Merge pull request diffblue#2107 from thk123/feature/TG-3271/interpreter-tracking-mock-exceptions

Extension to interpreter class [TG-3271]

Author: Thomas Kiley

src/goto-programs/interpreter_class.h

@@ -85,6 +85,7 @@ class interpretert:public messaget
     irep_idt calling_function;
     function_assignmentst return_assignments;
     function_assignmentst param_assignments;
+    function_assignmentst exception_assignments;
   };
 
   // list_input_varst maps function identifiers onto a vector of [name = value]