ref: 463bbddb8d6cdc1fb3df8dce42b9b5e0afd3cedb dir: /sys/src/libc/386/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4