diff --git a/compiler/rustc_typeck/src/check/writeback.rs b/compiler/rustc_typeck/src/check/writeback.rs index b267909be7bd9..2c0d926dd015e 100644 --- a/compiler/rustc_typeck/src/check/writeback.rs +++ b/compiler/rustc_typeck/src/check/writeback.rs @@ -736,6 +736,26 @@ impl<'cx, 'tcx> Resolver<'cx, 'tcx> { } } +struct EraseEarlyRegions<'tcx> { + tcx: TyCtxt<'tcx>, +} + +impl<'tcx> TypeFolder<'tcx> for EraseEarlyRegions<'tcx> { + fn tcx<'b>(&'b self) -> TyCtxt<'tcx> { + self.tcx + } + fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> { + if ty.has_type_flags(ty::TypeFlags::HAS_POTENTIAL_FREE_REGIONS) { + ty.super_fold_with(self) + } else { + ty + } + } + fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { + if let ty::ReLateBound(..) = r { r } else { self.tcx.lifetimes.re_erased } + } +} + impl<'cx, 'tcx> TypeFolder<'tcx> for Resolver<'cx, 'tcx> { fn tcx<'a>(&'a self) -> TyCtxt<'tcx> { self.tcx @@ -743,7 +763,13 @@ impl<'cx, 'tcx> TypeFolder<'tcx> for Resolver<'cx, 'tcx> { fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> { match self.infcx.fully_resolve(t) { - Ok(t) => self.infcx.tcx.erase_regions(t), + Ok(t) => { + // Do not anonymize late-bound regions + // (e.g. keep `for<'a>` named `for<'a>`). + // This allows NLL to generate error messages that + // refer to the higher-ranked lifetime names written by the user. + EraseEarlyRegions { tcx: self.infcx.tcx }.fold_ty(t) + } Err(_) => { debug!("Resolver::fold_ty: input type `{:?}` not fully resolvable", t); self.report_type_error(t); diff --git a/src/test/ui/hr-subtype/hr-subtype.bound_a_b_ret_a_vs_bound_a_ret_a.nll.stderr b/src/test/ui/hr-subtype/hr-subtype.bound_a_b_ret_a_vs_bound_a_ret_a.nll.stderr index 439a113ef3811..87d826021b703 100644 --- a/src/test/ui/hr-subtype/hr-subtype.bound_a_b_ret_a_vs_bound_a_ret_a.nll.stderr +++ b/src/test/ui/hr-subtype/hr-subtype.bound_a_b_ret_a_vs_bound_a_ret_a.nll.stderr @@ -8,8 +8,8 @@ LL | / check! { bound_a_b_ret_a_vs_bound_a_ret_a: (for<'a,'b> fn(&'a u32, &'b u3 LL | | for<'a> fn(&'a u32, &'a u32) -> &'a u32) } | |_____________________________________________- in this macro invocation | - = note: expected enum `Option fn(&'r u32, &'s u32) -> &'r u32>` - found enum `Option fn(&'r u32, &'r u32) -> &'r u32>` + = note: expected enum `Option fn(&'a u32, &'b u32) -> &'a u32>` + found enum `Option fn(&'a u32, &'a u32) -> &'a u32>` = note: this error originates in the macro `check` (in Nightly builds, run with -Z macro-backtrace for more info) error: aborting due to previous error diff --git a/src/test/ui/hr-subtype/hr-subtype.bound_a_vs_free_x.nll.stderr b/src/test/ui/hr-subtype/hr-subtype.bound_a_vs_free_x.nll.stderr index 61b3f0ca2847c..bd97f6f090646 100644 --- a/src/test/ui/hr-subtype/hr-subtype.bound_a_vs_free_x.nll.stderr +++ b/src/test/ui/hr-subtype/hr-subtype.bound_a_vs_free_x.nll.stderr @@ -8,7 +8,7 @@ LL | / check! { bound_a_vs_free_x: (for<'a> fn(&'a u32), LL | | fn(&'x u32)) } | |______________- in this macro invocation | - = note: expected enum `Option fn(&'r u32)>` + = note: expected enum `Option fn(&'a u32)>` found enum `Option` = note: this error originates in the macro `check` (in Nightly builds, run with -Z macro-backtrace for more info) diff --git a/src/test/ui/hr-subtype/hr-subtype.bound_inv_a_b_vs_bound_inv_a.nll.stderr b/src/test/ui/hr-subtype/hr-subtype.bound_inv_a_b_vs_bound_inv_a.nll.stderr index 75e2ba58f33fb..874909bf486c8 100644 --- a/src/test/ui/hr-subtype/hr-subtype.bound_inv_a_b_vs_bound_inv_a.nll.stderr +++ b/src/test/ui/hr-subtype/hr-subtype.bound_inv_a_b_vs_bound_inv_a.nll.stderr @@ -8,8 +8,8 @@ LL | / check! { bound_inv_a_b_vs_bound_inv_a: (for<'a,'b> fn(Inv<'a>, Inv<'b>), LL | | for<'a> fn(Inv<'a>, Inv<'a>)) } | |__________________________________- in this macro invocation | - = note: expected enum `Option fn(Inv<'r>, Inv<'s>)>` - found enum `Option fn(Inv<'r>, Inv<'r>)>` + = note: expected enum `Option fn(Inv<'a>, Inv<'b>)>` + found enum `Option fn(Inv<'a>, Inv<'a>)>` = note: this error originates in the macro `check` (in Nightly builds, run with -Z macro-backtrace for more info) error[E0308]: mismatched types @@ -22,8 +22,8 @@ LL | / check! { bound_inv_a_b_vs_bound_inv_a: (for<'a,'b> fn(Inv<'a>, Inv<'b>), LL | | for<'a> fn(Inv<'a>, Inv<'a>)) } | |__________________________________- in this macro invocation | - = note: expected enum `Option fn(Inv<'r>, Inv<'s>)>` - found enum `Option fn(Inv<'r>, Inv<'r>)>` + = note: expected enum `Option fn(Inv<'a>, Inv<'b>)>` + found enum `Option fn(Inv<'a>, Inv<'a>)>` = note: this error originates in the macro `check` (in Nightly builds, run with -Z macro-backtrace for more info) error: aborting due to 2 previous errors diff --git a/src/test/ui/lub-glb/old-lub-glb-hr-noteq1.nll.stderr b/src/test/ui/lub-glb/old-lub-glb-hr-noteq1.nll.stderr index 3fdc2da9f1e2e..5ac392914e57b 100644 --- a/src/test/ui/lub-glb/old-lub-glb-hr-noteq1.nll.stderr +++ b/src/test/ui/lub-glb/old-lub-glb-hr-noteq1.nll.stderr @@ -4,8 +4,8 @@ error[E0308]: mismatched types LL | _ => y, | ^ one type is more general than the other | - = note: expected fn pointer `for<'r, 's> fn(&'r u8, &'s u8) -> &'r u8` - found fn pointer `for<'r> fn(&'r u8, &'r u8) -> &'r u8` + = note: expected fn pointer `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8` + found fn pointer `for<'a> fn(&'a u8, &'a u8) -> &'a u8` error: aborting due to previous error diff --git a/src/test/ui/lub-glb/old-lub-glb-object.nll.stderr b/src/test/ui/lub-glb/old-lub-glb-object.nll.stderr index ad14d6b7521bc..355f0754ab1b8 100644 --- a/src/test/ui/lub-glb/old-lub-glb-object.nll.stderr +++ b/src/test/ui/lub-glb/old-lub-glb-object.nll.stderr @@ -4,8 +4,8 @@ error[E0308]: mismatched types LL | _ => y, | ^ one type is more general than the other | - = note: expected trait object `dyn for<'r, 's> Foo<&'r u8, &'s u8>` - found trait object `dyn for<'r> Foo<&'r u8, &'r u8>` + = note: expected trait object `dyn for<'a, 'b> Foo<&'a u8, &'b u8>` + found trait object `dyn for<'a> Foo<&'a u8, &'a u8>` error[E0308]: mismatched types --> $DIR/old-lub-glb-object.rs:10:14 @@ -13,8 +13,8 @@ error[E0308]: mismatched types LL | _ => y, | ^ one type is more general than the other | - = note: expected trait object `dyn for<'r, 's> Foo<&'r u8, &'s u8>` - found trait object `dyn for<'r> Foo<&'r u8, &'r u8>` + = note: expected trait object `dyn for<'a, 'b> Foo<&'a u8, &'b u8>` + found trait object `dyn for<'a> Foo<&'a u8, &'a u8>` error: aborting due to 2 previous errors diff --git a/src/test/ui/nll/relate_tys/fn-subtype.stderr b/src/test/ui/nll/relate_tys/fn-subtype.stderr index 94def69008677..6256c4a01d386 100644 --- a/src/test/ui/nll/relate_tys/fn-subtype.stderr +++ b/src/test/ui/nll/relate_tys/fn-subtype.stderr @@ -4,7 +4,7 @@ error[E0308]: mismatched types LL | let y: for<'a> fn(&'a ()) = x; | ^ one type is more general than the other | - = note: expected fn pointer `for<'r> fn(&'r ())` + = note: expected fn pointer `for<'a> fn(&'a ())` found fn pointer `fn(&())` error: aborting due to previous error diff --git a/src/test/ui/nll/relate_tys/hr-fn-aaa-as-aba.stderr b/src/test/ui/nll/relate_tys/hr-fn-aaa-as-aba.stderr index 8c1eaeb6aa7b9..b839015f97f61 100644 --- a/src/test/ui/nll/relate_tys/hr-fn-aaa-as-aba.stderr +++ b/src/test/ui/nll/relate_tys/hr-fn-aaa-as-aba.stderr @@ -4,7 +4,7 @@ error[E0308]: mismatched types LL | let a: for<'a, 'b> fn(&'a u32, &'b u32) -> &'a u32 = make_it(); | ^^^^^^^^^ one type is more general than the other | - = note: expected fn pointer `for<'r, 's> fn(&'r u32, &'s u32) -> &'r u32` + = note: expected fn pointer `for<'a, 'b> fn(&'a u32, &'b u32) -> &'a u32` found fn pointer `for<'a> fn(&'a u32, &'a u32) -> &'a u32` error[E0308]: mismatched types @@ -14,7 +14,7 @@ LL | let _: for<'a, 'b> fn(&'a u32, &'b u32) -> &'a u32 = make_it(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other | = note: expected fn pointer `for<'a, 'b> fn(&'a u32, &'b u32) -> &'a u32` - found fn pointer `for<'r> fn(&'r u32, &'r u32) -> &'r u32` + found fn pointer `for<'a> fn(&'a u32, &'a u32) -> &'a u32` error: aborting due to 2 previous errors diff --git a/src/test/ui/nll/relate_tys/trait-hrtb.stderr b/src/test/ui/nll/relate_tys/trait-hrtb.stderr index 60a7f20444680..6d144a4be6ed3 100644 --- a/src/test/ui/nll/relate_tys/trait-hrtb.stderr +++ b/src/test/ui/nll/relate_tys/trait-hrtb.stderr @@ -4,7 +4,7 @@ error[E0308]: mismatched types LL | let y: Box Foo<'a>> = x; | ^ one type is more general than the other | - = note: expected trait object `dyn for<'r> Foo<'r>` + = note: expected trait object `dyn for<'a> Foo<'a>` found trait object `dyn Foo<'_>` error: aborting due to previous error diff --git a/src/test/ui/rfc1623.nll.stderr b/src/test/ui/rfc1623.nll.stderr index cc247bbcb1199..7f15c1c1f5770 100644 --- a/src/test/ui/rfc1623.nll.stderr +++ b/src/test/ui/rfc1623.nll.stderr @@ -31,7 +31,7 @@ LL | | LL | | }; | |_^ one type is more general than the other | - = note: expected type `for<'r, 's> Fn<(&'r Foo<'s>,)>` + = note: expected type `for<'a, 'b> Fn<(&'a Foo<'b>,)>` found type `Fn<(&Foo<'_>,)>` error[E0308]: mismatched types @@ -46,7 +46,7 @@ LL | | LL | | }; | |_^ one type is more general than the other | - = note: expected type `for<'r, 's> Fn<(&'r Foo<'s>,)>` + = note: expected type `for<'a, 'b> Fn<(&'a Foo<'b>,)>` found type `Fn<(&Foo<'_>,)>` error: implementation of `FnOnce` is not general enough @@ -61,7 +61,7 @@ LL | | LL | | }; | |_^ implementation of `FnOnce` is not general enough | - = note: `fn(&'2 Foo<'_>) -> &'2 Foo<'_> {id::<&'2 Foo<'_>>}` must implement `FnOnce<(&'1 Foo<'_>,)>`, for any lifetime `'1`... + = note: `fn(&'2 Foo<'_>) -> &'2 Foo<'_> {id::<&'2 Foo<'_>>}` must implement `FnOnce<(&'1 Foo<'b>,)>`, for any lifetime `'1`... = note: ...but it actually implements `FnOnce<(&'2 Foo<'_>,)>`, for some specific lifetime `'2` error: implementation of `FnOnce` is not general enough @@ -76,7 +76,7 @@ LL | | LL | | }; | |_^ implementation of `FnOnce` is not general enough | - = note: `fn(&Foo<'2>) -> &Foo<'2> {id::<&Foo<'2>>}` must implement `FnOnce<(&Foo<'1>,)>`, for any lifetime `'1`... + = note: `fn(&Foo<'2>) -> &Foo<'2> {id::<&Foo<'2>>}` must implement `FnOnce<(&'a Foo<'1>,)>`, for any lifetime `'1`... = note: ...but it actually implements `FnOnce<(&Foo<'2>,)>`, for some specific lifetime `'2` error: aborting due to 5 previous errors