Issue #1131: Checker: a branch ending in process::exit does not end the flow (NK2105 on a value moved there)

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ready · opened 2026-11-01 · updated 2026-11-01 · 0 comments

ADR-343 D1 says process::exit(code) ends main immediately. The move checker does not treat the call as diverging, though. A value moved in an if branch that ends with process::exit(…) still counts as moved after the branch.

Probe:

use std::process
fn take(xs: Vec[String]) {}
fn main() throws {
    let s = process::run("echo", ["a"]).stdout.trim().clone()
    if s.len() > 5 {
        take([s])
        process::exit(2)
    }
    take([s])   // NK2105: `s` moved
}

The probe compiles once you add an explicit return after process::exit(2). I found this while writing scripts/pre-push.nika, which was restructured so it does not depend on this.

To build:

• Make the checker treat process::exit(…) in main as ending the flow, the way return does (ADR-343 D1). That covers moves, definite assignment and the end-of-branch type.
• Add a test in tests/compiler/ from the probe above, with no return after the exit.

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