Printing name and value of a macro

I have a C program with a lot of optimizations that can be enabled or disabled with #defines. When I run my program, I would like to know what macros have been defined at compile time.

So I am trying to write a macro function to print the actual value of a macro. Something like this:

SHOW_DEFINE(X){
  if( IS_DEFINED(X) )
      printf("%s is defined and as the value %dn", #X, (int)X);
  else
      printf("%s is not definedn", #X);
}

However I don't know how to make it work and I suspect it is not possible, does anyone has an idea of how to do it?

(Note that this must compile even when the macro is not defined!)