diff --git a/src/regexp.c b/src/regexp.c
index 0a6695c..ceeb899 100644
--- a/src/regexp.c
+++ b/src/regexp.c
@@ -38,11 +38,11 @@
  * Named character class support added by Walter Briscoe (1998 Jul 01)
  */
 
-/* Uncomment the first if you do not want to see debugging logs or files
- * related to regular expressions, even when compiling with -DDEBUG.
- * Uncomment the second to get the regexp debugging. */
-/* #undef DEBUG */
-/* #define DEBUG */
+// By default: do not create debugging logs or files related to regular
+// expressions, even when compiling with -DDEBUG.
+// Uncomment the second line to get the regexp debugging.
+#undef DEBUG
+// #define DEBUG
 
 #include "vim.h"