- .../src/mem_categorization.rs | 4 +- compiler/rustc_hir_typeck/src/op.rs | 8 ++- compiler/rustc_hir_typeck/src/upvar.rs | 5 +- .../src/for_loops_over_fallibles.rs | 10 ++- compiler/rustc_middle/src/ty/mod.rs | 14 ++++ compiler/rustc_mir_build/src/build/misc.rs | 4 +- .../src/thir/pattern/const_to_pat.rs | 16 ++--- compiler/rustc_trait_selection/src/infer.rs | 35 +++------ .../src/traits/auto_trait.rs | 5 +- .../src/traits/coherence.rs | 5 +- .../rustc_trait_selection/src/traits/mod.rs | 72 ++++--------------- .../src/traits/outlives_bounds.rs | 27 +++---- .../src/traits/query/type_op/custom.rs | 8 +-- .../src/traits/select/confirmation.rs | 44 +++++------- .../src/traits/select/mod.rs | 13 ++-- .../rustc_trait_selection/src/traits/util.rs | 31 +------- compiler/rustc_ty_utils/src/common_traits.rs | 3 +- .../clippy_lints/src/future_not_send.rs | 6 +- 31 files changed, 198 insertions(+), 288 deletions(-) diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs index 7c88205da3b9a..75a3dd0c0f3d6 100644 --- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs @@ -24,6 +24,7 @@ use rustc_span::hygiene::DesugaringKind; use rustc_span::symbol::{kw, sym}; use rustc_span::{BytePos, Span, Symbol}; use rustc_trait_selection::infer::InferCtxtExt; +use rustc_trait_selection::traits::ObligationCtxt; use crate::borrow_set::TwoPhaseActivation; use crate::borrowck_errors; @@ -760,20 +761,12 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { else { return; }; // Try to find predicates on *generic params* that would allow copying `ty` let infcx = tcx.infer_ctxt().build(); - let copy_did = infcx.tcx.require_lang_item(LangItem::Copy, Some(span)); - let cause = ObligationCause::new( - span, - self.mir_def_id(), - rustc_infer::traits::ObligationCauseCode::MiscObligation, - ); - let errors = rustc_trait_selection::traits::fully_solve_bound( - &infcx, - cause, - self.param_env, - // Erase any region vids from the type, which may not be resolved - infcx.tcx.erase_regions(ty), - copy_did, - ); + let ocx = ObligationCtxt::new(&infcx); + let copy_did = tcx.require_lang_item(LangItem::Copy, Some(span)); + let cause = ObligationCause::misc(span, self.mir_def_id()); + + ocx.register_bound(cause, self.param_env, infcx.tcx.erase_regions(ty), copy_did); + let errors = ocx.select_all_or_error(); // Only emit suggestion if all required predicates are on generic let predicates: Result, _> = errors diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs index 611abb01238b8..9f543b71c5fa4 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mod.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs @@ -1078,7 +1078,6 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { self.param_env, tcx.mk_imm_ref(tcx.lifetimes.re_erased, tcx.erase_regions(ty)), def_id, - DUMMY_SP, ) } _ => false, diff --git a/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs index bb4b7ad50b8f2..6758cba2eed34 100644 --- a/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs +++ b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs @@ -9,7 +9,7 @@ use rustc_middle::mir; use rustc_middle::mir::*; use rustc_middle::ty::{self, subst::SubstsRef, AdtDef, Ty}; use rustc_trait_selection::traits::{ - self, ImplSource, Obligation, ObligationCause, SelectionContext, + self, ImplSource, Obligation, ObligationCause, ObligationCtxt, SelectionContext, }; use super::ConstCx; @@ -184,7 +184,10 @@ impl Qualif for NeedsNonConstDrop { } // If we had any errors, then it's bad - !traits::fully_solve_obligations(&infcx, impl_src.nested_obligations()).is_empty() + let ocx = ObligationCtxt::new(&infcx); + ocx.register_obligations(impl_src.nested_obligations()); + let errors = ocx.select_all_or_error(); + !errors.is_empty() } fn in_adt_inherently<'tcx>( diff --git a/compiler/rustc_hir_analysis/src/check/intrinsic.rs b/compiler/rustc_hir_analysis/src/check/intrinsic.rs index 8c364a4f3b2b8..f7aaa7a159ffa 100644 --- a/compiler/rustc_hir_analysis/src/check/intrinsic.rs +++ b/compiler/rustc_hir_analysis/src/check/intrinsic.rs @@ -59,6 +59,7 @@ fn equate_intrinsic_type<'tcx>( require_same_types( tcx, &cause, + ty::ParamEnv::empty(), // FIXME: do all intrinsics have an empty param env? tcx.mk_fn_ptr(tcx.fn_sig(it.owner_id).subst_identity()), fty, ); diff --git a/compiler/rustc_hir_analysis/src/coherence/builtin.rs b/compiler/rustc_hir_analysis/src/coherence/builtin.rs index 0e1cf3e6c6a7d..e57996a467640 100644 --- a/compiler/rustc_hir_analysis/src/coherence/builtin.rs +++ b/compiler/rustc_hir_analysis/src/coherence/builtin.rs @@ -11,13 +11,14 @@ use rustc_hir::ItemKind; use rustc_infer::infer::outlives::env::OutlivesEnvironment; use rustc_infer::infer::{self, RegionResolutionError}; use rustc_infer::infer::{DefineOpaqueTypes, TyCtxtInferExt}; +use rustc_infer::traits::Obligation; use rustc_middle::ty::adjustment::CoerceUnsizedInfo; use rustc_middle::ty::{self, suggest_constraining_type_params, Ty, TyCtxt, TypeVisitableExt}; use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt; use rustc_trait_selection::traits::misc::{ type_allowed_to_implement_copy, CopyImplementationError, InfringingFieldsReason, }; -use rustc_trait_selection::traits::predicate_for_trait_def; +use rustc_trait_selection::traits::ObligationCtxt; use rustc_trait_selection::traits::{self, ObligationCause}; use std::collections::BTreeMap; @@ -334,19 +335,19 @@ fn visit_implementation_of_dispatch_from_dyn(tcx: TyCtxt<'_>, impl_did: LocalDef )) .emit(); } else { - let errors = traits::fully_solve_obligations( - &infcx, - coerced_fields.into_iter().map(|field| { - predicate_for_trait_def( - tcx, - param_env, - cause.clone(), + let ocx = ObligationCtxt::new(&infcx); + for field in coerced_fields { + ocx.register_obligation(Obligation::new( + tcx, + cause.clone(), + param_env, + ty::Binder::dummy(tcx.mk_trait_ref( dispatch_from_dyn_trait, - 0, [field.ty(tcx, substs_a), field.ty(tcx, substs_b)], - ) - }), - ); + )), + )); + } + let errors = ocx.select_all_or_error(); if !errors.is_empty() { infcx.err_ctxt().report_fulfillment_errors(&errors); } @@ -583,10 +584,12 @@ pub fn coerce_unsized_info<'tcx>(tcx: TyCtxt<'tcx>, impl_did: DefId) -> CoerceUn }; // Register an obligation for `A: Trait`. + let ocx = ObligationCtxt::new(&infcx); let cause = traits::ObligationCause::misc(span, impl_did); - let predicate = - predicate_for_trait_def(tcx, param_env, cause, trait_def_id, 0, [source, target]); - let errors = traits::fully_solve_obligation(&infcx, predicate); + let obligation = + Obligation::new(tcx, cause, param_env, tcx.mk_trait_ref(trait_def_id, [source, target])); + ocx.register_obligation(obligation); + let errors = ocx.select_all_or_error(); if !errors.is_empty() { infcx.err_ctxt().report_fulfillment_errors(&errors); } diff --git a/compiler/rustc_hir_analysis/src/hir_wf_check.rs b/compiler/rustc_hir_analysis/src/hir_wf_check.rs index e330fcc785770..bdd033c5f5f10 100644 --- a/compiler/rustc_hir_analysis/src/hir_wf_check.rs +++ b/compiler/rustc_hir_analysis/src/hir_wf_check.rs @@ -7,7 +7,7 @@ use rustc_infer::traits::{ObligationCause, WellFormedLoc}; use rustc_middle::ty::query::Providers; use rustc_middle::ty::{self, Region, TyCtxt, TypeFoldable, TypeFolder}; use rustc_span::def_id::LocalDefId; -use rustc_trait_selection::traits; +use rustc_trait_selection::traits::{self, ObligationCtxt}; pub fn provide(providers: &mut Providers) { *providers = Providers { diagnostic_hir_wf_check, ..