From 0e16885abd6997897a28627d1ff514c106261a7f Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Tue, 30 Jan 2024 21:48:54 +0000 Subject: [PATCH 1/5] Use deeply_normalize_with_skipped_universes in when processing type outlives --- compiler/rustc_trait_selection/src/regions.rs | 3 ++- .../traits/next-solver/normalize-region-obligations.rs | 9 ++++++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/compiler/rustc_trait_selection/src/regions.rs b/compiler/rustc_trait_selection/src/regions.rs index e8929f114e165..e5a7b27446b4a 100644 --- a/compiler/rustc_trait_selection/src/regions.rs +++ b/compiler/rustc_trait_selection/src/regions.rs @@ -24,12 +24,13 @@ impl<'tcx> InferCtxtRegionExt<'tcx> for InferCtxt<'tcx> { let ty = self.resolve_vars_if_possible(ty); if self.next_trait_solver() { - crate::solve::deeply_normalize( + crate::solve::deeply_normalize_with_skipped_universes( self.at( &ObligationCause::dummy_with_span(origin.span()), outlives_env.param_env, ), ty, + vec![None; ty.outer_exclusive_binder().as_usize()], ) .map_err(|_| ty) } else { diff --git a/tests/ui/traits/next-solver/normalize-region-obligations.rs b/tests/ui/traits/next-solver/normalize-region-obligations.rs index 13c86b630f60e..d189e4893a320 100644 --- a/tests/ui/traits/next-solver/normalize-region-obligations.rs +++ b/tests/ui/traits/next-solver/normalize-region-obligations.rs @@ -1,4 +1,4 @@ -// revisions: normalize_param_env normalize_obligation +// revisions: normalize_param_env normalize_obligation hrtb // check-pass // compile-flags: -Znext-solver @@ -7,16 +7,23 @@ trait Foo { type Gat<'a> where ::Assoc: 'a; #[cfg(normalize_obligation)] type Gat<'a> where Self: 'a; + #[cfg(hrtb)] + type Gat<'b> where for<'a> >::Assoc: 'b; } trait Mirror { type Assoc: ?Sized; } impl Mirror for T { type Assoc = T; } +trait MirrorRegion<'a> { type Assoc: ?Sized; } +impl<'a, T> MirrorRegion<'a> for T { type Assoc = T; } + impl Foo for T { #[cfg(normalize_param_env)] type Gat<'a> = i32 where T: 'a; #[cfg(normalize_obligation)] type Gat<'a> = i32 where ::Assoc: 'a; + #[cfg(hrtb)] + type Gat<'b> = i32 where Self: 'b; } fn main() {} From 7576b77e50f2f8a4f256876dd38563e5e5becdee Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Tue, 30 Jan 2024 21:49:55 +0000 Subject: [PATCH 2/5] Do process_registered_region_obligations in a loop --- .../src/infer/outlives/obligations.rs | 38 +++++++++++-------- 1 file changed, 22 insertions(+), 16 deletions(-) diff --git a/compiler/rustc_infer/src/infer/outlives/obligations.rs b/compiler/rustc_infer/src/infer/outlives/obligations.rs index b10bf98e8b50a..cf68a60e280d1 100644 --- a/compiler/rustc_infer/src/infer/outlives/obligations.rs +++ b/compiler/rustc_infer/src/infer/outlives/obligations.rs @@ -153,22 +153,28 @@ impl<'tcx> InferCtxt<'tcx> { .try_collect() .map_err(|e| (e, SubregionOrigin::AscribeUserTypeProvePredicate(DUMMY_SP)))?; - let my_region_obligations = self.take_registered_region_obligations(); - - for RegionObligation { sup_type, sub_region, origin } in my_region_obligations { - let sup_type = - deeply_normalize_ty(sup_type, origin.clone()).map_err(|e| (e, origin.clone()))?; - debug!(?sup_type, ?sub_region, ?origin); - - let outlives = &mut TypeOutlives::new( - self, - self.tcx, - outlives_env.region_bound_pairs(), - None, - &normalized_caller_bounds, - ); - let category = origin.to_constraint_category(); - outlives.type_must_outlive(origin, sup_type, sub_region, category); + // Must loop since the process of normalizing may itself register region obligations. + loop { + let my_region_obligations = self.take_registered_region_obligations(); + if my_region_obligations.is_empty() { + break; + } + + for RegionObligation { sup_type, sub_region, origin } in my_region_obligations { + let sup_type = deeply_normalize_ty(sup_type, origin.clone()) + .map_err(|e| (e, origin.clone()))?; + debug!(?sup_type, ?sub_region, ?origin); + + let outlives = &mut TypeOutlives::new( + self, + self.tcx, + outlives_env.region_bound_pairs(), + None, + &normalized_caller_bounds, + ); + let category = origin.to_constraint_category(); + outlives.type_must_outlive(origin, sup_type, sub_region, category); + } } Ok(()) From 7d1fda7b40b580e5d8c7de1e3bfef7e35e997cee Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Tue, 30 Jan 2024 21:50:05 +0000 Subject: [PATCH 3/5] Normalize type outlives obligations in NLL --- .../src/type_check/constraint_conversion.rs | 97 +++++++++++++++---- .../src/type_check/free_region_relations.rs | 72 +++++++++----- compiler/rustc_borrowck/src/type_check/mod.rs | 6 +- .../normalize-type-outlives-in-param-env.rs | 18 ++++ .../next-solver/normalize-type-outlives.rs | 13 +++ 5 files changed, 