ref: 4ec88571a4d7a4d77043c6d0b9268ea52d8ae788 dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4