Throwing Non-Exceptions with std::throw_with_nested()

If you pass a non-exception type to std::throw_with_nested(), the behavior is undefined. The C++ standard requires that the argument to std::throw_with_nested() be derived from std::exception.

For example, this code has undefined behavior:

1try {
2  std::throw_with_nested(42);
3} catch(...) {
4// undefined behavior
5}

To properly use std::throw_with_nested(), ensure you only pass it exceptions:

1try {
2  std::throw_with_nested(
3    std::runtime_error{"Error"});  
4} catch (...) {
5  // OK, runtime_error derives from std::exception
6}