-#ifdef __HPUX__
- // under HP-UX XKBlib.h defines structures with field named "explicit" -
- // which is, of course, an error for a C++ compiler
+#ifdef HAVE_X11_XKBLIB_H
+ #ifdef __HPUX__
+ /* under HP-UX XKBlib.h defines structures with field named "explicit" -
+ * which is, of course, an error for a C++ compiler */