diff --git a/src/emacs.c b/src/emacs.c
index d363a468eea..3fbf20c5031 100644
--- a/src/emacs.c
+++ b/src/emacs.c
@@ -104,6 +104,7 @@ EMACS_INT gdb_data_seg_bits = DATA_SEG_BITS;
 EMACS_INT gdb_data_seg_bits = 0;
 #endif
 EMACS_INT PVEC_FLAG = PSEUDOVECTOR_FLAG;
+EMACS_INT gdb_array_mark_flag = ARRAY_MARK_FLAG;
 
 /* Command line args from shell, as list of strings.  */
 Lisp_Object Vcommand_line_args;