rust-lang · bors · Sep 25, 2015 · Sep 24, 2015
diff --git a/src/liballoc/boxed.rs b/src/liballoc/boxed.rs
@@ -80,11 +80,10 @@ use core::raw::{TraitObject};
 /// use std::boxed::HEAP;
 ///
 /// fn main() {
-///     let foo = box(HEAP) 5;
+///     let foo: Box<i32> = in HEAP { 5 };
 ///     let foo = box 5;
 /// }
 /// ```
-#[lang = "exchange_heap"]
 #[unstable(feature = "box_heap",
            reason = "may be renamed; uncertain about custom allocator design",
            issue = "27779")]

diff --git a/src/librustc/middle/cfg/construct.rs b/src/librustc/middle/cfg/construct.rs
@@ -344,13 +344,12 @@ impl<'a, 'tcx> CFGBuilder<'a, 'tcx> {
                 self.straightline(expr, pred, [r, l].iter().map(|&e| &**e))
             }
 
-            hir::ExprBox(Some(ref l), ref r) |
             hir::ExprIndex(ref l, ref r) |
             hir::ExprBinary(_, ref l, ref r) => { // NB: && and || handled earlier
                 self.straightline(expr, pred, [l, r].iter().map(|&e| &**e))
             }
 
-            hir::ExprBox(None, ref e) |
+            hir::ExprBox(ref e) |
             hir::ExprAddrOf(_, ref e) |
             hir::ExprCast(ref e, _) |
             hir::ExprUnary(_, ref e) |

diff --git a/src/librustc/middle/check_const.rs b/src/librustc/middle/check_const.rs
@@ -568,8 +568,7 @@ fn check_expr<'a, 'tcx>(v: &mut CheckCrateVisitor<'a, 'tcx>,
                             "user-defined operators are not allowed in {}s", v.msg());
             }
         }
-        hir::ExprBox(..) |
-        hir::ExprUnary(hir::UnUniq, _) => {
+        hir::ExprBox(_) => {
             v.add_qualif(ConstQualif::NOT_CONST);
             if v.mode != Mode::Var {
                 span_err!(v.tcx.sess, e.span, E0010,

diff --git a/src/librustc/middle/expr_use_visitor.rs b/src/librustc/middle/expr_use_visitor.rs
@@ -280,13 +280,11 @@ impl<'d,'t,'a,'tcx> ExprUseVisitor<'d,'t,'a,'tcx> {
                typer: &'t infer::InferCtxt<'a, 'tcx>)
                -> ExprUseVisitor<'d,'t,'a,'tcx>
     {
-        let result = ExprUseVisitor {
+        ExprUseVisitor {
             typer: typer,
             mc: mc::MemCategorizationContext::new(typer),
             delegate: delegate,
-        };
-
-        result
+        }
     }
 
     pub fn walk_fn(&mut self,
@@ -544,17 +542,8 @@ impl<'d,'t,'a,'tcx> ExprUseVisitor<'d,'t,'a,'tcx> {
                 self.walk_captures(expr)
             }
 
-            hir::ExprBox(ref place, ref base) => {
-                match *place {
-                    Some(ref place) => self.consume_expr(&**place),
-                    None => {}
-                }
+            hir::ExprBox(ref base) => {
                 self.consume_expr(&**base);
-                if place.is_some() {
-                    self.tcx().sess.span_bug(
-                        expr.span,
-                        "box with explicit place remains after expansion");
-                }
             }
         }
     }

diff --git a/src/librustc/middle/lang_items.rs b/src/librustc/middle/lang_items.rs
@@ -341,7 +341,6 @@ lets_do_this! {
     EhUnwindResumeLangItem,          "eh_unwind_resume",        eh_unwind_resume;
     MSVCTryFilterLangItem,           "msvc_try_filter",         msvc_try_filter;
 
-    ExchangeHeapLangItem,            "exchange_heap",           exchange_heap;
     OwnedBoxLangItem,                "owned_box",               owned_box;
 
     PhantomDataItem,                 "phantom_data",            phantom_data;

diff --git a/src/librustc/middle/liveness.rs b/src/librustc/middle/liveness.rs
@@ -1147,8 +1147,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
           }
 
           hir::ExprIndex(ref l, ref r) |
-          hir::ExprBinary(_, ref l, ref r) |
-          hir::ExprBox(Some(ref l), ref r) => {
+          hir::ExprBinary(_, ref l, ref r) => {
             let r_succ = self.propagate_through_expr(&**r, succ);
             self.propagate_through_expr(&**l, r_succ)
           }
@@ -1158,7 +1157,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
             e1.as_ref().map_or(succ, |e| self.propagate_through_expr(&**e, succ))
           }
 
