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

Calculating dependencies ... done!
Dependency resolution took 1.16 s (backtrack: 0/20).

[ebuild  N     ] sys-apps/keyutils-1.6.3-r1:0/1.9::gentoo  USE="-static -static-libs -test" 134 KiB
[ebuild  N     ] dev-lang/yasm-1.3.0-r2::gentoo  USE="nls" 1458 KiB
[ebuild  N     ] dev-libs/libev-4.33::gentoo  USE="-static-libs" 557 KiB
[ebuild  N     ] dev-libs/libverto-0.3.2-r1::gentoo  USE="libev -glib -libevent" 375 KiB
[ebuild  N     ] app-crypt/mit-krb5-1.22.2-r2::gentoo  USE="keyutils nls pkinit -doc -lmdb -openldap (-selinux) -test -xinetd" CPU_FLAGS_X86="aes" 8543 KiB
[ebuild  N     ] virtual/krb5-0-r1::gentoo  0 KiB
[ebuild  N     ] dev-libs/cyrus-sasl-2.1.28-r5:2::gentoo  USE="gdbm kerberos pam sqlite ssl -authdaemond -berkdb -ldapdb -mysql -openldap -postgres -sample (-selinux) -srp -static-libs -urandom" 3945 KiB
[ebuild  N     ] app-admin/mongosh-bin-2.3.4::gentoo  80129 KiB

Total: 8 packages (8 new), Size of downloads: 95138 KiB

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by app-admin/mongosh-bin-2.3.4::gentoo
# required by =app-admin/mongosh-bin-2.3.4 (argument)
>=dev-libs/cyrus-sasl-2.1.28-r5 kerberos