"Narrow scope forgives many sins." -- M. Schwern

Author: lkuper

src/comp/middle/trans.rs

@@ -7129,7 +7129,6 @@ fn trans_anon_obj(@block_ctxt bcx, &span sp, &ast::anon_obj anon_obj,
         methods = anon_obj.methods,
         dtor = none[@ast::method]);
 
-    let option::t[result] with_obj_val = none;
     let ty::t with_obj_ty;
     auto vtbl;
     alt (anon_obj.with_obj) {
@@ -7152,11 +7151,6 @@ fn trans_anon_obj(@block_ctxt bcx, &span sp, &ast::anon_obj anon_obj,
                                additional_field_tys);
         }
         case (some(?e)) {
-            // If with_obj (the object being extended) exists, translate it.
-            // Translating with_obj returns a ValueRef (pointer to a 2-word
-            // value) wrapped in a result.
-            with_obj_val = some(trans_expr(bcx, e));
-
             // TODO: What makes more sense to get the type of an expr --
             // calling ty::expr_ty(ccx.tcx, e) on it or calling
             // ty::node_id_to_type(ccx.tcx, id) on its id?
@@ -7327,17 +7321,22 @@ fn trans_anon_obj(@block_ctxt bcx, &span sp, &ast::anon_obj anon_obj,
             i += 1;
         }
 
-        // Copy a pointer to the with_obj into the object's body.
-        auto body_with_obj =
-            GEP_tup_like(bcx, body_ty, body.val,
-                         ~[0, abi::obj_body_elt_with_obj]);
-        bcx = body_with_obj.bcx;
-        alt (with_obj_val) {
-            case (some(?v)) {
+        // If there's a with_obj, copy a pointer to it into the object's body.
+        alt (anon_obj.with_obj) {
+            case (none) { }
+            case (some(?e)) {
+                // If with_obj (the object being extended) exists, translate
+                // it.  Translating with_obj returns a ValueRef (pointer to a
+                // 2-word value) wrapped in a result.
+                let result with_obj_val = trans_expr(bcx, e);
+
+                auto body_with_obj =
+                    GEP_tup_like(bcx, body_ty, body.val,
+                                 ~[0, abi::obj_body_elt_with_obj]);
+                bcx = body_with_obj.bcx;
                 bcx = copy_val(bcx, INIT, body_with_obj.val,
-                               v.val, with_obj_ty).bcx;
+                               with_obj_val.val, with_obj_ty).bcx;
             }
-            case (_) {}
         }
 
         // Store box ptr in outer pair.