Compiler Warning (level 4) C4481


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The latest version of this topic can be found at Compiler Warning (level 4) C4481.

nonstandard extension used: override specifier 'keyword'

A keyword was used that is not in the C++ standard, for example, one of the override specifiers that also works under /clr. For more information, see,

The following sample generates C4481.

// C4481.cpp  
// compile with: /W4 /c  
class B {  
   virtual void f(unsigned);  
class C : B {  
   void f(unsigned) override;   // C4481  
   void f2(unsigned);