Remove box syntax from rustc_mir_dataflow and rustc_mir_transform

Author: est31

compiler/rustc_mir_dataflow/src/lib.rs

@@ -1,6 +1,5 @@
 #![feature(associated_type_defaults)]
 #![feature(box_patterns)]
-#![feature(box_syntax)]
 #![feature(exact_size_is_empty)]
 #![feature(let_else)]
 #![feature(min_specialization)]

compiler/rustc_mir_transform/src/instcombine.rs

@@ -192,12 +192,12 @@ impl<'tcx> InstCombineContext<'tcx, '_> {
 
         statements.push(Statement {
             source_info: terminator.source_info,
-            kind: StatementKind::Assign(box (
+            kind: StatementKind::Assign(Box::new((
                 destination_place,
                 Rvalue::Use(Operand::Copy(
                     arg_place.project_deeper(&[ProjectionElem::Deref], self.tcx),
                 )),
-            )),
+            ))),
         });
         terminator.kind = TerminatorKind::Goto { target: destination_block };
     }

compiler/rustc_mir_transform/src/lib.rs

@@ -1,6 +1,5 @@
 #![allow(rustc::potential_query_instability)]
 #![feature(box_patterns)]
-#![feature(box_syntax)]
 #![feature(let_chains)]
 #![feature(let_else)]
 #![feature(map_try_insert)]

compiler/rustc_mir_transform/src/normalize_array_len.rs

@@ -125,7 +125,7 @@ impl<'tcx> Patcher<'_, 'tcx> {
                             let assign_to = Place::from(local);
                             let rvalue = Rvalue::Use(operand);
                             make_copy_statement.kind =
-                                StatementKind::Assign(box (assign_to, rvalue));
+                                StatementKind::Assign(Box::new((assign_to, rvalue)));
                             statements.push(make_copy_statement);
 
                             // to reorder we have to copy and make NOP
@@ -165,7 +165,8 @@ impl<'tcx> Patcher<'_, 'tcx> {
                     if add_deref {
                         place = self.tcx.mk_place_deref(place);
                     }
-                    len_statement.kind = StatementKind::Assign(box (*into, Rvalue::Len(place)));
+                    len_statement.kind =
+                        StatementKind::Assign(Box::new((*into, Rvalue::Len(place))));
                     statements.push(len_statement);
 
                     // make temporary dead