NetBSD uses this patch in its present-day releases,
https://github.com/NetBSD/pkgsrc/commit/72ca05d074a5d4a271f71fd92a6370965674007d

and it is necessary for Android 14+ because part of Android 14's source code
is copied and pasted from NetBSD.
https://android-review.googlesource.com/c/platform/bionic/+/2290937

$NetBSD: patch-modules_filter_modes_perl.amf,v 1.1 2021/05/11 01:26:25 rin Exp $

Fix for regex(3) update for NetBSD 9.99;
Stop using GNU regex(3) extension \w.

--- a/modules/filter/modes/perl.amf.orig	2021-05-11 10:16:54.496163627 +0900
+++ b/modules/filter/modes/perl.amf	2021-05-11 10:17:11.072694968 +0900
@@ -2,7 +2,7 @@
 
 ASPELL >=0.60.1
 
-MAGIC /0:256:^[ \t]*\#!((\/\w*)+)\/perl/pl/pm
+MAGIC /0:256:^[ \t]*\#!((\/[[:alnum:]_]*)+)\/perl/pl/pm
 MAGIC /<noregex>/pl/pm
 
 DESCRIPTION mode for checking Perl comments and string literals