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

Calculating dependencies ... done!
Dependency resolution took 1.27 s (backtrack: 0/20).

[ebuild  N     ] acct-group/postgres-0-r3::gentoo  0 KiB
[ebuild  N     ] app-eselect/eselect-postgresql-2.4-r1::gentoo  5 KiB
[ebuild  N     ] app-arch/lz4-1.10.0-r1:0/1.10.0-meson::gentoo  USE="-static-libs -test" 379 KiB
[ebuild  N     ] sys-process/numactl-2.0.19::gentoo  USE="-static-libs" 441 KiB
[ebuild  N     ] sys-libs/liburing-2.15:0/2::gentoo  USE="-examples -static-libs -test" 538 KiB
[ebuild  N     ] app-text/docbook-sgml-dtd-4.5-r2:4.5::gentoo  70 KiB
[ebuild  N     ] app-text/docbook-sgml-dtd-3.0-r5:3.0::gentoo  43 KiB
[ebuild  N     ] dev-libs/cyrus-sasl-2.1.28-r5:2::gentoo  USE="gdbm pam sqlite ssl -authdaemond -berkdb -kerberos -ldapdb -mysql -openldap -postgres -sample (-selinux) -srp -static-libs -urandom" 3945 KiB
[ebuild  N     ] acct-user/postgres-0-r3::gentoo  0 KiB
[ebuild  N     ] app-text/docbook-dsssl-stylesheets-1.79-r4::gentoo  272 KiB
[ebuild  N     ] dev-db/postgresql-18.6:18::gentoo  USE="icu lz4 nls numa pam python readline server ssl uring zlib zstd -debug -doc -kerberos -ldap -llvm -oauth -perl (-selinux) -static-libs (-systemd) -tcl -uuid -xml" LLVM_SLOT="22 -17 -18 -19 -20 -21 -23" PYTHON_SINGLE_TARGET="python3_14 -python3_12 -python3_13" 22102 KiB
[ebuild  N     ] dev-libs/libmemcached-awesome-1.1.4-r1::gentoo  USE="libevent sasl -test" 518 KiB
[ebuild  N     ] dev-db/pgmemcache-2.3.0-r1::gentoo  21 KiB

Total: 13 packages (13 new), Size of downloads: 28329 KiB

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by dev-db/pgmemcache-2.3.0-r1::gentoo
# required by =dev-db/pgmemcache-2.3.0-r1 (argument)
>=dev-libs/libmemcached-awesome-1.1.4-r1 sasl