gdb:

2008-11-27  Tristan Gingold  <gingold@adacore.com>

	* NEWS: Add entry for new native configuration: Darwin.
	* configure.host: Add Darwin host.
	* configure.tgt: Add Darwin target.
	* defs.h (enum gdb_osabi): Add GDB_OSABI_DARWIN.
	* osabi.c (gdb_osabi_names): Add name for Darwin abi.
	* i386-darwin-nat.c: New file.
	* i386-darwin-tdep.c: New file.
	* machoread.c: New file.
	* darwin-nat-info.c: New file.
	* darwin-nat.c: New file.
	* darwin-nat.h: New file.
	* darwin.defs: New file.
	* config/i386/darwin.mh: New file.

gdb/doc:
2008-11-27  Tristan Gingold  <gingold@adacore.com>

	* gdb.texinfo (Darwin): Document Darwin specific features.

17 files changed, 3731 insertions, 0 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 84aff02e03f..843c19435c9 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,19 @@
+2008-11-27  Tristan Gingold  <gingold@adacore.com>
+
+	* NEWS: Add entry for new native configuration: Darwin.
+	* configure.host: Add Darwin host.
+	* configure.tgt: Add Darwin target.
+	* defs.h (enum gdb_osabi): Add GDB_OSABI_DARWIN.
+	* osabi.c (gdb_osabi_names): Add name for Darwin abi.
+	* i386-darwin-nat.c: New file.
+	* i386-darwin-tdep.c: New file.
+	* machoread.c: New file.
+	* darwin-nat-info.c: New file.
+	* darwin-nat.c: New file.
+	* darwin-nat.h: New file.
+	* darwin.defs: New file.
+	* config/i386/darwin.mh: New file.
+
 2008-11-26  Tristan Gingold  <gingold@adacore.com>
 
 	* MAINTAINERS: Add myself for write after approval privileges.
diff --git a/gdb/NEWS b/gdb/NEWS
index 86125c9d639..657c20408da 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -172,6 +172,10 @@ macro undef
   These allow macros to be defined, undefined, and listed
   interactively.
 
+* New native configurations
+
+x86/x86_64 Darwin		i[34567]86-*-darwin*
+
 * New targets
 
 x86 DICOS			i[34567]86-*-dicos*
diff --git a/gdb/config/i386/darwin.mh b/gdb/config/i386/darwin.mh
new file mode 100644
index 00000000000..ed49d7dec80
--- /dev/null
+++ b/gdb/config/i386/darwin.mh
@@ -0,0 +1,10 @@
+# Host: IA86 running Darwin
+
+NATDEPFILES = fork-child.o machoread.o darwin-nat.o excServer.o \
+     i386-darwin-nat.o i386-nat.o amd64-nat.o darwin-nat-info.o
+
+# Trick so that excServer.c is not the default target!
+_all: all
+
+excServer.c: darwin.defs
+	/usr/bin/mig -I. $<
diff --git a/gdb/configure.host b/gdb/configure.host
index 672920de851..b9ed7ae14f6 100644
--- a/gdb/configure.host
+++ b/gdb/configure.host
@@ -62,6 +62,8 @@ esac
 
 case "${host}" in
 
+*-*-darwin*)		gdb_host=darwin ;;
+
 alpha*-*-osf[3456789]*)	gdb_host=alpha-osf3 ;;
 alpha*-*-linux*)	gdb_host=alpha-linux ;;
 alpha*-*-freebsd* | alpha*-*-kfreebsd*-gnu)
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index 95556f8e067..b9cd21bdc05 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -145,6 +145,11 @@ hppa*-*-*)
 	gdb_target_obs="hppa-tdep.o"
 	;;
 
+i[34567]86-*-darwin*)
+	# Target: Darwin/i386
+	gdb_target_obs="amd64-tdep.o i386-tdep.o i387-tdep.o \
+			i386-darwin-tdep.o"
+	;;
 i[34567]86-*-dicos*)
 	# Target: DICOS/i386
 	gdb_target_obs="i386-tdep.o i387-tdep.o \
diff --git a/gdb/darwin-nat-info.c b/gdb/darwin-nat-info.c
new file mode 100644
index 00000000000..db7cb05a967
--- /dev/null
+++ b/gdb/darwin-nat-info.c
@@ -0,0 +1,847 @@
+/* Darwin support for GDB, the GNU debugger.
+   Copyright 1997, 1998, 1999, 2000, 2001, 2002, 2008
+   Free Software Foundation, Inc.
+
+   Contributed by Apple Computer, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/* The name of the ppc_thread_state structure, and the names of its
+   members, have been changed for Unix conformance reasons.  The easiest
+   way to have gdb build on systems with the older names and systems
+   with the newer names is to build this compilation unit with the
+   non-conformant define below.  This doesn't seem to cause the resulting
+   binary any problems but it seems like it could cause us problems in
+   the future.  It'd be good to remove this at some point when compiling on
+   Tiger is no longer important.  */
+
+#include "defs.h"
+#include "symtab.h"
+#include "gdbtypes.h"
+#include "gdbcore.h"
+#include "value.h"
+#include "gdbcmd.h"
+#include "inferior.h"
+
+#include <sys/param.h>
+#include <sys/sysctl.h>
+
+#include "darwin-nat.h"
+
+#include <mach/thread_info.h>
+#include <mach/thread_act.h>
+#include <mach/task.h>
+#include <mach/vm_map.h>
+#include <mach/mach_port.h>
+#include <mach/mach_init.h>
+#include <mach/mach_vm.h>
+
+#define CHECK_ARGS(what, args) do { \
+  if ((NULL == args) || ((args[0] != '0') && (args[1] != 'x'))) \
+    error("%s must be specified with 0x...", what);		\
+} while (0)
+
+#define PRINT_FIELD(structure, field) \
+  printf_unfiltered(_(#field":\t%#lx\n"), (unsigned long) (structure)->field)
+
+#define PRINT_TV_FIELD(structure, field) \
+  printf_unfiltered(_(#field":\t%u.%06u sec\n"),	\
+  (unsigned) (structure)->field.seconds, \
+  (unsigned) (structure)->field.microseconds)
+
+#define task_self mach_task_self
+#define task_by_unix_pid task_for_pid
+#define port_name_array_t mach_port_array_t
+#define port_type_array_t mach_port_array_t
+
+static void
+info_mach_tasks_command (char *args, int from_tty)
+{
+  int sysControl[4];
+  int count, index;
+  size_t length;
+  struct kinfo_proc *procInfo;
+
+  sysControl[0] = CTL_KERN;
+  sysControl[1] = KERN_PROC;
+  sysControl[2] = KERN_PROC_ALL;
+
+  sysctl (sysControl, 3, NULL, &length, NULL, 0);
+  procInfo = (struct kinfo_proc *) xmalloc (length);
+  sysctl (sysControl, 3, procInfo, &length, NULL, 0);
+
+  count = (length / sizeof (struct kinfo_proc));
+  printf_unfiltered (_("%d processes:\n"), count);
+  for (index = 0; index < count; ++index)
+    {
+      kern_return_t result;
+      mach_port_t taskPort;
+
+      result =
+        task_by_unix_pid (mach_task_self (), procInfo[index].kp_proc.p_pid,
+                          &taskPort);
+      if (KERN_SUCCESS == result)
+        {
+          printf_unfiltered (_("    %s is %d has task %#x\n"),
+                             procInfo[index].kp_proc.p_comm,
+                             procInfo[index].kp_proc.p_pid, taskPort);
+        }
+      else
+        {
+          printf_unfiltered (_("    %s is %d unknown task port\n"),
+                             procInfo[index].kp_proc.p_comm,
+                             procInfo[index].kp_proc.p_pid);
+        }
