Why does the compiler mark destructors with noexcept?

In C++, destructors are considered noexcept(true) by default, meaning they should not throw exceptions. This is important because if a destructor throws an exception during the handling of another exception (for example, when exiting a try block), the program will call std::terminate().

Marking a destructor as noexcept allows the compiler and standard library to optimize the code and ensure safety when destroying objects. If a destructor might throw an exception, it must be explicitly specified, but this is highly discouraged.

Example:

class MyClass {
public:
    ~MyClass() noexcept { // ensure that no exceptions are thrown
        // resource cleanup
    }
};