Centralise the handling of attributes on extern functions

src/librustc_trans/trans/base.rs

@@ -677,11 +677,8 @@ pub fn trans_external_path<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
                     ccx.sess().bug("unexpected intrinsic in trans_external_path")
                 }
                 _ => {
-                    let llfn = foreign::register_foreign_item_fn(ccx, fn_ty.abi,
-                                                                 t, &name);
                     let attrs = csearch::get_item_attrs(&ccx.sess().cstore, did);
-                    attributes::from_fn_attrs(ccx, &attrs, llfn);
-                    llfn
+                    foreign::register_foreign_item_fn(ccx, fn_ty.abi, t, &name, &attrs)
                 }
             }
         }
@@ -2418,9 +2415,7 @@ pub fn get_item_val(ccx: &CrateContext, id: ast::NodeId) -> ValueRef {
                     let abi = ccx.tcx().map.get_foreign_abi(id);
                     let ty = ccx.tcx().node_id_to_type(ni.id);
                     let name = foreign::link_name(&*ni);
-                    let llfn = foreign::register_foreign_item_fn(ccx, abi, ty, &name);
-                    attributes::from_fn_attrs(ccx, &ni.attrs, llfn);
-                    llfn
+                    foreign::register_foreign_item_fn(ccx, abi, ty, &name, &ni.attrs)
                 }
                 hir::ForeignItemStatic(..) => {
                     foreign::register_static(ccx, &*ni)

src/librustc_trans/trans/foreign.rs

@@ -187,7 +187,8 @@ pub fn get_extern_fn(ccx: &CrateContext,
 /// Registers a foreign function found in a library. Just adds a LLVM global.
 pub fn register_foreign_item_fn<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
                                           abi: Abi, fty: Ty<'tcx>,
-                                          name: &str) -> ValueRef {
+                                          name: &str,
+                                          attrs: &[hir::Attribute])-> ValueRef {
     debug!("register_foreign_item_fn(abi={:?}, \
             ty={:?}, \
             name={})",
@@ -211,6 +212,7 @@ pub fn register_foreign_item_fn<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
 
     let llfn = get_extern_fn(ccx, &mut *ccx.externs().borrow_mut(), name, cc, llfn_ty, fty);
     add_argument_attributes(&tys, llfn);
+    attributes::from_fn_attrs(ccx, attrs, llfn);
     llfn
 }
 
@@ -489,8 +491,7 @@ pub fn trans_foreign_mod(ccx: &CrateContext, foreign_mod: &hir::ForeignMod) {
                                                      "foreign fn's sty isn't a bare_fn_ty?")
                     }
 
-                    let llfn = register_foreign_item_fn(ccx, abi, ty, &lname);
-                    attributes::from_fn_attrs(ccx, &foreign_item.attrs, llfn);
+                    register_foreign_item_fn(ccx, abi, ty, &lname, &foreign_item.attrs);
                     // Unlike for other items, we shouldn't call
                     // `base::update_linkage` here.  Foreign items have
                     // special linkage requirements, which are handled