1 files changed, 1 insertions, 0 deletions

diff --git a/src/alloc.c b/src/alloc.c
index 62687f732d5..0030de4842c 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -2346,6 +2346,7 @@ mark_kboards ()
       mark_object (&kb->Vlast_command);
       mark_object (&kb->Vreal_last_command);
       mark_object (&kb->Vprefix_arg);
+      mark_object (&kb->Vlast_prefix_arg);
       mark_object (&kb->kbd_queue);
       mark_object (&kb->defining_kbd_macro);
       mark_object (&kb->Vlast_kbd_macro);