ref: 69c3c0e6f0b5ce8ea4efc65a3898c56f4d6bc513 dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4