diff --git a/libsrc/core/python_ngcore.hpp b/libsrc/core/python_ngcore.hpp

index 634094ad..06d460e5 100644

--- a/libsrc/core/python_ngcore.hpp

+++ b/libsrc/core/python_ngcore.hpp

@@ -107,10 +107,12 @@ namespace ngcore

     static std::string GetName() { return "D"; }

   };

+#if __WORDSIZE > 32

   template<>

   struct PyNameTraits<size_t> {

     static std::string GetName() { return "S"; }

   };

+#endif

   template<typename T>

   struct PyNameTraits<std::shared_ptr<T>> {

diff --git a/libsrc/core/table.hpp b/libsrc/core/table.hpp

index 34f40c93..541da3eb 100644

--- a/libsrc/core/table.hpp

+++ b/libsrc/core/table.hpp

@@ -101,8 +101,10 @@ namespace ngcore

   { return TablePrefixSum32 (FlatArray<unsigned> (entrysize.Size(), (unsigned int*)(int*)(entrysize.Addr(0)))); }

   NETGEN_INLINE size_t * TablePrefixSum (FlatArray<std::atomic<int>> entrysize)

   { return TablePrefixSum32 (FlatArray<unsigned> (entrysize.Size(), (unsigned int*)(std::atomic<int>*)entrysize.Addr(0))); }

+#if __WORDSIZE > 32

   NETGEN_INLINE size_t * TablePrefixSum (FlatArray<size_t> entrysize)

   { return TablePrefixSum64 (entrysize); }

+#endif

   /**