ref: 1aa8352b43390f548da154b82b0b50e295d9c03f dir: /sys/src/libc/riscv64/argv0.s/
GLOBL argv0(SB), $XLEN GLOBL _tos(SB), $XLEN GLOBL _privates(SB), $XLEN GLOBL _nprivates(SB), $XLEN