libraw-0.20 at some version added this to its configure.ac: # check if we want zlib support AC_ARG_ENABLE([zlib], [ --enable-zlib Enable zlib support for deflate compressed DNG files], [case "${enableval}" in yes) zlib=true ;; no) zlib=false ;; *) AC_MSG_ERROR([bad value ${enableval} for --enable-zlib]) ;; esac],[zlib=true]) if test x$zlib = xtrue; then PKG_CHECK_MODULES([ZLIB],[zlib],[ CPPFLAGS="$CPPFLAGS $ZLIB_CFLAGS -DUSE_ZLIB" LIBS="$LIBS $ZLIB_LIBS" AC_SUBST([PACKAGE_REQUIRES],[zlib]) ], AC_MSG_WARN([zlib support cannot be enabled]) ) fi But the ebuild didn't grow a zlib dependency, so if somehow zlib isn't installed at the time, it'll be disabled automatically. And if it was installed at the time, portage doesn't know about it and would allow uninstalling zlib as far as it's concerned. Of course that's very very unlikely to happen, given how widespread a zlib dependency is on even a minimal system, but still.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=6a42d29813dc7ed4de374803b65bbc779746a45e commit 6a42d29813dc7ed4de374803b65bbc779746a45e Author: Sam James <sam@gentoo.org> AuthorDate: 2022-12-20 08:13:09 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2022-12-20 08:14:36 +0000 media-libs/libraw: add 0.21.0 Closes: https://bugs.gentoo.org/830441 Signed-off-by: Sam James <sam@gentoo.org> media-libs/libraw/Manifest | 1 + media-libs/libraw/libraw-0.21.0.ebuild | 60 ++++++++++++++++++++++++++++++++++ 2 files changed, 61 insertions(+)