#1077797 grep recognizes neither [:ascii:] nor [:nonascii:]

Package:
grep
Source:
grep
Description:
GNU grep, egrep and fgrep
Submitter:
Al Ma
Date:
2024-08-02 13:09:03 UTC
Severity:
normal
#1077797#5
Date:
2024-08-02 13:08:15 UTC
From:
To:
Package: grep
Version: 3.8-5
In Debian 12 stable, open an xterm in gnome on xorg and run:
$ grep "[[:ascii:]]" /etc/services
grep: Ungültiger Name für eine Zeichenklasse
$ LC_ALL=en_US.utf8 grep "[[:ascii:]]" /etc/services
grep: Invalid character class name
The same error comes up with [:nonascii:]. However, both are listed in https://www.gnu.org/software/emacs/manual/html_node/elisp/Char-Classes.html https://www.gnu.org/software/emacs/manual/html_node/elisp/Char-Classes.html.