Frankenchroot builds ARM on x86 without cross compiling.
Frankenchroot was created by Daniel Robbins and is a QEMU based chroot. It can be used to access live ARM systems to compile and install software using the power and resources of an X86_64 workstation. The release announcement is here:
https://forums.funtoo.org/topic/1970-announcing-fchroot-qemu-based-chroot-tool/