Make ExprKind::Closure a struct variant.

compiler/rustc_passes/src/check_attr.rs

@@ -2340,7 +2340,7 @@ impl<'tcx> Visitor<'tcx> for CheckAttrVisitor<'tcx> {
 
     fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
         let target = match expr.kind {
-            hir::ExprKind::Closure(..) => Target::Closure,
+            hir::ExprKind::Closure { .. } => Target::Closure,
             _ => Target::Expression,
         };
 

compiler/rustc_passes/src/liveness.rs

@@ -405,7 +405,7 @@ impl<'tcx> Visitor<'tcx> for IrMaps<'tcx> {
                 }
                 intravisit::walk_expr(self, expr);
             }
-            hir::ExprKind::Closure(..) => {
+            hir::ExprKind::Closure { .. } => {
                 // Interesting control flow (for loops can contain labeled
                 // breaks or continues)
                 self.add_live_node_for_node(expr.hir_id, ExprNode(expr.span, expr.hir_id));
@@ -833,7 +833,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
 
             hir::ExprKind::Field(ref e, _) => self.propagate_through_expr(&e, succ),
 
-            hir::ExprKind::Closure(..) => {
+            hir::ExprKind::Closure { .. } => {
                 debug!("{:?} is an ExprKind::Closure", expr);
 
                 // the construction of a closure itself is not important,
@@ -1387,7 +1387,7 @@ fn check_expr<'tcx>(this: &mut Liveness<'_, 'tcx>, expr: &'tcx Expr<'tcx>) {
         | hir::ExprKind::AddrOf(..)
         | hir::ExprKind::Struct(..)
         | hir::ExprKind::Repeat(..)
-        | hir::ExprKind::Closure(..)
+        | hir::ExprKind::Closure { .. }
         | hir::ExprKind::Path(_)
         | hir::ExprKind::Yield(..)
         | hir::ExprKind::Box(..)

compiler/rustc_passes/src/loops.rs

@@ -57,14 +57,14 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
             hir::ExprKind::Loop(ref b, _, source, _) => {
                 self.with_context(Loop(source), |v| v.visit_block(&b));
             }
-            hir::ExprKind::Closure(_, ref function_decl, b, span, movability) => {
+            hir::ExprKind::Closure { ref fn_decl, body, fn_decl_span, movability, .. } => {
                 let cx = if let Some(Movability::Static) = movability {
-                    AsyncClosure(span)
+                    AsyncClosure(fn_decl_span)
                 } else {
-                    Closure(span)
+                    Closure(fn_decl_span)
                 };
-                self.visit_fn_decl(&function_decl);
-                self.with_context(cx, |v| v.visit_nested_body(b));
+                self.visit_fn_decl(&fn_decl);
+                self.with_context(cx, |v| v.visit_nested_body(body));
             }
             hir::ExprKind::Block(ref b, Some(_label)) => {
                 self.with_context(LabeledBlock, |v| v.visit_block(&b));

compiler/rustc_passes/src/naked_functions.rs

@@ -212,7 +212,7 @@ impl<'tcx> CheckInlineAssembly<'tcx> {
             | ExprKind::Loop(..)
             | ExprKind::Match(..)
             | ExprKind::If(..)
-            | ExprKind::Closure(..)
+            | ExprKind::Closure { .. }
             | ExprKind::Assign(..)
             | ExprKind::AssignOp(..)
             | ExprKind::Field(..)

compiler/rustc_passes/src/reachable.rs

@@ -273,7 +273,7 @@ impl<'tcx> ReachableContext<'tcx> {
                 }
                 hir::ImplItemKind::TyAlias(_) => {}
             },
-            Node::Expr(&hir::Expr { kind: hir::ExprKind::Closure(.., body, _, _), .. }) => {
+            Node::Expr(&hir::Expr { kind: hir::ExprKind::Closure { body, .. }, .. }) => {
                 self.visit_nested_body(body);
             }
             // Nothing to recurse on for these

compiler/rustc_passes/src/upvars.rs

@@ -75,7 +75,7 @@ impl<'tcx> Visitor<'tcx> for CaptureCollector<'_, 'tcx> {
     }
 
     fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
-        if let hir::ExprKind::Closure(..) = expr.kind {
+        if let hir::ExprKind::Closure { .. } = expr.kind {
             let closure_def_id = self.tcx.hir().local_def_id(expr.hir_id);
             if let Some(upvars) = self.tcx.upvars_mentioned(closure_def_id) {
                 // Every capture of a closure expression is a local in scope,