ref: eeb96dca21dfc28afa69f3d00fa6f2cdb7e9b1b8 dir: /sys/src/libc/alpha/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4