diff --git a/src/proto/ex_cmds.pro b/src/proto/ex_cmds.pro
index 1a15c88..b2c77cd 100644
--- a/src/proto/ex_cmds.pro
+++ b/src/proto/ex_cmds.pro
@@ -40,6 +40,7 @@
 int read_viminfo_sub_string __ARGS((vir_T *virp, int force));
 void write_viminfo_sub_string __ARGS((FILE *fp));
 void free_old_sub __ARGS((void));
+void free_signs __ARGS((void));
 int prepare_tagpreview __ARGS((int undo_sync));
 void ex_help __ARGS((exarg_T *eap));
 char_u *check_help_lang __ARGS((char_u *arg));