156 insertions(+), 50 deletions(-) create mode 100644 tests/ui/traits/next-solver/normalize-type-outlives-in-param-env.rs create mode 100644 tests/ui/traits/next-solver/normalize-type-outlives.rs diff --git a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs index 52559f9039b65..71035eea5d175 100644 --- a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs +++ b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs @@ -5,10 +5,15 @@ use rustc_infer::infer::outlives::obligations::{TypeOutlives, TypeOutlivesDelega use rustc_infer::infer::region_constraints::{GenericKind, VerifyBound}; use rustc_infer::infer::{self, InferCtxt, SubregionOrigin}; use rustc_middle::mir::{ClosureOutlivesSubject, ClosureRegionRequirements, ConstraintCategory}; +use rustc_middle::traits::ObligationCause; use rustc_middle::ty::GenericArgKind; use rustc_middle::ty::{self, TyCtxt}; use rustc_middle::ty::{TypeFoldable, TypeVisitableExt}; use rustc_span::{Span, DUMMY_SP}; +use rustc_trait_selection::solve::deeply_normalize; +use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt; +use rustc_trait_selection::traits::query::type_op::custom::CustomTypeOp; +use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput}; use crate::{ constraints::OutlivesConstraint, @@ -33,6 +38,7 @@ pub(crate) struct ConstraintConversion<'a, 'tcx> { /// our special inference variable there, we would mess that up. region_bound_pairs: &'a RegionBoundPairs<'tcx>, implicit_region_bound: ty::Region<'tcx>, + param_env: ty::ParamEnv<'tcx>, known_type_outlives_obligations: &'tcx [ty::PolyTypeOutlivesPredicate<'tcx>], locations: Locations, span: Span, @@ -47,6 +53,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { universal_regions: &'a UniversalRegions<'tcx>, region_bound_pairs: &'a RegionBoundPairs<'tcx>, implicit_region_bound: ty::Region<'tcx>, + param_env: ty::ParamEnv<'tcx>, known_type_outlives_obligations: &'tcx [ty::PolyTypeOutlivesPredicate<'tcx>], locations: Locations, span: Span, @@ -59,6 +66,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { universal_regions, region_bound_pairs, implicit_region_bound, + param_env, known_type_outlives_obligations, locations, span, @@ -137,36 +145,83 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { // Extract out various useful fields we'll need below. let ConstraintConversion { tcx, + infcx, + param_env, region_bound_pairs, implicit_region_bound, known_type_outlives_obligations, .. } = *self; - let ty::OutlivesPredicate(k1, r2) = predicate; - match k1.unpack() { - GenericArgKind::Lifetime(r1) => { - let r1_vid = self.to_region_vid(r1); - let r2_vid = self.to_region_vid(r2); - self.add_outlives(r1_vid, r2_vid, constraint_category); - } + let mut outlives_predicates = vec![(predicate, constraint_category)]; + while let Some((ty::OutlivesPredicate(k1, r2), constraint_category)) = + outlives_predicates.pop() + { + match k1.unpack() { + GenericArgKind::Lifetime(r1) => { + let r1_vid = self.to_region_vid(r1); + let r2_vid = self.to_region_vid(r2); + self.add_outlives(r1_vid, r2_vid, constraint_category); + } - GenericArgKind::Type(t1) => { - // we don't actually use this for anything, but - // the `TypeOutlives` code needs an origin. - let origin = infer::RelateParamBound(DUMMY_SP, t1, None); + GenericArgKind::Type(mut t1) => { + // Normalize the type we receive from a `TypeOutlives` obligation + // in the new trait solver. + if infcx.next_trait_solver() { + let result = CustomTypeOp::new( + |ocx| { + match deeply_normalize( + ocx.infcx.at( + &ObligationCause::dummy_with_span(self.span), + param_env, + ), + t1, + ) { + Ok(normalized_ty) => { + t1 = normalized_ty; + } + Err(e) => { + infcx.err_ctxt().report_fulfillment_errors(e); + } + } - TypeOutlives::new( - &mut *self, - tcx, - region_bound_pairs, - Some(implicit_region_bound), - known_type_outlives_obligations, - ) - .type_must_outlive(origin, t1, r2, constraint_category); - } + Ok(()) + }, + "normalize type outlives obligation", + ) + .fully_perform(infcx, self.span); + + match result { + Ok(TypeOpOutput { output: (), constraints, .. }) => { + if let Some(constraints) = constraints { + assert!( + constraints.member_constraints.is_empty(), + "FIXME(-Znext-solver): How do I handle these?" + ); + outlives_predicates + .extend(constraints.outlives.iter().copied()); + } + } + Err(_) => {} + } + } - GenericArgKind::Const(_) => unreachable!(), + // we don't actually use this for anything, but + // the `TypeOutlives` code needs an origin. + let origin = infer::RelateParamBound(DUMMY_SP, t1, None); + + TypeOutlives::new( + &mut *self, + tcx, + region_bound_pairs, + Some(implicit_region_bound), + known_type_outlives_obligations, + ) + .type_must_outlive(origin, t1, r2, constraint_category); + } + + GenericArgKind::Const(_) => unreachable!