diff --git a/src/lib/netlist/plib/ppmf.h b/src/lib/netlist/plib/ppmf.h
index b188ca0c..e037fc28 100644
--- a/src/lib/netlist/plib/ppmf.h
+++ b/src/lib/netlist/plib/ppmf.h
@@ -82,6 +82,7 @@ namespace plib {
 
 #include <algorithm>
 #include <cstdint> // uintptr_t
+#include <cstddef>
 #include <type_traits>
 #include <utility>