ref: dcd9c222aa65d71e3f8a8a49edaa6e29ff6dcb3f dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4