Rollup of 11 pull requests

Cargo.lock

@@ -5389,7 +5389,7 @@ dependencies = [
  "chrono",
  "lazy_static",
  "matchers",
- "parking_lot 0.11.0",
+ "parking_lot 0.9.0",
  "regex",
  "serde",
  "serde_json",

compiler/rustc_ast_lowering/src/lib.rs

@@ -507,7 +507,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         let count = generics
                             .params
                             .iter()
-                            .filter(|param| matches!(param.kind, ast::GenericParamKind::Lifetime { .. }))
+                            .filter(|param| {
+                                matches!(param.kind, ast::GenericParamKind::Lifetime { .. })
+                            })
                             .count();
                         self.lctx.type_def_lifetime_params.insert(def_id.to_def_id(), count);
                     }

compiler/rustc_builtin_macros/src/deriving/generic/mod.rs

@@ -598,7 +598,7 @@ impl<'a> TraitDef<'a> {
 
             let mut ty_params = params
                 .iter()
-                .filter(|param| matches!(param.kind,  ast::GenericParamKind::Type{..}))
+                .filter(|param| matches!(param.kind, ast::GenericParamKind::Type { .. }))
                 .peekable();
 
             if ty_params.peek().is_some() {

compiler/rustc_errors/src/diagnostic_builder.rs

@@ -36,7 +36,7 @@ macro_rules! forward_inner_docs {
     ($e:expr => $i:item) => {
         #[doc = $e]
         $i
-    }
+    };
 }
 
 /// In general, the `DiagnosticBuilder` uses deref to allow access to

compiler/rustc_errors/src/snippet.rs

@@ -122,11 +122,13 @@ impl Annotation {
     }
 
     pub fn is_multiline(&self) -> bool {
-        matches!(self.annotation_type,
+        matches!(
+            self.annotation_type,
             AnnotationType::Multiline(_)
-            | AnnotationType::MultilineStart(_)
-            | AnnotationType::MultilineLine(_)
-            | AnnotationType::MultilineEnd(_))
+                | AnnotationType::MultilineStart(_)
+                | AnnotationType::MultilineLine(_)
+                | AnnotationType::MultilineEnd(_)
+        )
     }
 
     pub fn len(&self) -> usize {
@@ -158,7 +160,10 @@ impl Annotation {
 
     pub fn takes_space(&self) -> bool {
         // Multiline annotations always have to keep vertical space.
-        matches!(self.annotation_type, AnnotationType::MultilineStart(_) | AnnotationType::MultilineEnd(_))
+        matches!(
+            self.annotation_type,
+            AnnotationType::MultilineStart(_) | AnnotationType::MultilineEnd(_)
+        )
     }
 }
 

compiler/rustc_hir/src/hir.rs

@@ -1543,10 +1543,10 @@ pub fn is_range_literal(expr: &Expr<'_>) -> bool {
             **qpath,
             QPath::LangItem(
                 LangItem::Range
-                | LangItem::RangeTo
-                | LangItem::RangeFrom
-                | LangItem::RangeFull
-                | LangItem::RangeToInclusive,
+                    | LangItem::RangeTo
+                    | LangItem::RangeFrom
+                    | LangItem::RangeFull
+                    | LangItem::RangeToInclusive,
                 _,
             )
         ),

compiler/rustc_infer/src/infer/combine.rs

@@ -542,10 +542,6 @@ impl TypeRelation<'tcx> for Generalizer<'_, 'tcx> {
         true
     }
 
-    fn visit_ct_substs(&self) -> bool {
-        true
-    }
-
     fn binders<T>(
         &mut self,
         a: ty::Binder<T>,
@@ -736,6 +732,16 @@ impl TypeRelation<'tcx> for Generalizer<'_, 'tcx> {
                     }
                 }
             }
+            ty::ConstKind::Unevaluated(def, substs, promoted)
+                if self.tcx().lazy_normalization() =>
+            {
+                assert_eq!(promoted, None);
+                let substs = self.relate_with_variance(ty::Variance::Invariant, substs, substs)?;
+                Ok(self.tcx().mk_const(ty::Const {
+                    ty: c.ty,
+                    val: ty::ConstKind::Unevaluated(def, substs, promoted),
+                }))
+            }
             _ => relate::super_relate_consts(self, c, c),
         }
     }
@@ -821,10 +827,6 @@ impl TypeRelation<'tcx> for ConstInferUnifier<'_, 'tcx> {
         true
     }
 
