diff --git a/src/libCom/test/epicsStackTraceTest.c b/src/libCom/test/epicsStackTraceTest.c
index d7166a47d..a4d66fe6d 100644
--- a/src/libCom/test/epicsStackTraceTest.c
+++ b/src/libCom/test/epicsStackTraceTest.c
@@ -19,7 +19,7 @@
 
 #include <string.h>
 
-#undef TEST_DEBUG
+#undef  TEST_DEBUG
 
 #define TST_BUFSZ 10000