@@ -40,7 +40,6 @@ use rustc_span::{sym, BytePos, Span, DUMMY_SP};
40
40
use rustc_target:: spec:: abi;
41
41
use rustc_trait_selection:: traits:: wf:: object_region_bounds;
42
42
use rustc_trait_selection:: traits:: { self , NormalizeExt , ObligationCtxt } ;
43
- use rustc_type_ir:: fold:: { TypeFoldable , TypeFolder , TypeSuperFoldable } ;
44
43
45
44
use std:: fmt:: Display ;
46
45
use std:: slice;
@@ -1609,130 +1608,105 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
1609
1608
let cause = ObligationCause :: misc ( span, block. owner . def_id ) ;
1610
1609
1611
1610
let mut fulfillment_errors = Vec :: new ( ) ;
1612
- let mut applicable_candidates: Vec < _ > = infcx. probe ( |_| {
1613
- // Regions are not considered during selection.
1614
- let self_ty = self_ty
1615
- . fold_with ( & mut BoundVarEraser { tcx, universe : infcx. create_next_universe ( ) } ) ;
1616
-
1617
- struct BoundVarEraser < ' tcx > {
1618
- tcx : TyCtxt < ' tcx > ,
1619
- universe : ty:: UniverseIndex ,
1620
- }
1621
-
1622
- // FIXME(non_lifetime_binders): Don't assign the same universe to each placeholder.
1623
- impl < ' tcx > TypeFolder < TyCtxt < ' tcx > > for BoundVarEraser < ' tcx > {
1624
- fn interner ( & self ) -> TyCtxt < ' tcx > {
1625
- self . tcx
1626
- }
1627
-
1628
- fn fold_region ( & mut self , r : ty:: Region < ' tcx > ) -> ty:: Region < ' tcx > {
1629
- // FIXME(@lcnr): This is broken, erasing bound regions
1630
- // impacts selection as it results in different types.
1631
- if r. is_bound ( ) { self . tcx . lifetimes . re_erased } else { r }
1632
- }
1633
-
1634
- fn fold_ty ( & mut self , ty : Ty < ' tcx > ) -> Ty < ' tcx > {
1635
- match * ty. kind ( ) {
1636
- ty:: Bound ( _, bv) => Ty :: new_placeholder (
1637
- self . tcx ,
1638
- ty:: PlaceholderType { universe : self . universe , bound : bv } ,
1639
- ) ,
1640
- _ => ty. super_fold_with ( self ) ,
1641
- }
1642
- }
1643
-
1644
- fn fold_const (
1645
- & mut self ,
1646
- ct : ty:: Const < ' tcx > ,
1647
- ) -> <TyCtxt < ' tcx > as rustc_type_ir:: Interner >:: Const {
1648
- assert ! ( !ct. ty( ) . has_escaping_bound_vars( ) ) ;
1649
-
1650
- match ct. kind ( ) {
1651
- ty:: ConstKind :: Bound ( _, bv) => ty:: Const :: new_placeholder (
1652
- self . tcx ,
1653
- ty:: PlaceholderConst { universe : self . universe , bound : bv } ,
1654
- ct. ty ( ) ,
1655
- ) ,
1656
- _ => ct. super_fold_with ( self ) ,
1657
- }
1658
- }
1659
- }
1611
+ let mut universes = if self_ty. has_escaping_bound_vars ( ) {
1612
+ vec ! [ None ; self_ty. outer_exclusive_binder( ) . as_usize( ) ]
1613
+ } else {
1614
+ vec ! [ ]
1615
+ } ;
1660
1616
1661
- let InferOk { value : self_ty, obligations } =
1662
- infcx. at ( & cause, param_env) . normalize ( self_ty) ;
1617
+ crate :: traits:: project:: with_replaced_escaping_bound_vars (
1618
+ infcx,
1619
+ & mut universes,
1620
+ self_ty,
1621
+ |self_ty| {
1622
+ let InferOk { value : self_ty, obligations } =
1623
+ infcx. at ( & cause, param_env) . normalize ( self_ty) ;
1663
1624
1664
- candidates
1665
- . iter ( )
1666
- . copied ( )
1667
- . filter ( |& ( impl_, _) | {
1668
- infcx. probe ( |_| {
1669
- let ocx = ObligationCtxt :: new ( infcx) ;
1670
- ocx. register_obligations ( obligations. clone ( ) ) ;
1671
-
1672
- let impl_args = infcx. fresh_args_for_item ( span, impl_) ;
1673
- let impl_ty = tcx. type_of ( impl_) . instantiate ( tcx, impl_args) ;
1674
- let impl_ty = ocx. normalize ( & cause, param_env, impl_ty) ;
1675
-
1676
- // Check that the self types can be related.
1677
- if ocx. eq ( & ObligationCause :: dummy ( ) , param_env, impl_ty, self_ty) . is_err ( ) {
1678
- return false ;
1679
- }
1625
+ let mut applicable_candidates: Vec < _ > = candidates
1626
+ . iter ( )
1627
+ . copied ( )
1628
+ . filter ( |& ( impl_, _) | {
1629
+ infcx. probe ( |_| {
1630
+ let ocx = ObligationCtxt :: new ( infcx) ;
1631
+ ocx. register_obligations ( obligations. clone ( ) ) ;
1632
+
1633
+ let impl_args = infcx. fresh_args_for_item ( span, impl_) ;
1634
+ let impl_ty = tcx. type_of ( impl_) . instantiate ( tcx, impl_args) ;
1635
+ let impl_ty = ocx. normalize ( & cause, param_env, impl_ty) ;
1636
+
1637
+ // Check that the self types can be related.
