diff --git a/src/basic/vx_config/number_stack.cc b/src/basic/vx_config/number_stack.cc
index 2e8cf1ae94..c49ea25a03 100644
--- a/src/basic/vx_config/number_stack.cc
+++ b/src/basic/vx_config/number_stack.cc
@@ -33,7 +33,7 @@ using namespace std;
 ////////////////////////////////////////////////////////////////////////
 
 
-static int default_ns_alloc_inc = 100;   //  default value
+constexpr int default_ns_alloc_inc = 100;   //  default value