diff --git a/pdns/sstuff.hh b/pdns/sstuff.hh
index c696b99afc87..e673c320dde6 100644
--- a/pdns/sstuff.hh
+++ b/pdns/sstuff.hh
@@ -416,7 +416,7 @@ public:
   }
 
 private:
-  static const size_t s_buflen{4096};
+  static constexpr size_t s_buflen{4096};
   std::string d_buffer;
   int d_socket;
 };