+    }
+
+  xfree (procInfo);
+}
+
+static task_t
+get_task_from_args (char *args)
+{
+  task_t task;
+  char *eptr;
+
+  if (args == NULL || *args == 0)
+    {
+      if (darwin_inf->task == TASK_NULL)
+	printf_unfiltered (_("No inferior running\n"));
+      return darwin_inf->task;
+    }
+  if (strcmp (args, "gdb") == 0)
+    return mach_task_self ();
+  task = strtoul (args, &eptr, 0);
+  if (*eptr)
+    {
+      printf_unfiltered (_("cannot parse task id '%s'\n"), args);
+      return TASK_NULL;
+    }
+  return task;
+}
+
+static void
+info_mach_task_command (char *args, int from_tty)
+{
+  union
+  {
+    struct task_basic_info basic;
+    struct task_events_info events;
+    struct task_thread_times_info thread_times;
+  } task_info_data;
+
+  kern_return_t result;
+  unsigned int info_count;
+  task_t task;
+
+  task = get_task_from_args (args);
+  if (task == TASK_NULL)
+    return;
+
+  printf_unfiltered (_("TASK_BASIC_INFO for 0x%x:\n"), task);
+  info_count = TASK_BASIC_INFO_COUNT;
+  result = task_info (task,
+                      TASK_BASIC_INFO,
+                      (task_info_t) & task_info_data.basic, &info_count);
+  MACH_CHECK_ERROR (result);
+
+  PRINT_FIELD (&task_info_data.basic, suspend_count);
+  PRINT_FIELD (&task_info_data.basic, virtual_size);
+  PRINT_FIELD (&task_info_data.basic, resident_size);
+  PRINT_TV_FIELD (&task_info_data.basic, user_time);
+  PRINT_TV_FIELD (&task_info_data.basic, system_time);
+  printf_unfiltered (_("\nTASK_EVENTS_INFO:\n"));
+  info_count = TASK_EVENTS_INFO_COUNT;
+  result = task_info (task,
+                      TASK_EVENTS_INFO,
+                      (task_info_t) & task_info_data.events, &info_count);
+  MACH_CHECK_ERROR (result);
+
+  PRINT_FIELD (&task_info_data.events, faults);
+#if 0
+  PRINT_FIELD (&task_info_data.events, zero_fills);
+  PRINT_FIELD (&task_info_data.events, reactivations);
+#endif
+  PRINT_FIELD (&task_info_data.events, pageins);
+  PRINT_FIELD (&task_info_data.events, cow_faults);
+  PRINT_FIELD (&task_info_data.events, messages_sent);
+  PRINT_FIELD (&task_info_data.events, messages_received);
+  printf_unfiltered (_("\nTASK_THREAD_TIMES_INFO:\n"));
+  info_count = TASK_THREAD_TIMES_INFO_COUNT;
+  result = task_info (task,
+                      TASK_THREAD_TIMES_INFO,
+                      (task_info_t) & task_info_data.thread_times,
+                      &info_count);
+  MACH_CHECK_ERROR (result);
+  PRINT_TV_FIELD (&task_info_data.thread_times, user_time);
+  PRINT_TV_FIELD (&task_info_data.thread_times, system_time);
+}
+
+static void
+info_mach_ports_command (char *args, int from_tty)
+{
+  port_name_array_t names;
+  port_type_array_t types;
+  unsigned int name_count, type_count;
+  kern_return_t result;
+  int index;
+  task_t task;
+
+  task = get_task_from_args (args);
+  if (task == TASK_NULL)
+    return;
+
+  result = mach_port_names (task, &names, &name_count, &types, &type_count);
+  MACH_CHECK_ERROR (result);
+
+  gdb_assert (name_count == type_count);
+
+  printf_unfiltered (_("Ports for task 0x%x:\n"), task);
+  printf_unfiltered (_("port   type\n"));
+  for (index = 0; index < name_count; ++index)
+    {
+      mach_port_t port = names[index];
+      unsigned int j;
+      struct type_descr
+      {
+	mach_port_type_t type;
+	const char *name;
+	mach_port_right_t right;
+      };
+      static struct type_descr descrs[] =
+	{
+	  {MACH_PORT_TYPE_SEND, "send", MACH_PORT_RIGHT_SEND},
+	  {MACH_PORT_TYPE_SEND_ONCE, "send-once", MACH_PORT_RIGHT_SEND_ONCE},
+	  {MACH_PORT_TYPE_RECEIVE, "receive", MACH_PORT_RIGHT_RECEIVE},
+	  {MACH_PORT_TYPE_PORT_SET, "port-set", MACH_PORT_RIGHT_PORT_SET},
+	  {MACH_PORT_TYPE_DEAD_NAME, "dead", MACH_PORT_RIGHT_DEAD_NAME}
+	};
+
+      printf_unfiltered (_("%04x: %08x "), port, types[index]);
+      for (j = 0; j < sizeof(descrs) / sizeof(*descrs); j++)
+	if (types[index] & descrs[j].type)
+	  {
+	    mach_port_urefs_t ref;
+	    kern_return_t ret;
+
+	    printf_unfiltered (_(" %s("), descrs[j].name);
+	    ret = mach_port_get_refs (task, port, descrs[j].right, &ref);
+	    if (ret != KERN_SUCCESS)
+	      printf_unfiltered (_("??"));
+	    else
+	      printf_unfiltered (_("%u"), ref);
+	    printf_unfiltered (_(" refs)"));
+	  }
+      
+      if (task == task_self ())
+	{
+	  if (port == task_self())
+	    printf_unfiltered (_(" gdb-task"));
+	  else if (port == darwin_host_self)
+	    printf_unfiltered (_(" host-self"));
+	  else if (port == darwin_not_port)
+	    printf_unfiltered (_(" gdb-notifier"));
+	  else if (port == darwin_ex_port)
+	    printf_unfiltered (_(" gdb-exception"));
+	  else if (port == darwin_port_set)
+	    printf_unfiltered (_(" gdb-port_set"));
+	  else if (darwin_inf && port == darwin_inf->task)
+	    printf_unfiltered (_(" inferior-task"));
+	  else if (darwin_inf && darwin_inf->threads)
+	    {
+	      int k;
+	      thread_t t;
+	      for (k = 0; VEC_iterate(thread_t, darwin_inf->threads, k, t); k++)
+		if (port == t)
+		  {
+		    printf_unfiltered (_(" inferior-thread for 0x%x"),
+				       darwin_inf->task);
+		    break;
+		  }
+	    }
+	}
+      printf_unfiltered (_("\n"));
+    }
+
+  vm_deallocate (task_self (), (vm_address_t) names,
+                 (name_count * sizeof (mach_port_t)));
+  vm_deallocate (task_self (), (vm_address_t) types,
+                 (type_count * sizeof (mach_port_type_t)));
+}
+
+
+void
+darwin_debug_port_info (task_t task, mach_port_t port)
+{
+  kern_return_t kret;
+  mach_port_status_t status;
+  mach_msg_type_number_t len = sizeof (status);
+
+  kret = mach_port_get_attributes
+    (task, port, MACH_PORT_RECEIVE_STATUS, (mach_port_info_t)&status, &len);
+  MACH_CHECK_ERROR (kret);
+
+  printf_unfiltered (_("Port 0x%lx in task 0x%lx:\n"), (unsigned long) port,
+                     (unsigned long) task);
+  printf_unfiltered (_("  port set: 0x%x\n"), status.mps_pset);
+  printf_unfiltered (_("     seqno: 0x%x\n"), status.mps_seqno);
+  printf_unfiltered (_("   mscount: 0x%x\n"), status.mps_mscount);
+  printf_unfiltered (_("    qlimit: 0x%x\n"), status.mps_qlimit);
+  printf_unfiltered (_("  msgcount: 0x%x\n"), status.mps_msgcount);
+  printf_unfiltered (_("  sorights: 0x%x\n"), status.mps_sorights);
+  printf_unfiltered (_("   srights: 0x%x\n"), status.mps_srights);
+  printf_unfiltered (_(" pdrequest: 0x%x\n"), status.mps_pdrequest);
