diff --git a/src/MeshTools/Test/InterleaveTest.cpp b/src/MeshTools/Test/InterleaveTest.cpp
index 74533d93c..ca2fde98c 100644
--- a/src/MeshTools/Test/InterleaveTest.cpp
+++ b/src/MeshTools/Test/InterleaveTest.cpp
@@ -15,7 +15,9 @@
 
 #include "InterleaveTest.h"
 
+#ifndef NDEBUG
 #define NDEBUG
+#endif
 
 #include <sstream>
 #include <QtTest/QTest>