ref: a9d4e5967cb7ddd34d2e6f0826ca6a38deb3b35f dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4