Rollup of 4 pull requests

compiler/rustc_ast/src/ast.rs

@@ -3126,6 +3126,35 @@ pub struct StaticItem {
     pub expr: Option<P<Expr>>,
 }
 
+/// A static item in `extern` block.
+// This struct is identical to StaticItem for now but it's going to have a safety attribute.
+#[derive(Clone, Encodable, Decodable, Debug)]
+pub struct StaticForeignItem {
+    pub ty: P<Ty>,
+    pub mutability: Mutability,
+    pub expr: Option<P<Expr>>,
+}
+
+impl From<StaticItem> for StaticForeignItem {
+    fn from(static_item: StaticItem) -> StaticForeignItem {
+        StaticForeignItem {
+            ty: static_item.ty,
+            mutability: static_item.mutability,
+            expr: static_item.expr,
+        }
+    }
+}
+
+impl From<StaticForeignItem> for StaticItem {
+    fn from(static_item: StaticForeignItem) -> StaticItem {
+        StaticItem {
+            ty: static_item.ty,
+            mutability: static_item.mutability,
+            expr: static_item.expr,
+        }
+    }
+}
+
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub struct ConstItem {
     pub defaultness: Defaultness,
@@ -3329,7 +3358,7 @@ impl TryFrom<ItemKind> for AssocItemKind {
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub enum ForeignItemKind {
     /// A foreign static item (`static FOO: u8`).
-    Static(P<Ty>, Mutability, Option<P<Expr>>),
+    Static(Box<StaticForeignItem>),
     /// An foreign function.
     Fn(Box<Fn>),
     /// An foreign type.
@@ -3341,8 +3370,8 @@ pub enum ForeignItemKind {
 impl From<ForeignItemKind> for ItemKind {
     fn from(foreign_item_kind: ForeignItemKind) -> ItemKind {
         match foreign_item_kind {
-            ForeignItemKind::Static(a, b, c) => {
-                ItemKind::Static(StaticItem { ty: a, mutability: b, expr: c }.into())
+            ForeignItemKind::Static(box static_foreign_item) => {
+                ItemKind::Static(Box::new(static_foreign_item.into()))
             }
             ForeignItemKind::Fn(fn_kind) => ItemKind::Fn(fn_kind),
             ForeignItemKind::TyAlias(ty_alias_kind) => ItemKind::TyAlias(ty_alias_kind),
@@ -3356,8 +3385,8 @@ impl TryFrom<ItemKind> for ForeignItemKind {
 
     fn try_from(item_kind: ItemKind) -> Result<ForeignItemKind, ItemKind> {
         Ok(match item_kind {
-            ItemKind::Static(box StaticItem { ty: a, mutability: b, expr: c }) => {
-                ForeignItemKind::Static(a, b, c)
+            ItemKind::Static(box static_item) => {
+                ForeignItemKind::Static(Box::new(static_item.into()))
             }
             ItemKind::Fn(fn_kind) => ForeignItemKind::Fn(fn_kind),
             ItemKind::TyAlias(ty_alias_kind) => ForeignItemKind::TyAlias(ty_alias_kind),
@@ -3382,8 +3411,8 @@ mod size_asserts {
     static_assert_size!(Expr, 72);
     static_assert_size!(ExprKind, 40);
     static_assert_size!(Fn, 160);
-    static_assert_size!(ForeignItem, 96);
-    static_assert_size!(ForeignItemKind, 24);
+    static_assert_size!(ForeignItem, 88);
+    static_assert_size!(ForeignItemKind, 16);
     static_assert_size!(GenericArg, 24);
     static_assert_size!(GenericBound, 88);
     static_assert_size!(Generics, 40);

compiler/rustc_ast/src/mut_visit.rs

@@ -1261,7 +1261,7 @@ pub fn noop_flat_map_item<K: NoopVisitItemKind>(
 impl NoopVisitItemKind for ForeignItemKind {
     fn noop_visit(&mut self, visitor: &mut impl MutVisitor) {
         match self {
-            ForeignItemKind::Static(ty, _, expr) => {
+            ForeignItemKind::Static(box StaticForeignItem { ty, mutability: _, expr }) => {
                 visitor.visit_ty(ty);
                 visit_opt(expr, |expr| visitor.visit_expr(expr));
             }

compiler/rustc_ast/src/visit.rs

@@ -642,7 +642,7 @@ impl WalkItemKind for ForeignItemKind {
     ) -> V::Result {
         let &Item { id, span, ident, ref vis, .. } = item;
         match self {
-            ForeignItemKind::Static(ty, _, expr) => {
+            ForeignItemKind::Static(box StaticForeignItem { ty, mutability: _, expr }) => {
                 try_visit!(visitor.visit_ty(ty));
                 visit_opt!(visitor, visit_expr, expr);
             }

