During our on going adventures of getting ffs fully building from stage1 up through stage2 and stage3 we discovered that the upstream app-admin/eselect incorrectly sets its Bash shebang to /usr/bin/bash when installed in a ffs stage1. This path does not exist. Only /bin/bash does.

This causes some major breakage further down the process during a metro stage3 build in two distinct places, but theoretically any where eselect would be invoked:

1. tmp/steps/chroot/run.metro: line 154: /usr/bin/eselect: cannot execute: required file not found

    

1. Line 30 of the current app-select/eselect-rust ebuild : 

   eselect rust update --if-unset

This was discovered through multiple ffs stage3 metro builds over the past couple days. And finally verified fully by fchrooting directly into a metro built arm64-bit raspi4 stage2:

>>> Entering arm-64bit (cortex-a72 CPU) fchroot...
/bin/cp /etc/resolv.conf /var/tmp/metro/work/next/stage3-raspi4-next-2022-10-eselect python list | sed -n -e '1d' -e 's/^.* \(python[3]\..\).*$/\1/g' -e '/python3/p'
bash: /usr/bin/eselect: cannot execute: required file not found
fchroot # eselect version
bash: /usr/bin/eselect: cannot execute: required file not found
fchroot # head`head': head -n1 /usr/bin/eselect
#!/usr/bin/bash
fchroot # stat /usr/bin/bash
/usr/bin/stat: cannot statx '/usr/bin/bash': No such file or directory