ref: 0edcb33ca1f01f8e3c18f5ad99442da8aad2091f dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4