(), + } } } diff --git a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs index d518f54fd2533..4d53a53ee197b 100644 --- a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs +++ b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs @@ -8,8 +8,11 @@ use rustc_infer::infer::region_constraints::GenericKind; use rustc_infer::infer::InferCtxt; use rustc_middle::mir::ConstraintCategory; use rustc_middle::traits::query::OutlivesBound; +use rustc_middle::traits::ObligationCause; use rustc_middle::ty::{self, RegionVid, Ty, TypeVisitableExt}; -use rustc_span::{ErrorGuaranteed, Span, DUMMY_SP}; +use rustc_span::{ErrorGuaranteed, DUMMY_SP}; +use rustc_trait_selection::solve::deeply_normalize_with_skipped_universes; +use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt; use rustc_trait_selection::traits::query::type_op::{self, TypeOp}; use std::rc::Rc; use type_op::TypeOpOutput; @@ -52,7 +55,6 @@ pub(crate) struct CreateResult<'tcx> { pub(crate) fn create<'tcx>( infcx: &InferCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, - known_type_outlives_obligations: &'tcx [ty::PolyTypeOutlivesPredicate<'tcx>], implicit_region_bound: ty::Region<'tcx>, universal_regions: &Rc>, constraints: &mut MirTypeckRegionConstraints<'tcx>, @@ -60,7 +62,6 @@ pub(crate) fn create<'tcx>( UniversalRegionRelationsBuilder { infcx, param_env, - known_type_outlives_obligations, implicit_region_bound, constraints, universal_regions: universal_regions.clone(), @@ -178,7 +179,6 @@ impl UniversalRegionRelations<'_> { struct UniversalRegionRelationsBuilder<'this, 'tcx> { infcx: &'this InferCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, - known_type_outlives_obligations: &'tcx [ty::PolyTypeOutlivesPredicate<'tcx>], universal_regions: Rc>, implicit_region_bound: ty::Region<'tcx>, constraints: &'this mut MirTypeckRegionConstraints<'tcx>, @@ -222,6 +222,35 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> { self.relate_universal_regions(fr, fr_fn_body); } + // Normalize the assumptions we use to borrowck the program. + let mut constraints = vec![]; + let mut known_type_outlives_obligations = vec![]; + for bound in param_env.caller_bounds() { + let Some(outlives) = bound.as_type_outlives_clause() else { continue }; + let ty::OutlivesPredicate(mut ty, region) = outlives.skip_binder(); + + // In the new solver, normalize the type-outlives obligation assumptions. + if self.infcx.next_trait_solver() { + match deeply_normalize_with_skipped_universes( + self.infcx.at(&ObligationCause::misc(span, defining_ty_def_id), self.param_env), + ty, + vec![None; ty.outer_exclusive_binder().as_usize()], + ) { + Ok(normalized_ty) => { + ty = normalized_ty; + } + Err(e) => { + self.infcx.err_ctxt().report_fulfillment_errors(e); + } + } + } + + known_type_outlives_obligations + .push(outlives.rebind(ty::OutlivesPredicate(ty, region))); + } + let known_type_outlives_obligations = + self.infcx.tcx.arena.alloc_slice(&known_type_outlives_obligations); + let unnormalized_input_output_tys = self .universal_regions .unnormalized_input_tys @@ -239,7 +268,6 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> { // the `relations` is built. let mut normalized_inputs_and_output = Vec::with_capacity(self.universal_regions.unnormalized_input_tys.len() + 1); - let mut constraints = vec![]; for ty in unnormalized_input_output_tys { debug!("build: input_or_output={:?}", ty); // We add implied bounds from both the unnormalized and normalized ty. @@ -304,7 +332,19 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> { } for c in constraints { - self.push_region_constraints(c, span); + constraint_conversion::ConstraintConversion::new( + self.infcx, + &self.universal_regions, + &self.region_bound_pairs, + self.implicit_region_bound, + param_env, + known_type_outlives_obligations, + Locations::All(span), + span, + ConstraintCategory::Internal, + self.constraints, + ) + .convert_all(c); } CreateResult { @@ -313,30 +353,12 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> { outlives: self.outlives.freeze(), inverse_outlives: self.inverse_outlives.freeze(), }), - known_type_outlives_obligations: self.known_type_outlives_obligations, + known_type_outlives_obligations, region_bound_pairs: self.region_bound_pairs, normalized_inputs_and_output, } } - #[instrument(skip(self, data), level = "debug")] - fn push_region_constraints(&mut self, data: &QueryRegionConstraints<'tcx>, span: Span) { - debug!("constraints generated: {:#?