1638
+ if ocx
1639
+ . eq ( & ObligationCause :: dummy ( ) , param_env, impl_ty, self_ty)
1640
+ . is_err ( )
1641
+ {
1642
+ return false ;
1643
+ }
1680
1644
1681
- // Check whether the impl imposes obligations we have to worry about.
1682
- let impl_bounds = tcx. predicates_of ( impl_) . instantiate ( tcx, impl_args) ;
1683
- let impl_bounds = ocx. normalize ( & cause, param_env, impl_bounds) ;
1684
- let impl_obligations = traits:: predicates_for_generics (
1685
- |_, _| cause. clone ( ) ,
1686
- param_env,
1687
- impl_bounds,
1688
- ) ;
1689
- ocx. register_obligations ( impl_obligations) ;
1645
+ // Check whether the impl imposes obligations we have to worry about.
1646
+ let impl_bounds = tcx. predicates_of ( impl_) . instantiate ( tcx, impl_args) ;
1647
+ let impl_bounds = ocx. normalize ( & cause, param_env, impl_bounds) ;
1648
+ let impl_obligations = traits:: predicates_for_generics (
1649
+ |_, _| cause. clone ( ) ,
1650
+ param_env,
1651
+ impl_bounds,
1652
+ ) ;
1653
+ ocx. register_obligations ( impl_obligations) ;
1690
1654
1691
- let mut errors = ocx. select_where_possible ( ) ;
1692
- if !errors. is_empty ( ) {
1693
- fulfillment_errors. append ( & mut errors) ;
1694
- return false ;
1695
- }
1655
+ let mut errors = ocx. select_where_possible ( ) ;
1656
+ if !errors. is_empty ( ) {
1657
+ fulfillment_errors. append ( & mut errors) ;
1658
+ return false ;
1659
+ }
1696
1660
1697
- true
1661
+ true
1662
+ } )
1698
1663
} )
1699
- } )
1700
- . collect ( )
1701
- } ) ;
1664
+ . collect ( ) ;
1702
1665
1703
- if applicable_candidates. len ( ) > 1 {
1704
- return Err ( self . complain_about_ambiguous_inherent_assoc_type (
1705
- name,
1706
- applicable_candidates. into_iter ( ) . map ( |( _, ( candidate, _) ) | candidate) . collect ( ) ,
1707
- span,
1708
- ) ) ;
1709
- }
1666
+ if applicable_candidates. len ( ) > 1 {
1667
+ return Err ( self . complain_about_ambiguous_inherent_assoc_type (
1668
+ name,
1669
+ applicable_candidates
1670
+ . into_iter ( )
1671
+ . map ( |( _, ( candidate, _) ) | candidate)
1672
+ . collect ( ) ,
1673
+ span,
1674
+ ) ) ;
1675
+ }
1710
1676
1711
- if let Some ( ( impl_, ( assoc_item, def_scope) ) ) = applicable_candidates. pop ( ) {
1712
- self . check_assoc_ty ( assoc_item, name, def_scope, block, span) ;
1713
-
1714
- // FIXME(fmease): Currently creating throwaway `parent_args` to please
1715
- // `create_args_for_associated_item`. Modify the latter instead (or sth. similar) to
1716
- // not require the parent args logic.
1717
- let parent_args = ty:: GenericArgs :: identity_for_item ( tcx, impl_) ;
1718
- let args = self . create_args_for_associated_item ( span, assoc_item, segment, parent_args) ;
1719
- let args = tcx. mk_args_from_iter (
1720
- std:: iter:: once ( ty:: GenericArg :: from ( self_ty) )
1721
- . chain ( args. into_iter ( ) . skip ( parent_args. len ( ) ) ) ,
1722
- ) ;
1677
+ if let Some ( ( impl_, ( assoc_item, def_scope) ) ) = applicable_candidates. pop ( ) {
1678
+ self . check_assoc_ty ( assoc_item, name, def_scope, block, span) ;
1723
1679
1724
- let ty = Ty :: new_alias ( tcx, ty:: Inherent , ty:: AliasTy :: new ( tcx, assoc_item, args) ) ;
1680
+ // FIXME(fmease): Currently creating throwaway `parent_args` to please
1681
+ // `create_args_for_associated_item`. Modify the latter instead (or sth. similar) to
1682
+ // not require the parent args logic.
1683
+ let parent_args = ty:: GenericArgs :: identity_for_item ( tcx, impl_) ;
1684
+ let args = self . create_args_for_associated_item (
1685
+ span,
1686
+ assoc_item,
1687
+ segment,
1688
+ parent_args,
1689
+ ) ;
1690
+ let args = tcx. mk_args_from_iter (
1691
+ std:: iter:: once ( ty:: GenericArg :: from ( self_ty) )
1692
+ . chain ( args. into_iter ( ) . skip ( parent_args. len ( ) ) ) ,
1693
+ ) ;
1725
1694
1726
- return Ok ( Some ( ( ty , assoc_item ) ) ) ;
1727
- }
1695
+ let ty =
1696
+ Ty :: new_alias ( tcx , ty :: Inherent , ty :: AliasTy :: new ( tcx , assoc_item , args ) ) ;
1728
1697
1729
- Err ( self . complain_about_inherent_assoc_type_not_found (
1730
- name,
1731
- self_ty,
1732
- candidates,
1733
- fulfillment_errors,
1734
- span,
1735
- ) )
1698
+ return Ok ( Some ( ( ty, assoc_item) ) ) ;
1699
+ }
1700
+
1701
+ Err ( self . complain_about_inherent_assoc_type_not_found (
1702
+ name,
1703
+ self_ty,
1704
+ candidates,
1705
+ fulfillment_errors,
1706
+ span,
1707
+ ) )
1708
+ } ,
1709
+ )
1736
1710
}
1737
1711
1738
1712
fn lookup_assoc_ty (
0 commit comments