Compiler Warning (level 4) C4625


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The latest version of this topic can be found at Compiler Warning (level 4) C4625.

derived class' : copy constructor was implicitly defined as deleted because a base class copy constructor is inaccessible or deleted

A copy constructor was deleted or not accessible in a base class and was therefore not generated for a derived class. Any attempt to copy an object of this type will cause a compiler error.

This warning is off by default. See Compiler Warnings That Are Off by Default for more information.

The following sample generates C4625 and shows how to fix it.

// C4625.cpp  
// compile with: /W4 /c  
#pragma warning(default : 4625)  
struct A {  
   A() {}  
   A(const A&) {}  
struct C : private virtual A {};  
struct B :  C {};   // C4625 no copy constructor  
struct D : A {};  
struct E :  D {};   // OK