[alwaysbeconsing]

One way to look at it (and I am not sure if this is correct, but it may be what the essay author meant) is to not treat the `unreachable` as affecting the presence of the decision, but only the result of the decision. If `unreachable` was replaced by a normal statement, we'd have:

    if (argc <= 2)
        do_something();
    else
        return printf("%s: we see %s", argv[0], argv[1]);

So the `return printf` is executed when `argc` is greater than 2. If we remove just the body of the first branch:

    if (argc <= 2)
        ;
    else
        return printf("%s: we see %s", argv[0], argv[1]);

the same thing holds. And additionally when `argc <= 2`, control will move past the `if`.

Under this view, if the `unreachable` won't cause the entire removal of the `if`, the compiler will produce the equivalent of:

    if (argc > 2)
        return printf("%s: we see %s", argv[0], argv[1]);

    return puts("this should never be reached")

Again, I don't say this is the correct interpretation, but it is one possibility, that would have to be ruled out by other parts of the standard.

[Dylan16807]

I understand that interpretation, but that's what the end of my comment is about. If we treat unreachable as affecting the block it's in, but pretend it's not there for control flow, then the two versions of the code do different things. That's confusing and hard to preserve.