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

Calculating dependencies ... done!
Dependency resolution took 1.73 s (backtrack: 0/20).

[ebuild     U  ] app-shells/bash-5.3_p20-r1::gentoo [5.3_p9::gentoo] USE="net nls pgo plugins* (readline) -afs -bashlogger -examples -mem-scramble -verify-sig" 11137 KiB
[ebuild  N     ] acct-group/munge-0-r2::gentoo  0 KiB
[ebuild  N     ] acct-user/munge-0-r2::gentoo  0 KiB
[ebuild  N     ] x11-libs/libpciaccess-0.19::gentoo  USE="zlib -static-libs" 64 KiB
[ebuild  N     ] sys-auth/munge-0.5.18::gentoo  USE="-debug -gcrypt -static-libs" 456 KiB
[ebuild  N     ] sys-apps/hwloc-2.12.2:0/15::gentoo  USE="X cairo cpuid pci -cuda -debug -doc -l0 -nvml -rocm (-selinux) -static-libs -svg -udev -valgrind -xml" VIDEO_CARDS="-nvidia" 5504 KiB
[ebuild  N     ] sys-cluster/pmix-6.1.0::gentoo  USE="munge -debug -pmi" 10552 KiB
[ebuild  N     ] sys-cluster/prrte-4.1.0-r1:0/4::gentoo  10247 KiB
[ebuild  N     ] sys-cluster/openmpi-5.0.9-r1::gentoo  USE="-cma -cuda -fortran -peruse -romio -valgrind" OPENMPI_FABRICS="-knem -ofed" OPENMPI_RM="-pbs (-slurm)" 29650 KiB
[ebuild  N     ] virtual/mpi-2.0-r8::gentoo  USE="threads -cxx -fortran -nullmpi -romio" 0 KiB
[ebuild  N     ] sys-cluster/libcircle-0.3.0::gentoo  USE="-doc -test" 377 KiB
[ebuild  N     ] app-shells/mpibash-1.5::gentoo  USE="-examples" 370 KiB

Total: 12 packages (1 upgrade, 11 new), Size of downloads: 68353 KiB

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by app-shells/mpibash-1.5::gentoo
# required by =app-shells/mpibash-1.5 (argument)
>=app-shells/bash-5.3_p20-r1 plugins