ref: 5ebb1a29d8250027e8b7f2287f3bfa3a6f3d13ac dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4