Avian’s Blog

Reflections on Trusting Trust by Ken Thompson, one of the original authors of Unix, shows in a very nice way how you can't trust any binary if you can't trust the compiler that was used to compile it.

I think the part about the concept of a "learning" program is worth reading alone. I knew compilers are usually compiled by themselves (take GCC for example - it seems that the basic sign that a compiler is actually usable is that it can compile itself), but I never looked at this practice from the view point presented in the article.