compiler/rustc_ast_lowering/src/item.rs

@@ -662,10 +662,10 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
                     hir::ForeignItemKind::Fn(fn_dec, fn_args, generics)
                 }
-                ForeignItemKind::Static(t, m, _) => {
-                    let ty =
-                        self.lower_ty(t, ImplTraitContext::Disallowed(ImplTraitPosition::StaticTy));
-                    hir::ForeignItemKind::Static(ty, *m)
+                ForeignItemKind::Static(box StaticForeignItem { ty, mutability, expr: _ }) => {
+                    let ty = self
+                        .lower_ty(ty, ImplTraitContext::Disallowed(ImplTraitPosition::StaticTy));
+                    hir::ForeignItemKind::Static(ty, *mutability)
                 }
                 ForeignItemKind::TyAlias(..) => hir::ForeignItemKind::Type,
                 ForeignItemKind::MacCall(_) => panic!("macro shouldn't exist here"),

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -1185,8 +1185,8 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                 self.check_foreign_ty_genericless(generics, where_clauses);
                 self.check_foreign_item_ascii_only(fi.ident);
             }
-            ForeignItemKind::Static(_, _, body) => {
-                self.check_foreign_kind_bodyless(fi.ident, "static", body.as_ref().map(|b| b.span));
+            ForeignItemKind::Static(box StaticForeignItem { ty: _, mutability: _, expr }) => {
+                self.check_foreign_kind_bodyless(fi.ident, "static", expr.as_ref().map(|b| b.span));
                 self.check_foreign_item_ascii_only(fi.ident);
             }
             ForeignItemKind::MacCall(..) => {}

compiler/rustc_ast_pretty/src/pprust/state/item.rs

@@ -30,15 +30,17 @@ impl<'a> State<'a> {
             ast::ForeignItemKind::Fn(box ast::Fn { defaultness, sig, generics, body }) => {
                 self.print_fn_full(sig, ident, generics, vis, *defaultness, body.as_deref(), attrs);
             }
-            ast::ForeignItemKind::Static(ty, mutbl, body) => self.print_item_const(
-                ident,
-                Some(*mutbl),
-                &ast::Generics::default(),
-                ty,
-                body.as_deref(),
-                vis,
-                ast::Defaultness::Final,
-            ),
+            ast::ForeignItemKind::Static(box ast::StaticForeignItem { ty, mutability, expr }) => {
+                self.print_item_const(
+                    ident,
+                    Some(*mutability),
+                    &ast::Generics::default(),
+                    ty,
+                    expr.as_deref(),
+                    vis,
+                    ast::Defaultness::Final,
+                )
+            }
             ast::ForeignItemKind::TyAlias(box ast::TyAlias {
                 defaultness,
                 generics,

compiler/rustc_middle/src/traits/solve/inspect.rs

@@ -60,14 +60,14 @@ pub struct GoalEvaluation<'tcx> {
     pub evaluation: CanonicalGoalEvaluation<'tcx>,
 }
 
-#[derive(Eq, PartialEq)]
+#[derive(Eq, PartialEq, Debug)]
 pub struct CanonicalGoalEvaluation<'tcx> {
     pub goal: CanonicalInput<'tcx>,
     pub kind: CanonicalGoalEvaluationKind<'tcx>,
     pub result: QueryResult<'tcx>,
 }
 
-#[derive(Eq, PartialEq)]
+#[derive(Eq, PartialEq, Debug)]
 pub enum CanonicalGoalEvaluationKind<'tcx> {
     Overflow,
     CycleInStack,
@@ -86,7 +86,7 @@ pub struct AddedGoalsEvaluation<'tcx> {
     pub result: Result<Certainty, NoSolution>,
 }
 
-#[derive(Eq, PartialEq)]
+#[derive(Eq, PartialEq, Debug)]
 pub struct GoalEvaluationStep<'tcx> {
     pub instantiated_goal: QueryInput<'tcx, ty::Predicate<'tcx>>,
 

compiler/rustc_parse/src/parser/item.rs

@@ -1191,7 +1191,11 @@ impl<'a> Parser<'a> {
                                 ident_span: ident.span,
                                 const_span,
                             });
-                            ForeignItemKind::Static(ty, Mutability::Not, expr)
+                            ForeignItemKind::Static(Box::new(StaticForeignItem {
+                                ty,
+                                mutability: Mutability::Not,
+                                expr,
+                            }))
                         }
                         _ => return self.error_bad_item_kind(span, &kind, "`extern` blocks"),
                     },

