Re: git: f1d98862044f - main - libc: getopt{,_long}: Const correctness for C23

On 8/3/26 07:30, Lexi Winter wrote:
> The branch main has been updated by ivy:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=f1d98862044f7748c6f930e9d4339abc166a5b16
> 
> commit f1d98862044f7748c6f930e9d4339abc166a5b16
> Author:     Lexi Winter <ivy@FreeBSD.org>
> AuthorDate: 2026-08-03 14:02:51 +0000
> Commit:     Lexi Winter <ivy@FreeBSD.org>
> CommitDate: 2026-08-03 14:02:51 +0000
> 
>     libc: getopt{,_long}: Const correctness for C23
>     
>     On some platforms, e.g. Linux Clang 22.1.8 / glibc 2.43, strchr()
>     now implements the C23 behaviour where passing a const pointer to
>     strchr() also returns a const pointer. 

A note on the terminology in this and the related commits:

"const char *NAME;" is a (non-const) pointer to a const char, not a
const pointer to a (non-const) char. In short: pointer to const is now
being put to use, not const pointer.

> This breaks getopt during
>     the bootstrap build, since it assumes the return value is always
>     a mutable pointer.
>     
>     Since the pointed-to value is never modified, fix this by making
>     the pointer const.
>     
>     MFC after:      1 week
>     Reviewed by:    emaste
>     Sponsored by:   The FreeBSD Foundation
>     Differential Revision:  https://reviews.freebsd.org/D58488
> ---
>  lib/libc/stdlib/getopt.c      | 2 +-
>  lib/libc/stdlib/getopt_long.c | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/libc/stdlib/getopt.c b/lib/libc/stdlib/getopt.c
> index 2b5e3fa69032..e1edc5a3ee83 100644
> --- a/lib/libc/stdlib/getopt.c
> +++ b/lib/libc/stdlib/getopt.c
> @@ -57,7 +57,7 @@ int
>  getopt(int nargc, char * const nargv[], const char *ostr)
>  {
>  	static char *place = EMSG;		/* option letter processing */
> -	char *oli;				/* option letter list index */
> +	const char *oli;			/* option letter list index */
>  
>  	if (optreset || *place == 0) {		/* update scanning pointer */
>  		optreset = 0;
> diff --git a/lib/libc/stdlib/getopt_long.c b/lib/libc/stdlib/getopt_long.c
> index 5cf6a55649bd..99be520fe332 100644
> --- a/lib/libc/stdlib/getopt_long.c
> +++ b/lib/libc/stdlib/getopt_long.c
> @@ -349,7 +349,7 @@ static int
>  getopt_internal(int nargc, char * const *nargv, const char *options,
>  	const struct option *long_options, int *idx, int flags)
>  {
> -	char *oli;				/* option letter list index */
> +	const char *oli;			/* option letter list index */
>  	int optchar, short_too;
>  	static int posixly_correct = -1;
>  
> 
> 


-- 
===
Mark Millard
marklmi at yahoo.com