--- foo.c ---

#include<stdio.h>

#define X(a,b)float a##__LINE__(int x,int y){b;}
#include "bar.c"

int main() {
#define X(a,b)printf(#a" = %f\n",a##__LINE__(2,3))
#include "bar.c"
}


--- bar.c ---
X(foo,
  {
	  return x+y+2;
  });

X(bar, { return x*y; });

X(qux,
  {
	  float yy=y;
	  return x/yy;
  });