These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.18 s (backtrack: 0/20).

[ebuild  N     ] media-libs/alsa-topology-conf-1.2.5.1-r1::gentoo  USE="-verify-sig" 12 KiB
[ebuild  N     ] media-libs/alsa-ucm-conf-1.2.16.1::gentoo  USE="-verify-sig" 83 KiB
[ebuild  N     ] media-libs/alsa-lib-1.2.16.1::gentoo  USE="python -debug -doc -verify-sig" PYTHON_SINGLE_TARGET="python3_14 -python3_12 -python3_13 (-python3_15)" 1104 KiB
[ebuild  N     ] net-libs/liblockfile-1.17::gentoo  USE="-static-libs" 69 KiB
[ebuild  N     ] app-eselect/eselect-ctags-1.20::gentoo  9 KiB
[ebuild  N     ] app-eselect/eselect-emacs-1.20::gentoo  0 KiB
[ebuild  N     ] app-emacs/emacs-common-1.14::gentoo  USE="-games -gsettings -gui" 66 KiB
[ebuild  N     ] app-editors/emacs-31.1-r2:31::gentoo  USE="X acl alsa cairo dbus gif gmp gpm harfbuzz inotify jpeg libxml2 png sqlite ssl threads tiff xattr xpm zlib -Xaw3d (-aqua) -athena -dynamic-loading -games -gfile -gsettings -gtk -gui -gzip-el -imagemagick -jit -lcms -livecd -m17n-lib -mailutils -motif (-selinux) -sound -source -svg (-systemd) -toolkit-scroll-bars -tree-sitter -valgrind -webp -wide-int -xft -xwidgets" 56622 KiB
[ebuild  N     ] app-emacs/parsebib-6.7::gentoo  USE="-test" 30 KiB
[ebuild  N     ] app-emacs/dash-2.20.0::gentoo  167 KiB
[ebuild  N     ] app-emacs/s-1.13.1::gentoo  62 KiB
[ebuild  N     ] app-emacs/compat-31.1.0.0::gentoo  140 KiB
[ebuild  N     ] app-emacs/queue-0.2::gentoo  3 KiB
[ebuild  N     ] app-emacs/string-inflection-1.0.16::gentoo  7 KiB
[ebuild  N     ] app-emacs/f-0.21.0-r1::gentoo  USE="-test" 42 KiB
[ebuild  N     ] app-emacs/citeproc-el-0.9.4-r1::gentoo  USE="-test" 108 KiB
[ebuild  N     ] app-emacs/citar-1.4.0::gentoo  1568 KiB

Total: 17 packages (17 new), Size of downloads: 60083 KiB

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by app-emacs/citeproc-el-0.9.4-r1::gentoo
# required by app-emacs/citar-1.4.0::gentoo
# required by =app-emacs/citar-1.4.0 (argument)
>=app-editors/emacs-31.1-r2 libxml2

 * In order to avoid wasting time, backtracking has terminated early
 * due to the above autounmask change(s). The --autounmask-backtrack=y
 * option can be used to force further backtracking, but there is no
 * guarantee that it will produce a solution.