Array get on empty array panics at compile time

[michaeljklein]

Aim

Attempted to compile a program where an empty array is accessed within a non-executed if statement:

fn main(x: pub bool) {
    let empty_array: [Field; 0] = [];

    if x {
        let _ = empty_array[0];
    }

    // the same error occurs when the `if` block is elided:
    // let _ = empty_array[0];

    // and when the index is dynamic (x: pub u32)
    // if x == 0 {
    //     let _ = empty_array[x];
    // }

    // and when the array is dynamic (xs: pub [Field; 0])
    // let empty_array: [Field; 0] = xs;
}

Expected Behavior

Expected the program to compile successfully

Bug

nargo compile panics during the DIE pass:

The application panicked (crashed).
Message:  attempt to divide by zero
Location: compiler/noirc_evaluator/src/ssa/opt/die.rs:386

This is a bug. We may have already fixed this in newer versions of Nargo so try searching for similar issues at https://github.com/noir-lang/noir/issues/.
If there isn't an open issue for this bug, consider opening one at https://github.com/noir-lang/noir/issues/new?labels=bug&template=bug_report.yml

To Reproduce

Workaround

Yes

Workaround Description

• Locate empty array
• Replace with the singleton array [std::mem::zeroed()]
• Add a new parameter to ignore the std::mem::zeroed() when needed

Additional Context

No response

Project Impact

None

Blocker Context

No response

Nargo Version

nargo version = 0.33.0 noirc version = 0.33.0+712468a08dd95eaed42345320e8c3e6751e88c47 (git version hash: 712468a, 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