-          hir::ExprBox(None, ref e) |
+          hir::ExprBox(ref e) |
           hir::ExprAddrOf(_, ref e) |
           hir::ExprCast(ref e, _) |
           hir::ExprUnary(_, ref e) => {

diff --git a/src/librustc/middle/region.rs b/src/librustc/middle/region.rs
@@ -994,9 +994,6 @@ fn resolve_local(visitor: &mut RegionResolutionVisitor, local: &hir::Local) {
                         visitor, &**subexpr, blk_id);
                 }
             }
-            hir::ExprUnary(hir::UnUniq, ref subexpr) => {
-                record_rvalue_scope_if_borrow_expr(visitor, &**subexpr, blk_id);
-            }
             hir::ExprCast(ref subexpr, _) => {
                 record_rvalue_scope_if_borrow_expr(visitor, &**subexpr, blk_id)
             }

diff --git a/src/librustc_front/fold.rs b/src/librustc_front/fold.rs
@@ -1040,8 +1040,8 @@ pub fn noop_fold_expr<T: Folder>(Expr {id, node, span}: Expr, folder: &mut T) ->
     Expr {
         id: folder.new_id(id),
         node: match node {
-            ExprBox(p, e) => {
-                ExprBox(p.map(|e|folder.fold_expr(e)), folder.fold_expr(e))
+            ExprBox(e) => {
+                ExprBox(folder.fold_expr(e))
             }
             ExprVec(exprs) => {
                 ExprVec(exprs.move_map(|x| folder.fold_expr(x)))

diff --git a/src/librustc_front/hir.rs b/src/librustc_front/hir.rs
@@ -491,8 +491,6 @@ pub type BinOp = Spanned<BinOp_>;
 
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug, Copy)]
 pub enum UnOp {
-    /// The `box` operator
-    UnUniq,
     /// The `*` operator for dereferencing
     UnDeref,
     /// The `!` operator for logical inversion
@@ -595,8 +593,8 @@ impl fmt::Debug for Expr {
 
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub enum Expr_ {
-    /// First expr is the place; second expr is the value.
-    ExprBox(Option<P<Expr>>, P<Expr>),
+    /// A `box x` expression.
+    ExprBox(P<Expr>),
     /// An array (`[a, b, c, d]`)
     ExprVec(Vec<P<Expr>>),
     /// A function call

diff --git a/src/librustc_front/lowering.rs b/src/librustc_front/lowering.rs
@@ -605,7 +605,6 @@ pub fn lower_constness(c: Constness) -> hir::Constness {
 
 pub fn lower_unop(u: UnOp) -> hir::UnOp {
     match u {
-        UnUniq => hir::UnUniq,
         UnDeref => hir::UnDeref,
         UnNot => hir::UnNot,
         UnNeg => hir::UnNeg,
@@ -694,8 +693,8 @@ pub fn lower_expr(e: &Expr) -> P<hir::Expr> {
     P(hir::Expr {
             id: e.id,
             node: match e.node {
-                ExprBox(ref p, ref e) => {
-                    hir::ExprBox(p.as_ref().map(|e| lower_expr(e)), lower_expr(e))
+                ExprBox(ref e) => {
+                    hir::ExprBox(lower_expr(e))
                 }
                 ExprVec(ref exprs) => {
                     hir::ExprVec(exprs.iter().map(|x| lower_expr(x)).collect())
@@ -818,6 +817,7 @@ pub fn lower_expr(e: &Expr) -> P<hir::Expr> {
                 ExprParen(ref ex) => {
                     return lower_expr(ex);
                 }
+                ExprInPlace(..) |
                 ExprIfLet(..) |
                 ExprWhileLet(..) |
                 ExprForLoop(..) |

diff --git a/src/librustc_front/print/pprust.rs b/src/librustc_front/print/pprust.rs
@@ -1182,16 +1182,6 @@ impl<'a> State<'a> {
         Ok(())
     }
 