-    fn visit_ct_substs(&self) -> bool {
-        true
-    }
-
     fn relate_with_variance<T: Relate<'tcx>>(
         &mut self,
         _variance: ty::Variance,
@@ -958,6 +960,16 @@ impl TypeRelation<'tcx> for ConstInferUnifier<'_, 'tcx> {
                     }
                 }
             }
+            ty::ConstKind::Unevaluated(def, substs, promoted)
+                if self.tcx().lazy_normalization() =>
+            {
+                assert_eq!(promoted, None);
+                let substs = self.relate_with_variance(ty::Variance::Invariant, substs, substs)?;
+                Ok(self.tcx().mk_const(ty::Const {
+                    ty: c.ty,
+                    val: ty::ConstKind::Unevaluated(def, substs, promoted),
+                }))
+            }
             _ => relate::super_relate_consts(self, c, c),
         }
     }

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/trait_impl_difference.rs

@@ -132,7 +132,12 @@ impl Visitor<'tcx> for TypeParamSpanVisitor<'tcx> {
                 [segment]
                     if segment
                         .res
-                        .map(|res| matches!(res, Res::SelfTy(_, _) | Res::Def(hir::def::DefKind::TyParam, _)))
+                        .map(|res| {
+                            matches!(
+                                res,
+                                Res::SelfTy(_, _) | Res::Def(hir::def::DefKind::TyParam, _)
+                            )
+                        })
                         .unwrap_or(false) =>
                 {
                     self.types.push(path.span);

compiler/rustc_lint_defs/src/builtin.rs

@@ -2968,6 +2968,7 @@ declare_lint_pass! {
         UNSUPPORTED_NAKED_FUNCTIONS,
         MISSING_ABI,
         SEMICOLON_IN_EXPRESSIONS_FROM_MACROS,
+        DISJOINT_CAPTURE_DROP_REORDER,
     ]
 }
 
@@ -2994,6 +2995,51 @@ declare_lint! {
     "detects doc comments that aren't used by rustdoc"
 }
 
+declare_lint! {
+    /// The `disjoint_capture_drop_reorder` lint detects variables that aren't completely
+    /// captured when the feature `capture_disjoint_fields` is enabled and it affects the Drop
+    /// order of at least one path starting at this variable.
+    ///
+    /// ### Example
+    ///
+    /// ```rust,compile_fail
+    /// # #![deny(disjoint_capture_drop_reorder)]
+    /// # #![allow(unused)]
+    /// struct FancyInteger(i32);
+    ///
+    /// impl Drop for FancyInteger {
+    ///     fn drop(&mut self) {
+    ///         println!("Just dropped {}", self.0);
+    ///     }
+    /// }
+    ///
+    /// struct Point { x: FancyInteger, y: FancyInteger }
+    ///
+    /// fn main() {
+    ///   let p = Point { x: FancyInteger(10), y: FancyInteger(20) };
+    ///
+    ///   let c = || {
+    ///      let x = p.x;
+    ///   };
+    ///
+    ///   c();
+    ///
+    ///   // ... More code ...
+    /// }
+    /// ```
+    ///
+    /// {{produces}}
+    ///
+    /// ### Explanation
+    ///
+    /// In the above example `p.y` will be dropped at the end of `f` instead of with `c` if
+    /// the feature `capture_disjoint_fields` is enabled.
+    pub DISJOINT_CAPTURE_DROP_REORDER,
+    Allow,
+    "Drop reorder because of `capture_disjoint_fields`"
+
+}
+
 declare_lint_pass!(UnusedDocComment => [UNUSED_DOC_COMMENTS]);
 
