ref: 78b9c2b9f2dcc79a3d5dbfadfdea8c3e8cb1fa22 dir: /sys/src/libc/alpha/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4