title: Make g++ compile C using gcc rules
body: <p>I have a .cpp source file that contains both C and C++ code. The C code does not compile using g++ so I need to use gcc.</p>
  
  <p>Using <code>extern "C" {}</code> does not work because that's just to tell the compiler how to handle the function names, I want g++ to behave like gcc entirely for one portion of the code, and like g++ for another.</p>
  
  <p>I know I could just put them on separate files, but then I would have to create a header for the file with the C code to be able to use it in the other C++ file and that is what I'm trying to avoid. I don't want those functions visible to anyone other than that C++ code.</p>
  
  <p>Does that make sense? Is this even possible? Thanks!</p>