❯ zig build-obj -target arm-freestanding-eabi -mcpu=arm1176jzf_s+v6kz+v5t -fPIC boot.S -femit-bin=boot.o
error(compilation): clang failed with stderr: boot.S:29:5: error: instruction requires: armv5t
    blx r3
    ^
boot.S:32:5: error: instruction requires: armv6k
    wfe
    ^

boot.S:1:1: error: unable to build C object: clang exited with code 1