C++ RTTI和LLVM RTTI使用方法和原理解析 - 知乎 - 知乎专栏

WebAnswer: Your base class does not have any virtual method, and therefore it is not polymorphic, and only polymorphic classes are those that generate a vtable (the table that stores, for each memory address at runtime, the derived type with which it is created the object, required for the dynamic_cast ). If you don't need any particular function ... WebFeb 27, 2013 · As your compiler says, your type A is not polymorphic. You should add a virtual function to it. For instance, a virtual destructor could be a good choice: struct A { virtual ~A() { } }; // ^^^^^ This makes A a polymorphic type struct B : A {}; int main() … shanti instrument

WebApr 7, 2024 · This of course requires that the classes really are polymorphic, and have at least one virtual function (which should be the destructor). Share Improve this answer WebEven though both are pointers of type CBase*, pba points to an object of type CDerived, while pbb points to an object of type CBase.Thus, when their respective type-castings are performed using dynamic_cast, pba is pointing to a full object of class CDerived, whereas pbb is pointing to an object of class CBase, which is an incomplete object of class … WebJun 8, 2024 · Solution 1. You need to make A polymorphic, which you can do by adding a virtual destructor or any virtual function:. struct A { virtual ~A() = default; }; or, before C++11, struct A { virtual ~A() {} }; Note that a polymorphic type should have a virtual destructor anyway, if you intend to safely call delete on instances of a derived type via a pointer to … shanti international