diff --git a/src/buffer.c b/src/buffer.c
index 4fc5032..9eb6716 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -2001,6 +2001,7 @@
 #ifdef FEAT_LISP
     clear_string_option(&buf->b_p_lw);
 #endif
+    clear_string_option(&buf->b_p_bkc);
 }
 
 /*