-    fn print_expr_box(&mut self,
-                      place: &Option<P<hir::Expr>>,
-                      expr: &hir::Expr) -> io::Result<()> {
-        try!(word(&mut self.s, "box"));
-        try!(word(&mut self.s, "("));
-        try!(place.as_ref().map_or(Ok(()), |e|self.print_expr(&**e)));
-        try!(self.word_space(")"));
-        self.print_expr(expr)
-    }
-
     fn print_expr_vec(&mut self, exprs: &[P<hir::Expr>]) -> io::Result<()> {
         try!(self.ibox(indent_unit));
         try!(word(&mut self.s, "["));
@@ -1311,8 +1301,9 @@ impl<'a> State<'a> {
         try!(self.ibox(indent_unit));
         try!(self.ann.pre(self, NodeExpr(expr)));
         match expr.node {
-            hir::ExprBox(ref place, ref expr) => {
-                try!(self.print_expr_box(place, &**expr));
+            hir::ExprBox(ref expr) => {
+                try!(self.word_space("box"));
+                try!(self.print_expr(expr));
             }
             hir::ExprVec(ref exprs) => {
                 try!(self.print_expr_vec(&exprs[..]));

diff --git a/src/librustc_front/util.rs b/src/librustc_front/util.rs
@@ -128,10 +128,9 @@ pub fn is_by_value_unop(u: UnOp) -> bool {
 
 pub fn unop_to_string(op: UnOp) -> &'static str {
     match op {
-      UnUniq => "box() ",
-      UnDeref => "*",
-      UnNot => "!",
-      UnNeg => "-",
+        UnDeref => "*",
+        UnNot => "!",
+        UnNeg => "-",
     }
 }
 

diff --git a/src/librustc_front/visit.rs b/src/librustc_front/visit.rs
@@ -722,8 +722,7 @@ pub fn walk_exprs<'v, V: Visitor<'v>>(visitor: &mut V, expressions: &'v [P<Expr>
 
 pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr) {
     match expression.node {
-        ExprBox(ref place, ref subexpression) => {
-            place.as_ref().map(|e|visitor.visit_expr(&**e));
+        ExprBox(ref subexpression) => {
             visitor.visit_expr(&**subexpression)
         }
         ExprVec(ref subexpressions) => {

diff --git a/src/librustc_lint/unused.rs b/src/librustc_lint/unused.rs
@@ -442,7 +442,7 @@ impl LintPass for UnusedAllocation {
 impl LateLintPass for UnusedAllocation {
     fn check_expr(&mut self, cx: &LateContext, e: &hir::Expr) {
         match e.node {
-            hir::ExprUnary(hir::UnUniq, _) => (),
+            hir::ExprBox(_) => {}
             _ => return
         }
 

diff --git a/src/librustc_mir/build/expr/as_rvalue.rs b/src/librustc_mir/build/expr/as_rvalue.rs
@@ -67,7 +67,7 @@ impl<H:Hair> Builder<H> {
                 let arg = unpack!(block = this.as_operand(block, arg));
                 block.and(Rvalue::UnaryOp(op, arg))
             }
-            ExprKind::Box { place: _, value } => {
+            ExprKind::Box { value } => {
                 let value = this.hir.mirror(value);
                 let value_ty = value.ty.clone();
                 let result = this.temp(value_ty.clone());

diff --git a/src/librustc_mir/hair.rs b/src/librustc_mir/hair.rs
@@ -171,7 +171,7 @@ pub struct Expr<H:Hair> {
 #[derive(Clone, Debug)]
 pub enum ExprKind<H:Hair> {
     Scope { extent: H::CodeExtent, value: ExprRef<H> },
-    Box { place: Option<ExprRef<H>>, value: ExprRef<H> },
+    Box { value: ExprRef<H> },
     Call { fun: ExprRef<H>, args: Vec<ExprRef<H>> },
     Deref { arg: ExprRef<H> }, // NOT overloaded!
     Binary { op: BinOp, lhs: ExprRef<H>, rhs: ExprRef<H> }, // NOT overloaded!

diff --git a/src/librustc_mir/tcx/expr.rs b/src/librustc_mir/tcx/expr.rs
@@ -140,11 +140,6 @@ impl<'a,'tcx:'a> Mirror<Cx<'a,'tcx>> for &'tcx hir::Expr {
                 }
             }
 
