ref: 03e6d3a0f06b1f1dc2b70bf7d236e8c96bbfa120 dir: /sys/src/libc/sparc/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4