ubrustc: Unborrowed rustc

This is rustc with the borrow checker disabled. I wrote it in like, 30 minutes because this tweet made me laugh.

Example

// main.rs
fn main() {
    let s = "hi, world".to_string();
    let msg: &str = &s;
    drop(s);
    println!("Hello, memory corruption: {msg:?}");
}

# <install using steps in `Usage` section>
$ RUSTC=ubrustc cargo run
   Compiling ubrustc-verify v0.1.0 (/Users/thom/scratch/ubrustc-verify)
    Finished dev [unoptimized + debuginfo] target(s) in 0.12s
     Running `target/debug/ubrustc-verify`
Hello, memory corruption: "\0\0\0\0\0\0\0\0\0"

Usage

You will need to be on a nightly rust (the toolchain from 2023-02-09 is known to work), and have the rustc-dev and llvm-tools-preview components installed.

Then, you can either do ./build.sh to build the binary, which will place it somewhere inside target/*, or ./build.sh install. If you're on Windows, IDK (it shouldn't be hard to install, but you likely need to set the rpath right).

Once it's installed, you use it by setting the RUSTC environment variable to ubrustc when running cargo.

Please don't use this in production. I will not be maintaining it.

Acknowledgements

Apologies to Will Crichton.