Concurrency with std::jthread

What you'll walk away with

Explain the type, lifetime, and runtime behavior of Concurrency with std::jthread
Use warnings and sanitizers to test failure cases
Write modern and safer C++

Concurrency correctness depends on shared mutable state, synchronization, cancellation, and thread lifetime. Use std::jthread automatic joining and stop tokens, and define ownership or locking so data races cannot occur.

Build a Complete Mental Model

Apply It in Modern C++

Build an original Concurrency with std::jthread example with `-std=c++23 -Wall -Wextra -Wpedantic` and test empty, boundary, invalid, and failure cases. Run lifetime-sensitive code under AddressSanitizer and UndefinedBehaviorSanitizer.

After This Lesson

Explain the ownership and lifetime contract
Build in C++23 mode with no warnings
Run a boundary or failure test under a sanitizer

cpp

#include <iostream>
#include <stop_token>
#include <thread>

int main() {
    std::jthread worker([](std::stop_token) { std::cout << "task complete\n"; });
}

You should see

task complete

Try It Yourself

Memory and Safety Warning

Assuming one correct output proves lifetime, bounds, ownership, and undefined behavior are all correct.

C++ Multithreading Reference — cppreference

Easy traps

Assuming one correct output proves lifetime, bounds, ownership, and undefined behavior are all correct.
Assuming a raw pointer or iterator remains valid after its owning container or resource changes.

Hands-on Exercise

You'll know it worked when: task complete