patch 7.4.1976
Problem:    Number variables are not 64 bits while they could be.
Solution:   Add the num64 feature. (Ken Takata)
diff --git a/src/proto/eval.pro b/src/proto/eval.pro
index 60fad80..4ff063e 100644
--- a/src/proto/eval.pro
+++ b/src/proto/eval.pro
@@ -19,12 +19,12 @@
 int skip_expr(char_u **pp);
 char_u *eval_to_string(char_u *arg, char_u **nextcmd, int convert);
 char_u *eval_to_string_safe(char_u *arg, char_u **nextcmd, int use_sandbox);
-int eval_to_number(char_u *expr);
+varnumber_T eval_to_number(char_u *expr);
 list_T *eval_spell_expr(char_u *badword, char_u *expr);
 int get_spellword(list_T *list, char_u **pp);
 typval_T *eval_expr(char_u *arg, char_u **nextcmd);
 int call_vim_function(char_u *func, int argc, char_u **argv, int safe, int str_arg_only, typval_T *rettv);
-long call_func_retnr(char_u *func, int argc, char_u **argv, int safe);
+varnumber_T call_func_retnr(char_u *func, int argc, char_u **argv, int safe);
 void *call_func_retstr(char_u *func, int argc, char_u **argv, int safe);
 void *call_func_retlist(char_u *func, int argc, char_u **argv, int safe);
 void *save_funccal(void);
@@ -76,11 +76,11 @@
 dictitem_T *dictitem_alloc(char_u *key);
 void dictitem_free(dictitem_T *item);
 int dict_add(dict_T *d, dictitem_T *item);
-int dict_add_nr_str(dict_T *d, char *key, long nr, char_u *str);
+int dict_add_nr_str(dict_T *d, char *key, varnumber_T nr, char_u *str);
 int dict_add_list(dict_T *d, char *key, list_T *list);
 dictitem_T *dict_find(dict_T *d, char_u *key, int len);
 char_u *get_dict_string(dict_T *d, char_u *key, int save);
-long get_dict_number(dict_T *d, char_u *key);
+varnumber_T get_dict_number(dict_T *d, char_u *key);
 int string2float(char_u *text, float_T *value);
 char_u *get_function_name(expand_T *xp, int idx);
 char_u *get_expr_name(expand_T *xp, int idx);
@@ -92,8 +92,8 @@
 float_T vim_round(float_T f);
 long do_searchpair(char_u *spat, char_u *mpat, char_u *epat, int dir, char_u *skip, int flags, pos_T *match_pos, linenr_T lnum_stop, long time_limit);
 char_u *get_callback(typval_T *arg, partial_T **pp);
-void set_vim_var_nr(int idx, long val);
-long get_vim_var_nr(int idx);
+void set_vim_var_nr(int idx, varnumber_T val);
+varnumber_T get_vim_var_nr(int idx);
 char_u *get_vim_var_str(int idx);
 list_T *get_vim_var_list(int idx);
 void set_vim_var_char(int c);
@@ -108,8 +108,8 @@
 typval_T *alloc_tv(void);
 void free_tv(typval_T *varp);
 void clear_tv(typval_T *varp);
-long get_tv_number(typval_T *varp);
-long get_tv_number_chk(typval_T *varp, int *denote);
+varnumber_T get_tv_number(typval_T *varp);
+varnumber_T get_tv_number_chk(typval_T *varp, int *denote);
 char_u *get_tv_string(typval_T *varp);
 char_u *get_tv_string_buf(typval_T *varp, char_u *buf);
 char_u *get_tv_string_chk(typval_T *varp);