c++copy-elisionnrvo

Is NRVO valid with exception throwing in body?

I am looking to understand the limitations of NRVO in C++. Would a function with an initial named declaration and a single return be optimised for NRVO and elide T val, even though the function myFunc() has a throwing potential?

T myFunc(bool toThrow) {
    T val;

    if (toThrow) {
        throw std::exception();
    }

    // Do other things here.

    return val;
}
Solution

  • I tested a few versions of your code on C++ Insights and Compiler Explorer.

    The short answer is yes, the compiler will most likely use NRVO.