Fix the named tuple constructor code to return a value

This is essentially the same change as in `intrinsics`. Returns a value
or `()` depending on whether or not the type is immediate.

Author: Aatch

src/librustc_trans/trans/base.rs

@@ -1672,8 +1672,7 @@ pub fn trans_named_tuple_constructor<'blk, 'tcx>(mut bcx: Block<'blk, 'tcx>,
                                                  disr: ty::Disr,
                                                  args: callee::CallArgs,
                                                  dest: expr::Dest,
-                                                 debug_loc: DebugLoc)
-                                                 -> Result<'blk, 'tcx> {
+                                                 debug_loc: DebugLoc) -> Result<'blk, 'tcx> {
 
     let ccx = bcx.fcx.ccx;
     let tcx = ccx.tcx();
@@ -1717,6 +1716,12 @@ pub fn trans_named_tuple_constructor<'blk, 'tcx>(mut bcx: Block<'blk, 'tcx>,
         }
     }
 
+    let val = if type_is_immediate(ccx, result_ty) && !type_is_zero_size(ccx, result_ty) {
+        load_ty(bcx, llresult, result_ty)
+    } else {
+        common::C_nil(ccx)
+    };
+
     // If the caller doesn't care about the result
     // drop the temporary we made
     let bcx = match dest {
@@ -1730,7 +1735,7 @@ pub fn trans_named_tuple_constructor<'blk, 'tcx>(mut bcx: Block<'blk, 'tcx>,
         }
     };
 
-    Result::new(bcx, llresult)
+    Result::new(bcx, val)
 }
 
 pub fn trans_tuple_struct<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,

src/librustc_trans/trans/expr.rs

@@ -585,7 +585,7 @@ fn trans_unadjusted<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
             if let ast::ExprPath(..) = f.node {
                 let fn_ty = expr_ty_adjusted(bcx, f);
                 let (fty, ret_ty) = match fn_ty.sty {
-                    ty::ty_bare_fn(_, ref fty) => {
+                    ty::TyBareFn(_, ref fty) => {
                         (fty, ty::erase_late_bound_regions(bcx.tcx(), &fty.sig.output()))
                     }
                     _ => panic!("Not calling a function?!")
@@ -595,12 +595,9 @@ fn trans_unadjusted<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
                     let is_rust_fn = fty.abi == synabi::Rust ||
                         fty.abi == synabi::RustIntrinsic;
 
-                    let valid_type =
-                        ty::type_is_scalar(ret_ty) ||
-                        ty::type_is_simd(bcx.tcx(), ret_ty);
-
-                    if is_rust_fn && type_is_immediate(bcx.ccx(), ret_ty) && valid_type {
+                    let needs_drop = type_needs_drop(bcx.tcx(), ret_ty);
 
+                    if is_rust_fn && type_is_immediate(bcx.ccx(), ret_ty) && !needs_drop {
                         let args = callee::ArgExprs(&args[..]);
                         let result = callee::trans_call_inner(bcx,
                                                               expr.debug_loc(),