Compiler Warning (level 4) C4100


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The latest version of this topic can be found at Compiler Warning (level 4) C4100.

identifier' : unreferenced formal parameter

The formal parameter is not referenced in the body of the function. The unreferenced parameter is ignored.

C4100 can also be issued when code calls a destructor on a otherwise unreferenced parameter of primitive type. This is a limitation of the Visual C++ compiler.

The following sample generates C4100:

// C4100.cpp  
// compile with: /W4  
void func(int i) {   // C4100, delete the unreferenced parameter to  
                     //resolve the warning  
   // i;   // or, add a reference like this  
int main()