Region budget exceeded

Meaning

Converged analysis estimates that a named region needs more bytes than its asserted pin(N) budget.

The budget is a compile-time AIF assertion for that region, not a process-wide memory limit or a request to truncate allocation.

Why it happens

Allocation sites were added, inferred sizes increased, ownership now keeps data in the region longer, or an earlier budget was chosen without analysis evidence.

Invalid code

fn main() -> Int {
    region work pin(1) {
        let text = "allocation"
        println(text)
    }
    return 0
}

Whether a minimal illustration exceeds the budget depends on inference details; the diagnostic is issued only after a converged estimate proves the claim false.

Correct code

fn main() -> Int {
    region work {
        let text = "allocation"
        println(text)
    }
    return 0
}

Common fixes

Remove the budget, increase it using measured evidence, reduce region allocations, or split work across regions. Do not use the budget as an optimization hint; it is an assertion.

Opaque foreign allocations and runtime overhead may not be included, so passing the compiler budget is not proof of total peak memory. Record the compiler/AIF version with budget-sensitive tests.