ref: a873aaf1f1f75fc9f9ed1975e0b7f6e1565c4efc dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4