 declare_lint! {

compiler/rustc_middle/src/hir/map/mod.rs

@@ -559,9 +559,9 @@ impl<'hir> Map<'hir> {
             self.find(self.get_parent_node(id)),
             Some(
                 Node::Item(_)
-                | Node::TraitItem(_)
-                | Node::ImplItem(_)
-                | Node::Expr(Expr { kind: ExprKind::Closure(..), .. }),
+                    | Node::TraitItem(_)
+                    | Node::ImplItem(_)
+                    | Node::Expr(Expr { kind: ExprKind::Closure(..), .. }),
             )
         )
     }

compiler/rustc_middle/src/mir/mod.rs

@@ -962,8 +962,7 @@ impl<'tcx> LocalDecl<'tcx> {
                     opt_ty_info: _,
                     opt_match_place: _,
                     pat_span: _,
-                })
-                | BindingForm::ImplicitSelf(ImplicitSelfKind::Imm),
+                }) | BindingForm::ImplicitSelf(ImplicitSelfKind::Imm),
             )))
         )
     }
@@ -980,8 +979,7 @@ impl<'tcx> LocalDecl<'tcx> {
                     opt_ty_info: _,
                     opt_match_place: _,
                     pat_span: _,
-                })
-                | BindingForm::ImplicitSelf(_),
+                }) | BindingForm::ImplicitSelf(_),
             )))
         )
     }

compiler/rustc_middle/src/ty/diagnostics.rs

@@ -12,13 +12,17 @@ impl<'tcx> TyS<'tcx> {
     pub fn is_primitive_ty(&self) -> bool {
         matches!(
             self.kind(),
-            Bool | Char | Str | Int(_) | Uint(_) | Float(_)
-            | Infer(
-                InferTy::IntVar(_)
-                | InferTy::FloatVar(_)
-                | InferTy::FreshIntTy(_)
-                | InferTy::FreshFloatTy(_)
-            )
+            Bool | Char
+                | Str
+                | Int(_)
+                | Uint(_)
+                | Float(_)
+                | Infer(
+                    InferTy::IntVar(_)
+                        | InferTy::FloatVar(_)
+                        | InferTy::FreshIntTy(_)
+                        | InferTy::FreshFloatTy(_)
+                )
         )
     }
 

compiler/rustc_middle/src/ty/error.rs

@@ -646,11 +646,14 @@ impl<T> Trait<T> for X {
         let current_method_ident = body_owner.and_then(|n| n.ident()).map(|i| i.name);
 
         // We don't want to suggest calling an assoc fn in a scope where that isn't feasible.
-        let callable_scope = matches!(body_owner, Some(
+        let callable_scope = matches!(
+            body_owner,
+            Some(
                 hir::Node::Item(hir::Item { kind: hir::ItemKind::Fn(..), .. })
-                | hir::Node::TraitItem(hir::TraitItem { kind: hir::TraitItemKind::Fn(..), .. })
-                | hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Fn(..), .. }),
-            ));
+                    | hir::Node::TraitItem(hir::TraitItem { kind: hir::TraitItemKind::Fn(..), .. })
+                    | hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Fn(..), .. }),
+            )
+        );
         let impl_comparison = matches!(
             cause_code,
             ObligationCauseCode::CompareImplMethodObligation { .. }

compiler/rustc_middle/src/ty/mod.rs

@@ -661,11 +661,28 @@ pub type RootVariableMinCaptureList<'tcx> = FxIndexMap<hir::HirId, MinCaptureLis
 /// Part of `MinCaptureInformationMap`; List of `CapturePlace`s.
 pub type MinCaptureList<'tcx> = Vec<CapturedPlace<'tcx>>;
 