+  printf_unfiltered (_(" nsrequest: 0x%x\n"), status.mps_nsrequest);
+  printf_unfiltered (_("     flags: 0x%x\n"), status.mps_flags);
+}
+
+static void
+info_mach_port_command (char *args, int from_tty)
+{
+  task_t task;
+  mach_port_t port;
+
+  CHECK_ARGS (_("Task and port"), args);
+  sscanf (args, "0x%x 0x%x", &task, &port);
+
+  darwin_debug_port_info (task, port);
+}
+
+static void
+info_mach_threads_command (char *args, int from_tty)
+{
+  thread_array_t threads;
+  unsigned int thread_count;
+  kern_return_t result;
+  task_t task;
+  int i;
+
+  task = get_task_from_args (args);
+  if (task == TASK_NULL)
+    return;
+
+  result = task_threads (task, &threads, &thread_count);
+  MACH_CHECK_ERROR (result);
+
+  printf_unfiltered (_("Threads in task %#x:\n"), task);
+  for (i = 0; i < thread_count; ++i)
+    {
+      printf_unfiltered (_("    %#x\n"), threads[i]);
+      mach_port_deallocate (task_self (), threads[i]);
+    }
+
+  vm_deallocate (task_self (), (vm_address_t) threads,
+                 (thread_count * sizeof (thread_t)));
+}
+
+static void
+info_mach_thread_command (char *args, int from_tty)
+{
+  union
+  {
+    struct thread_basic_info basic;
+  } thread_info_data;
+
+  thread_t thread;
+  kern_return_t result;
+  unsigned int info_count;
+
+  CHECK_ARGS (_("Thread"), args);
+  sscanf (args, "0x%x", &thread);
+
+  printf_unfiltered (_("THREAD_BASIC_INFO\n"));
+  info_count = THREAD_BASIC_INFO_COUNT;
+  result = thread_info (thread,
+			THREAD_BASIC_INFO,
+			(thread_info_t) & thread_info_data.basic,
+			&info_count);
+  MACH_CHECK_ERROR (result);
+
+#if 0
+  PRINT_FIELD (&thread_info_data.basic, user_time);
+  PRINT_FIELD (&thread_info_data.basic, system_time);
+#endif
+  PRINT_FIELD (&thread_info_data.basic, cpu_usage);
+  PRINT_FIELD (&thread_info_data.basic, run_state);
+  PRINT_FIELD (&thread_info_data.basic, flags);
+  PRINT_FIELD (&thread_info_data.basic, suspend_count);
+  PRINT_FIELD (&thread_info_data.basic, sleep_time);
+}
+
+static const char *
+unparse_protection (vm_prot_t p)
+{
+  switch (p)
+    {
+    case VM_PROT_NONE:
+      return "---";
+    case VM_PROT_READ:
+      return "r--";
+    case VM_PROT_WRITE:
+      return "-w-";
+    case VM_PROT_READ | VM_PROT_WRITE:
+      return "rw-";
+    case VM_PROT_EXECUTE:
+      return "--x";
+    case VM_PROT_EXECUTE | VM_PROT_READ:
+      return "r-x";
+    case VM_PROT_EXECUTE | VM_PROT_WRITE:
+      return "-wx";
+    case VM_PROT_EXECUTE | VM_PROT_WRITE | VM_PROT_READ:
+      return "rwx";
+    default:
+      return "???";
+    }
+}
+
+static const char *
+unparse_inheritance (vm_inherit_t i)
+{
+  switch (i)
+    {
+    case VM_INHERIT_SHARE:
+      return _("share");
+    case VM_INHERIT_COPY:
+      return _("copy ");
+    case VM_INHERIT_NONE:
+      return _("none ");
+    default:
+      return _("???  ");
+    }
+}
+
+static const char *
+unparse_share_mode (unsigned char p)
+{
+  switch (p)
+    {
+    case SM_COW:
+      return _("cow");
+    case SM_PRIVATE:
+      return _("private");
+    case SM_EMPTY:
+      return _("empty");
+    case SM_SHARED:
+      return _("shared");
+    case SM_TRUESHARED:
+      return _("true-shrd");
+    case SM_PRIVATE_ALIASED:
+      return _("prv-alias");
+    case SM_SHARED_ALIASED:
+      return _("shr-alias");
+    default:
+      return _("???");
+    }
+}
+
+static const char *
+unparse_user_tag (unsigned int tag)
+{
+  switch (tag)
+    {
+    case 0:
+      return _("default");
+    case VM_MEMORY_MALLOC:
+      return _("malloc");
+    case VM_MEMORY_MALLOC_SMALL:
+      return _("malloc_small");
+    case VM_MEMORY_MALLOC_LARGE:
+      return _("malloc_large");
+    case VM_MEMORY_MALLOC_HUGE:
+      return _("malloc_huge");
+    case VM_MEMORY_SBRK:
+      return _("sbrk");
+    case VM_MEMORY_REALLOC:
+      return _("realloc");
+    case VM_MEMORY_MALLOC_TINY:
+      return _("malloc_tiny");
+    case VM_MEMORY_ANALYSIS_TOOL:
+      return _("analysis_tool");
+    case VM_MEMORY_MACH_MSG:
+      return _("mach_msg");
+    case VM_MEMORY_IOKIT:
+      return _("iokit");
+    case VM_MEMORY_STACK:
+      return _("stack");
+    case VM_MEMORY_GUARD:
+      return _("guard");
+    case VM_MEMORY_SHARED_PMAP:
+      return _("shared_pmap");
+    case VM_MEMORY_DYLIB:
+      return _("dylib");
+    case VM_MEMORY_APPKIT:
+      return _("appkit");
+    case VM_MEMORY_FOUNDATION:
+      return _("foundation");
+    default:
+      return NULL;
+    }
+}
+
+static void
+darwin_debug_regions (task_t task, mach_vm_address_t address, int max)
+{
+  kern_return_t kret;
+  vm_region_basic_info_data_64_t info, prev_info;
+  mach_vm_address_t prev_address;
+  mach_vm_size_t size, prev_size;
+
+  mach_port_t object_name;
+  mach_msg_type_number_t count;
+
+  int nsubregions = 0;
+  int num_printed = 0;
+
+  count = VM_REGION_BASIC_INFO_COUNT_64;
+  kret = mach_vm_region (task, &address, &size, VM_REGION_BASIC_INFO_64,
+			 (vm_region_info_t) &info, &count, &object_name);
+  if (kret != KERN_SUCCESS)
+    {
+      printf_filtered (_("No memory regions."));
+      return;
+    }
+  memcpy (&prev_info, &info, sizeof (vm_region_basic_info_data_64_t));
+  prev_address = address;
+  prev_size = size;
+  nsubregions = 1;
+
+  for (;;)
+    {
+      int print = 0;
+      int done = 0;
+
+      address = prev_address + prev_size;
+
+      /* Check to see if address space has wrapped around. */
+      if (address == 0)
+        print = done = 1;
+
+      if (!done)
+        {
+          count = VM_REGION_BASIC_INFO_COUNT_64;
+          kret =
+            mach_vm_region (task, &address, &size, VM_REGION_BASIC_INFO_64,
+                 	      (vm_region_info_t) &info, &count, &object_name);
+          if (kret != KERN_SUCCESS)
+            {
+              size = 0;
+              print = done = 1;
+            }
+        }
+
+      if (address != prev_address + prev_size)
+        print = 1;
+
+      if ((info.protection != prev_info.protection)
+          || (info.max_protection != prev_info.max_protection)
+          || (info.inheritance != prev_info.inheritance)
+          || (info.shared != prev_info.reserved)
+          || (info.reserved != prev_info.reserved))
+        print = 1;
+
+      if (print)
+        {
+          printf_filtered (_("%s-%s %s/%s  %s %s %s"),
+                           paddr(prev_address),
