Subject: Re: [PATCH 3/6] do not discard const: adjust to non-const data types

From: Junio C Hamano <[email-masked]>
Date: Thu, 26 Mar 2026 10:28:54 -0700

Michael J Gruber <[email-masked]> writes:

> We use data types (such as string_list's util member) which are not
> necessarily "non-const in practice" (such as the list of environment
> variables in run-command.c) but are not declared "const". Rather than
> duplicating data types (e.g. with a new constr_string_list), discard the
> const explicitly for now to quell ISOC23 warnings.
> ---
>  http-push.c   | 2 +-
>  run-command.c | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/http-push.c b/http-push.c
> index 9ae6062198..acc7f1d8fa 100644
> --- a/http-push.c
> +++ b/http-push.c
> @@ -1772,7 +1772,7 @@ int cmd_main(int argc, const char **argv)
>  			str_end_url_with_slash(arg, &repo->url);
>  			repo->path_len = strlen(repo->url);
>  			if (path) {
> -				repo->path = strchr(path+2, '/');
> +				repo->path = (char *) strchr(path+2, '/');
>  				if (repo->path)
>  					repo->path_len = strlen(repo->path);
>  			}
> diff --git a/run-command.c b/run-command.c
> index 32c290ee6a..1db02ef030 100644
> --- a/run-command.c
> +++ b/run-command.c
> @@ -604,7 +604,7 @@ static void trace_add_env(struct strbuf *dst, const char *const *deltaenv)
>  	/* Last one wins, see run-command.c:prep_childenv() for context */
>  	for (e = deltaenv; e && *e; e++) {
>  		struct strbuf key = STRBUF_INIT;
> -		char *equals = strchr(*e, '=');
> +		char *equals = (char *) strchr(*e, '=');
>  
>  		if (equals) {
>  			strbuf_add(&key, *e, equals - *e);

I didn't look at the other http-push.c one, but this part with a bit
wider context reads like this:

	for (e = deltaenv; e && *e; e++) {
		struct strbuf key = STRBUF_INIT;
		char *equals = strchr(*e, '=');

		if (equals) {
			strbuf_add(&key, *e, equals - *e);
			string_list_insert(&envs, key.buf)->util = equals + 1;
		} else {
			string_list_insert(&envs, *e)->util = NULL;
		}
		strbuf_release(&key);
	}

I wonder if the cast to strip away constness wants to go near the
assignment to ->util.