Why is this an issue?
When entering a critical section the program holds a lock that can be hold by a single entity at a time. It is then recommended that the critical
section is reduced to the minimum required and executed without any interruption.
Noncompliant code example
void f() {
std::mutex m;
// ...
m.lock();
// ...
sleep(1); // Noncompliant
// ...
m.unlock();
}