*providers }; @@ -66,35 +66,35 @@ fn diagnostic_hir_wf_check<'tcx>( impl<'tcx> Visitor<'tcx> for HirWfCheck<'tcx> { fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) { let infcx = self.tcx.infer_ctxt().build(); + let ocx = ObligationCtxt::new(&infcx); + let tcx_ty = self.icx.to_ty(ty).fold_with(&mut EraseAllBoundRegions { tcx: self.tcx }); let cause = traits::ObligationCause::new( ty.span, self.def_id, traits::ObligationCauseCode::WellFormed(None), ); - let errors = traits::fully_solve_obligation( - &infcx, - traits::Obligation::new( - self.tcx, - cause, - self.param_env, - ty::Binder::dummy(ty::PredicateKind::WellFormed(tcx_ty.into())), - ), - ); - if !errors.is_empty() { - debug!("Wf-check got errors for {:?}: {:?}", ty, errors); - for error in errors { - if error.obligation.predicate == self.predicate { - // Save the cause from the greatest depth - this corresponds - // to picking more-specific types (e.g. `MyStruct`) - // over less-specific types (e.g. `Option>`) - if self.depth >= self.cause_depth { - self.cause = Some(error.obligation.cause); - self.cause_depth = self.depth - } + + ocx.register_obligation(traits::Obligation::new( + self.tcx, + cause, + self.param_env, + ty::PredicateKind::WellFormed(tcx_ty.into()), + )); + + for error in ocx.select_all_or_error() { + debug!("Wf-check got error for {:?}: {:?}", ty, error); + if error.obligation.predicate == self.predicate { + // Save the cause from the greatest depth - this corresponds + // to picking more-specific types (e.g. `MyStruct`) + // over less-specific types (e.g. `Option>`) + if self.depth >= self.cause_depth { + self.cause = Some(error.obligation.cause); + self.cause_depth = self.depth } } } + self.depth += 1; intravisit::walk_ty(self, ty); self.depth -= 1; diff --git a/compiler/rustc_hir_analysis/src/lib.rs b/compiler/rustc_hir_analysis/src/lib.rs index 08786fe9b1ef9..a3d045c80d164 100644 --- a/compiler/rustc_hir_analysis/src/lib.rs +++ b/compiler/rustc_hir_analysis/src/lib.rs @@ -102,7 +102,7 @@ use rustc_errors::ErrorGuaranteed; use rustc_errors::{DiagnosticMessage, SubdiagnosticMessage}; use rustc_hir as hir; use rustc_hir::Node; -use rustc_infer::infer::{DefineOpaqueTypes, InferOk, TyCtxtInferExt}; +use rustc_infer::infer::TyCtxtInferExt; use rustc_macros::fluent_messages; use rustc_middle::middle; use rustc_middle::ty::query::Providers; @@ -113,7 +113,7 @@ use rustc_span::def_id::{DefId, LocalDefId, CRATE_DEF_ID}; use rustc_span::{symbol::sym, Span, DUMMY_SP}; use rustc_target::spec::abi::Abi; use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _; -use rustc_trait_selection::traits::{self, ObligationCause, ObligationCauseCode}; +use rustc_trait_selection::traits::{self, ObligationCause, ObligationCauseCode, ObligationCtxt}; use std::ops::Not; @@ -160,24 +160,21 @@ fn require_c_abi_if_c_variadic(tcx: TyCtxt<'_>, decl: &hir::FnDecl<'_>, abi: Abi fn require_same_types<'tcx>( tcx: TyCtxt<'tcx>, cause: &ObligationCause<'tcx>, + param_env: ty::ParamEnv<'tcx>, expected: Ty<'tcx>, actual: Ty<'tcx>, -) -> bool { +) { let infcx = &tcx.infer_ctxt().build(); - let param_env = ty::ParamEnv::empty(); - let errors = match infcx.at(cause, param_env).eq(DefineOpaqueTypes::No, expected, actual) { - Ok(InferOk { obligations, .. }) => traits::fully_solve_obligations(infcx, obligations), + let ocx = ObligationCtxt::new(infcx); + match ocx.eq(cause, param_env, expected, actual) { + Ok(()) => { + let errors = ocx.select_all_or_error(); + if !errors.is_empty() { + infcx.err_ctxt().report_fulfillment_errors(&errors); + } + } Err(err) => { infcx.err_ctxt().report_mismatched_types(cause, expected, actual, err).emit(); - return false; - } - }; - - match &errors[..] { - [] => true, - errors => { - infcx.err_ctxt().report_fulfillment_errors(errors); - false } } } @@ -296,6 +293,8 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) { return; } + // Main should have no WC, so empty param env is OK here. + let param_env = ty::ParamEnv::empty(); let expected_return_type; if let Some(term_did) = tcx.lang_items().termination() { let return_ty = main_fnsig.output(); @@ -306,8 +305,6 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) { } let return_ty = return_ty.skip_binder(); let infcx = tcx.infer_ctxt().build(); - // Main should have no WC, so empty param env is OK here. - let param_env = ty::ParamEnv::empty(); let cause = traits::ObligationCause::new( return_ty_span, main_diagnostics_def_id, @@ -343,6 +340,7 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) { main_diagnostics_def_id, ObligationCauseCode::MainFunctionType, ), + param_env, se_ty, tcx.mk_fn_ptr(main_fnsig), ); @@ -417,6 +415,7 @@ fn check_start_fn_ty(tcx: TyCtxt<'_>, start_def_id: DefId) { start_def_id, ObligationCauseCode::StartFunctionType, ), + ty::ParamEnv::empty(), // start should not have any where bounds. se_ty, tcx.mk_fn_ptr(tcx.fn_sig(start_def_id).subst_identity()), ); diff --git a/compiler/rustc_hir_typeck/src/callee.rs b/compiler/rustc_hir_typeck/src/callee.rs index ecbe4a97dd967..5235710a2666e 100644 --- a/compiler/rustc_hir_typeck/src/callee.rs +++ b/compiler/rustc_hir_typeck/src/callee.rs @@ -668,7 +668,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { if !self.maybe_suggest_bad_array_definition(&mut err, call_expr, callee_expr) { if let Some((maybe_def, output_ty, _)) = self.extract_callable_info(callee_ty) - && !self.type_is_sized_modulo_regions(self.param_env, output_ty, callee_expr.span) + && !self.type_is_sized_modulo_regions(self.param_env, output_ty) { let descr = match maybe_def { DefIdOrName::DefId(def_id) => self.tcx.def_descr(def_id), diff --git a/compiler/rustc_hir_typeck/src/cast.rs b/compiler/rustc_hir_typeck/src/cast.rs index 316c2a7eeeb4b..d28b3b3ce7bbd 100644 --- a/compiler/rustc_hir_typeck/src/cast.rs +++ b/compiler/rustc_hir_typeck/src/cast.rs @@ -96,7 +96,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { let t = self.resolve_vars_if_possible(t); t.error_reported()?; - if self.type_is_sized_modulo_regions(self.param_env, t, span) { + if self.type_is_sized_modulo_regions(self.param_env, t) { return Ok(Some(PointerKind::Thin)); } @@ -722,7 +722,7 @@ impl<'a, 'tcx> CastCheck<'tcx> { debug!("check_cast({}, {:?} as {:?})", self.expr.hir_id, self.expr_ty, self.cast_ty); - if !fcx.type_is_sized_modulo_regions(fcx.param_env, self.cast_ty, self.span) + if !fcx.type_is_sized_modulo_regions(fcx.param_env, self.cast_ty) && !self.cast_ty.has_infer_types() { self.report_cast_to_unsized_type(fcx); diff --git a/compiler/rustc_hir_typeck/src/coercion.rs b/compiler/rustc_hir_typeck/src/coercion.rs index a27905ea46c94..8fa3bcd68c3d3 100644 --- a/compiler/rustc_hir_typeck/src/coercion.rs +++ b/compiler/rustc_hir_typeck/src/coercion.rs @@ -46,7 +46,7 @@ use rustc_hir::Expr; use rustc_hir_analysis::astconv::AstConv; use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind}; use rustc_infer::infer::{Coercion, DefineOpaqueTypes, InferOk, InferResult}; -use rustc_infer::traits::Obligation; +use rustc_infer::traits::{Obligation, PredicateObligation}; use rustc_middle::lint::in_external_macro; use rustc_middle::ty::adjustment::{ Adjust, Adjustment, AllowTwoPhase, AutoBorrow, AutoBorrowMutability, PointerCast, @@ -597,13 +597,11 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> { // and almost never more than 3. By using a SmallVec we avoid an // allocation, at the (very small) cost of (occasionally) having to // shift subsequent elements down when removing the front element. - let mut queue: SmallVec<[_; 4]> = smallvec![traits::predicate_for_trait_def( + let mut queue: SmallVec<[PredicateObligation<'tcx>; 4]> = smallvec![Obligation::new( self.tcx, - self.fcx.param_env, cause, - coerce_unsized_did, - 0, - [coerce_source, coerce_target] + self.fcx.param_env, + self.tcx.mk_trait_ref(coerce_unsized_did, [coerce_source, coerce_target]) )]; let mut has_unsized_tuple_coercion = false; @@ -651,9 +649,9 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> { let self_ty = trait_pred.skip_binder().self_ty(); let unsize_ty = trait_pred.skip_binder().trait_ref.substs[1].expect_ty(); debug!