+                           paddr(prev_address + prev_size),
+                           unparse_protection (prev_info.protection),
+                           unparse_protection (prev_info.max_protection),
+                           unparse_inheritance (prev_info.inheritance),
+                           prev_info.shared ? _("shrd") : _("priv"),
+                           prev_info.reserved ? _("reserved") : _("not-rsvd"));
+
+          if (nsubregions > 1)
+            printf_filtered (_(" (%d sub-rgn)"), nsubregions);
+
+          printf_filtered (_("\n"));
+
+          prev_address = address;
+          prev_size = size;
+          memcpy (&prev_info, &info, sizeof (vm_region_basic_info_data_64_t));
+          nsubregions = 1;
+
+          num_printed++;
+        }
+      else
+        {
+          prev_size += size;
+          nsubregions++;
+        }
+
+      if ((max > 0) && (num_printed >= max))
+        done = 1;
+
+      if (done)
+        break;
+    }
+}
+
+static void
+darwin_debug_regions_recurse (task_t task)
+{
+  mach_vm_address_t r_addr;
+  mach_vm_address_t r_start;
+  mach_vm_size_t r_size;
+  natural_t r_depth;
+  mach_msg_type_number_t r_info_size;
+  vm_region_submap_short_info_data_64_t r_info;
+  kern_return_t kret;
+  int ret;
+
+  r_start = 0;
+  r_depth = 0;
+  while (1)
+    {
+      const char *tag;
+
+      r_info_size = VM_REGION_SUBMAP_SHORT_INFO_COUNT_64;
+      r_size = -1;
+      kret = mach_vm_region_recurse (task, &r_start, &r_size, &r_depth,
+				     (vm_region_recurse_info_t) &r_info,
+				     &r_info_size);
+      if (kret != KERN_SUCCESS)
+	break;
+      printf_filtered (_("%s-%s %s/%s  %-5s %-10s %2d %s"),
+		       paddr(r_start),
+		       paddr(r_start + r_size),
+		       unparse_protection (r_info.protection),
+		       unparse_protection (r_info.max_protection),
+		       unparse_inheritance (r_info.inheritance),
+		       unparse_share_mode (r_info.share_mode),
+		       r_depth,
+		       r_info.is_submap ? _("sm ") : _("obj"));
+      tag = unparse_user_tag (r_info.user_tag);
+      if (tag)
+	printf_unfiltered (_(" %s\n"), tag);
+      else
+	printf_unfiltered (_(" %u\n"), r_info.user_tag);
+      if (r_info.is_submap)
+	r_depth++;
+      else
+	r_start += r_size;
+    }
+}
+
+
+static void
+darwin_debug_region (task_t task, mach_vm_address_t address)
+{
+  darwin_debug_regions (task, address, 1);
+}
+
+static void
+info_mach_regions_command (char *args, int from_tty)
+{
+  task_t task;
+
+  task = get_task_from_args (args);
+  if (task == TASK_NULL)
+    return;
+  
+  darwin_debug_regions (task, 0, -1);
+}
+
+static void
+info_mach_regions_recurse_command (char *args, int from_tty)
+{
+  task_t task;
+
+  task = get_task_from_args (args);
+  if (task == TASK_NULL)
+    return;
+  
+  darwin_debug_regions_recurse (task);
+}
+
+static void
+info_mach_region_command (char *exp, int from_tty)
+{
+  struct expression *expr;
+  struct value *val;
+  mach_vm_address_t address;
+
+  expr = parse_expression (exp);
+  val = evaluate_expression (expr);
+  if (TYPE_CODE (value_type (val)) == TYPE_CODE_REF)
+    {
+      val = value_ind (val);
+    }
+  /* In rvalue contexts, such as this, functions are coerced into
+     pointers to functions. */
+  if (TYPE_CODE (value_type (val)) == TYPE_CODE_FUNC
+      && VALUE_LVAL (val) == lval_memory)
+    {
+      address = VALUE_ADDRESS (val);
+    }
+  else
+    {
+      address = value_as_address (val);
+    }
+
+  if ((!darwin_inf) || (darwin_inf->task == TASK_NULL))
+    error (_("Inferior not available"));
+
+  darwin_debug_region (darwin_inf->task, address);
+}
+
+static void
+disp_exception (const darwin_exception_info *info)
+{
+  int i;
+
+  printf_filtered (_("%d exceptions:\n"), info->count);
+  for (i = 0; i < info->count; i++)
+    {
+      exception_mask_t mask = info->masks[i];
+
+      printf_filtered (_("port 0x%04x, behavior: "), info->ports[i]);
+      switch (info->behaviors[i])
+	{
+	case EXCEPTION_DEFAULT:
+	  printf_unfiltered (_("default"));
+	  break;
+	case EXCEPTION_STATE:
+	  printf_unfiltered (_("state"));
+	  break;
+	case EXCEPTION_STATE_IDENTITY:
+	  printf_unfiltered (_("state-identity"));
+	  break;
+	default:
+	  printf_unfiltered (_("0x%x"), info->behaviors[i]);
+	}
+      printf_unfiltered (_(", masks:"));
+      if (mask & EXC_MASK_BAD_ACCESS)
+	printf_unfiltered (_(" BAD_ACCESS"));
+      if (mask & EXC_MASK_BAD_INSTRUCTION)
+	printf_unfiltered (_(" BAD_INSTRUCTION"));
+      if (mask & EXC_MASK_ARITHMETIC)
+	printf_unfiltered (_(" ARITHMETIC"));
+      if (mask & EXC_MASK_EMULATION)
+	printf_unfiltered (_(" EMULATION"));
+      if (mask & EXC_MASK_SOFTWARE)
+	printf_unfiltered (_(" SOFTWARE"));
+      if (mask & EXC_MASK_BREAKPOINT)
+	printf_unfiltered (_(" BREAKPOINT"));
+      if (mask & EXC_MASK_SYSCALL)
+	printf_unfiltered (_(" SYSCALL"));
+      if (mask & EXC_MASK_MACH_SYSCALL)
+	printf_unfiltered (_(" MACH_SYSCALL"));
+      if (mask & EXC_MASK_RPC_ALERT)
+	printf_unfiltered (_(" RPC_ALERT"));
+      if (mask & EXC_MASK_CRASH)
+	printf_unfiltered (_(" CRASH"));
+      printf_unfiltered (_("\n"));
+    }
+}
+
+static void
+info_mach_exceptions_command (char *args, int from_tty)
+{
+  int i;
+  task_t task;
+  kern_return_t kret;
+  darwin_exception_info info;
+
+  info.count = sizeof (info.ports) / sizeof (info.ports[0]);
+
+  if (args != NULL)
+    {
+      if (strcmp (args, "saved") == 0)
+	{
+	  if (darwin_inf->task == TASK_NULL)
+	    error (_("No inferior running\n"));
+	  disp_exception (&darwin_inf->exception_info);
+	  return;
+	}
+      else if (strcmp (args, "host") == 0)
+	{
+	  /* FIXME: This need a the privilegied host port!  */
+	  kret = host_get_exception_ports
+	    (darwin_host_self, EXC_MASK_ALL, info.masks,
+	     &info.count, info.ports, info.behaviors, info.flavors);
+	  MACH_CHECK_ERROR (kret);
+	  disp_exception (&info);
+	}
+      else
+	error (_("Parameter is saved, host or none"));
+    }
+  else
+    {
+      if (darwin_inf->task == TASK_NULL)
+	error (_("No inferior running\n"));
+      
+      kret = task_get_exception_ports
+	(darwin_inf->task, EXC_MASK_ALL, info.masks,
+	 &info.count, info.ports, info.behaviors, info.flavors);
+      MACH_CHECK_ERROR (kret);
+      disp_exception (&info);
+    }
+}
+
+static void
+darwin_list_gdb_ports (const char *msg)
+{
