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rust.unbounded_recursion

Stability High

Detects recursive functions without depth limits that can cause stack overflow.

Why It Matters

Unbounded recursion:

Stack overflow — Program crashes
No recovery — SIGSEGV is fatal
Hard to debug — Happens deep in call stack

Example

// ❌ Before (unbounded recursion)
fn traverse(node: &Node) {
    process(node);
    for child in &node.children {
        traverse(child); // No depth limit!
    }
}

// ✅ After (with depth limit)
fn traverse(node: &Node, depth: usize) -> Result<(), Error> {
    if depth > 100 {
        return Err(Error::MaxDepthExceeded);
    }
    process(node);
    for child in &node.children {
        traverse(child, depth + 1)?;
    }
    Ok(())
}

What Unfault Detects

Recursive functions without base case
Missing depth counters
Self-referential data traversal

Auto-Fix

Unfault adds depth parameters and checks.