("coerce_unsized: ambiguous unsize case for {:?}", trait_pred); - match (&self_ty.kind(), &unsize_ty.kind()) { - (ty::Infer(ty::TyVar(v)), ty::Dynamic(..)) - if self.type_var_is_sized(*v) => + match (self_ty.kind(), unsize_ty.kind()) { + (&ty::Infer(ty::TyVar(v)), ty::Dynamic(..)) + if self.type_var_is_sized(v) => { debug!("coerce_unsized: have sized infer {:?}", v); coercion.obligations.push(obligation); diff --git a/compiler/rustc_hir_typeck/src/demand.rs b/compiler/rustc_hir_typeck/src/demand.rs index f65f16e317d49..06e857ec3ca1d 100644 --- a/compiler/rustc_hir_typeck/src/demand.rs +++ b/compiler/rustc_hir_typeck/src/demand.rs @@ -1480,7 +1480,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // For this suggestion to make sense, the type would need to be `Copy`, // or we have to be moving out of a `Box` - if self.type_is_copy_modulo_regions(self.param_env, expected, sp) + if self.type_is_copy_modulo_regions(self.param_env, expected) // FIXME(compiler-errors): We can actually do this if the checked_ty is // `steps` layers of boxes, not just one, but this is easier and most likely. || (checked_ty.is_box() && steps == 1) diff --git a/compiler/rustc_hir_typeck/src/expr_use_visitor.rs b/compiler/rustc_hir_typeck/src/expr_use_visitor.rs index 9aa6c7f103f87..c62c1553d6f72 100644 --- a/compiler/rustc_hir_typeck/src/expr_use_visitor.rs +++ b/compiler/rustc_hir_typeck/src/expr_use_visitor.rs @@ -867,10 +867,7 @@ fn copy_or_move<'a, 'tcx>( mc: &mc::MemCategorizationContext<'a, 'tcx>, place_with_id: &PlaceWithHirId<'tcx>, ) -> ConsumeMode { - if !mc.type_is_copy_modulo_regions( - place_with_id.place.ty(), - mc.tcx().hir().span(place_with_id.hir_id), - ) { + if !mc.type_is_copy_modulo_regions(place_with_id.place.ty()) { ConsumeMode::Move } else { ConsumeMode::Copy diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs index 7a09ea40d7974..7273b93b67690 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs @@ -1011,11 +1011,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { let mut suggest_copied_or_cloned = || { let expr_inner_ty = substs.type_at(0); let expected_inner_ty = expected_substs.type_at(0); - if let ty::Ref(_, ty, hir::Mutability::Not) = expr_inner_ty.kind() - && self.can_eq(self.param_env, *ty, expected_inner_ty) + if let &ty::Ref(_, ty, hir::Mutability::Not) = expr_inner_ty.kind() + && self.can_eq(self.param_env, ty, expected_inner_ty) { let def_path = self.tcx.def_path_str(adt_def.did()); - if self.type_is_copy_modulo_regions(self.param_env, *ty, expr.span) { + if self.type_is_copy_modulo_regions(self.param_env, ty) { diag.span_suggestion_verbose( expr.span.shrink_to_hi(), format!( @@ -1029,9 +1029,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { && rustc_trait_selection::traits::type_known_to_meet_bound_modulo_regions( self, self.param_env, - *ty, + ty, clone_did, - expr.span ) { diag.span_suggestion_verbose( diff --git a/compiler/rustc_hir_typeck/src/mem_categorization.rs b/compiler/rustc_hir_typeck/src/mem_categorization.rs index 9a8d7ca9e3382..95e5483abf3bd 100644 --- a/compiler/rustc_hir_typeck/src/mem_categorization.rs +++ b/compiler/rustc_hir_typeck/src/mem_categorization.rs @@ -120,8 +120,8 @@ impl<'a, 'tcx> MemCategorizationContext<'a, 'tcx> { self.infcx.tcx } - pub(crate) fn type_is_copy_modulo_regions(&self, ty: Ty<'tcx>, span: Span) -> bool { - self.infcx.type_is_copy_modulo_regions(self.param_env, ty, span) + pub(crate) fn type_is_copy_modulo_regions(&self, ty: Ty<'tcx>) -> bool { + self.infcx.type_is_copy_modulo_regions(self.param_env, ty) } fn resolve_vars_if_possible(&self, value: T) -> T diff --git a/compiler/rustc_hir_typeck/src/op.rs b/compiler/rustc_hir_typeck/src/op.rs index 37783bc91bb8c..8a83bb58573d3 100644 --- a/compiler/rustc_hir_typeck/src/op.rs +++ b/compiler/rustc_hir_typeck/src/op.rs @@ -21,7 +21,7 @@ use rustc_span::symbol::{sym, Ident}; use rustc_span::Span; use rustc_trait_selection::infer::InferCtxtExt; use rustc_trait_selection::traits::error_reporting::suggestions::TypeErrCtxtExt as _; -use rustc_trait_selection::traits::{self, FulfillmentError}; +use rustc_trait_selection::traits::{self, FulfillmentError, ObligationCtxt}; use rustc_type_ir::sty::TyKind::*; impl<'a, 'tcx> FnCtxt<'a, 'tcx> { @@ -434,7 +434,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { if self.type_is_copy_modulo_regions( self.param_env, *lhs_deref_ty, - lhs_expr.span, ) { suggest_deref_binop(*lhs_deref_ty); } @@ -776,7 +775,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { (None, Some(trait_did)) => { let (obligation, _) = self.obligation_for_method(cause, trait_did, lhs_ty, Some(input_types)); - Err(rustc_trait_selection::traits::fully_solve_obligation(self, obligation)) + // FIXME: This should potentially just add the obligation to the `FnCtxt` + let ocx = ObligationCtxt::new(&self.infcx); + ocx.register_obligation(obligation); + Err(ocx.select_all_or_error()) } } } diff --git a/compiler/rustc_hir_typeck/src/upvar.rs b/compiler/rustc_hir_typeck/src/upvar.rs index 4a432328c4d1b..84fe21825d787 100644 --- a/compiler/rustc_hir_typeck/src/upvar.rs +++ b/compiler/rustc_hir_typeck/src/upvar.rs @@ -424,7 +424,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // closures. We want to make sure any adjustment that might make us move the place into // the closure gets handled. let (place, capture_kind) = - restrict_precision_for_drop_types(self, place, capture_kind, usage_span); + restrict_precision_for_drop_types(self, place, capture_kind); capture_info.capture_kind = capture_kind; (place, capture_info) @@ -1822,9 +1822,8 @@ fn restrict_precision_for_drop_types<'a, 'tcx>( fcx: &'a FnCtxt<'a, 'tcx>, mut place: Place<'tcx>, mut curr_mode: ty::UpvarCapture, - span: Span, ) -> (Place<'tcx>, ty::UpvarCapture) { - let is_copy_type = fcx.infcx.type_is_copy_modulo_regions(fcx.param_env, place.ty(), span); + let is_copy_type = fcx.infcx.type_is_copy_modulo_regions(fcx.param_env, place.ty()); if let (false, UpvarCapture::ByValue) = (is_copy_type, curr_mode) { for i in 0..place.projections.len() { diff --git a/compiler/rustc_lint/src/for_loops_over_fallibles.rs b/compiler/rustc_lint/src/for_loops_over_fallibles.rs index a3367ae4a9f15..cb7711034ed63 100644 --- a/compiler/rustc_lint/src/for_loops_over_fallibles.rs +++ b/compiler/rustc_lint/src/for_loops_over_fallibles.rs @@ -11,6 +11,7 @@ use rustc_hir as hir; use rustc_infer::{infer::TyCtxtInferExt, traits::ObligationCause}; use rustc_middle::ty::{self, List}; use rustc_span::{sym, Span}; +use rustc_trait_selection::traits::ObligationCtxt; declare_lint! { /// The `for_loops_over_fallibles` lint checks for `for` loops over `Option` or `Result` values. @@ -136,20 +137,23 @@ fn suggest_question_mark<'tcx>( let ty = substs.type_at(0); let infcx = cx.tcx.infer_ctxt().build(); + let ocx = ObligationCtxt::new(&infcx); + let body_def_id = cx.tcx.hir().body_owner_def_id(body_id); let cause = ObligationCause::new( span, body_def_id, rustc_infer::traits::ObligationCauseCode::MiscObligation, ); - let errors = rustc_trait_selection::traits::fully_solve_bound( - &infcx, + + ocx.register_bound( cause, + // FIXME: using the empty param env is wrong, should use the one from `body_id`. ty::ParamEnv::empty(), // Erase any region vids from the type, which may not be resolved