}", data); - - constraint_conversion::ConstraintConversion::new( - self.infcx, - &self.universal_regions, - &self.region_bound_pairs, - self.implicit_region_bound, - self.known_type_outlives_obligations, - Locations::All(span), - span, - ConstraintCategory::Internal, - self.constraints, - ) - .convert_all(data); - } - /// Update the type of a single local, which should represent /// either the return type of the MIR or one of its arguments. At /// the same time, compute and add any implied bounds that come diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs index 59c4d9a6c78ca..c65173baea57f 100644 --- a/compiler/rustc_borrowck/src/type_check/mod.rs +++ b/compiler/rustc_borrowck/src/type_check/mod.rs @@ -156,10 +156,6 @@ pub(crate) fn type_check<'mir, 'tcx>( } = free_region_relations::create( infcx, param_env, - // FIXME(-Znext-solver): These are unnormalized. Normalize them. - infcx.tcx.arena.alloc_from_iter( - param_env.caller_bounds().iter().filter_map(|clause| clause.as_type_outlives_clause()), - ), implicit_region_bound, universal_regions, &mut constraints, @@ -1136,6 +1132,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { self.borrowck_context.universal_regions, self.region_bound_pairs, self.implicit_region_bound, + self.param_env, self.known_type_outlives_obligations, locations, locations.span(self.body), @@ -2740,6 +2737,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { self.borrowck_context.universal_regions, self.region_bound_pairs, self.implicit_region_bound, + self.param_env, self.known_type_outlives_obligations, locations, DUMMY_SP, // irrelevant; will be overridden. diff --git a/tests/ui/traits/next-solver/normalize-type-outlives-in-param-env.rs b/tests/ui/traits/next-solver/normalize-type-outlives-in-param-env.rs new file mode 100644 index 0000000000000..7477c56cd5487 --- /dev/null +++ b/tests/ui/traits/next-solver/normalize-type-outlives-in-param-env.rs @@ -0,0 +1,18 @@ +// check-pass +// compile-flags: -Znext-solver + +trait Mirror { + type Assoc; +} + +impl Mirror for T { + type Assoc = T; +} + +fn is_static() {} + +fn test() where ::Assoc: 'static { + is_static::(); +} + +fn main() {} diff --git a/tests/ui/traits/next-solver/normalize-type-outlives.rs b/tests/ui/traits/next-solver/normalize-type-outlives.rs new file mode 100644 index 0000000000000..f50eb6326e239 --- /dev/null +++ b/tests/ui/traits/next-solver/normalize-type-outlives.rs @@ -0,0 +1,13 @@ +// check-pass + +trait Tr<'a> { + type Assoc; +} + +fn outlives<'o, T: 'o>() {} + +fn foo<'a, 'b, T: Tr<'a, Assoc = ()>>() { + outlives::<'b, T::Assoc>(); +} + +fn main() {} From a371059933c11c79f9583ec149d56774e87b940f Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Thu, 1 Feb 2024 18:04:16 +0000 Subject: [PATCH 4/5] Don't hang when there's an infinite loop of outlives obligations --- .../src/type_check/constraint_conversion.rs | 133 ++++++++++-------- .../src/infer/outlives/obligations.rs | 8 +- 2 files changed, 83 insertions(+), 58 deletions(-) diff --git a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs index 71035eea5d175..4c224248945b3 100644 --- a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs +++ b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs @@ -154,74 +154,93 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { } = *self; let mut outlives_predicates = vec![(predicate, constraint_category)]; - while let Some((ty::OutlivesPredicate(k1, r2), constraint_category)) = - outlives_predicates.pop() - { - match k1.unpack() { - GenericArgKind::Lifetime(r1) => { - let r1_vid = self.to_region_vid(r1); - let r2_vid = self.to_region_vid(r2); - self.add_outlives(r1_vid, r2_vid, constraint_category); - } + for iteration in 0.. { + if outlives_predicates.is_empty() { + break; + } - GenericArgKind::Type(mut t1) => { - // Normalize the type we receive from a `TypeOutlives` obligation - // in the new trait solver. - if infcx.next_trait_solver() { - let result = CustomTypeOp::new( - |ocx| { - match deeply_normalize( - ocx.infcx.at( - &ObligationCause::dummy_with_span(self.span), - param_env, - ), - t1, - ) { - Ok(normalized_ty) => { - t1 = normalized_ty; - } - Err(e) => { - infcx.err_ctxt().report_fulfillment_errors(e); + if !self.tcx.recursion_limit().value_within_limit(iteration) { + bug!( + "FIXME(-Znext-solver): Overflowed when processing region obligations: {outlives_predicates:#?