ref: 68d9155e1fff6c4c2d69c96f3fd4e7dc66cdeebd dir: /sys/src/libc/68020/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4