What Rust Can Do That Other Languages Can't

Re:What Rust Can Do That Other Languages Can't by orf on Monday February 06, 2017 @03:57AM (#13577724)

I'd hope someone with that much experience would be able to grok at least some of it? I guess it isn't explained that well though.

As I understand it, if you have a structure that has a pointer to something (like a User struct pointing to an array of permissions or some such), and the memory pointed to will be freed when the structure is freed.

There is a case where code can keep a reference to this pointer around longer than the user struct it belongs to, so when code tries to use it it references an invalid pointer. This is bad. Rust takes care of this in some clever ways, so you cant have a pointer/reference that outlives it's parent.

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Re:What Rust Can Do That Other Languages Can't by tatterdemalion on Monday February 06, 2017 @04:00AM (#13577743)

You've missed a critical point in the article: the structure does not have a pointer to something it has a member inline within its stack representation.

Any garbage collector could (with some overhead) prevent invalid memory access when we're talking about an object with a pointer to another object. Rust is able to validate the correctness of pointers to offsets within the stack representation of an object.

(Rust also validates the correctness of references to heap allocated objects as well, of course!)

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