compiler/rustc_resolve/src/def_collector.rs

@@ -209,7 +209,7 @@ impl<'a, 'b, 'tcx> visit::Visitor<'a> for DefCollector<'a, 'b, 'tcx> {
 
     fn visit_foreign_item(&mut self, fi: &'a ForeignItem) {
         let def_kind = match fi.kind {
-            ForeignItemKind::Static(_, mutability, _) => {
+            ForeignItemKind::Static(box StaticForeignItem { ty: _, mutability, expr: _ }) => {
                 DefKind::Static { mutability, nested: false }
             }
             ForeignItemKind::Fn(_) => DefKind::Fn,

compiler/rustc_trait_selection/src/solve/inspect/analyse.rs

@@ -34,9 +34,9 @@ pub struct InspectConfig {
 pub struct InspectGoal<'a, 'tcx> {
     infcx: &'a InferCtxt<'tcx>,
     depth: usize,
-    orig_values: &'a [ty::GenericArg<'tcx>],
+    orig_values: Vec<ty::GenericArg<'tcx>>,
     goal: Goal<'tcx, ty::Predicate<'tcx>>,
-    evaluation: &'a inspect::GoalEvaluation<'tcx>,
+    evaluation: inspect::CanonicalGoalEvaluation<'tcx>,
 }
 
 pub struct InspectCandidate<'a, 'tcx> {
@@ -57,6 +57,10 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> {
         self.result.map(|c| c.value.certainty)
     }
 
+    pub fn goal(&self) -> &'a InspectGoal<'a, 'tcx> {
+        self.goal
+    }
+
     /// Certainty passed into `evaluate_added_goals_and_make_canonical_response`.
     ///
     /// If this certainty is `Yes`, then we must be confident that the candidate
@@ -74,46 +78,55 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> {
     /// the state of the `infcx`.
     pub fn visit_nested_no_probe<V: ProofTreeVisitor<'tcx>>(&self, visitor: &mut V) -> V::Result {
         if self.goal.depth < visitor.config().max_depth {
-            let infcx = self.goal.infcx;
-            let param_env = self.goal.goal.param_env;
-            let mut orig_values = self.goal.orig_values.to_vec();
-            let mut instantiated_goals = vec![];
-            for goal in &self.nested_goals {
-                let goal = canonical::instantiate_canonical_state(
+            for goal in self.instantiate_nested_goals(visitor.span()) {
+                try_visit!(visitor.visit_goal(&goal));
+            }
+        }
+
+        V::Result::output()
+    }
+
+    /// Instantiate the nested goals for the candidate without rolling back their
+    /// inference constraints. This function modifies the state of the `infcx`.
+    pub fn instantiate_nested_goals(&self, span: Span) -> Vec<InspectGoal<'a, 'tcx>> {
+        let infcx = self.goal.infcx;
+        let param_env = self.goal.goal.param_env;
+        let mut orig_values = self.goal.orig_values.to_vec();
+        let instantiated_goals: Vec<_> = self
+            .nested_goals
+            .iter()
+            .map(|goal| {
+                canonical::instantiate_canonical_state(
                     infcx,
-                    visitor.span(),
+                    span,
                     param_env,
                     &mut orig_values,
                     *goal,
-                );
-                instantiated_goals.push(goal);
-            }
+                )
+            })
+            .collect();
 
-            let () = canonical::instantiate_canonical_state(
-                infcx,
-                visitor.span(),
-                param_env,
-                &mut orig_values,
-                self.final_state,
-            );
+        let () = canonical::instantiate_canonical_state(
+            infcx,
+            span,
+            param_env,
+            &mut orig_values,
+            self.final_state,
+        );
 
