diff --git a/src/proto/evalfunc.pro b/src/proto/evalfunc.pro
index 78998ff..a720b64 100644
--- a/src/proto/evalfunc.pro
+++ b/src/proto/evalfunc.pro
@@ -10,9 +10,9 @@
 type_T *internal_func_ret_type(int idx, int argcount, type2_T *argtypes, type_T **decl_type, garray_T *type_gap);
 int internal_func_is_map(int idx);
 int check_internal_func(int idx, int argcount);
-int call_internal_func(char_u *name, int argcount, typval_T *argvars, typval_T *rettv);
+funcerror_T call_internal_func(char_u *name, int argcount, typval_T *argvars, typval_T *rettv);
 void call_internal_func_by_idx(int idx, typval_T *argvars, typval_T *rettv);
-int call_internal_method(char_u *name, int argcount, typval_T *argvars, typval_T *rettv, typval_T *basetv);
+funcerror_T call_internal_method(char_u *name, int argcount, typval_T *argvars, typval_T *rettv, typval_T *basetv);
 int non_zero_arg(typval_T *argvars);
 buf_T *get_buf_arg(typval_T *arg);
 win_T *get_optional_window(typval_T *argvars, int idx);
diff --git a/src/proto/userfunc.pro b/src/proto/userfunc.pro
index 94b53f6..cda0389 100644
--- a/src/proto/userfunc.pro
+++ b/src/proto/userfunc.pro
@@ -9,7 +9,7 @@
 void emsg_funcname(char *ermsg, char_u *name);
 int get_func_arguments(char_u **arg, evalarg_T *evalarg, int partial_argc, typval_T *argvars, int *argcount);
 int get_func_tv(char_u *name, int len, typval_T *rettv, char_u **arg, evalarg_T *evalarg, funcexe_T *funcexe);
-char_u *fname_trans_sid(char_u *name, char_u *fname_buf, char_u **tofree, int *error);
+char_u *fname_trans_sid(char_u *name, char_u *fname_buf, char_u **tofree, funcerror_T *error);
 void func_name_with_sid(char_u *name, int sid, char_u *buffer);
 ufunc_T *find_func_even_dead(char_u *name, int flags);
 ufunc_T *find_func(char_u *name, int is_global);
@@ -24,8 +24,8 @@
 void funcdepth_restore(int depth);
 funccall_T *create_funccal(ufunc_T *fp, typval_T *rettv);
 void remove_funccal(void);
-int check_user_func_argcount(ufunc_T *fp, int argcount);
-int call_user_func_check(ufunc_T *fp, int argcount, typval_T *argvars, typval_T *rettv, funcexe_T *funcexe, dict_T *selfdict);
+funcerror_T check_user_func_argcount(ufunc_T *fp, int argcount);
+funcerror_T call_user_func_check(ufunc_T *fp, int argcount, typval_T *argvars, typval_T *rettv, funcexe_T *funcexe, dict_T *selfdict);
 void save_funccal(funccal_entry_T *entry);
 void restore_funccal(void);
 funccall_T *get_current_funccal(void);
@@ -37,7 +37,7 @@
 int get_callback_depth(void);
 int call_callback(callback_T *callback, int len, typval_T *rettv, int argcount, typval_T *argvars);
 varnumber_T call_callback_retnr(callback_T *callback, int argcount, typval_T *argvars);
-void user_func_error(int error, char_u *name, int found_var);
+void user_func_error(funcerror_T error, char_u *name, int found_var);
 int call_func(char_u *funcname, int len, typval_T *rettv, int argcount_in, typval_T *argvars_in, funcexe_T *funcexe);
 int call_simple_func(char_u *funcname, int len, typval_T *rettv);
 char_u *printable_func_name(ufunc_T *fp);