ref: 5aa2a1a845dd073fdf6c2772f1d0e3e8bc04493c dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4