ref: 7d3cc1c55a435bd9e3d37d9bf8a9299ea9e1f87e dir: /sys/src/libc/sparc/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4