diff --git a/src/globals.h b/src/globals.h
index 0931466..d6abc67 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -231,6 +231,7 @@
 EXTERN int	debug_break_level INIT(= -1);	/* break below this level */
 EXTERN int	debug_did_msg INIT(= FALSE);	/* did "debug mode" message */
 EXTERN int	debug_tick INIT(= 0);		/* breakpoint change count */
+EXTERN int	debug_backtrace_level INIT(= 0); /* breakpoint backtrace level */
 # ifdef FEAT_PROFILE
 EXTERN int	do_profiling INIT(= PROF_NONE);	/* PROF_ values */
 # endif