llvm-gcc-4.0/gcc/testsuite/gcc.dg/991209-1.c

/* { dg-do compile { target i?86-*-* } } */
/* { dg-options "-ansi -pedantic" } */

int foo ()
{
  return 1;
}

register char *stack_ptr __asm ("%esp"); /* { dg-warning "warning: file-scope declaration of 'stack_ptr' specifies 'register'" } */