diff --git a/src/lib/netlist/plib/ppmf.h b/src/lib/netlist/plib/ppmf.h
index 6dd80758ad5..13d627dd2a1 100644
--- a/src/lib/netlist/plib/ppmf.h
+++ b/src/lib/netlist/plib/ppmf.h
@@ -265,6 +265,9 @@ namespace plib {
 		template <class C>
 		using specific_member_function = R (C::*)(Targs...);
 
+		template <class C>
+		using const_specific_member_function = R (C::*)(Targs...) const;
+
 		class generic_class;
 		using generic_member_function = specific_member_function<generic_class>;
 
@@ -293,6 +296,9 @@ namespace plib {
 		template <class C>
 		using specific_member_function = R (C::*)(Targs...);
 
+		template <class C>
+		using const_specific_member_function = R (C::*)(Targs...) const;
+
 		class generic_class;
 		using generic_member_function = specific_member_function<generic_class>;