ref: 5ee0dc9fb56e6d0807ff5f00c70e766efe06bc1e dir: /sys/src/libc/sparc/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4