Comment by seebs
3 years ago
Someone pointed out an obvious one: You can open the file "/dev/mem" or equivalent on many Unix systems and break things horribly, and rust can't tell that you're doing it or stop you. Someone used this to write an unsafe-free transmute, which is probably at least two different war crimes.
I doubt the rust team will try to "fix" that.
How would anyone go about preventing you from doing that?
Keep in mind /dev/mem is just a convention, I can just mknod it at any place in the filesystem I want. I can even put a FUSE overlay on it that would turn it into a regular file instead of a device node, so you wouldn't have any possible way of telling what you're about to do.
There is no "defense" against /dev/mem, that's just something you don't do as a sane programmer.
But you can get away with that in most languages that are generally considered memory safe, so a sane interpretation of the term "memory safety" wouldn't care about that.