ref: 82fb9f8d5093a8ff0cda06c5618d73af4803a3f0 dir: /sys/src/libc/sparc/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4