}" + ); + } + + let mut next_outlives_predicates = vec![]; + for (ty::OutlivesPredicate(k1, r2), constraint_category) in outlives_predicates { + match k1.unpack() { + GenericArgKind::Lifetime(r1) => { + let r1_vid = self.to_region_vid(r1); + let r2_vid = self.to_region_vid(r2); + self.add_outlives(r1_vid, r2_vid, constraint_category); + } + + GenericArgKind::Type(mut t1) => { + // Normalize the type we receive from a `TypeOutlives` obligation + // in the new trait solver. + if infcx.next_trait_solver() { + let result = CustomTypeOp::new( + |ocx| { + match deeply_normalize( + ocx.infcx.at( + &ObligationCause::dummy_with_span(self.span), + param_env, + ), + t1, + ) { + Ok(normalized_ty) => { + t1 = normalized_ty; + } + Err(e) => { + infcx.err_ctxt().report_fulfillment_errors(e); + } } - } - Ok(()) - }, - "normalize type outlives obligation", - ) - .fully_perform(infcx, self.span); + Ok(()) + }, + "normalize type outlives obligation", + ) + .fully_perform(infcx, self.span); - match result { - Ok(TypeOpOutput { output: (), constraints, .. }) => { - if let Some(constraints) = constraints { - assert!( - constraints.member_constraints.is_empty(), - "FIXME(-Znext-solver): How do I handle these?" - ); - outlives_predicates - .extend(constraints.outlives.iter().copied()); + match result { + Ok(TypeOpOutput { output: (), constraints, .. }) => { + if let Some(constraints) = constraints { + assert!( + constraints.member_constraints.is_empty(), + "no member constraints expected from normalizing: {:#?}", + constraints.member_constraints + ); + next_outlives_predicates + .extend(constraints.outlives.iter().copied()); + } } + Err(_) => {} } - Err(_) => {} } - } - // we don't actually use this for anything, but - // the `TypeOutlives` code needs an origin. - let origin = infer::RelateParamBound(DUMMY_SP, t1, None); + // we don't actually use this for anything, but + // the `TypeOutlives` code needs an origin. + let origin = infer::RelateParamBound(DUMMY_SP, t1, None); - TypeOutlives::new( - &mut *self, - tcx, - region_bound_pairs, - Some(implicit_region_bound), - known_type_outlives_obligations, - ) - .type_must_outlive(origin, t1, r2, constraint_category); - } + TypeOutlives::new( + &mut *self, + tcx, + region_bound_pairs, + Some(implicit_region_bound), + known_type_outlives_obligations, + ) + .type_must_outlive( + origin, + t1, + r2, + constraint_category, + ); + } - GenericArgKind::Const(_) => unreachable!(), + GenericArgKind::Const(_) => unreachable!(), + } } + + outlives_predicates = next_outlives_predicates; } } diff --git a/compiler/rustc_infer/src/infer/outlives/obligations.rs b/compiler/rustc_infer/src/infer/outlives/obligations.rs index cf68a60e280d1..c36d8556d17dd 100644 --- a/compiler/rustc_infer/src/infer/outlives/obligations.rs +++ b/compiler/rustc_infer/src/infer/outlives/obligations.rs @@ -154,12 +154,18 @@ impl<'tcx> InferCtxt<'tcx> { .map_err(|e| (e, SubregionOrigin::AscribeUserTypeProvePredicate(DUMMY_SP)))?; // Must loop since the process of normalizing may itself register region obligations. - loop { + for iteration in 0.. { let my_region_obligations = self.take_registered_region_obligations(); if my_region_obligations.is_empty() { break; } + if !self.tcx.recursion_limit().value_within_limit(iteration) { + bug!( + "FIXME(-Znext-solver): Overflowed when processing region obligations: {my_region_obligations:#?}" + ); + } + for RegionObligation { sup_type, sub_region, origin } in my_region_obligations { let sup_type = deeply_normalize_ty(sup_type, origin.clone()) .map_err(|e| (e, origin.clone()))?; From e951bcff96ac606aad3b7870c7fa64a4a48aa04b Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Fri, 2 Feb 2024 18:31:35 +0000 Subject: [PATCH 5/5] Normalize the whole PolyTypeOutlivesPredicate, more simplifications --- .../src/type_check/constraint_conversion.rs | 84 +++++++++---------- .../src/type_check/free_region_relations.rs | 17 ++-- .../src/infer/error_reporting/mod.rs | 7 +- .../src/infer/lexical_region_resolve/mod.rs | 2 +- .../rustc_infer/src/infer/outlives/mod.rs | 13 +-- .../src/infer/outlives/obligations.rs | 38 +++++---- compiler/rustc_trait_selection/src/regions.rs | 6 +- .../src/traits/auto_trait.rs | 2 +- .../next-solver/specialization-transmute.rs | 2 +- .../specialization-transmute.stderr | 2 +- 10 files changed, 92 insertions(+), 81 deletions(-) diff --git a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs index 4c224248945b3..c97e31701669c 100644 --- a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs +++ b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs @@ -5,13 +5,11 @@ use rustc_infer::infer::outlives::obligations::{TypeOutlives, TypeOutlivesDelega use rustc_infer::infer::region_constraints::{GenericKind, VerifyBound}; use rustc_infer::infer::{self, InferCtxt, SubregionOrigin}; use rustc_middle::mir::{ClosureOutlivesSubject, ClosureRegionRequirements, ConstraintCategory}; +use rustc_middle::traits::query::NoSolution; use rustc_middle::traits::ObligationCause; -use rustc_middle::ty::GenericArgKind; -use rustc_middle::ty::{self, TyCtxt}; -use