+  mach_port_name_array_t names;
+  mach_port_type_array_t types;
+  unsigned int name_count, type_count;
+  kern_return_t result;
+  int i;
+
+  result = mach_port_names (mach_task_self (),
+			    &names, &name_count, &types, &type_count);
+  MACH_CHECK_ERROR (result);
+
+  gdb_assert (name_count == type_count);
+
+  printf_unfiltered (_("Ports for %s:"), msg);
+  for (i = 0; i < name_count; ++i)
+    printf_unfiltered (_(" 0x%04x"), names[i]);
+  printf_unfiltered (_("\n"));
+
+  vm_deallocate (mach_task_self (), (vm_address_t) names,
+                 (name_count * sizeof (mach_port_t)));
+  vm_deallocate (mach_task_self (), (vm_address_t) types,
+                 (type_count * sizeof (mach_port_type_t)));
+}
+
+void
+_initialize_darwin_info_commands (void)
+{
+  add_info ("mach-tasks", info_mach_tasks_command,
+            _("Get list of tasks in system."));
+  add_info ("mach-ports", info_mach_ports_command,
+            _("Get list of ports in a task."));
+  add_info ("mach-port", info_mach_port_command,
+            _("Get info on a specific port."));
+  add_info ("mach-task", info_mach_task_command,
+            _("Get info on a specific task."));
+  add_info ("mach-threads", info_mach_threads_command,
+            _("Get list of threads in a task."));
+  add_info ("mach-thread", info_mach_thread_command,
+            _("Get info on a specific thread."));
+
+  add_info ("mach-regions", info_mach_regions_command,
+            _("Get information on all mach region for the task."));
+  add_info ("mach-regions-rec", info_mach_regions_recurse_command,
+            _("Get information on all mach sub region for the task."));
+  add_info ("mach-region", info_mach_region_command,
+            _("Get information on mach region at given address."));
+
+  add_info ("mach-exceptions", info_mach_exceptions_command,
+            _("Disp mach exceptions."));
+}
diff --git a/gdb/darwin-nat.c b/gdb/darwin-nat.c
new file mode 100644
index 00000000000..de9c7153e1f
--- /dev/null
+++ b/gdb/darwin-nat.c
@@ -0,0 +1,1307 @@
+/* Darwin support for GDB, the GNU debugger.
+   Copyright (C) 2008 Free Software Foundation, Inc.
+
+   Contributed by AdaCore.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "defs.h"
+#include "top.h"
+#include "inferior.h"
+#include "target.h"
+#include "symfile.h"
+#include "symtab.h"
+#include "objfiles.h"
+#include "gdb.h"
+#include "gdbcmd.h"
+#include "gdbcore.h"
+#include "gdbthread.h"
+#include "regcache.h"
+#include "event-top.h"
+#include "inf-loop.h"
+#include "gdb_stat.h"
+#include "exceptions.h"
+#include "inf-child.h"
+#include "value.h"
+#include "arch-utils.h"
+#include "bfd.h"
+
+#include <sys/ptrace.h>
+#include <sys/signal.h>
+#include <machine/setjmp.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <signal.h>
+#include <string.h>
+#include <ctype.h>
+#include <sys/param.h>
+#include <sys/sysctl.h>
+#include <sys/proc.h>
+
+#include <mach/mach_error.h>
+#include <mach/mach_vm.h>
+#include <mach/mach_init.h>
+#include <mach/vm_map.h>
+#include <mach/task.h>
+#include <mach/mach_port.h>
+#include <mach/thread_act.h>
+#include <mach/port.h>
+
+#include "darwin-nat.h"
+
+/* Quick overview.
+   Darwin kernel is Mach + BSD derived kernel.  Note that they share the
+   same memory space and are linked together (ie there is no micro-kernel).
+
+   Although ptrace(2) is available on Darwin, it is not complete.  We have
+   to use Mach calls to read and write memory and to modify registers.  We
+   also use Mach to get inferior faults.  As we cannot use select(2) or
+   signals with Mach port (the Mach communication channel), signals are
+   reported to gdb as an exception.  Furthermore we detect death of the
+   inferior through a Mach notification message.  This way we only wait
+   on Mach ports.
+
+   Some Mach documentation is available for Apple xnu source package or
+   from the web.  */
+
+
+#define PTRACE(CMD, PID, ADDR, SIG) \
+ darwin_ptrace(#CMD, CMD, (PID), (ADDR), (SIG))
+
+extern boolean_t exc_server (mach_msg_header_t *in, mach_msg_header_t *out);
+
+static void darwin_stop (ptid_t);
+
+static void darwin_resume (ptid_t ptid, int step,
+			   enum target_signal signal);
+
+static ptid_t darwin_wait (ptid_t ptid, struct target_waitstatus *status);
+
+static void darwin_mourn_inferior (struct target_ops *ops);
+
+static int darwin_lookup_task (char *args, task_t * ptask, int *ppid);
+
+static void darwin_kill_inferior (void);
+
+static void darwin_ptrace_me (void);
+
+static void darwin_ptrace_him (int pid);
+
+static void darwin_create_inferior (struct target_ops *ops, char *exec_file,
+				    char *allargs, char **env, int from_tty);
+
+static void darwin_files_info (struct target_ops *ops);
+
+static char *darwin_pid_to_str (ptid_t tpid);
+
+static int darwin_thread_alive (ptid_t tpid);
+
+/* Current inferior.  */
+darwin_inferior *darwin_inf = NULL;
+
+/* Target operations for Darwin.  */
+static struct target_ops *darwin_ops;
+
+/* Task identifier of gdb.  */
+static task_t gdb_task;
+
+/* A copy of mach_host_self ().  */
+mach_port_t darwin_host_self;
+
+/* Exception port.  */
+mach_port_t darwin_ex_port;
+
+/* Notification port.  */
+mach_port_t darwin_not_port;
+
+/* Port set.  */
+mach_port_t darwin_port_set;
+
+/* Page size. */
+static vm_size_t mach_page_size;
+
+/* If Set, catch all mach exceptions (before they are converted to signals
+   by the kernel).  */
+static int enable_mach_exceptions;
+
+#define PAGE_TRUNC(x) ((x) & ~(mach_page_size - 1))
+#define PAGE_ROUND(x) PAGE_TRUNC((x) + mach_page_size - 1)
+
+/* Buffer containing received message and to be sent message.  */
+static union
+{
+  mach_msg_header_t hdr;
+  char data[1024];
+} msgin, msgout;
+
+/* Current message state.
+   If the kernel has sent a message it expects a reply and the inferior
+   can't be killed before.  */
+static enum msg_state { NO_MESSAGE, GOT_MESSAGE, REPLY_SENT } msg_state;
+
+/* Unmarshalled received message.  */
+static struct exc_msg
+{
+  /* Receive port.  */
+  mach_port_t port;
+
+  /* Thread and task taking the exception.  */
+  mach_port_t thread_port;
+  mach_port_t task_port;
+
+  /* Type of the exception.  */
+  exception_type_t ex_type;
+
+  /* Machine dependent details.  */
+  mach_msg_type_number_t data_count;
+  integer_t ex_data[4];
+} exc_msg;
+
+
+/* This controls output of inferior debugging.
