Compiler Error C2570


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'identifier' : union cannot have base classes

A union derives from a class, structure, or union. This is not allowed. Declare the derived type as a class or structure instead.

The following sample generates C2570:

// C2570.cpp  
// compile with: /c  
class base {};  
union hasPubBase : public base {};   // C2570  
union hasNoBase {};   // OK