-/// A `Place` and the corresponding `CaptureInfo`.
+/// A composite describing a `Place` that is captured by a closure.
 #[derive(PartialEq, Clone, Debug, TyEncodable, TyDecodable, TypeFoldable, HashStable)]
 pub struct CapturedPlace<'tcx> {
+    /// The `Place` that is captured.
     pub place: HirPlace<'tcx>,
+
+    /// `CaptureKind` and expression(s) that resulted in such capture of `place`.
     pub info: CaptureInfo<'tcx>,
+
+    /// Represents if `place` can be mutated or not.
+    pub mutability: hir::Mutability,
+}
+
+impl CapturedPlace<'tcx> {
+    /// Returns the hir-id of the root variable for the captured place.
+    /// e.g., if `a.b.c` was captured, would return the hir-id for `a`.
+    pub fn get_root_variable(&self) -> hir::HirId {
+        match self.place.base {
+            HirPlaceBase::Upvar(upvar_id) => upvar_id.var_path.hir_id,
+            base => bug!("Expected upvar, found={:?}", base),
+        }
+    }
 }
 
 pub fn place_to_string_for_capture(tcx: TyCtxt<'tcx>, place: &HirPlace<'tcx>) -> String {

compiler/rustc_middle/src/ty/relate.rs

@@ -33,15 +33,6 @@ pub trait TypeRelation<'tcx>: Sized {
     /// relation. Just affects error messages.
     fn a_is_expected(&self) -> bool;
 
-    /// Whether we should look into the substs of unevaluated constants
-    /// even if `feature(const_evaluatable_checked)` is active.
-    ///
-    /// This is needed in `combine` to prevent accidentially creating
-    /// infinite types as we abuse `TypeRelation` to walk a type there.
-    fn visit_ct_substs(&self) -> bool {
-        false
-    }
-
     fn with_cause<F, R>(&mut self, _cause: Cause, f: F) -> R
     where
         F: FnOnce(&mut Self) -> R,
@@ -588,7 +579,7 @@ pub fn super_relate_consts<R: TypeRelation<'tcx>>(
         (
             ty::ConstKind::Unevaluated(a_def, a_substs, None),
             ty::ConstKind::Unevaluated(b_def, b_substs, None),
-        ) if tcx.features().const_evaluatable_checked && !relation.visit_ct_substs() => {
+        ) if tcx.features().const_evaluatable_checked => {
             if tcx.try_unify_abstract_consts(((a_def, a_substs), (b_def, b_substs))) {
                 Ok(a.val)
             } else {

compiler/rustc_middle/src/ty/sty.rs

@@ -1871,8 +1871,14 @@ impl<'tcx> TyS<'tcx> {
     pub fn is_scalar(&self) -> bool {
         matches!(
             self.kind(),
-            Bool | Char | Int(_) | Float(_) | Uint(_) | FnDef(..) | FnPtr(_) | RawPtr(_)
-            | Infer(IntVar(_) | FloatVar(_))
+            Bool | Char
+                | Int(_)
+                | Float(_)
+                | Uint(_)
+                | FnDef(..)
+                | FnPtr(_)
+                | RawPtr(_)
+                | Infer(IntVar(_) | FloatVar(_))
         )
     }
 

compiler/rustc_mir/src/borrow_check/diagnostics/mod.rs

@@ -215,6 +215,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             PlaceRef { local, projection: [proj_base @ .., elem] } => {
                 match elem {
                     ProjectionElem::Deref => {
+                        // FIXME(project-rfc_2229#36): print capture precisely here.
                         let upvar_field_projection = self.is_upvar_field_projection(place);
                         if let Some(field) = upvar_field_projection {
                             let var_index = field.index();
@@ -259,6 +260,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     ProjectionElem::Field(field, _ty) => {
                         autoderef = true;
 
+                        // FIXME(project-rfc_2229#36): print capture precisely here.
                         let upvar_field_projection = self.is_upvar_field_projection(place);
                         if let Some(field) = upvar_field_projection {
                             let var_index = field.index();

compiler/rustc_mir/src/borrow_check/diagnostics/move_errors.rs

@@ -345,7 +345,9 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 };
 
                 let upvar = &self.upvars[upvar_field.unwrap().index()];
-                let upvar_hir_id = upvar.var_hir_id;
+                // FIXME(project-rfc-2229#8): Improve borrow-check diagnostics in case of precise
+                //                            capture.
+                let upvar_hir_id = upvar.place.get_root_variable();
                 let upvar_name = upvar.name;
                 let upvar_span = self.infcx.tcx.hir().span(upvar_hir_id);