ref: 80e9f40ca5ea8652e5f4ccdaec72e26fedb526b4 dir: /sys/src/libc/alpha/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4