Fix and cleanup callee shims

src/librustc_trans/callee.rs

@@ -502,15 +502,15 @@ fn trans_fn_pointer_shim<'a, 'tcx>(
     let fcx = FunctionContext::new(ccx, llfn, fn_ty);
     let bcx = fcx.get_entry_block();
 
-    let llargs = get_params(fcx.llfn);
+    let mut llargs = get_params(fcx.llfn);
 
-    let self_idx = fcx.fn_ty.ret.is_indirect() as usize;
+    let self_arg = llargs.remove(fcx.fn_ty.ret.is_indirect() as usize);
     let llfnpointer = llfnpointer.unwrap_or_else(|| {
         // the first argument (`self`) will be ptr to the fn pointer
         if is_by_ref {
-            bcx.load(llargs[self_idx])
+            bcx.load(self_arg)
         } else {
-            llargs[self_idx]
+            self_arg
         }
     });
 
@@ -522,16 +522,7 @@ fn trans_fn_pointer_shim<'a, 'tcx>(
     let fn_ret = callee.ty.fn_ret();
     let fn_ty = callee.direct_fn_type(ccx, &[]);
 
-    let mut args = Vec::new();
-
-    if fn_ty.ret.is_indirect() {
-        if !fn_ty.ret.is_ignore() {
-            args.push(get_param(fcx.llfn, 0));
-        }
-    }
-    args.extend_from_slice(&llargs[(self_idx + 1)..]);
-
-    let llret = bcx.call(llfnpointer, &args, None);
+    let llret = bcx.call(llfnpointer, &llargs, None);
     fn_ty.apply_attrs_callsite(llret);
 
     if fn_ret.0.is_never() {

src/librustc_trans/meth.rs

@@ -12,7 +12,7 @@ use attributes;
 use llvm::{ValueRef, get_params};
 use rustc::traits;
 use abi::FnType;
-use callee::Callee;
+use callee::{Callee, CalleeData};
 use common::*;
 use consts;
 use declare;
@@ -84,14 +84,20 @@ pub fn trans_object_shim<'a, 'tcx>(ccx: &'a CrateContext<'a, 'tcx>,
     let fcx = FunctionContext::new(ccx, llfn, fn_ty);
     let bcx = fcx.get_entry_block();
 
-    let llargs = get_params(fcx.llfn);
+    let mut llargs = get_params(fcx.llfn);
     let fn_ret = callee.ty.fn_ret();
     let fn_ty = callee.direct_fn_type(ccx, &[]);
 
-    let mut args = Vec::new();
-
-    args.extend_from_slice(&llargs);
-    let llret = bcx.call(callee.reify(ccx), &args, None);
+    let fn_ptr = match callee.data {
+        CalleeData::Virtual(idx) => {
+            let fn_ptr = get_virtual_method(&bcx,
+                llargs.remove(fn_ty.ret.is_indirect() as usize + 1), idx);
+            let llty = fn_ty.llvm_type(bcx.ccx()).ptr_to();
+            bcx.pointercast(fn_ptr, llty)
+        },
+        _ => bug!("trans_object_shim called with non-virtual callee"),
+    };
+    let llret = bcx.call(fn_ptr, &llargs, None);
     fn_ty.apply_attrs_callsite(llret);
 
     if fn_ret.0.is_never() {

src/test/run-pass/trans-object-shim.rs

@@ -0,0 +1,14 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+fn main() {
+    assert_eq!((ToString::to_string as fn(&(ToString+'static)) -> String)(&"foo"),
+        String::from("foo"));
+}