compiler-warning-level-4-c4100.md

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Learn more about: Compiler Warning (level 4) C4100	Compiler Warning (level 4) C4100	11/04/2016	C4100	C4100	478ed97d-e502-49e4-9afb-ac2a6c61194b

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 Microsoft 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()
{
   func(1);
}