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

Calculating dependencies ... done!
Dependency resolution took 0.97 s (backtrack: 0/20).


The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by dev-debug/gef-2023.08::gentoo
# required by =dev-debug/gef-2023.08 (argument)
>=dev-debug/gdb-18.1 python_single_target_python3_12

!!! The ebuild selected to satisfy "dev-debug/gdb[python,python_single_target_python3_12(-)?]" has unmet requirements.
- dev-debug/gdb-18.1::gentoo USE="cet debuginfod nls python server xml -guile -lzma -multitarget -rocm -sim -source-highlight -test -vanilla -xxhash -zstd" GUILE_SINGLE_TARGET="3-0 -2-2" PYTHON_SINGLE_TARGET="python3_14 -python3_12 -python3_13"

  The following REQUIRED_USE flag constraints are unsatisfied:
    python? ( exactly-one-of ( python_single_target_python3_12 python_single_target_python3_13 python_single_target_python3_14 ) )

  The above constraints are a subset of the following complete expression:
    guile? ( exactly-one-of ( guile_single_target_2-2 guile_single_target_3-0 ) ) python? ( exactly-one-of ( python_single_target_python3_12 python_single_target_python3_13 python_single_target_python3_14 ) ) rocm? ( multitarget )

(dependency required by "dev-debug/gef-2023.08::gentoo" [ebuild])
(dependency required by "=dev-debug/gef-2023.08" [argument])