diff --git a/gtsam/config.h.in b/gtsam/config.h.in
index db6dd2b34..5d63624e7 100644
--- a/gtsam/config.h.in
+++ b/gtsam/config.h.in
@@ -44,7 +44,7 @@
 
 // Whether to enable timing in hybrid factor graph machinery
 // #cmakedefine01 GTSAM_HYBRID_TIMING
-#define GTSAM_HYBRID_TIMING
+#define GTSAM_HYBRID_TIMING 1
 
 // Whether we are using TBB (if TBB was found and GTSAM_WITH_TBB is enabled in CMake)
 #cmakedefine GTSAM_USE_TBB