Out optionalclass is not generating valid code in C++ implementation.

If there is an out optionalclass value, the code generator creates a base result variable:
IBase * pBaseHandlerInstance(nullptr);

This leads to a compile error of the implementation. The class should be the correct output class, like
ISignalHandler * pBaseHandlerInstance(nullptr);

Locate the code-generator logic that emits pBaseHandlerInstance and reproduce the case with an out optionalclass value. Verify that generated C++ declares the concrete output class, such as ISignalHandler, instead of IBase, and that the implementation compiles.

Written by the indexing model from the issue text.