ref: b68b2cd425a4ab62b6fb62d5906d2f1de5a8f1a6 dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4