Throwing from a destructor in ScopeGuard is equivalent to calling a function that can throw in a catch or finally block, which you can do in most (any?) languages with exceptions. This no exceptions in destructors "issue" is not a C++ issue. It's a fundamental issue in error propagation. What do you do when propagating error correctly, causes a new error? You can't propagate the first error, because you can't do it correctly. You can't propagate the second error, because that would mean dropping the first.

Classic example is logging an error on failure. This means calling a logging function in the catch block, and then letting the exception propagate. But what if the call to the logging function fails? In Java, coded naively you'd simply drop the original exception. Usually that's not what you want.

You can examine the issue with error codes, it's not any better.