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.

/* crypt_zip.c */
int crypt_zip_init(cryptstate_T *state, char_u *key, char_u *salt, int salt_len, char_u *seed, int seed_len);
void crypt_zip_encode(cryptstate_T *state, char_u *from, size_t len, char_u *to);
void crypt_zip_decode(cryptstate_T *state, char_u *from, size_t len, char_u *to);
/* vim: set ft=c : */