infcx.tcx.erase_regions(ty), into_iterator_did, ); - errors.is_empty() + ocx.select_all_or_error().is_empty() } diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs index 298b2c3073cd3..6ba3ab097de53 100644 --- a/compiler/rustc_middle/src/ty/mod.rs +++ b/compiler/rustc_middle/src/ty/mod.rs @@ -1128,6 +1128,13 @@ impl<'tcx, T> ToPredicate<'tcx, T> for T { } } +impl<'tcx> ToPredicate<'tcx> for PredicateKind<'tcx> { + #[inline(always)] + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { + ty::Binder::dummy(self).to_predicate(tcx) + } +} + impl<'tcx> ToPredicate<'tcx> for Binder<'tcx, PredicateKind<'tcx>> { #[inline(always)] fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { @@ -1142,6 +1149,13 @@ impl<'tcx> ToPredicate<'tcx> for Clause<'tcx> { } } +impl<'tcx> ToPredicate<'tcx> for TraitRef<'tcx> { + #[inline(always)] + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { + ty::Binder::dummy(self).to_predicate(tcx) + } +} + impl<'tcx> ToPredicate<'tcx> for Binder<'tcx, TraitRef<'tcx>> { #[inline(always)] fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { diff --git a/compiler/rustc_mir_build/src/build/misc.rs b/compiler/rustc_mir_build/src/build/misc.rs index baeb2718cae46..90d78658f9683 100644 --- a/compiler/rustc_mir_build/src/build/misc.rs +++ b/compiler/rustc_mir_build/src/build/misc.rs @@ -5,7 +5,7 @@ use crate::build::Builder; use rustc_middle::mir::*; use rustc_middle::ty::{self, Ty}; -use rustc_span::{Span, DUMMY_SP}; +use rustc_span::Span; use rustc_trait_selection::infer::InferCtxtExt; impl<'a, 'tcx> Builder<'a, 'tcx> { @@ -66,7 +66,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { pub(crate) fn consume_by_copy_or_move(&self, place: Place<'tcx>) -> Operand<'tcx> { let tcx = self.tcx; let ty = place.ty(&self.local_decls, tcx).ty; - if !self.infcx.type_is_copy_modulo_regions(self.param_env, ty, DUMMY_SP) { + if !self.infcx.type_is_copy_modulo_regions(self.param_env, ty) { Operand::Move(place) } else { Operand::Copy(place) 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 ff88d00135173..274c2f06137a3 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 @@ -1,14 +1,14 @@ use rustc_hir as hir; use rustc_index::vec::Idx; use rustc_infer::infer::{InferCtxt, TyCtxtInferExt}; +use rustc_infer::traits::Obligation; use rustc_middle::mir::{self, Field}; use rustc_middle::thir::{FieldPat, Pat, PatKind}; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_session::lint; use rustc_span::Span; -use rustc_trait_selection::traits::predicate_for_trait_def; use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt; -use rustc_trait_selection::traits::{self, ObligationCause, PredicateObligation}; +use rustc_trait_selection::traits::{self, ObligationCause}; use std::cell::Cell; @@ -189,17 +189,15 @@ impl<'tcx> ConstToPat<'tcx> { // using `PartialEq::eq` in this scenario in the past.) let partial_eq_trait_id = self.tcx().require_lang_item(hir::LangItem::PartialEq, Some(self.span)); - let obligation: PredicateObligation<'_> = predicate_for_trait_def( + let partial_eq_obligation = Obligation::new( self.tcx(), + ObligationCause::dummy(), self.param_env, - ObligationCause::misc(self.span, self.id.owner.def_id), - partial_eq_trait_id, - 0, - [ty, ty], + self.tcx().mk_trait_ref(partial_eq_trait_id, [ty, ty]), ); - // FIXME: should this call a `predicate_must_hold` variant instead? - let has_impl = self.infcx.predicate_may_hold(&obligation); + // FIXME: should this call a `predicate_must_hold` variant instead? + let has_impl = self.infcx.predicate_may_hold(&partial_eq_obligation); // Note: To fix rust-lang/rust#65466, we could just remove this type // walk hack for function pointers, and unconditionally error diff --git a/compiler/rustc_trait_selection/src/infer.rs b/compiler/rustc_trait_selection/src/infer.rs index 9b47c7299bb7b..911cc0b88c406 100644 --- a/compiler/rustc_trait_selection/src/infer.rs +++ b/compiler/rustc_trait_selection/src/infer.rs @@ -8,26 +8,16 @@ use rustc_middle::infer::canonical::{Canonical, CanonicalQueryResponse, QueryRes use rustc_middle::traits::query::Fallible; use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeVisitableExt}; use rustc_middle::ty::{GenericArg, ToPredicate}; -use rustc_span::{Span, DUMMY_SP}; +use rustc_span::DUMMY_SP; use std::fmt::Debug; pub use rustc_infer::infer::*; pub trait InferCtxtExt<'tcx> { - fn type_is_copy_modulo_regions( - &self, - param_env: ty::ParamEnv<'tcx>, - ty: Ty<'tcx>, - span: Span, - ) -> bool; + fn type_is_copy_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool; - fn type_is_sized_modulo_regions( - &self, - param_env: ty::ParamEnv<'tcx>, - ty: Ty<'tcx>, - span: Span, - ) -> bool; + fn type_is_sized_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool; /// Check whether a `ty` implements given trait(trait_def_id). /// The inputs are: @@ -46,13 +36,9 @@ pub trait InferCtxtExt<'tcx> { param_env: ty::ParamEnv<'tcx>, ) -> traits::EvaluationResult; } + impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> { - fn type_is_copy_modulo_regions( - &self, - param_env: ty::ParamEnv<'tcx>, - ty: Ty<'tcx>, - span: Span, - ) -> bool { + fn type_is_copy_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool { let ty = self.resolve_vars_if_possible(ty); if !(param_env, ty).needs_infer() { @@ -65,17 +51,12 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> { // rightly refuses to work with inference variables, but // moves_by_default has a cache, which we want to use in other // cases. - traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, copy_def_id, span) + traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, copy_def_id) } - fn type_is_sized_modulo_regions( - &self, - param_env: ty::ParamEnv<'tcx>, - ty: Ty<'tcx>, - span: Span, - ) -> bool { + fn type_is_sized_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool { let lang_item = self.tcx.require_lang_item(LangItem::Sized, None); - traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, lang_item, span) + traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, lang_item) } #[instrument(level = "debug", skip(self, params), ret)] diff --git a/compiler/rustc_trait_selection/src/traits/auto_trait.rs b/compiler/rustc_trait_selection/src/traits/auto_trait.rs index 1870d3a2daf32..dbf6775afc2fc 100644 --- a/compiler/rustc_trait_selection/src/traits/auto_trait.rs +++ b/compiler/rustc_trait_selection/src/traits/auto_trait.rs @@ -180,8 +180,9 @@ impl<'tcx> AutoTraitFinder<'tcx> { // At this point, we already have all of the bounds we need. FulfillmentContext is used // to store all of the necessary region/lifetime bounds in the InferContext, as well as // an additional sanity check. - let errors = - super::fully_solve_bound(&infcx, ObligationCause::dummy(), full_env, ty, trait_did); + let ocx = ObligationCtxt::new(&infcx); + ocx.register_bound(ObligationCause::dummy(), full_env, ty, trait_did); + let errors = ocx.select_all_or_error(); if !errors.is_empty() { panic!("Unable to fulfill trait {:?} for '{:?}': {:?