ref: 19d7ba2c8d9e53dafef81a4ea21bf3064e9a3ed2 dir: /sys/src/libc/alpha/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4