Nope, I agree that's a volatile read, and indeed the web page doesn't emit the appropriate intrinsic, nor indeed do small modifications that result in a read of the pointer, cause the intrinsic to be used as I'd anticipated.

Definitely something to be wary of. I assure you the c2rust source code does know about volatile access and Rust's intrinsics (I was looking at that code for other reasons), so if you work with this stuff I'd encourage talking to the people who wrote it to find out what the situation is.