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Add ifdefs to fork05 to all it to compile and run on all platforms.
The test will only be performed on ix86 systems.
On all other systems, the program will always exit successfully.

/*
 * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
 * Portions Copyright (c) 2000 Ulrich Drepper
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 * 
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * 
 * Further, this software is distributed without any warranty that it is
 * free of the rightful claim of any third person regarding infringement
 * or the like.  Any license provided herein, whether implied or
 * otherwise, applies only to this software file.  Patent licenses, if
 * any, provided herein do not apply to combinations of this program with
 * other software, or any other product whatsoever.
 * 
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
 * 
 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
 * Mountain View, CA  94043, or:
 * 
 * http://www.sgi.com 
 * 
 * For further information regarding this notice, see: 
 * 
 * http://oss.sgi.com/projects/GenInfo/NoticeExplan/
 */
/* $Id: fork05.c,v 1.3 2001/02/11 17:11:24 alaffin Exp $ */
/**********************************************************
 *
 *    Linux Test Project - Silicon Graphics, Inc.
 *    
 *    TEST IDENTIFIER	: fork05
 *
 *    EXECUTED BY	: anyone
 *
 *    TEST TITLE	: Make sure LDT is propagated correctly
 *
 *    TEST CASE TOTAL	: 1
 *
 *    CPU TYPES		: i386
 *
 *    AUTHORS		: Ulrich Drepper
 *			  Nate Straz
 *
 *On Sat, Aug 12, 2000 at 12:47:31PM -0700, Ulrich Drepper wrote:
 *> Ever since the %gs handling was fixed in the 2.3.99 series the
 *> appended test program worked.  Now with 2.4.0-test6 it's not working
 *> again.  Looking briefly over the patch from test5 to test6 I haven't
 *> seen an immediate candidate for the breakage.  It could be missing
 *> propagation of the LDT to the new process (and therefore an invalid
 *> segment descriptor) or simply clearing %gs.
 *> 
 *> Anyway, this is what you should see and what you get with test5:
 *> 
 *> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *> a = 42
 *> %gs = 0x0007
 *> %gs = 0x0007
 *> a = 99
 *> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *> 
 *> This is what you get with test6:
 *> 
 *> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *> a = 42
 *> %gs = 0x0007
 *> %gs = 0x0000
 *> <SEGFAULT>
 *> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *> 
 *> If somebody is actually creating a test suite for the kernel, please
 *> add this program.  It's mostly self-contained.  The correct handling
 *> of %gs is really important since glibc 2.2 will make heavy use of it.
 *> 
 *> - -- 
 *> - ---------------.                          ,-.   1325 Chesapeake Terrace
 *> Ulrich Drepper  \    ,-------------------'   \  Sunnyvale, CA 94089 USA
 *> Red Hat          `--' drepper at redhat.com   `------------------------
 *> 
 *> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *
 *********************************************************/
#include <stdio.h>

#if defined(linux) && defined(__i386__)
#include <fcntl.h>
#include <unistd.h>
#include <sys/wait.h>

struct modify_ldt_ldt_s
{
  unsigned int entry_number;
  unsigned long int base_addr;
  unsigned int limit;
  unsigned int seg_32bit:1;
  unsigned int contents:2;
  unsigned int read_exec_only:1;
  unsigned int limit_in_pages:1;
  unsigned int seg_not_present:1;
  unsigned int useable:1;
  unsigned int empty:25;
};

asm("	.type modify_ldt,@function
modify_ldt:
	push   %ebx
	mov    0x10(%esp,1),%edx
	mov    0xc(%esp,1),%ecx
	mov    0x8(%esp,1),%ebx
	mov    $0x7b,%eax
	int    $0x80
	pop    %ebx
	ret");

int a = 42;

int
main ()
{
  struct modify_ldt_ldt_s ldt0;
  int lo;
  pid_t pid;
  int res;

  ldt0.entry_number = 0;
  ldt0.base_addr = (long) &a;
  ldt0.limit = 4;
  ldt0.seg_32bit = 1;
  ldt0.contents = 0;
  ldt0.read_exec_only = 0;
  ldt0.limit_in_pages = 0;
  ldt0.seg_not_present = 0;
  ldt0.useable = 1;
  ldt0.empty = 0;

  modify_ldt (1, &ldt0, sizeof (ldt0));

  asm ("movw %w0, %%gs" : : "q" (7));

  asm ("movl %%gs:0, %0" : "=r" (lo));
  printf ("a = %d\n", lo);

  asm ("pushl %%gs; popl %0" : "=q" (lo));
  printf ("%%gs = %#06hx\n", lo);

  asm ("movl %0, %%gs:0" : : "r" (99));

  pid = fork ();

  if (pid == 0) {
      asm ("pushl %%gs; popl %0" : "=q" (lo));
      printf ("%%gs = %#06hx\n", lo);

      asm ("movl %%gs:0, %0" : "=r" (lo));
      printf ("a = %d\n", lo);

      exit (lo != 99);
  } else {
      waitpid (pid, &res, 0);
  }

  return WIFSIGNALED(res);
}

#else /* if defined(linux) && defined(__i386__) */

int
main()
{
  printf("%%gs test only for ix86\n");

  /*
   * should be successful on all non-ix86 platforms.
   */
  return(0);
}

#endif /* if defined(linux) && defined(__i386__) */