+   1 = basic exception handling
+   2 = task management
+   3 = thread management
+   4 = pending_event_handler
+   6 = most chatty level.  */
+
+static int darwin_debug_flag = 0;
+
+static void
+inferior_debug (int level, const char *fmt, ...)
+{
+  va_list ap;
+
+  if (darwin_debug_flag < level)
+    return;
+
+  va_start (ap, fmt);
+  printf_unfiltered (_("[%d inferior]: "), getpid ());
+  vprintf_unfiltered (fmt, ap);
+  va_end (ap);
+}
+
+void
+mach_check_error (kern_return_t ret, const char *file,
+                  unsigned int line, const char *func)
+{
+  if (ret == KERN_SUCCESS)
+    return;
+  if (func == NULL)
+    func = _("[UNKNOWN]");
+  
+  error (_("error on line %u of \"%s\" in function \"%s\": %s (0x%lx)\n"),
+         line, file, func, mach_error_string (ret), (unsigned long) ret);
+}
+
+static const char *
+unparse_exception_type (unsigned int i)
+{
+  static char unknown_exception_buf[32];
+
+  switch (i)
+    {
+    case EXC_BAD_ACCESS:
+      return "EXC_BAD_ACCESS";
+    case EXC_BAD_INSTRUCTION:
+      return "EXC_BAD_INSTRUCTION";
+    case EXC_ARITHMETIC:
+      return "EXC_ARITHMETIC";
+    case EXC_EMULATION:
+      return "EXC_EMULATION";
+    case EXC_SOFTWARE:
+      return "EXC_SOFTWARE";
+    case EXC_BREAKPOINT:
+      return "EXC_BREAKPOINT";
+    case EXC_SYSCALL:
+      return "EXC_SYSCALL";
+    case EXC_MACH_SYSCALL:
+      return "EXC_MACH_SYSCALL";
+    case EXC_RPC_ALERT:
+      return "EXC_RPC_ALERT";
+    case EXC_CRASH:
+      return "EXC_CRASH";
+    default:
+      snprintf (unknown_exception_buf, 32, _("unknown (%d)"), i);
+      return unknown_exception_buf;
+    }
+}
+
+static int
+darwin_ptrace (const char *name,
+	       int request, int pid, PTRACE_TYPE_ARG3 arg3, int arg4)
+{
+  int ret;
+
+  ret = ptrace (request, pid, (caddr_t) arg3, arg4);
+
+  inferior_debug (2, _("ptrace (%s, %d, 0x%x, %d): %d (%s)\n"),
+                  name, pid, arg3, arg4, ret,
+                  (ret != 0) ? strerror (errno) : _("no error"));
+  return ret;
+}
+
+static int
+cmp_thread_t (const void *l, const void *r)
+{
+  thread_t lt = *(const thread_t *)l;
+  thread_t lr = *(const thread_t *)r;
+  return (int)(lr - lt);
+}
+
+static void
+darwin_check_new_threads (darwin_inferior *inf)
+{
+  kern_return_t kret;
+  unsigned int i;
+  thread_array_t thread_list;
+  unsigned int new_nbr;
+  unsigned int old_nbr;
+  unsigned int new_ix, old_ix;
+  VEC (thread_t) *thread_vec;
+
+  /* Get list of threads.  */
+  kret = task_threads (inf->task, &thread_list, &new_nbr);
+  MACH_CHECK_ERROR (kret);
+  if (kret != KERN_SUCCESS)
+    return;
+
+  if (new_nbr > 1)
+    qsort (thread_list, new_nbr, sizeof (thread_t), cmp_thread_t);
+
+  thread_vec = VEC_alloc (thread_t, new_nbr);
+
+  if (inf->threads)
+    old_nbr = VEC_length (thread_t, inf->threads);
+  else
+    old_nbr = 0;
+
+  for (new_ix = 0, old_ix = 0; new_ix < new_nbr || old_ix < old_nbr;)
+    {
+      thread_t new_id = (new_ix < new_nbr) ?
+	thread_list[new_ix] : THREAD_NULL;
+      thread_t old_id = (old_ix < old_nbr) ?
+	VEC_index (thread_t, inf->threads, old_ix) : THREAD_NULL;
+
+      if (old_id == new_id)
+	{
+	  /* Thread still exist.  */
+	  VEC_safe_push (thread_t, thread_vec, old_id);
+	  new_ix++;
+	  old_ix++;
+
+	  kret = mach_port_deallocate (gdb_task, old_id);
+	  MACH_CHECK_ERROR (kret);
+	  continue;
+	}
+      if (new_id < old_id || old_ix == old_nbr)
+	{
+	  /* A thread was created.  */
+	  struct thread_info *tp;
+
+	  tp = add_thread (ptid_build (inf->pid, 0, new_id));
+	  VEC_safe_push (thread_t, thread_vec, new_id);
+	  new_ix++;
+	  continue;
+	}
+      if (new_id > old_id || new_ix == new_nbr)
+	{
+	  /* A thread was removed.  */
+	  delete_thread (ptid_build (inf->pid, 0, old_id));
+	  kret = mach_port_deallocate (gdb_task, old_id);
+	  MACH_CHECK_ERROR (kret);
+	  old_ix++;
+	}
+    }
+
+  if (inf->threads)
+    VEC_free (thread_t, inf->threads);
+  inf->threads = thread_vec;
+
+  kret = vm_deallocate (gdb_task, (vm_address_t) thread_list,
+			new_nbr * sizeof (int));
+  MACH_CHECK_ERROR (kret);
+}
+
+static void
+darwin_stop (ptid_t t)
+{
+  int ret;
+
+  ret = kill (ptid_get_pid (inferior_ptid), SIGINT);
+}
+
+static void
+darwin_resume (ptid_t ptid, int step, enum target_signal signal)
+{
+  struct target_waitstatus status;
+  int pid;
+  thread_t thread;
+  kern_return_t kret;
+  int res;
+
+  /* minus_one_ptid is RESUME_ALL.  */
+  if (ptid_equal (ptid, minus_one_ptid))
+    ptid = inferior_ptid;
+
+  pid = ptid_get_pid (ptid);
+  thread = ptid_get_tid (ptid);
+
+  inferior_debug
+    (2, _("darwin_resume: state=%d, thread=0x%x, step=%d signal=%d\n"),
+     msg_state, thread, step, signal);
+
+  switch (msg_state)
+    {
+    case GOT_MESSAGE:
+      switch (exc_msg.ex_type)
+	{
+	case EXC_SOFTWARE:
+	  if (exc_msg.ex_data[0] == EXC_SOFT_SIGNAL)
+	    {
+	      int nsignal = target_signal_to_host (signal);
+	      res = PTRACE (PT_THUPDATE, pid,
+				   (void *)exc_msg.thread_port, nsignal);
+	      if (res < 0)
+		printf_unfiltered (_("ptrace THUP: res=%d\n"), res);
+	    }
+	  break;
+
+	default:
+	  break;
+	}
+	  
+      if (thread != 0)
+	{
+	  inferior_debug (2, _("darwin_set_sstep (thread=%x, enable=%d)\n"),
+			  thread, step);
+	  darwin_set_sstep (thread, step);
+	}
+
+      kret = mach_msg (&msgout.hdr, MACH_SEND_MSG | MACH_SEND_INTERRUPT,
+		       msgout.hdr.msgh_size, 0,
+		       MACH_PORT_NULL, MACH_MSG_TIMEOUT_NONE,
+		       MACH_PORT_NULL);
+      if (kret != 0)
+	printf_unfiltered (_("mach_msg (reply) ret=%d\n"), kret);
+
+      msg_state = REPLY_SENT;
+      break;
+
+    case NO_MESSAGE:
+      if (step)
+	res = PTRACE (PT_STEP, pid, (caddr_t)1, 0);
+      else
