patch 8.2.2846: Vim9: "echo Func()" does not give an error for using void Commit: https://github.com/vim/vim/commit/68db996b621b98066fb7ab7028ed5c6aaa3954a8 Author: Bram Moolenaar <Bram@vim.org> Date: Sun May 9 23:19:22 2021 +0200 patch 8.2.2846: Vim9: "echo Func()" does not give an error for using void Problem: Vim9: "echo Func()" does not give an error for a function without a return value. Solution: Give an error. Be more specific about why a value is invalid.

/* bufwrite.c */
char *new_file_message(void);
int buf_write(buf_T *buf, char_u *fname, char_u *sfname, linenr_T start, linenr_T end, exarg_T *eap, int append, int forceit, int reset_changed, int filtering);
/* vim: set ft=c : */