Using large Field's in numeric generics fails with "array length too large"

[michaeljklein]

Aim

Attempted to use a Field larger than u32::MAX as a numeric generic:

global A: Field = 4294967297;

fn foo<let A: Field>() { }

fn main() {
    let C = foo::<A>();
}

Expected Behavior

Expected the program to compile successfully or fail with a clear error

Bug

Compilation fails with a message that the Field is too large to be an array length, but it's not used as an array length:

❯ ~/.nargo/bin/nargo compile
warning: unused variable C
   ┌─ src/main.nr:12:9
   │
12 │     let C = foo::<A>();
   │         - unused variable 
   │

error: Integer too large to be evaluated to an array-length
  ┌─ src/main.nr:7:19
  │
7 │ global A: Field = 4294967297;
  │                   ---------- Array-lengths may be a maximum size of usize::MAX, including intermediate calculations
  │

Aborting due to 1 previous error

To Reproduce

Workaround

None

Workaround Description

No response

Additional Context

No response

Project Impact

None

Blocker Context

No response

Nargo Version

nargo version = 0.34.0 noirc version = 0.34.0+5598059576c6cbc72474aff4b18bc5e4bb9f08e1 (git version hash: 5598059, is dirty: false)

NoirJS Version

No response

Proving Backend Tooling & Version

No response

Would you like to submit a PR for this Issue?

None

Support Needs

No response

[michaeljklein]

As a noirc_frontend test:

#[test]
fn use_global_larger_than_u32_as_generic() {
    let src = r#"
        // 2^32 + 1
        global A: Field = 4294967297;

        fn foo<let A: Field>() { }

        fn main() {
            let C = foo::<A>();
        }
    "#;

    let errors = get_program_errors(src);

    // TODO cleanup
    dbg!(&errors);

    assert_eq!(errors.len(), 0);
}