}", trait_did, ty, errors); } diff --git a/compiler/rustc_trait_selection/src/traits/coherence.rs b/compiler/rustc_trait_selection/src/traits/coherence.rs index f4cfe4ec0b0ce..572d20b5368b4 100644 --- a/compiler/rustc_trait_selection/src/traits/coherence.rs +++ b/compiler/rustc_trait_selection/src/traits/coherence.rs @@ -383,7 +383,10 @@ fn resolve_negative_obligation<'tcx>( }; let param_env = o.param_env; - if !super::fully_solve_obligation(&infcx, o).is_empty() { + let ocx = ObligationCtxt::new(&infcx); + ocx.register_obligation(o); + let errors = ocx.select_all_or_error(); + if !errors.is_empty() { return false; } diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs index bfeda88a6d40c..b27a39290781a 100644 --- a/compiler/rustc_trait_selection/src/traits/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/mod.rs @@ -30,7 +30,7 @@ use rustc_middle::ty::fold::TypeFoldable; use rustc_middle::ty::visit::{TypeVisitable, TypeVisitableExt}; use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, TypeSuperVisitable}; use rustc_middle::ty::{InternalSubsts, SubstsRef}; -use rustc_span::def_id::{DefId, CRATE_DEF_ID}; +use rustc_span::def_id::DefId; use rustc_span::Span; use std::fmt::Debug; @@ -63,9 +63,7 @@ pub use self::util::{ elaborate_trait_ref, elaborate_trait_refs, }; pub use self::util::{expand_trait_aliases, TraitAliasExpander}; -pub use self::util::{ - get_vtable_index_of_object_method, impl_item_is_final, predicate_for_trait_def, upcast_choices, -}; +pub use self::util::{get_vtable_index_of_object_method, impl_item_is_final, upcast_choices}; pub use self::util::{ supertrait_def_ids, supertraits, transitive_bounds, transitive_bounds_that_define_assoc_type, SupertraitDefIds, Supertraits, @@ -131,29 +129,23 @@ pub fn type_known_to_meet_bound_modulo_regions<'tcx>( param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>, def_id: DefId, - span: Span, ) -> bool { let trait_ref = ty::Binder::dummy(infcx.tcx.mk_trait_ref(def_id, [ty])); - pred_known_to_hold_modulo_regions(infcx, param_env, trait_ref.without_const(), span) + pred_known_to_hold_modulo_regions(infcx, param_env, trait_ref.without_const()) } -#[instrument(level = "debug", skip(infcx, param_env, span, pred), ret)] +/// FIXME(@lcnr): this function doesn't seem right and shouldn't exist? +/// +/// Ping me on zulip if you want to use this method and need help with finding +/// an appropriate replacement. +#[instrument(level = "debug", skip(infcx, param_env, pred), ret)] fn pred_known_to_hold_modulo_regions<'tcx>( infcx: &InferCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, pred: impl ToPredicate<'tcx> + TypeVisitable>, - span: Span, ) -> bool { let has_non_region_infer = pred.has_non_region_infer(); - let obligation = Obligation { - param_env, - // We can use a dummy node-id here because we won't pay any mind - // to region obligations that arise (there shouldn't really be any - // anyhow). - cause: ObligationCause::misc(span, CRATE_DEF_ID), - recursion_depth: 0, - predicate: pred.to_predicate(infcx.tcx), - }; + let obligation = Obligation::new(infcx.tcx, ObligationCause::dummy(), param_env, pred); let result = infcx.evaluate_obligation_no_overflow(&obligation); debug!(?result); @@ -166,14 +158,13 @@ fn pred_known_to_hold_modulo_regions<'tcx>( // this function's result remains infallible, we must confirm // that guess. While imperfect, I believe this is sound. - // FIXME(@lcnr): this function doesn't seem right. - // // The handling of regions in this area of the code is terrible, // see issue #29149. We should be able to improve on this with // NLL. - let errors = fully_solve_obligation(infcx, obligation); - - match &errors[..] { + let ocx = ObligationCtxt::new(infcx); + ocx.register_obligation(obligation); + let errors = ocx.select_all_or_error(); + match errors.as_slice() { [] => true, errors => { debug!(?errors); @@ -389,43 +380,6 @@ where Ok(resolved_value) } -/// Process an obligation (and any nested obligations that come from it) to -/// completion, returning any errors -pub fn fully_solve_obligation<'tcx>( - infcx: &InferCtxt<'tcx>, - obligation: PredicateObligation<'tcx>, -) -> Vec> { - fully_solve_obligations(infcx, [obligation]) -} - -/// Process a set of obligations (and any nested obligations that come from them) -/// to completion -pub fn fully_solve_obligations<'tcx>( - infcx: &InferCtxt<'tcx>, - obligations: impl IntoIterator>, -) -> Vec> { - let ocx = ObligationCtxt::new(infcx); - ocx.register_obligations(obligations); - ocx.select_all_or_error() -} - -/// Process a bound (and any nested obligations that come from it) to completion. -/// This is a convenience function for traits that have no generic arguments, such -/// as auto traits, and builtin traits like Copy or Sized. -pub fn fully_solve_bound<'tcx>( - infcx: &InferCtxt<'tcx>, - cause: ObligationCause<'tcx>, - param_env: ty::ParamEnv<'tcx>, - ty: Ty<'tcx>, - bound: DefId, -) -> Vec> { - let tcx = infcx.tcx; - let trait_ref = tcx.mk_trait_ref(bound, [ty]); - let obligation = Obligation::new(tcx, cause, param_env, ty::Binder::dummy(trait_ref)); - - fully_solve_obligation(infcx, obligation) -} - /// Normalizes the predicates and checks whether they hold in an empty environment. If this /// returns true, then either normalize encountered an error or one of the predicates did not /// hold. Used when creating vtables to check for unsatisfiable methods. diff --git a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs index 6cb64ad574f5b..bac02f2d38328 100644 --- a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs +++ b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs @@ -1,7 +1,7 @@ use crate::infer::InferCtxt; use crate::traits::query::type_op::{self, TypeOp, TypeOpOutput}; use crate::traits::query::NoSolution; -use crate::traits::ObligationCause; +use crate::traits::{ObligationCause, ObligationCtxt}; use rustc_data_structures::fx::FxIndexSet; use rustc_middle::ty::{self, ParamEnv, Ty}; use rustc_span::def_id::LocalDefId; @@ -71,22 +71,23 @@ impl<'a, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'tcx> { if let Some(constraints) = constraints { debug!(?constraints); + if !constraints.member_constraints.is_empty() { + span_bug!(span, "{:#?}", constraints.member_constraints); + } + // Instantiation may have produced new inference variables and constraints on those // variables. Process these constraints. + let ocx = ObligationCtxt::new(self); let cause = ObligationCause::misc(span, body_id); - let errors = super::fully_solve_obligations( - self, - constraints.outlives.iter().map(|constraint| { - self.query_outlives_constraint_to_obligation( - *constraint, - cause.clone(), - param_env, - ) - }), - ); - if !constraints.member_constraints.is_empty() { - span_bug!(span, "{:#?}", constraints.member_constraints); + for &constraint in &constraints.outlives { + ocx.register_obligation(self.query_outlives_constraint_to_obligation( + constraint, + cause.clone(), + param_env, + )); } + + let errors = ocx.select_all_or_error(); if !errors.is_empty() { self.tcx.sess.delay_span_bug( span, diff --git a/compiler/rustc_trait_selection/src/traits/query/type_op/custom.rs b/compiler/rustc_trait_selection/src/traits/query/type_op/custom.rs index 6bf3ed0d0e29a..8f1b05c1190d5 100644 --- a/compiler/rustc_trait_selection/src/traits/query/type_op/custom.rs +++ b/compiler/rustc_trait_selection/src/traits/query/type_op/custom.rs @@ -1,8 +1,8 @@ use crate::infer::canonical::query_response; use crate::infer::{InferCtxt, InferOk}; -use crate::traits; use crate::traits::query::type_op::TypeOpOutput; use crate::traits::query::Fallible; +use crate::traits::ObligationCtxt; use rustc_infer::infer::region_constraints::RegionConstraintData; use rustc_span::source_map::DUMMY_SP; @@ -73,7 +73,9 @@ pub fn scrape_region_constraints<'tcx, Op: super::TypeOp<'tcx, Output = R>, R>( ); let InferOk { value, obligations } = infcx.commit_if_ok(|_| op())?; - let errors = traits::fully_solve_obligations(infcx, obligations); + let ocx = ObligationCtxt::new(infcx); + ocx.register_obligations(obligations); + let errors = ocx.select_all_or_error(); if !errors.is_empty() { infcx.tcx.sess.diagnostic().delay_span_bug( DUMMY_SP, @@ -82,9 +84,7 @@ pub fn scrape_region_constraints<'tcx, Op: super::TypeOp<'tcx, Output = R>, R>( } let region_obligations = infcx.take_registered_region_obligations(); - let region_constraint_data = infcx.take_and_reset_region_constraints(); - let region_constraints = query_response::make_query_region_constraints( infcx.tcx, region_obligations diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs index 3d5dd18f4c1d7..eb354bc3f50c6 100644 --- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs +++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs @@ -18,7 +18,7 @@ use rustc_session::config::TraitSolver; use rustc_span::def_id::DefId; use crate::traits::project::{normalize_with_depth, normalize_with_depth_to}; -use crate::traits::util::{self, closure_trait_ref_and_return_type, predicate_for_trait_def}; +use crate::traits::util::{self, closure_trait_ref_and_return_type}; use crate::traits::vtable::{ count_own_vtable_entries, prepare_vtable_segments, vtable_trait_first_method_offset, VtblSegment, @@ -253,15 +253,13 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { }; let cause = obligation.derived_cause(BuiltinDerivedObligation); - ensure_sufficient_stack(|| { - self.collect_predicates_for_types( - obligation.param_env, - cause, - obligation.recursion_depth + 1, - trait_def, - nested, - ) - }) + self.collect_predicates_for_types( + obligation.param_env, + cause, + obligation.recursion_depth + 1, + trait_def, + nested, + ) } else { vec![] }; @@ -1118,14 +1116,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { nested.extend(obligations); // Construct the nested `TailField: Unsize>` predicate. - nested.push(predicate_for_trait_def( + let tail_unsize_obligation = obligation.with( tcx, - obligation.param_env, - obligation.cause.clone(), - obligation.predicate.def_id(), - obligation.recursion_depth + 1, - [source_tail, target_tail], - )); + tcx.mk_trait_ref(obligation.predicate.def_id(), [source_tail, target_tail]), + ); + nested.push(tail_unsize_obligation); } // `(.., T)` -> `(.., U)` @@ -1147,17 +1142,10 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { .map_err(|_| Unimplemented)?; nested.extend(obligations); - // Construct the nested `T: Unsize` predicate. - nested.push(ensure_sufficient_stack(|| { - predicate_for_trait_def( - tcx, - obligation.param_env, - obligation.cause.clone(), - obligation.predicate.def_id(), - obligation.recursion_depth + 1, - [a_last, b_last], - ) - })); + // Add a nested `T: Unsize` predicate. + let last_unsize_obligation = obligation + .with(tcx, tcx.mk_trait_ref(obligation.predicate.def_id(), [a_last, b_last])); + nested.push(last_unsize_obligation); } _ => bug!("source: {source}, target: {target}"), diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index bc1c72da1e175..d9b2b7dbe1645 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -17,7 +17,7 @@ use super::project; use super::project::normalize_with_depth_to; use super::project::ProjectionTyObligation; use super::util; -use super::util::{closure_trait_ref_and_return_type, predicate_for_trait_def}; +use super::util::closure_trait_ref_and_return_type; use super::wf; use super::{ ErrorReporting, ImplDerivedObligation, ImplDerivedObligationCause, Normalized, Obligation, @@ -2440,15 +2440,14 @@ impl<'tcx> SelectionContext<'_, 'tcx> { placeholder_ty, ) }); - let placeholder_obligation = predicate_for_trait_def( + + let obligation = Obligation::new( self.tcx(), - param_env, cause.clone(), - trait_def_id, - recursion_depth, - [normalized_ty], + param_env, + self.tcx().mk_trait_ref(trait_def_id, [normalized_ty]), ); - obligations.push(placeholder_obligation); + obligations.push(obligation); obligations }) .collect() diff --git a/compiler/rustc_trait_selection/src/traits/util.rs b/compiler/rustc_trait_selection/src/traits/util.rs index ab4c36975a0ec..00c9a35225881 100644 --- a/compiler/rustc_trait_selection/src/traits/util.rs +++ b/compiler/rustc_trait_selection/src/traits/util.rs @@ -1,11 +1,11 @@ use super::NormalizeExt; -use super::{Obligation, ObligationCause, PredicateObligation, SelectionContext}; +use super::{ObligationCause, PredicateObligation, SelectionContext}; use rustc_data_structures::fx::FxHashSet; use rustc_errors::Diagnostic; use rustc_hir::def_id::DefId; use rustc_infer::infer::InferOk; +use rustc_middle::ty::SubstsRef; use rustc_middle::ty::{self, ImplSubject, ToPredicate, Ty, TyCtxt, TypeVisitableExt}; -use rustc_middle::ty::{GenericArg, SubstsRef}; use rustc_span::Span; use smallvec::SmallVec; @@ -218,33 +218,6 @@ pub fn impl_subject_and_oblig<'a, 'tcx>( (subject, impl_obligations) } -pub fn predicate_for_trait_ref<'tcx>( - tcx: TyCtxt<'tcx>, - cause: ObligationCause<'tcx>, - param_env: ty::ParamEnv<'tcx>, - trait_ref: ty::TraitRef<'tcx>, - recursion_depth: usize, -) -> PredicateObligation<'tcx> { - Obligation { - cause, - param_env, - recursion_depth, - predicate: ty::Binder::dummy(trait_ref).without_const().to_predicate(tcx), - } -} - -pub fn predicate_for_trait_def<'tcx>( - tcx: TyCtxt<'tcx>, - param_env: ty::ParamEnv<'tcx>, - cause: ObligationCause<'tcx>, - trait_def_id: DefId, - recursion_depth: usize, - params: impl IntoIterator>>, -) -> PredicateObligation<'tcx> { - let trait_ref = tcx.mk_trait_ref(trait_def_id, params); - predicate_for_trait_ref(tcx, cause, param_env, trait_ref, recursion_depth) -} - /// Casts a trait reference into a reference to one of its super /// traits; returns `None` if `target_trait_def_id` is not a /// supertrait. diff --git a/compiler/rustc_ty_utils/src/common_traits.rs b/compiler/rustc_ty_utils/src/common_traits.rs index d3169b6d962ec..3b1abdcb24f8f 100644 --- a/compiler/rustc_ty_utils/src/common_traits.rs +++ b/compiler/rustc_ty_utils/src/common_traits.rs @@ -3,7 +3,6 @@ use rustc_hir::lang_items::LangItem; use rustc_infer::infer::TyCtxtInferExt; use rustc_middle::ty::{self, Ty, TyCtxt}; -use rustc_span::DUMMY_SP; use rustc_trait_selection::traits; fn is_copy_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool { @@ -30,7 +29,7 @@ fn is_item_raw<'tcx>( let (param_env, ty) = query.into_parts(); let trait_def_id = tcx.require_lang_item(item, None); let infcx = tcx.infer_ctxt().build(); - traits::type_known_to_meet_bound_modulo_regions(&infcx, param_env, ty, trait_def_id, DUMMY_SP) + traits::type_known_to_meet_bound_modulo_regions(&infcx, param_env, ty, trait_def_id) } pub(crate) fn provide(providers: &mut ty::query::Providers) { diff --git a/src/tools/clippy/clippy_lints/src/future_not_send.rs b/src/tools/clippy/clippy_lints/src/future_not_send.rs index 9fb73a371b8f4..ed0bd58c770c7 100644 --- a/src/tools/clippy/clippy_lints/src/future_not_send.rs +++ b/src/tools/clippy/clippy_lints/src/future_not_send.rs @@ -9,7 +9,7 @@ use rustc_session::{declare_lint_pass, declare_tool_lint}; use rustc_span::def_id::LocalDefId; use rustc_span::{sym, Span}; use rustc_trait_selection::traits::error_reporting::suggestions::TypeErrCtxtExt; -use rustc_trait_selection::traits::{self, FulfillmentError}; +use rustc_trait_selection::traits::{self, FulfillmentError, ObligationCtxt}; declare_clippy_lint! { /// ### What it does @@ -79,8 +79,10 @@ impl<'tcx> LateLintPass<'tcx> for FutureNotSend { let send_trait = cx.tcx.get_diagnostic_item(sym::Send).unwrap(); let span = decl.output.span(); let infcx = cx.tcx.infer_ctxt().build(); + let ocx = ObligationCtxt::new(&infcx); let cause = traits::ObligationCause::misc(span, fn_def_id); - let send_errors = traits::fully_solve_bound(&infcx, cause, cx.param_env, ret_ty, send_trait); + ocx.register_bound(cause, cx.param_env, ret_ty, send_trait); + let send_errors = ocx.select_all_or_error(); if !send_errors.is_empty() { span_lint_and_then( cx, From