ref: 0bdfa3699dede75e657a24bd22e0e4aa7eafd5e4 dir: /sys/src/libc/386/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4