-            hir::ExprUnary(hir::UnOp::UnUniq, ref arg) => {
-                assert!(!cx.tcx.is_method_call(self.id));
-                ExprKind::Box { place: None, value: arg.to_ref() }
-            }
-
             hir::ExprUnary(op, ref arg) => {
                 if cx.tcx.is_method_call(self.id) {
                     overloaded_operator(cx, self, ty::MethodCall::expr(self.id),
@@ -154,10 +149,10 @@ impl<'a,'tcx:'a> Mirror<Cx<'a,'tcx>> for &'tcx hir::Expr {
                     let op = match op {
                         hir::UnOp::UnNot => UnOp::Not,
                         hir::UnOp::UnNeg => UnOp::Neg,
-                        hir::UnOp::UnUniq | hir::UnOp::UnDeref => {
+                        hir::UnOp::UnDeref => {
                             cx.tcx.sess.span_bug(
                                 self.span,
-                                &format!("operator should have been handled elsewhere {:?}", op));
+                                "UnDeref should have been handled elsewhere");
                         }
                     };
                     ExprKind::Unary { op: op, arg: arg.to_ref() }
@@ -296,8 +291,8 @@ impl<'a,'tcx:'a> Mirror<Cx<'a,'tcx>> for &'tcx hir::Expr {
                                   name: Field::Indexed(ident.node) },
             hir::ExprCast(ref source, _) =>
                 ExprKind::Cast { source: source.to_ref() },
-            hir::ExprBox(ref place, ref value) =>
-                ExprKind::Box { place: place.to_ref(), value: value.to_ref() },
+            hir::ExprBox(ref value) =>
+                ExprKind::Box { value: value.to_ref() },
             hir::ExprVec(ref fields) =>
                 ExprKind::Vec { fields: fields.to_ref() },
             hir::ExprTup(ref fields) =>

diff --git a/src/librustc_trans/trans/consts.rs b/src/librustc_trans/trans/consts.rs
@@ -564,10 +564,10 @@ fn const_expr_unadjusted<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
 
             let is_float = ty.is_fp();
             unsafe { match u {
-                hir::UnUniq | hir::UnDeref => const_deref(cx, te, ty).0,
-                hir::UnNot                 => llvm::LLVMConstNot(te),
-                hir::UnNeg if is_float     => llvm::LLVMConstFNeg(te),
-                hir::UnNeg                 => llvm::LLVMConstNeg(te),
+                hir::UnDeref           => const_deref(cx, te, ty).0,
+                hir::UnNot             => llvm::LLVMConstNot(te),
+                hir::UnNeg if is_float => llvm::LLVMConstFNeg(te),
+                hir::UnNeg             => llvm::LLVMConstNeg(te),
             } }
         },
         hir::ExprField(ref base, field) => {

diff --git a/src/librustc_trans/trans/debuginfo/create_scope_map.rs b/src/librustc_trans/trans/debuginfo/create_scope_map.rs
@@ -325,9 +325,7 @@ fn walk_expr(cx: &CrateContext,
         hir::ExprTupField(ref sub_exp, _) =>
             walk_expr(cx, &**sub_exp, scope_stack, scope_map),
 
-        hir::ExprBox(ref place, ref sub_expr) => {
-            place.as_ref().map(
-                |e| walk_expr(cx, &**e, scope_stack, scope_map));
+        hir::ExprBox(ref sub_expr) => {
             walk_expr(cx, &**sub_expr, scope_stack, scope_map);
         }
 

diff --git a/src/librustc_trans/trans/expr.rs b/src/librustc_trans/trans/expr.rs
@@ -673,7 +673,7 @@ fn trans_datum_unadjusted<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
         hir::ExprIndex(ref base, ref idx) => {
             trans_index(bcx, expr, &**base, &**idx, MethodCall::expr(expr.id))
         }
-        hir::ExprBox(_, ref contents) => {
+        hir::ExprBox(ref contents) => {
             // Special case for `Box<T>`
             let box_ty = expr_ty(bcx, expr);
             let contents_ty = expr_ty(bcx, &**contents);
@@ -1649,9 +1649,6 @@ fn trans_unary<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
             };
             immediate_rvalue_bcx(bcx, llneg, un_ty).to_expr_datumblock()
         }
-        hir::UnUniq => {
-            trans_uniq_expr(bcx, expr, un_ty, sub_expr, expr_ty(bcx, sub_expr))
-        }
         hir::UnDeref => {
             let datum = unpack_datum!(bcx, trans(bcx, sub_expr));
             deref_once(bcx, expr, datum, method_call)
@@ -2769,24 +2766,11 @@ fn expr_kind(tcx: &ty::ctxt, expr: &hir::Expr) -> ExprKind {
 
         hir::ExprLit(_) | // Note: LitStr is carved out above
         hir::ExprUnary(..) |
-        hir::ExprBox(None, _) |
+        hir::ExprBox(_) |
         hir::ExprAddrOf(..) |
         hir::ExprBinary(..) |
         hir::ExprCast(..) => {
             ExprKind::RvalueDatum
         }
-
-        hir::ExprBox(Some(ref place), _) => {
-            // Special case `Box<T>` for now:
-            let def_id = match tcx.def_map.borrow().get(&place.id) {
-                Some(def) => def.def_id(),
-                None => panic!("no def for place"),
-            };
-            if tcx.lang_items.exchange_heap() == Some(def_id) {
-                ExprKind::RvalueDatum
-            } else {
-                ExprKind::RvalueDps
-            }
-        }
     }
 }