diff --git a/os/busfault.h b/os/busfault.h
index d31d046fc..0cc5a6d80 100644
--- a/os/busfault.h
+++ b/os/busfault.h
@@ -27,6 +27,8 @@
 
 #include <X11/Xdefs.h>
 
+#include "misc.h"                         /* for TRUE/FALSE */
+
 #ifdef HAVE_SIGACTION
 
 #include <sys/types.h>