typeof2.c

this is a gcc file, you can download it and learn its usetility, for further detail please look at t

// Test typeof with __asm redirection
// { dg-do compile }
// { dg-options "-O2" }

extern "C" {
  extern int foo1;
  extern int foo1 __asm ("bar1");
  int foo1 = 1;

  extern int foo2 (int);
  extern int foo2 (int) __asm ("bar2");
  int foo2 (int x)
  {
    return x;
  }

  extern int foo3;
  extern __typeof (foo3) foo3 __asm ("bar3");
  int foo3 = 1;

  extern int foo4 (int);
  extern __typeof (foo4) foo4 __asm ("bar4");
  int foo4 (int x)
  {
    return x;
  }
}

// { dg-final { scan-assembler-not "foo" } }