c63861b9d5a91b827c5c8164e24ee556dd790bbe Mon Sep 17 00:00:00 2001 From: lcnr Date: Tue, 14 Mar 2023 14:56:16 +0100 Subject: [PATCH 2/3] evaluate: improve and fix recursion depth handling --- compiler/rustc_infer/src/traits/mod.rs | 10 +++ .../src/traits/select/mod.rs | 71 +++++-------------- tests/ui/associated-consts/issue-93775.rs | 2 +- tests/ui/did_you_mean/recursion_limit.stderr | 7 +- tests/ui/error-codes/E0275.stderr | 2 +- tests/ui/issues/issue-20413.stderr | 34 ++++----- tests/ui/traits/cycle-cache-err-60010.stderr | 15 +--- .../traits/issue-91949-hangs-on-recursion.rs | 2 +- .../issue-91949-hangs-on-recursion.stderr | 12 +++- 9 files changed, 60 insertions(+), 95 deletions(-) diff --git a/compiler/rustc_infer/src/traits/mod.rs b/compiler/rustc_infer/src/traits/mod.rs index 77c67c14ecc55..dd9b2e548c731 100644 --- a/compiler/rustc_infer/src/traits/mod.rs +++ b/compiler/rustc_infer/src/traits/mod.rs @@ -8,6 +8,8 @@ mod project; mod structural_impls; pub mod util; +use std::cmp; + use hir::def_id::LocalDefId; use rustc_hir as hir; use rustc_middle::ty::error::{ExpectedFound, TypeError}; @@ -139,6 +141,14 @@ impl<'tcx, O> Obligation<'tcx, O> { Self::with_depth(tcx, cause, 0, param_env, predicate) } + /// We often create nested obligations without setting the correct depth. + /// + /// To deal with this evaluate and fulfill explicitly update the depth + /// of nested obligations using this function. + pub fn set_depth_from_parent(&mut self, parent_depth: usize) { + self.recursion_depth = cmp::max(parent_depth + 1, self.recursion_depth); + } + pub fn with_depth( tcx: TyCtxt<'tcx>, cause: ObligationCause<'tcx>, diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index d9b2b7dbe1645..b8758ad93231d 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -595,7 +595,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { self.evaluate_predicates_recursively_in_new_solver(predicates) } else { let mut result = EvaluatedToOk; - for obligation in predicates { + for mut obligation in predicates { + obligation.set_depth_from_parent(stack.depth()); let eval = self.evaluate_predicate_recursively(stack, obligation.clone())?; if let EvaluatedToErr = eval { // fast-path - EvaluatedToErr is the top of the lattice, @@ -661,12 +662,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let p = bound_predicate.rebind(p); // Does this code ever run? match self.infcx.subtype_predicate(&obligation.cause, obligation.param_env, p) { - Ok(Ok(InferOk { mut obligations, .. })) => { - self.add_depth(obligations.iter_mut(), obligation.recursion_depth); - self.evaluate_predicates_recursively( - previous_stack, - obligations.into_iter(), - ) + Ok(Ok(InferOk { obligations, .. })) => { + self.evaluate_predicates_recursively(previous_stack, obligations) } Ok(Err(_)) => Ok(EvaluatedToErr), Err(..) => Ok(EvaluatedToAmbig), @@ -677,12 +674,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let p = bound_predicate.rebind(p); // Does this code ever run? match self.infcx.coerce_predicate(&obligation.cause, obligation.param_env, p) { - Ok(Ok(InferOk { mut obligations, .. })) => { - self.add_depth(obligations.iter_mut(), obligation.recursion_depth); - self.evaluate_predicates_recursively( - previous_stack, - obligations.into_iter(), - ) + Ok(Ok(InferOk { obligations, .. })) => { + self.evaluate_predicates_recursively(previous_stack, obligations) } Ok(Err(_)) => Ok(EvaluatedToErr), Err(..) => Ok(EvaluatedToAmbig), @@ -755,9 +748,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { arg, obligation.cause.span, ) { - Some(mut obligations) => { - self.add_depth(obligations.iter_mut(), obligation.recursion_depth); - + Some(obligations) => { cache.wf_args.borrow_mut().push((arg, previous_stack.depth())); let result = self.evaluate_predicates_recursively(previous_stack, obligations); @@ -826,10 +817,14 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { } } - self.add_depth( - subobligations.iter_mut(), - obligation.recursion_depth, - ); + // Need to explicitly set the depth of nested goals here as + // projection obligations can cycle by themselves and in + // `evaluate_predicates_recursively` we only add the depth + // for parent trait goals because only these get added to the + // `TraitObligationStackList`. + for subobligation in subobligations.iter_mut() { + subobligation.set_depth_from_parent(obligation.recursion_depth); + } let res = self.evaluate_predicates_recursively( previous_stack, subobligations, @@ -909,38 +904,28 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { if a.def.did == b.def.did && tcx.def_kind(a.def.did) == DefKind::AssocConst => { - if let Ok(new_obligations) = self + if let Ok(InferOk { obligations, value: () }) = self .infcx .at(&obligation.cause, obligation.param_env) .trace(c1, c2) .eq(DefineOpaqueTypes::No, a.substs, b.substs) { - let mut obligations = new_obligations.obligations; - self.add_depth( - obligations.iter_mut(), - obligation.recursion_depth, - ); return self.evaluate_predicates_recursively( previous_stack, - obligations.into_iter(), + obligations, ); } } (_, Unevaluated(_)) | (Unevaluated(_), _) => (), (_, _) => { - if let Ok(new_obligations) = self + if let Ok(InferOk { obligations, value: () }) = self .infcx .at(&obligation.cause, obligation.param_env) .eq(DefineOpaqueTypes::No, c1, c2) { - let mut obligations = new_obligations.obligations; - self.add_depth( - obligations.iter_mut(), - obligation.recursion_depth, - ); return self.evaluate_predicates_recursively( previous_stack, - obligations.into_iter(), + obligations, ); } } @@ -1366,24 +1351,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { self.infcx.evaluation_cache.insert((param_env, trait_pred), dep_node, result); } - /// For various reasons, it's possible for a subobligation - /// to have a *lower* recursion_depth than the obligation used to create it. - /// Projection sub-obligations may be returned from the projection cache, - /// which results in obligations with an 'old' `recursion_depth`. - /// Additionally, methods like `InferCtxt.subtype_predicate` produce - /// subobligations without taking in a 'parent' depth, causing the - /// generated subobligations to have a `recursion_depth` of `0`. - /// - /// To ensure that obligation_depth never decreases, we force all subobligations - /// to have at least the depth of the original obligation. - fn add_depth>>( - &self, - it: I, - min_depth: usize, - ) { - it.for_each(|o| o.recursion_depth = cmp::max(min_depth, o.recursion_depth) + 1); - } - fn check_recursion_depth( &self, depth: usize, diff --git a/tests/ui/associated-consts/issue-93775.rs b/tests/ui/associated-consts/issue-93775.rs index 7a007b732de8e..db788fe6e6af1 100644 --- a/tests/ui/associated-consts/issue-93775.rs +++ b/tests/ui/associated-consts/issue-93775.rs @@ -3,7 +3,7 @@ // Regression for #93775, needs build-pass to test it. -#![recursion_limit = "1000"] +#![recursion_limit = "1001"] use std::marker::PhantomData; diff --git a/tests/ui/did_you_mean/recursion_limit.stderr b/tests/ui/did_you_mean/recursion_limit.stderr index 247fe4b5b07bd..70e49566ac0d9 100644 --- a/tests/ui/did_you_mean/recursion_limit.stderr +++ b/tests/ui/did_you_mean/recursion_limit.stderr @@ -1,15 +1,10 @@ -error[E0275]: overflow evaluating the requirement `K: Send` +error[E0275]: overflow evaluating the requirement `J: Send` --> $DIR/recursion_limit.rs:34:5 | LL | is_send::(); | ^^^^^^^^^^^^ | = help: consider increasing the recursion limit by adding a `#![recursion_limit = "20"]` attribute to your crate (`recursion_limit`) -note: required because it appears within the type `J` - --> $DIR/recursion_limit.rs:24:9 - | -LL | link! { J, K } - | ^ note: required because it appears within the type `I` --> $DIR/recursion_limit.rs:23:9 | diff --git a/tests/ui/error-codes/E0275.stderr b/tests/ui/error-codes/E0275.stderr index cf9a7f69bfbdd..03c37d6f0e1de 100644 --- a/tests/ui/error-codes/E0275.stderr +++ b/tests/ui/error-codes/E0275.stderr @@ -11,7 +11,7 @@ note: required for `Bar Foo for T where Bar: Foo {} | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/error-codes/E0275/E0275.long-type-hash.txt' - = note: 127 redundant requirements hidden + = note: 126 redundant requirements hidden = note: required for `Bar` to implement `Foo` error: aborting due to previous error diff --git a/tests/ui/issues/issue-20413.stderr b/tests/ui/issues/issue-20413.stderr index 202e8463145cc..8891a26784e4b 100644 --- a/tests/ui/issues/issue-20413.stderr +++ b/tests/ui/issues/issue-20413.stderr @@ -20,51 +20,51 @@ note: required for `NoData Foo for T where NoData: Foo { | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' - = note: 127 redundant requirements hidden + = note: 126 redundant requirements hidden = note: required for `NoData` to implement `Foo` -error[E0275]: overflow evaluating the requirement `EvenLessData>>>>>>: Baz` +error[E0275]: overflow evaluating the requirement `AlmostNoData>>>>>>: Bar` --> $DIR/issue-20413.rs:28:42 | LL | impl Bar for T where EvenLessData: Baz { | ^^^ | = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_20413`) -note: required for `AlmostNoData>>>>>>` to implement `Bar` - --> $DIR/issue-20413.rs:28:9 - | -LL | impl Bar for T where EvenLessData: Baz { - | ^^^ ^ --- unsatisfied trait bound introduced here - = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' note: required for `EvenLessData>>>>>>` to implement `Baz` --> $DIR/issue-20413.rs:35:9 | LL | impl Baz for T where AlmostNoData: Bar { | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' - = note: 126 redundant requirements hidden +note: required for `AlmostNoData>>>>>>` to implement `Bar` + --> $DIR/issue-20413.rs:28:9 + | +LL | impl Bar for T where EvenLessData: Baz { + | ^^^ ^ --- unsatisfied trait bound introduced here + = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' + = note: 125 redundant requirements hidden = note: required for `EvenLessData` to implement `Baz` -error[E0275]: overflow evaluating the requirement `AlmostNoData>>>>>>: Bar` +error[E0275]: overflow evaluating the requirement `EvenLessData>>>>>>: Baz` --> $DIR/issue-20413.rs:35:42 | LL | impl Baz for T where AlmostNoData: Bar { | ^^^ | = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_20413`) -note: required for `EvenLessData>>>>>>` to implement `Baz` - --> $DIR/issue-20413.rs:35:9 - | -LL | impl Baz for T where AlmostNoData: Bar { - | ^^^ ^ --- unsatisfied trait bound introduced here - = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' note: required for `AlmostNoData>>>>>>` to implement `Bar` --> $DIR/issue-20413.rs:28:9 | LL | impl Bar for T where EvenLessData: Baz { | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' - = note: 126 redundant requirements hidden +note: required for `EvenLessData>>>>>>` to implement `Baz` + --> $DIR/issue-20413.rs:35:9 + | +LL | impl Baz for T where AlmostNoData: Bar { + | ^^^ ^ --- unsatisfied trait bound introduced here + = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' + = note: 125 redundant requirements hidden = note: required for `AlmostNoData` to implement `Bar` error: aborting due to 4 previous errors diff --git a/tests/ui/traits/cycle-cache-err-60010.stderr b/tests/ui/traits/cycle-cache-err-60010.stderr index eeee997608e6e..2ff16b4af38d4 100644 --- a/tests/ui/traits/cycle-cache-err-60010.stderr +++ b/tests/ui/traits/cycle-cache-err-60010.stderr @@ -1,22 +1,9 @@ -error[E0275]: overflow evaluating the requirement `SalsaStorage: RefUnwindSafe` +error[E0275]: overflow evaluating the requirement `RootDatabase: RefUnwindSafe` --> $DIR/cycle-cache-err-60010.rs:27:13 | LL | _parse: >::Data, | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | - = note: required because it appears within the type `PhantomData` - = note: required because it appears within the type `Unique` - = note: required because it appears within the type `Box` -note: required because it appears within the type `Runtime` - --> $DIR/cycle-cache-err-60010.rs:23:8 - | -LL | struct Runtime { - | ^^^^^^^ -note: required because it appears within the type `RootDatabase` - --> $DIR/cycle-cache-err-60010.rs:20:8 - | -LL | struct RootDatabase { - | ^^^^^^^^^^^^ note: required for `RootDatabase` to implement `SourceDatabase` --> $DIR/cycle-cache-err-60010.rs:44:9 | diff --git a/tests/ui/traits/issue-91949-hangs-on-recursion.rs b/tests/ui/traits/issue-91949-hangs-on-recursion.rs index 6474b2b38e1c0..4eca643a92d4c 100644 --- a/tests/ui/traits/issue-91949-hangs-on-recursion.rs +++ b/tests/ui/traits/issue-91949-hangs-on-recursion.rs @@ -1,6 +1,6 @@ // build-fail // compile-flags: -Zinline-mir=no -// error-pattern: overflow evaluating the requirement `(): Sized` +// error-pattern: overflow evaluating the requirement ` as Iterator>::Item == ()` // error-pattern: function cannot return without recursing // normalize-stderr-test: "long-type-\d+" -> "long-type-hash" diff --git a/tests/ui/traits/issue-91949-hangs-on-recursion.stderr b/tests/ui/traits/issue-91949-hangs-on-recursion.stderr index 1f18c5daf66e3..144990d50f000 100644 --- a/tests/ui/traits/issue-91949-hangs-on-recursion.stderr +++ b/tests/ui/traits/issue-91949-hangs-on-recursion.stderr @@ -12,11 +12,17 @@ LL | recurse(IteratorOfWrapped(elements).map(|t| t.0)) = help: a `loop` may express intention better if this is on purpose = note: `#[warn(unconditional_recursion)]` on by default -error[E0275]: overflow evaluating the requirement `(): Sized` +error[E0275]: overflow evaluating the requirement ` as Iterator>::Item == ()` | = help: consider increasing the recursion limit by adding a `#![recursion_limit = "512"]` attribute to your crate (`issue_91949_hangs_on_recursion`) - = note: required for `std::iter::Empty<()>` to implement `Iterator` - = note: 171 redundant requirements hidden +note: required for `IteratorOfWrapped<(), std::iter::Empty<()>>` to implement `Iterator` + --> $DIR/issue-91949-hangs-on-recursion.rs:16:32 + | +LL | impl> Iterator for IteratorOfWrapped { + | -------- ^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^ + | | + | unsatisfied trait bound introduced here + = note: 256 redundant requirements hidden = note: required for `IteratorOfWrapped<(), Map>, ...>>, ...>>` to implement `Iterator` = note: the full type name has been written to '$TEST_BUILD_DIR/traits/issue-91949-hangs-on-recursion/issue-91949-hangs-on-recursion.long-type-hash.txt' From b8541eb76769798cc34908dc815cc17b6a7a91bc Mon Sep 17 00:00:00 2001 From: lcnr Date: Wed, 15 Mar 2023 14:36:10 +0100 Subject: [PATCH 3/3] use the correct param env --- compiler/rustc_lint/src/for_loops_over_fallibles.rs | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/compiler/rustc_lint/src/for_loops_over_fallibles.rs b/compiler/rustc_lint/src/for_loops_over_fallibles.rs index cb7711034ed63..7b58bf03bbea8 100644 --- a/compiler/rustc_lint/src/for_loops_over_fallibles.rs +++ b/compiler/rustc_lint/src/for_loops_over_fallibles.rs @@ -148,8 +148,7 @@ fn suggest_question_mark<'tcx>( ocx.register_bound( cause, - // FIXME: using the empty param env is wrong, should use the one from `body_id`. - ty::ParamEnv::empty(), + cx.param_env, // Erase any region vids from the type, which may not be resolved infcx.tcx.erase_regions(ty), into_iterator_did,