patch 9.0.0220: invalid memory access with for loop over NULL string Commit: https://github.com/vim/vim/commit/f6d39c31d2177549a986d170e192d8351bd571e2 Author: Bram Moolenaar <Bram@vim.org> Date: Tue Aug 16 17:50:38 2022 +0100 patch 9.0.0220: invalid memory access with for loop over NULL string Problem: Invalid memory access with for loop over NULL string. Solution: Make sure mb_ptr2len() consistently returns zero for NUL.

$! test77a - help file creating checksum on VMS
$! Created by Zoltan Arpadffy
$
$ IF P1 .NES. ""
$ THEN
$    checksum 'P1'
$    show symb CHECKSUM$CHECKSUM
$ ENDIF