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c++c++11unused-variables

Unused parameter in c++11

In c++03 and earlier to disable compiler warning about unused parameter I usually use such code:

#define UNUSED(expr) do { (void)(expr); } while (0)

For example 

int main(int argc, char *argv[])
{
    UNUSED(argc);
    UNUSED(argv);

    return 0;
}

But macros are not best practice for c++, so. Does any better solution appear with c++11 standard? I mean can I get rid of macros?

Thanks for all!

Solution

  • I have used a function with an empty body for that purpose:

    template <typename T>
void ignore(T &&)
{ }

void f(int a, int b)
{
  ignore(a);
  ignore(b);
  return;
}

    I expect any serious compiler to optimize the function call away and it silences warnings for me.