w8080 Warning message doesn't operate with AnsiString

Hi,

I've noticed in BCB6 that if Project->Options->Compiler->All warnings
have been selected, the w8080 warning message: 'identifier' declared
but never used, is not functioning with AnsiString identifiers.
For example:

void MyFunc()
{
  int test;

  // code here without any reference to test

Quote
}

raises the w8080 warning, but:

void MyFunc()
{
  AnsiString test;

  // code here without any reference to test

Quote
}

does not.
Why?

Thank you.

Res