rustc_middle::ty::{TypeFoldable, TypeVisitableExt}; +use rustc_middle::ty::{self, GenericArgKind, Ty, TyCtxt, TypeFoldable, TypeVisitableExt}; use rustc_span::{Span, DUMMY_SP}; use rustc_trait_selection::solve::deeply_normalize; -use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt; use rustc_trait_selection::traits::query::type_op::custom::CustomTypeOp; use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput}; @@ -146,7 +144,6 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { let ConstraintConversion { tcx, infcx, - param_env, region_bound_pairs, implicit_region_bound, known_type_outlives_obligations, @@ -178,43 +175,10 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { // Normalize the type we receive from a `TypeOutlives` obligation // in the new trait solver. if infcx.next_trait_solver() { - let result = CustomTypeOp::new( - |ocx| { - match deeply_normalize( - ocx.infcx.at( - &ObligationCause::dummy_with_span(self.span), - param_env, - ), - t1, - ) { - Ok(normalized_ty) => { - t1 = normalized_ty; - } - Err(e) => { - infcx.err_ctxt().report_fulfillment_errors(e); - } - } - - Ok(()) - }, - "normalize type outlives obligation", - ) - .fully_perform(infcx, self.span); - - match result { - Ok(TypeOpOutput { output: (), constraints, .. }) => { - if let Some(constraints) = constraints { - assert!( - constraints.member_constraints.is_empty(), - "no member constraints expected from normalizing: {:#?}", - constraints.member_constraints - ); - next_outlives_predicates - .extend(constraints.outlives.iter().copied()); - } - } - Err(_) => {} - } + t1 = self.normalize_and_add_type_outlives_constraints( + t1, + &mut next_outlives_predicates, + ); } // we don't actually use this for anything, but @@ -306,6 +270,42 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { debug!("add_type_test(type_test={:?})", type_test); self.constraints.type_tests.push(type_test); } + + fn normalize_and_add_type_outlives_constraints( + &self, + ty: Ty<'tcx>, + next_outlives_predicates: &mut Vec<( + ty::OutlivesPredicate, ty::Region<'tcx>>, + ConstraintCategory<'tcx>, + )>, + ) -> Ty<'tcx> { + let result = CustomTypeOp::new( + |ocx| { + deeply_normalize( + ocx.infcx.at(&ObligationCause::dummy_with_span(self.span), self.param_env), + ty, + ) + .map_err(|_| NoSolution) + }, + "normalize type outlives obligation", + ) + .fully_perform(self.infcx, self.span); + + match result { + Ok(TypeOpOutput { output: ty, constraints, .. }) => { + if let Some(constraints) = constraints { + assert!( + constraints.member_constraints.is_empty(), + "no member constraints expected from normalizing: {:#?}", + constraints.member_constraints + ); + next_outlives_predicates.extend(constraints.outlives.iter().copied()); + } + ty + } + Err(_) => ty, + } + } } impl<'a, 'b, 'tcx> TypeOutlivesDelegate<'tcx> for &'a mut ConstraintConversion<'b, 'tcx> { diff --git a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs index 4d53a53ee197b..2e0caf4481902 100644 --- a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs +++ b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs @@ -11,7 +11,7 @@ use rustc_middle::traits::query::OutlivesBound; use rustc_middle::traits::ObligationCause; use rustc_middle::ty::{self, RegionVid, Ty, TypeVisitableExt}; use rustc_span::{ErrorGuaranteed, DUMMY_SP}; -use rustc_trait_selection::solve::deeply_normalize_with_skipped_universes; +use rustc_trait_selection::solve::deeply_normalize; use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt; use rustc_trait_selection::traits::query::type_op::{self, TypeOp}; use std::rc::Rc; @@ -226,18 +226,16 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> { let mut constraints = vec![]; let mut known_type_outlives_obligations = vec![]; for bound in param_env.caller_bounds() { - let Some(outlives) = bound.as_type_outlives_clause() else { continue }; - let ty::OutlivesPredicate(mut ty, region) = outlives.skip_binder(); + let Some(mut outlives) = bound.as_type_outlives_clause() else { continue }; // In the new solver, normalize the type-outlives obligation assumptions. if self.infcx.next_trait_solver() { - match deeply_normalize_with_skipped_universes( + match deeply_normalize( self.infcx.at(&ObligationCause::misc(span, defining_ty_def_id), self.param_env), - ty, - vec![None; ty.outer_exclusive_binder().as_usize()], + outlives, ) { - Ok(normalized_ty) => { - ty = normalized_ty; + Ok(normalized_outlives) => { + outlives = normalized_outlives; } Err(e) => { self.infcx.err_ctxt().report_fulfillment_errors(e); @@ -245,8 +243,7 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> { } } - known_type_outlives_obligations - .push(outlives.rebind(ty::OutlivesPredicate(ty, region))); + known_type_outlives_obligations.push(outlives); } let