diff --git a/src/xdiff/xinclude.h b/src/xdiff/xinclude.h
index 752c9f3..ad27d35 100644
--- a/src/xdiff/xinclude.h
+++ b/src/xdiff/xinclude.h
@@ -20,7 +20,7 @@
  *
  */
 
-/* defines HAVE_ATTRIBUTE_UNUSED */
+// defines HAVE_ATTRIBUTE_UNUSED
 #ifdef HAVE_CONFIG_H
 # ifdef VMS
 #  include "[.auto]config.h"
@@ -29,8 +29,8 @@
 # endif
 #endif
 
-/* Mark unused function arguments with UNUSED, so that gcc -Wunused-parameter
- * can be used to check for mistakes. */
+// Mark unused function arguments with UNUSED, so that gcc -Wunused-parameter
+// can be used to check for mistakes.
 #ifdef HAVE_ATTRIBUTE_UNUSED
 # define UNUSED __attribute__((unused))
 #else
@@ -62,4 +62,4 @@
 #include "xemit.h"
 
 
-#endif /* #if !defined(XINCLUDE_H) */
+#endif // #if !defined(XINCLUDE_H)