What are some examples of data races in programming?

What are some examples of data races in programming?

Data races occur when two or more threads access shared data simultaneously, and at least one thread modifies it. For example, if two threads increment a shared counter without proper synchronization, it can lead to inconsistent results.

Can you give me a specific code example?

Sure! Here's a simple example in C++:

#include <iostream>
#include <thread>

int counter = 0;

void increment() {
    for (int i = 0; i < 1000; ++i) {
        ++counter;
    }
}

int main() {
    std::thread t1(increment);
    std::thread t2(increment);
    t1.join();
    t2.join();
    std::cout << "Final counter value: " << counter << std::endl;
}

In this code, both threads increment the counter variable without synchronization, leading to a data race.

What are the consequences of data races?

Consequences of data races include unpredictable behavior, corrupted data, crashes, and difficult-to-debug issues. It can lead to inconsistent application states.

How can I prevent data races?

You can prevent data races by using synchronization mechanisms like mutexes, locks, or atomic operations to ensure that only one thread accesses shared data at a time.