known_type_outlives_obligations = self.infcx.tcx.arena.alloc_slice(&known_type_outlives_obligations); diff --git a/compiler/rustc_infer/src/infer/error_reporting/mod.rs b/compiler/rustc_infer/src/infer/error_reporting/mod.rs index b8344310d5dfd..f74e13db44795 100644 --- a/compiler/rustc_infer/src/infer/error_reporting/mod.rs +++ b/compiler/rustc_infer/src/infer/error_reporting/mod.rs @@ -71,6 +71,7 @@ use rustc_hir::lang_items::LangItem; use rustc_middle::dep_graph::DepContext; use rustc_middle::ty::print::{with_forced_trimmed_paths, PrintError}; use rustc_middle::ty::relate::{self, RelateResult, TypeRelation}; +use rustc_middle::ty::ToPredicate; use rustc_middle::ty::{ self, error::TypeError, IsSuggestable, List, Region, Ty, TyCtxt, TypeFoldable, TypeSuperVisitable, TypeVisitable, TypeVisitableExt, @@ -519,10 +520,12 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { self.report_placeholder_failure(sup_origin, sub_r, sup_r).emit(); } - RegionResolutionError::CannotNormalize(ty, origin) => { + RegionResolutionError::CannotNormalize(clause, origin) => { + let clause: ty::Clause<'tcx> = + clause.map_bound(ty::ClauseKind::TypeOutlives).to_predicate(self.tcx); self.tcx .dcx() - .struct_span_err(origin.span(), format!("cannot normalize `{ty}`")) + .struct_span_err(origin.span(), format!("cannot normalize `{clause}`")) .emit(); } } diff --git a/compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs b/compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs index 4a1169e68e087..6137506d4a994 100644 --- a/compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs +++ b/compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs @@ -99,7 +99,7 @@ pub enum RegionResolutionError<'tcx> { Region<'tcx>, // the placeholder `'b` ), - CannotNormalize(Ty<'tcx>, SubregionOrigin<'tcx>), + CannotNormalize(ty::PolyTypeOutlivesPredicate<'tcx>, SubregionOrigin<'tcx>), } impl<'tcx> RegionResolutionError<'tcx> { diff --git a/compiler/rustc_infer/src/infer/outlives/mod.rs b/compiler/rustc_infer/src/infer/outlives/mod.rs index 926e198b21915..a4f9316b5020f 100644 --- a/compiler/rustc_infer/src/infer/outlives/mod.rs +++ b/compiler/rustc_infer/src/infer/outlives/mod.rs @@ -4,8 +4,8 @@ use super::region_constraints::RegionConstraintData; use super::{InferCtxt, RegionResolutionError, SubregionOrigin}; use crate::infer::free_regions::RegionRelations; use crate::infer::lexical_region_resolve; -use rustc_middle::traits::query::OutlivesBound; -use rustc_middle::ty::{self, Ty}; +use rustc_middle::traits::query::{NoSolution, OutlivesBound}; +use rustc_middle::ty; pub mod components; pub mod env; @@ -49,12 +49,15 @@ impl<'tcx> InferCtxt<'tcx> { pub fn resolve_regions_with_normalize( &self, outlives_env: &OutlivesEnvironment<'tcx>, - deeply_normalize_ty: impl Fn(Ty<'tcx>, SubregionOrigin<'tcx>) -> Result, Ty<'tcx>>, + deeply_normalize_ty: impl Fn( + ty::PolyTypeOutlivesPredicate<'tcx>, + SubregionOrigin<'tcx>, + ) -> Result, NoSolution>, ) -> Vec> { match self.process_registered_region_obligations(outlives_env, deeply_normalize_ty) { Ok(()) => {} - Err((ty, origin)) => { - return vec![RegionResolutionError::CannotNormalize(ty, origin)]; + Err((clause, origin)) => { + return vec![RegionResolutionError::CannotNormalize(clause, origin)]; } }; diff --git a/compiler/rustc_infer/src/infer/outlives/obligations.rs b/compiler/rustc_infer/src/infer/outlives/obligations.rs index c36d8556d17dd..7208f17fb340f 100644 --- a/compiler/rustc_infer/src/infer/outlives/obligations.rs +++ b/compiler/rustc_infer/src/infer/outlives/obligations.rs @@ -68,8 +68,9 @@ use crate::infer::{ use crate::traits::{ObligationCause, ObligationCauseCode}; use rustc_data_structures::undo_log::UndoLogs; use rustc_middle::mir::ConstraintCategory; -use rustc_middle::ty::GenericArgKind; +use rustc_middle::traits::query::NoSolution; use rustc_middle::ty::{self, GenericArgsRef, Region, Ty, TyCtxt, TypeVisitableExt}; +use rustc_middle::ty::{GenericArgKind, PolyTypeOutlivesPredicate}; use rustc_span::DUMMY_SP; use smallvec::smallvec; @@ -125,11 +126,15 @@ impl<'tcx> InferCtxt<'tcx> { /// invoked after all type-inference variables have been bound -- /// right before lexical region resolution. #[instrument(level = "debug", skip(self, outlives_env, deeply_normalize_ty))] - pub fn process_registered_region_obligations( + pub fn process_registered_region_obligations( &self, outlives_env: &OutlivesEnvironment<'tcx>, - mut deeply_normalize_ty: impl FnMut(Ty<'tcx>, SubregionOrigin<'tcx>) -> Result, E>, - ) -> Result<(), (E, SubregionOrigin<'tcx>)> { + mut deeply_normalize_ty: impl FnMut( + PolyTypeOutlivesPredicate<'tcx>, + SubregionOrigin<'tcx>, + ) + -> Result, NoSolution>, + ) -> Result<(), (PolyTypeOutlivesPredicate<'tcx>, SubregionOrigin<'tcx>)> { assert!