-            for &goal in &instantiated_goals {
+        instantiated_goals
+            .into_iter()
+            .map(|goal| {
                 let proof_tree = match goal.predicate.kind().no_bound_vars() {
                     Some(ty::PredicateKind::NormalizesTo(ty::NormalizesTo { alias, term })) => {
                         let unconstrained_term = match term.unpack() {
                             ty::TermKind::Ty(_) => infcx
-                                .next_ty_var(TypeVariableOrigin {
-                                    param_def_id: None,
-                                    span: visitor.span(),
-                                })
+                                .next_ty_var(TypeVariableOrigin { param_def_id: None, span })
                                 .into(),
                             ty::TermKind::Const(ct) => infcx
                                 .next_const_var(
                                     ct.ty(),
-                                    ConstVariableOrigin {
-                                        param_def_id: None,
-                                        span: visitor.span(),
-                                    },
+                                    ConstVariableOrigin { param_def_id: None, span },
                                 )
                                 .into(),
                         };
@@ -129,22 +142,16 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> {
                             })
                             .1;
                         let InferOk { value: (), obligations: _ } = infcx
-                            .at(&ObligationCause::dummy(), param_env)
+                            .at(&ObligationCause::dummy_with_span(span), param_env)
                             .eq(DefineOpaqueTypes::Yes, term, unconstrained_term)
                             .unwrap();
                         proof_tree
                     }
                     _ => infcx.evaluate_root_goal(goal, GenerateProofTree::Yes).1,
                 };
-                try_visit!(visitor.visit_goal(&InspectGoal::new(
-                    infcx,
-                    self.goal.depth + 1,
-                    &proof_tree.unwrap(),
-                )));
-            }
-        }
-
-        V::Result::output()
+                InspectGoal::new(infcx, self.goal.depth + 1, proof_tree.unwrap())
+            })
+            .collect()
     }
 
     /// Visit all nested goals of this candidate, rolling back
@@ -164,7 +171,7 @@ impl<'a, 'tcx> InspectGoal<'a, 'tcx> {
     }
 
     pub fn result(&self) -> Result<Certainty, NoSolution> {
-        self.evaluation.evaluation.result.map(|c| c.value.certainty)
+        self.evaluation.result.map(|c| c.value.certainty)
     }
 
     fn candidates_recur(
@@ -221,7 +228,7 @@ impl<'a, 'tcx> InspectGoal<'a, 'tcx> {
 
     pub fn candidates(&'a self) -> Vec<InspectCandidate<'a, 'tcx>> {
         let mut candidates = vec![];
-        let last_eval_step = match self.evaluation.evaluation.kind {
+        let last_eval_step = match self.evaluation.kind {
             inspect::CanonicalGoalEvaluationKind::Overflow
             | inspect::CanonicalGoalEvaluationKind::CycleInStack
             | inspect::CanonicalGoalEvaluationKind::ProvisionalCacheHit => {
@@ -254,18 +261,15 @@ impl<'a, 'tcx> InspectGoal<'a, 'tcx> {
         candidates.pop().filter(|_| candidates.is_empty())
     }
 
-    fn new(
-        infcx: &'a InferCtxt<'tcx>,
-        depth: usize,
-        root: &'a inspect::GoalEvaluation<'tcx>,
-    ) -> Self {
-        match root.kind {
-            inspect::GoalEvaluationKind::Root { ref orig_values } => InspectGoal {
+    fn new(infcx: &'a InferCtxt<'tcx>, depth: usize, root: inspect::GoalEvaluation<'tcx>) -> Self {
+        let inspect::GoalEvaluation { uncanonicalized_goal, kind, evaluation } = root;
+        match kind {
+            inspect::GoalEvaluationKind::Root { orig_values } => InspectGoal {
                 infcx,
                 depth,
                 orig_values,
-                goal: root.uncanonicalized_goal.fold_with(&mut EagerResolver::new(infcx)),
-                evaluation: root,
+                goal: uncanonicalized_goal.fold_with(&mut EagerResolver::new(infcx)),
+                evaluation,
             },
             inspect::GoalEvaluationKind::Nested { .. } => unreachable!(),
         }
@@ -294,6 +298,6 @@ impl<'tcx> InferCtxt<'tcx> {
     ) -> V::Result {
         let (_, proof_tree) = self.evaluate_root_goal(goal, GenerateProofTree::Yes);
         let proof_tree = proof_tree.unwrap();
-        visitor.visit_goal(&InspectGoal::new(self, 0, &proof_tree))
+        visitor.visit_goal(&InspectGoal::new(self, 0, proof_tree))
     }
 }

src/tools/clippy/clippy_utils/src/ast_utils.rs

@@ -446,7 +446,18 @@ pub fn eq_item_kind(l: &ItemKind, r: &ItemKind) -> bool {
 pub fn eq_foreign_item_kind(l: &ForeignItemKind, r: &ForeignItemKind) -> bool {
     use ForeignItemKind::*;
     match (l, r) {
-        (Static(lt, lm, le), Static(rt, rm, re)) => lm == rm && eq_ty(lt, rt) && eq_expr_opt(le, re),
+        (
+            Static(box StaticForeignItem {
+                ty: lt,
+                mutability: lm,
+                expr: le,
+            }),
+            Static(box StaticForeignItem {
+                ty: rt,
+                mutability: rm,
+                expr: re,
+            }),
+        ) => lm == rm && eq_ty(lt, rt) && eq_expr_opt(le, re),
         (
             Fn(box ast::Fn {
                 defaultness: ld,