Box `CanonicalUserTypeAnnotation::CanonicalUserType`.

This shrinks `Ascription`, which shrinks `PatKind::AscribeUserType`,
which shrinks `Pat`.

compiler/rustc_middle/src/thir.rs

@@ -809,8 +809,8 @@ mod size_asserts {
     static_assert_size!(Block, 56);
     static_assert_size!(Expr<'_>, 64);
     static_assert_size!(ExprKind<'_>, 40);
-    static_assert_size!(Pat<'_>, 112);
-    static_assert_size!(PatKind<'_>, 96);
+    static_assert_size!(Pat<'_>, 80);
+    static_assert_size!(PatKind<'_>, 64);
     static_assert_size!(Stmt<'_>, 56);
     static_assert_size!(StmtKind<'_>, 48);
 }

compiler/rustc_middle/src/ty/context.rs

@@ -874,7 +874,7 @@ pub struct UserTypeAnnotationIndex {
 
 #[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable, Lift)]
 pub struct CanonicalUserTypeAnnotation<'tcx> {
-    pub user_ty: CanonicalUserType<'tcx>,
+    pub user_ty: Box<CanonicalUserType<'tcx>>,
     pub span: Span,
     pub inferred_ty: Ty<'tcx>,
 }

compiler/rustc_mir_build/src/build/expr/as_constant.rs

@@ -42,10 +42,10 @@ pub(crate) fn as_constant(&mut self, expr: &Expr<'tcx>) -> Constant<'tcx> {
                 Constant { span, user_ty: None, literal }
             }
             ExprKind::NonHirLiteral { lit, ref user_ty } => {
-                let user_ty = user_ty.as_ref().map(|box user_ty| {
+                let user_ty = user_ty.as_ref().map(|user_ty| {
                     this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation {
                         span,
-                        user_ty: *user_ty,
+                        user_ty: user_ty.clone(),
                         inferred_ty: ty,
                     })
                 });
@@ -54,10 +54,10 @@ pub(crate) fn as_constant(&mut self, expr: &Expr<'tcx>) -> Constant<'tcx> {
                 Constant { span, user_ty: user_ty, literal }
             }
             ExprKind::ZstLiteral { ref user_ty } => {
-                let user_ty = user_ty.as_ref().map(|box user_ty| {
+                let user_ty = user_ty.as_ref().map(|user_ty| {
                     this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation {
                         span,
-                        user_ty: *user_ty,
+                        user_ty: user_ty.clone(),
                         inferred_ty: ty,
                     })
                 });
@@ -66,10 +66,10 @@ pub(crate) fn as_constant(&mut self, expr: &Expr<'tcx>) -> Constant<'tcx> {
                 Constant { span, user_ty: user_ty, literal }
             }
             ExprKind::NamedConst { def_id, substs, ref user_ty } => {
-                let user_ty = user_ty.as_ref().map(|box user_ty| {
+                let user_ty = user_ty.as_ref().map(|user_ty| {
                     this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation {
                         span,
-                        user_ty: *user_ty,
+                        user_ty: user_ty.clone(),
                         inferred_ty: ty,
                     })
                 });

compiler/rustc_mir_build/src/build/expr/as_place.rs

@@ -522,11 +522,11 @@ fn expr_as_place(
                         fake_borrow_temps,
                     )
                 );
-                if let Some(box user_ty) = user_ty {
+                if let Some(user_ty) = user_ty {
                     let annotation_index =
                         this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation {
                             span: source_info.span,
-                            user_ty: *user_ty,
+                            user_ty: user_ty.clone(),
                             inferred_ty: expr.ty,
                         });
 
@@ -551,11 +551,11 @@ fn expr_as_place(
                 let source = &this.thir[source];
                 let temp =
                     unpack!(block = this.as_temp(block, source.temp_lifetime, source, mutability));
-                if let Some(box user_ty) = user_ty {
+                if let Some(user_ty) = user_ty {
                     let annotation_index =
                         this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation {
                             span: source_info.span,
-                            user_ty: *user_ty,
+                            user_ty: user_ty.clone(),
                             inferred_ty: expr.ty,
                         });
                     this.cfg.push(

compiler/rustc_mir_build/src/build/expr/into.rs

@@ -378,10 +378,10 @@ pub(crate) fn expr_into_dest(
                 };
 
                 let inferred_ty = expr.ty;
-                let user_ty = user_ty.as_ref().map(|box user_ty| {
+                let user_ty = user_ty.as_ref().map(|user_ty| {
                     this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation {
                         span: source_info.span,
-                        user_ty: *user_ty,
+                        user_ty: user_ty.clone(),
                         inferred_ty,
                     })
                 });

compiler/rustc_mir_build/src/thir/cx/block.rs

@@ -87,7 +87,7 @@ fn mirror_stmts(
                             {
                                 debug!("mirror_stmts: user_ty={:?}", user_ty);
                                 let annotation = CanonicalUserTypeAnnotation {
-                                    user_ty,
+                                    user_ty: Box::new(user_ty),
                                     span: ty.span,
                                     inferred_ty: self.typeck_results.node_type(ty.hir_id),
                                 };

compiler/rustc_mir_build/src/thir/pattern/mod.rs

@@ -443,7 +443,7 @@ fn lower_variant_or_leaf(
         if let Some(user_ty) = self.user_substs_applied_to_ty_of_hir_id(hir_id) {
             debug!("lower_variant_or_leaf: kind={:?} user_ty={:?} span={:?}", kind, user_ty, span);
             let annotation = CanonicalUserTypeAnnotation {
-                user_ty,
+                user_ty: Box::new(user_ty),
                 span,
                 inferred_ty: self.typeck_results.node_type(hir_id),
             };
@@ -512,7 +512,7 @@ fn lower_path(&mut self, qpath: &hir::QPath<'_>, id: hir::HirId, span: Span) ->
                 let user_provided_types = self.typeck_results().user_provided_types();
                 if let Some(&user_ty) = user_provided_types.get(id) {
                     let annotation = CanonicalUserTypeAnnotation {
-                        user_ty,
+                        user_ty: Box::new(user_ty),
                         span,
                         inferred_ty: self.typeck_results().node_type(id),
                     };