ref: 4cd03abefe80c9d7ce97d7dfb488e7ed5a8163c8 dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4