&gt; guaranteed to be free of such backdoors.<p>You are thinking of another kind of backdoor than the one being discussed. The backdooring technique being discussed relies on a compiler bug hidden in plain sight in the compiler&#x27;s source code. It has not been sneaked into the binary with a “trusting trust”-like technique. The bug is just an ordinary compiler bug, you do not need to be the one who put it there, it can be a known, published bug and have already been fixed in the compiler&#x27;s development version (although you can also have found the compiler bug yourself and have omitted to report it for maximum sneakiness).<p>Re-compiling the compiler does not make the bug go away. Compiling GCC with TCC does not fix bugs in GCC (otherwise people would be doing it more often).