Re: emacs-31 a9fc13614ec: Export GIT_OPTIONAL_LOCKS=0 for "git status" invocations (bug#80903)

> From: [email protected]
> Date: Fri, 31 Jul 2026 12:00:15 -0400
> 
> branch: emacs-31
> commit a9fc13614eca8aaa34d227b28c4c4d37b13212af
> Author: Sean Whitton <[email protected]>
> Commit: Sean Whitton <[email protected]>
> 
>     Export GIT_OPTIONAL_LOCKS=0 for "git status" invocations (bug#80903)
>     
>     * lisp/vc/vc-git.el (vc-git--env-vars): New function.
>     (vc-git-command, vc-git--call): Use it (bug#80903).
> ---
>  lisp/vc/vc-git.el | 39 +++++++++++++++++++--------------------
>  1 file changed, 19 insertions(+), 20 deletions(-)
> 
> diff --git a/lisp/vc/vc-git.el b/lisp/vc/vc-git.el
> index f336aae984d..17c358e25d5 100644
> --- a/lisp/vc/vc-git.el
> +++ b/lisp/vc/vc-git.el
> @@ -2884,6 +2884,21 @@ page for the meanings of these attributes."
>  
>  ;;; Internal commands
>  
> +(defun vc-git--env-vars (subcommand)
> +  "Return env vars for the `process-environment' of Git processes."
> +  `("GIT_DIR"
> +    ,@(and vc-git-use-literal-pathspecs
> +           '("GIT_LITERAL_PATHSPECS=1"))
> +    ;; Avoid optional repository locking during background operations
> +    ;; (bug#21559, bug#80903).  Skipping these locks is always safe and
> +    ;; can only lead to subsequent commands running more slowly.
> +    ;; The "git status" case covers how `vc-checkin' uses
> +    ;; `vc-dir-resynch-file' to update the display state of files
> +    ;; undergoing an asynchronous check-in.
> +    ,@(and (or revert-buffer-in-progress
> +               (equal subcommand "status"))
> +           '("GIT_OPTIONAL_LOCKS=0"))))

GIT_OPTIONAL_LOCKS is supported only since Git 2.15.  Would it be
possible to use the --no-optional-locks command-line option instead?