rustAsync race conditionMedium

Thread join omitted before parent process returns

Time: 0:00

BugFind the bug and fix the code

What it should do

Spawn thread to compute value and return result. Example: spawn_and_collect(5) -> 10

What happens instead

Thread dropped without join, result lost or thread killed prematurely

use std::thread;

fn spawn_and_collect(val: i32) -> i32 {
    let handle = thread::spawn(move || {
        val * 2
    });
    // Dropping handle without joining terminates thread or drops result
    val
}

fn main() {
    println!("{}", spawn_and_collect(5));
}

Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).

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This bug belongs to the async and race conditions pattern

A missing await, unbuffered channel deadlocks, ConcurrentModificationException, and data races under load.

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use std::thread; fn spawn_and_collect(val: i32) -> i32 { let handle = thread::spawn(move || { val * 2 }); // Dropping handle without joining terminates thread or drops result val } fn main() { println!("{}", spawn_and_collect(5)); }

Thread join omitted before parent process returns

What it should do

What happens instead

More async and race conditions to practise

Thread join omitted before parent process returns

What it should do

What happens instead

More async and race conditions to practise