diff --git a/src/tioga.h b/src/tioga.h
index 495e860..31bcb1a 100644
--- a/src/tioga.h
+++ b/src/tioga.h
@@ -34,11 +34,11 @@
  *  meshes containing element and node IDs greater than what a 4-byte signed int
  *  can support
  */
-enum : uint8_t { TIOGA_HAS_UINT64T = 1 };
+#define TIOGA_HAS_UINT64T 1
 /** Define a macro entry flagging whether TIOGA has hetereogenous execution
  *  space support, and uses the new API for registering mesh/solution data
  */
-enum : uint8_t { TIOGA_HAS_NGP_IFACE = 1 };
+#define TIOGA_HAS_NGP_IFACE 1
 
 /**
  * Topology Independent Overset Grid Assembler (TIOGA)