(!self.in_snapshot(), "cannot process registered region obligations in a snapshot"); let normalized_caller_bounds: Vec<_> = outlives_env @@ -137,21 +142,19 @@ impl<'tcx> InferCtxt<'tcx> { .caller_bounds() .iter() .filter_map(|clause| { - let bound_clause = clause.kind(); - let ty::ClauseKind::TypeOutlives(outlives) = bound_clause.skip_binder() else { - return None; - }; + let outlives = clause.as_type_outlives_clause()?; Some( deeply_normalize_ty( - outlives.0, + outlives, SubregionOrigin::AscribeUserTypeProvePredicate(DUMMY_SP), ) - .map(|ty| bound_clause.rebind(ty::OutlivesPredicate(ty, outlives.1))), + // FIXME(-Znext-solver): How do we accurately report an error span here :( + .map_err(|NoSolution| { + (outlives, SubregionOrigin::AscribeUserTypeProvePredicate(DUMMY_SP)) + }), ) }) - // FIXME(-Znext-solver): How do we accurately report an error here :( - .try_collect() - .map_err(|e| (e, SubregionOrigin::AscribeUserTypeProvePredicate(DUMMY_SP)))?; + .try_collect()?; // Must loop since the process of normalizing may itself register region obligations. for iteration in 0.. { @@ -167,8 +170,13 @@ impl<'tcx> InferCtxt<'tcx> { } for RegionObligation { sup_type, sub_region, origin } in my_region_obligations { - let sup_type = deeply_normalize_ty(sup_type, origin.clone()) - .map_err(|e| (e, origin.clone()))?; + let outlives = ty::Binder::dummy(ty::OutlivesPredicate(sup_type, sub_region)); + let ty::OutlivesPredicate(sup_type, sub_region) = + deeply_normalize_ty(outlives, origin.clone()) + .map_err(|NoSolution| (outlives, origin.clone()))? + .no_bound_vars() + .expect("started with no bound vars, should end with no bound vars"); + debug!(?sup_type, ?sub_region, ?origin); let outlives = &mut TypeOutlives::new( diff --git a/compiler/rustc_trait_selection/src/regions.rs b/compiler/rustc_trait_selection/src/regions.rs index e5a7b27446b4a..756db7cc2063f 100644 --- a/compiler/rustc_trait_selection/src/regions.rs +++ b/compiler/rustc_trait_selection/src/regions.rs @@ -1,5 +1,6 @@ use rustc_infer::infer::outlives::env::OutlivesEnvironment; use rustc_infer::infer::{InferCtxt, RegionResolutionError}; +use rustc_middle::traits::query::NoSolution; use rustc_middle::traits::ObligationCause; pub trait InferCtxtRegionExt<'tcx> { @@ -24,15 +25,14 @@ impl<'tcx> InferCtxtRegionExt<'tcx> for InferCtxt<'tcx> { let ty = self.resolve_vars_if_possible(ty); if self.next_trait_solver() { - crate::solve::deeply_normalize_with_skipped_universes( + crate::solve::deeply_normalize( self.at( &ObligationCause::dummy_with_span(origin.span()), outlives_env.param_env, ), ty, - vec![None; ty.outer_exclusive_binder().as_usize()], ) - .map_err(|_| ty) + .map_err(|_| NoSolution) } else { Ok(ty) } diff --git a/compiler/rustc_trait_selection/src/traits/auto_trait.rs b/compiler/rustc_trait_selection/src/traits/auto_trait.rs index 7933654a91546..81c72fc4b7b03 100644 --- a/compiler/rustc_trait_selection/src/traits/auto_trait.rs +++ b/compiler/rustc_trait_selection/src/traits/auto_trait.rs @@ -179,7 +179,7 @@ impl<'tcx> AutoTraitFinder<'tcx> { } let outlives_env = OutlivesEnvironment::new(full_env); - let _ = infcx.process_registered_region_obligations::(&outlives_env, |ty, _| Ok(ty)); + let _ = infcx.process_registered_region_obligations(&outlives_env, |ty, _| Ok(ty)); let region_data = infcx.inner.borrow_mut().unwrap_region_constraints().region_constraint_data().clone(); diff --git a/tests/ui/traits/next-solver/specialization-transmute.rs b/tests/ui/traits/next-solver/specialization-transmute.rs index e7de564877d09..a0855dd1e1714 100644 --- a/tests/ui/traits/next-solver/specialization-transmute.rs +++ b/tests/ui/traits/next-solver/specialization-transmute.rs @@ -1,5 +1,5 @@ // compile-flags: -Znext-solver -//~^ ERROR cannot normalize `::Id` +//~^ ERROR cannot normalize `::Id: '_` #![feature(specialization)] //~^ WARN the feature `specialization` is incomplete diff --git a/tests/ui/traits/next-solver/specialization-transmute.stderr b/tests/ui/traits/next-solver/specialization-transmute.stderr index a1cf5b761e34f..3100a92e3eb4d 100644 --- a/tests/ui/traits/next-solver/specialization-transmute.stderr +++ b/tests/ui/traits/next-solver/specialization-transmute.stderr @@ -8,7 +8,7 @@ LL | #![feature(specialization)] = help: consider using `min_specialization` instead, which is more stable and complete = note: `#[warn(incomplete_features)]` on by default -error: cannot normalize `::Id` +error: cannot normalize `::Id: '_` error[E0282]: type annotations needed --> $DIR/specialization-transmute.rs:14:23