Handling stdafx.h in cross-platform code

You're best off using precompiled headers still for fastest compilation.

You can use precompiled headers in gcc as well. See here.

The compiled precompiled header will have an extension appended as .gch instead of .pch.

So for example if you precompile stdafx.h you will have a precompiled header that will be automatically searched for called stdafx.h.gch anytime you include stdafx.h

Example:

stdafx.h:

#include <string>
#include <stdio.h>

a.cpp:

#include "stdafx.h"
int main(int argc, char**argv)
{
  std::string s = "Hi";
  return 0;
}

Then compile as:

> g++ -c stdafx.h -o stdafx.h.gch
> g++ a.cpp
> ./a.out

Your compilation will work even if you remove stdafx.h after step 1.

I used option 3 last time I needed to do this same thing. My project was pretty small but this worked wonderfully.