ref: 4abb38f1778a60e8d3ae14af928b0192ff3a5ed2 dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4