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

Calculating dependencies ... done!
Dependency resolution took 0.82 s (backtrack: 0/20).


!!! All ebuilds that could satisfy "=sys-libs/glibc-2.40-r11" have been masked.
!!! One of the following masked packages is required to complete your request:
- sys-libs/glibc-2.40-r11::gentoo (masked by: package.mask)
/Volumes/Disk 1/Repository/portage-git/profiles/package.mask:
# Andreas K. Hüttel <dilfridge@gentoo.org> (2017-05-21)
# (and others, updated later)
# These old versions of toolchain packages (binutils, gcc, glibc) are no
# longer officially supported and are not suitable for general use. Using
# these packages can result in build failures (and possible breakage) for
# many packages, and may leave your system vulnerable to known security
# exploits.
# If you still use one of these old toolchain packages, please upgrade (and
# switch the compiler / the binutils) ASAP. If you need them for a specific
# (isolated) use case, feel free to unmask them on your system.


For more information, see the MASKED PACKAGES section in the emerge
man page or refer to the Gentoo Handbook.