Note that you also have to trust the /tools/ that generate the circuits. Nobody's doing to check every single gate on the chip against the source code; it would

Note that you also have to trust the /tools/ that generate the circuits. Nobody's doing to check every single gate on the chip against the source code; it would be easy for a VHDL compiler to lay down extra stuff. Shades of "Reflections on Trusting Trust," but in hardware. Doesn't have a complete replication loop, though, which would have the compromised hardware re-infecting the very VHDL compilers that generated the chip backdoor :-)