+	res = PTRACE (PT_CONTINUE, pid, (caddr_t)1, 0);
+      break;
+
+    default:
+      gdb_assert (0);
+    }
+}
+
+kern_return_t
+catch_exception_raise_state
+  (mach_port_t port,
+   exception_type_t exception_type, mach_exception_data_t exception_data,
+   mach_msg_type_number_t data_count, thread_state_flavor_t * state_flavor,
+   thread_state_t in_state, mach_msg_type_number_t in_state_count,
+   thread_state_t out_state, mach_msg_type_number_t out_state_count)
+{
+  return KERN_FAILURE;
+}
+
+kern_return_t
+catch_exception_raise_state_identity
+  (mach_port_t port, mach_port_t thread_port, mach_port_t task_port,
+   exception_type_t exception_type, mach_exception_data_t exception_data,
+   mach_msg_type_number_t data_count, thread_state_flavor_t * state_flavor,
+   thread_state_t in_state, mach_msg_type_number_t in_state_count,
+   thread_state_t out_state, mach_msg_type_number_t out_state_count)
+{
+  kern_return_t kret;
+
+  kret = mach_port_deallocate (mach_task_self (), task_port);
+  MACH_CHECK_ERROR (kret);
+  kret = mach_port_deallocate (mach_task_self (), thread_port);
+  MACH_CHECK_ERROR (kret);
+
+  return KERN_FAILURE;
+}
+
+kern_return_t
+catch_exception_raise (mach_port_t port,
+		       mach_port_t thread_port,
+		       mach_port_t task_port,
+		       exception_type_t exception_type,
+		       exception_data_t exception_data,
+		       mach_msg_type_number_t data_count)
+{
+  kern_return_t kret;
+  int i;
+  int res;
+
+  /* We got new rights to the task.  Get rid of it.  */
+  kret = mach_port_deallocate (mach_task_self (), task_port);
+  MACH_CHECK_ERROR (kret);
+
+  inferior_debug
+    (7, _("catch_exception_raise: exception_type=%d, data_count=%d\n"),
+     exception_type, data_count);
+  if (darwin_debug_flag > 7)
+    {
+      for (i = 0; i < data_count; i++)
+	printf_unfiltered (" %08x", exception_data[i]);
+      printf_unfiltered ("\n");
+    }
+
+  /* Save the message.
+     FIXME: this should be in a per-thread variable.  */
+  exc_msg.port = port;
+  exc_msg.thread_port = thread_port;
+  exc_msg.task_port = task_port;
+  exc_msg.ex_type = exception_type;
+  exc_msg.data_count = data_count;
+  for (i = 0; i < data_count && i < 4; i++)
+    exc_msg.ex_data[i] = exception_data[i];
+
+  return KERN_SUCCESS;
+}
+
+static ptid_t
+darwin_wait (ptid_t ptid, struct target_waitstatus *status)
+{
+  kern_return_t kret;
+  mach_msg_header_t *hdr = &msgin.hdr;
+  pid_t pid = ptid_get_pid (inferior_ptid); /* FIXME.  */
+
+  gdb_assert (msg_state != GOT_MESSAGE);
+
+  inferior_debug (6, _("darwin_wait: waiting for a message\n"));
+
+  /* Wait for a message.  */
+  kret = mach_msg (&msgin.hdr, MACH_RCV_MSG | MACH_RCV_INTERRUPT, 0,
+		   sizeof (msgin.data), darwin_port_set, 0, MACH_PORT_NULL);
+
+  if (kret == MACH_RCV_INTERRUPTED)
+    {
+      status->kind = TARGET_WAITKIND_IGNORE;
+      return minus_one_ptid;
+    }
+
+  if (kret != MACH_MSG_SUCCESS)
+    {
+      inferior_debug (1, _("mach_msg: ret=%x\n"), kret);
+      status->kind = TARGET_WAITKIND_SPURIOUS;
+      return minus_one_ptid;
+    }
+
+  /* Debug: display message.  */
+  if (darwin_debug_flag > 10)
+   {
+     const unsigned long *buf = (unsigned long *) hdr;
+     unsigned int i;
+     
+     printf_unfiltered (_(" bits: 0x%x"), hdr->msgh_bits);
+     printf_unfiltered (_(", size: 0x%x"), hdr->msgh_size);
+     printf_unfiltered (_(", remote-port: 0x%x"), hdr->msgh_remote_port);
+     printf_unfiltered (_(", local-port: 0x%x"), hdr->msgh_local_port);
+     printf_unfiltered (_(", reserved: 0x%x"), hdr->msgh_reserved);
+     printf_unfiltered (_(", id: 0x%x\n"), hdr->msgh_id);
+
+     if (darwin_debug_flag > 11)
+	{
+	  printf_unfiltered (_("  data:"));
+	  for (i = 0; i < hdr->msgh_size; i++)
+	    printf_unfiltered (" %08lx", buf[i]);
+	  printf_unfiltered (_("\n"));
+	}
+   }
+
+  /* Exception message.  */
+  if (hdr->msgh_local_port == darwin_ex_port)
+    {
+      /* Handle it via the exception server.  */
+      if (!exc_server (&msgin.hdr, &msgout.hdr))
+	{
+	  printf_unfiltered (_("exc_server: unknown message (id=%x)\n"),
+			     hdr->msgh_id);
+	  status->kind = TARGET_WAITKIND_SPURIOUS;
+	  return minus_one_ptid;
+	}
+
+      status->kind = TARGET_WAITKIND_STOPPED;
+
+      inferior_debug (2, _("darwin_wait: thread=%x, got %s\n"),
+		      exc_msg.thread_port, 
+		      unparse_exception_type (exc_msg.ex_type));
+  
+      switch (exc_msg.ex_type)
+	{
+	case EXC_BAD_ACCESS:
+	  status->value.sig = TARGET_EXC_BAD_ACCESS;
+	  break;
+	case EXC_BAD_INSTRUCTION:
+	  status->value.sig = TARGET_EXC_BAD_INSTRUCTION;
+	  break;
+	case EXC_ARITHMETIC:
+	  status->value.sig = TARGET_EXC_ARITHMETIC;
+	  break;
+	case EXC_EMULATION:
+	  status->value.sig = TARGET_EXC_EMULATION;
+	  break;
+	case EXC_SOFTWARE:
+	  if (exc_msg.ex_data[0] == EXC_SOFT_SIGNAL)
+	    {
+	      status->value.sig = target_signal_from_host (exc_msg.ex_data[1]);
+	      inferior_debug (2, _("  (signal %d: %s)\n"),
+			      exc_msg.ex_data[1],
+			      target_signal_to_name (status->value.sig));
+	    }
+	  else
+            status->value.sig = TARGET_EXC_SOFTWARE;
+	  break;
+	case EXC_BREAKPOINT:
+	  /* Many internal GDB routines expect breakpoints to be reported
+	     as TARGET_SIGNAL_TRAP, and will report TARGET_EXC_BREAKPOINT
+	     as a spurious signal. */
+	  status->value.sig = TARGET_SIGNAL_TRAP;
+	  break;
+	default:
+	  status->value.sig = TARGET_SIGNAL_UNKNOWN;
+	  break;
+	}
+
+      msg_state = GOT_MESSAGE;
+
+      return ptid_build (pid, 0, exc_msg.thread_port);
+    }
+  else if (hdr->msgh_local_port == darwin_not_port)
+    {
+      pid_t res;
+      int wstatus;
+
+      /* FIXME: translate task port to pid.  */
+      res = wait4 (pid, &wstatus, 0, NULL);
