ref: 0ab5d34be4b8b9faa96d4691de95d6ae8c691f0b dir: /sys/src/libc/68000/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4