This seem to break devel/libgnuregex, which copies files installed by this port into its ${WRKDIR}.
Not sure which port should be fixed (not sure the offending changes are intentional or unintentional), so reporting here. (Found on forcible full rebuilds by poudriere after OSVERSION bump of stable/15.)

Note that the last upgrade of devel/libgnuregex was Sep 7, 2022 in this commit.

https://github.com/freebsd/freebsd-ports/commit/fb16dfecae4a6efac9f3a78e0b759fb7a3c53de4

The failure is as follows.

> libgnuregex-6.0 depends on package: gnulib>0 - found

> Returning to build of libgnuregex-6.0

<phase: extract >

env: NO_DEPENDS=yes USER=root UID=0 GID=0

> License LGPL20+ accepted by the user

> Fetching all distfiles required by libgnuregex-6.0 for building

> Extracting for libgnuregex-6.0

/bin/mkdir -p /wrkdirs/usr/ports/devel/libgnuregex/work/libgnuregex-6.0
cp -f -a /usr/local/share/gnulib/lib/regex.c /usr/local/share/gnulib/lib/regex.h /usr/local/share/gnulib/lib/regex_internal.c /usr/local/share/gnulib/lib/regex_
internal.h /usr/local/share/gnulib/lib/regexec.c /usr/local/share/gnulib/lib/regcomp.c /wrkdirs/usr/ports/devel/libgnuregex/work/libgnuregex-6.0
cp -f -a /usr/ports/devel/libgnuregex/files/config.h /usr/ports/devel/libgnuregex/files/gnuregex.h /usr/ports/devel/libgnuregex/files/Makefile /wrkdirs/usr/por

ts/devel/libgnuregex/work/libgnuregex-6.0

<phase: patch-depends >

env: USE_PACKAGE_DEPENDS_ONLY=1 USER=root UID=0 GID=0

<phase: patch >

env: NO_DEPENDS=yes USER=root UID=0 GID=0

> Patching for libgnuregex-6.0

> Applying FreeBSD patches for libgnuregex-6.0 from /usr/ports/devel/libgnuregex/files

1 out of 2 hunks failed--saving rejects to regex.c.rej

> FAILED Applying FreeBSD patch-regex.c

> FAILED to apply cleanly FreeBSD patch(es) patch-regex.c

• Error code 1

Stop.
make: stopped making "patch" in /usr/ports/devel/libgnuregex

>> Cleaning up wrkdir

> Cleaning for libgnuregex-6.0

In D55142#1283669, @junchoon_dec.sakura.ne.jp wrote:

This seem to break devel/libgnuregex, which copies files installed by this port into its ${WRKDIR}.
Not sure which port should be fixed (not sure the offending changes are intentional or unintentional), so reporting here. (Found on forcible full rebuilds by poudriere after OSVERSION bump of stable/15.)

While a heads up might have been nice, the libgnuregex build is absolutely cursed and I don't blame him one bit for not noticing what I did over there. The libgnuregex build is definitely what needs to be fixed here, I'll see about writing a 'better' build system for it real quick.