patch 8.1.1608: the evalfunc.c file is too big
Problem: The evalfunc.c file is too big.
Solution: Move sign functionality to sign.c.
diff --git a/src/proto/evalfunc.pro b/src/proto/evalfunc.pro
index 533b982..64a246d 100644
--- a/src/proto/evalfunc.pro
+++ b/src/proto/evalfunc.pro
@@ -3,6 +3,7 @@
char_u *get_expr_name(expand_T *xp, int idx);
int find_internal_func(char_u *name);
int call_internal_func(char_u *name, int argcount, typval_T *argvars, typval_T *rettv);
+linenr_T tv_get_lnum(typval_T *argvars);
buf_T *buflist_find_by_name(char_u *name, int curtab_only);
buf_T *tv_get_buf(typval_T *tv, int curtab_only);
buf_T *get_buf_arg(typval_T *arg);