ref: e2c5e0e2fa2df74fd2b7bf31dc3f30666d23e54a dir: /sys/src/libc/alpha/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4