Error when casting mut to const pointer

[maximebuyse]

use std::ptr::NonNull;


pub fn g(x: * const i32) -> i32 {
    1
}


unsafe fn f(x: NonNull<i32>) -> i32 {
    g(x.as_ptr())
}

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This gives:

error: [HAX0002] (AST import) Fatal error: something we considered as impossible occurred! Please report this by submitting an issue on GitHub!
Details: Pointer, with [cast] being Types.MutToConstPointer
  --> src/lib.rs:10:7
   |
10 |     g(x.as_ptr())

and

error: [HAX0002] (RefMut) Fatal error: something we considered as impossible occurred! Please report this by submitting an issue on GitHub!
Details: expected an arrow type here
  --> src/lib.rs:10:1
   |
10 |     g(x.as_ptr())

I also found the same kind of error with Details: Pointer, with [cast] being Types.UnsafeFnPointer

[W95Psp]

Thanks, that's the engine side of #1057 I believe!

[Nadrieril]

There are no constants involved here though

[github-actions[bot]]

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[W95Psp]

There is no unsafe needed here:

use std::ptr::NonNull;

fn g(x: * const i32) -> i32 {
    1
}

fn f(x: NonNull<i32>) -> i32 {
    g(x.as_ptr())
}

Open this code snippet in the playground

Also, here is a further minimization:

fn g(x: *const ()) { }
fn f(x: *mut ()) {
    g(x)
}

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We should implement everything from https://doc.rust-lang.org/beta/nightly-rustc/rustc_middle/ty/adjustment/enum.PointerCoercion.html#variant.ClosureFnPointer, via calls to dedicated Rust_primitive cast functions.