ref: 411fc48b8ca8ebd2ea32d3a26b1be309c6b8ade3 dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4