[inferbo] Use return_param only when callee added it

Reviewed By: mbouaziz

Differential Revision: D14661265

fbshipit-source-id: c2436f863

infer/src/bufferoverrun/bufferOverrunAnalysis.ml

@@ -95,11 +95,11 @@ module TransferFunctions = struct
     in
     let ret_var = Loc.of_var (Var.of_id ret_id) in
     let ret_val =
-      let val_of_return_var =
-        Dom.Mem.find_opt (Loc.of_pvar (Pvar.get_ret_pvar callee_pname)) callee_exit_mem
-      in
-      IOption.value_default_f val_of_return_var ~f:(fun () ->
-          Dom.Val.of_loc (Loc.of_pvar (Pvar.get_ret_param_pvar callee_pname)) )
+      match Procdesc.load callee_pname with
+      | Some callee_pdesc when Procdesc.has_added_return_param callee_pdesc ->
+          Dom.Val.of_loc (Loc.of_pvar (Pvar.get_ret_param_pvar callee_pname))
+      | _ ->
+          Dom.Mem.find (Loc.of_pvar (Pvar.get_ret_pvar callee_pname)) callee_exit_mem
     in
     Dom.Mem.add_stack ret_var (Dom.Val.subst ret_val eval_sym_trace location) mem
     |> instantiate_ret_alias