oech3 [1] filed a deletion request for x86_64-elf-gcc [2]: Use case of this cross-compile target is covered by gcc on Arch Linux. Arch is x86_64 only and this has arch=(x86_64) only.
[1] https://aur.archlinux.org/account/oech3/ [2] https://aur.archlinux.org/pkgbase/x86_64-elf-gcc/
