ref: 7bf5c61ea57eebbc73ec5fb2d7ffe13c690a5e0a dir: /sys/src/libc/386/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4