Make it possible to use * to dereference a resource

Author: marijnh

src/comp/middle/alias.rs

@@ -544,10 +544,14 @@ fn expr_root(&ctx cx, @ast::expr ex, bool autoderef) ->
                     auto base_t = ty::expr_ty(*cx.tcx, base);
                     alt (ty::struct(*cx.tcx, base_t)) {
                         case (ty::ty_box(?mt)) {
-                            vec::push(ds,
-                                      rec(mut=mt.mut != ast::imm,
-                                          kind=unbox,
-                                          outer_t=base_t));
+                            vec::push(ds, rec(mut=mt.mut != ast::imm,
+                                              kind=unbox,
+                                              outer_t=base_t));
+                        }
+                        case (ty::ty_res(_, ?inner)) {
+                            vec::push(ds, rec(mut=false,
+                                              kind=unbox,
+                                              outer_t=base_t));
                         }
                     }
                     ex = base;

src/comp/middle/trans.rs

@@ -4511,8 +4511,7 @@ fn trans_for_each(&@block_ctxt cx, &@ast::local local, &@ast::expr seq,
             cx.build.Store(llenvblobptr, env_cell);
             // log "lliterbody: " + val_str(lcx.ccx.tn, lliterbody);
 
-            r =
-                trans_call(cx, f, some[ValueRef](cx.build.Load(pair)), args,
+            r = trans_call(cx, f, some[ValueRef](cx.build.Load(pair)), args,
                            seq.id);
             ret rslt(r.bcx, C_nil());
         }
@@ -4993,9 +4992,12 @@ fn trans_lval(&@block_ctxt cx, &@ast::expr e) -> lval_result {
         case (ast::expr_unary(?unop, ?base)) {
             assert (unop == ast::deref);
             auto sub = trans_expr(cx, base);
-            auto val =
-                sub.bcx.build.GEP(sub.val,
-                                  [C_int(0), C_int(abi::box_rc_field_body)]);
+            auto t = ty::expr_ty(cx.fcx.lcx.ccx.tcx, base);
+            auto offset = alt (ty::struct(cx.fcx.lcx.ccx.tcx, t)) {
+                case (ty::ty_box(_)) { abi::box_rc_field_body }
+                case (ty::ty_res(_, _)) { 1 }
+            };
+            auto val = sub.bcx.build.GEP(sub.val, [C_int(0), C_int(offset)]);
             ret lval_mem(sub.bcx, val);
         }
         case (ast::expr_self_method(?ident)) {

src/comp/middle/typeck.rs

@@ -1526,6 +1526,7 @@ fn check_expr(&@fn_ctxt fcx, &@ast::expr expr) {
                 case (ast::deref) {
                     alt (structure_of(fcx, expr.span, oper_t)) {
                         case (ty::ty_box(?inner)) { oper_t = inner.ty; }
+                        case (ty::ty_res(_, ?inner)) { oper_t = inner; }
                         case (_) {
                             auto s = "dereferencing non-box type: " +
                                 ty_to_str(fcx.ccx.tcx, oper_t);