+      if (res != pid)
+	{
+	  printf_unfiltered (_("wait4: res=%x\n"), res);
+	  wstatus = 0;
+	}
+      status->kind = TARGET_WAITKIND_EXITED;
+      status->value.integer = WEXITSTATUS (wstatus);
+
+      inferior_debug (2, _("darwin_wait: pid=%d exit, status=%x\n"),
+		      pid, wstatus);
+
+      msg_state = NO_MESSAGE;
+
+      return ptid;
+    }
+  else
+    {
+      printf_unfiltered (_("Bad local-port: %x\n"), hdr->msgh_local_port);
+      status->kind = TARGET_WAITKIND_SPURIOUS;
+      return minus_one_ptid;
+    }
+}
+
+static void
+darwin_mourn_inferior (struct target_ops *ops)
+{
+  struct inferior *inf = current_inferior ();
+  kern_return_t kret;
+  mach_port_t prev;
+  int i;
+
+  unpush_target (darwin_ops);
+
+  /* Deallocate threads.  */
+  if (darwin_inf->threads)
+    {
+      int k;
+      thread_t t;
+      for (k = 0; VEC_iterate (thread_t, darwin_inf->threads, k, t); k++)
+	{
+	  kret = mach_port_deallocate (gdb_task, t);
+	  MACH_CHECK_ERROR (kret);
+	}
+      VEC_free (thread_t, darwin_inf->threads);
+      darwin_inf->threads = NULL;
+    }
+
+  kret = mach_port_request_notification (gdb_task, darwin_inf->task,
+					 MACH_NOTIFY_DEAD_NAME, 0,
+					 darwin_inf->prev_not_port,
+					 MACH_MSG_TYPE_MAKE_SEND_ONCE,
+					 &prev);
+  /* This can fail if the task is dead.  */
+  if (kret == KERN_SUCCESS)
+    {
+      kret = mach_port_deallocate (gdb_task, prev);
+      MACH_CHECK_ERROR (kret);
+    }
+
+  /* Deallocate saved exception ports.  */
+  for (i = 0; i < darwin_inf->exception_info.count; i++)
+    {
+      kret = mach_port_deallocate
+	(gdb_task, darwin_inf->exception_info.ports[i]);
+      MACH_CHECK_ERROR (kret);
+    }
+  darwin_inf->exception_info.count = 0;
+
+  kret = mach_port_deallocate (gdb_task, darwin_inf->task);
+  MACH_CHECK_ERROR (kret);
+
+  darwin_inf->task = 0;
+  darwin_inf->pid = 0;
+
+  generic_mourn_inferior ();
+}
+
+static void
+darwin_stop_inferior (darwin_inferior *inf)
+{
+  struct target_waitstatus wstatus;
+  ptid_t ptid;
+  kern_return_t kret;
+  int status;
+  int res;
+
+  gdb_assert (inf != NULL);
+
+  kret = task_suspend (inf->task);
+  MACH_CHECK_ERROR (kret);
+
+  if (msg_state == GOT_MESSAGE)
+    darwin_resume (inferior_ptid, 0, 0);
+
+  res = kill (inf->pid, SIGSTOP);
+  if (res != 0)
+    warning (_("cannot kill: %s\n"), strerror (errno));
+
+  ptid = darwin_wait (inferior_ptid, &wstatus);
+  gdb_assert (wstatus.kind = TARGET_WAITKIND_STOPPED);
+}
+
+static void
+darwin_kill_inferior (void)
+{
+  struct target_waitstatus wstatus;
+  ptid_t ptid;
+  kern_return_t kret;
+  int status;
+  int res;
+
+  gdb_assert (darwin_inf != NULL);
+
+  if (ptid_equal (inferior_ptid, null_ptid))
+    return;
+
+  darwin_stop_inferior (darwin_inf);
+
+  res = PTRACE (PT_KILL, darwin_inf->pid, 0, 0);
+  gdb_assert (res == 0);
+
+  if (msg_state == GOT_MESSAGE)
+    {
+      exc_msg.ex_type = 0;
+      darwin_resume (inferior_ptid, 0, 0);
+    }
+
+  kret = task_resume (darwin_inf->task);
+  MACH_CHECK_ERROR (kret);
+
+  ptid = darwin_wait (inferior_ptid, &wstatus);
+
+  /* This double wait seems required...  */
+  res = waitpid (darwin_inf->pid, &status, 0);
+  gdb_assert (res == darwin_inf->pid);
+
+  msg_state = NO_MESSAGE;
+
+  target_mourn_inferior ();
+}
+
+/* The child must synchronize with gdb: gdb must set the exception port
+   before the child call PTRACE_SIGEXC.  We use a pipe to achieve this.
+   FIXME: is there a lighter way ?  */
+static int ptrace_fds[2];
+
+static void
+darwin_ptrace_me (void)
+{
+  int res;
+  char c;
+
+  /* Close write end point.  */
+  close (ptrace_fds[1]);
+
+  /* Wait until gdb is ready.  */
+  res = read (ptrace_fds[0], &c, 1);
+  gdb_assert (res == 0);
+  close (ptrace_fds[0]);
+
+  /* Get rid of privileges.  */
+  setegid (getgid ());
+
+  /* Set TRACEME.  */
+  PTRACE (PT_TRACE_ME, 0, 0, 0);
+
+  /* Redirect signals to exception port.  */
+  PTRACE (PT_SIGEXC, 0, 0, 0);
+}
+
+/* Dummy function to be sure fork_inferior uses fork(2) and not vfork(2).  */
+static void
+darwin_pre_ptrace (void)
+{
+  if (pipe (ptrace_fds) != 0)
+    {
+      ptrace_fds[0] = -1;
+      ptrace_fds[1] = -1;
+      error (_("unable to create a pipe: %s"), safe_strerror (errno));
+    }
+}
+
+static kern_return_t
+darwin_save_exception_ports (darwin_inferior *inf)
+{
+  kern_return_t kret;
+
+  inf->exception_info.count =
+    sizeof (inf->exception_info.ports) / sizeof (inf->exception_info.ports[0]);
+
+  kret = task_get_exception_ports
+    (inf->task, EXC_MASK_ALL, inf->exception_info.masks,
+     &inf->exception_info.count, inf->exception_info.ports,
+     inf->exception_info.behaviors, inf->exception_info.flavors);
+  return kret;
+}
+
+static kern_return_t
+darwin_restore_exception_ports (darwin_inferior *inf)
+{
+  int i;
+  kern_return_t kret;
+
+  for (i = 0; i < inf->exception_info.count; i++)
+    {
+      kret = task_set_exception_ports
+        (inf->task, inf->exception_info.masks[i], inf->exception_info.ports[i],
+	 inf->exception_info.behaviors[i], inf->exception_info.flavors[i]);
+      if (kret != KERN_SUCCESS)
+        return kret;
+    }
+
+  return KERN_SUCCESS;
+}
+
+static void
+darwin_attach_pid (int pid)
+{
+  task_t itask;
+  kern_return_t kret;
+  mach_port_t prev_port;
+  int traps_expected;
+  exception_mask_t mask;
+
+  kret = task_for_pid (gdb_task, pid, &itask);
+  if (kret != KERN_SUCCESS)
+    {
+      int status;
+      struct inferior *inf = current_inferior ();
+
+      if (!inf->attach_flag)
+	{
+	  kill (pid, 9);
+	  waitpid (pid, &status, 0);
+	}
+
+      error (_("Unable to find Mach task port for process-id %d: %s (0x%lx).\n"
+	       " (please check gdb is setgid procmod)"),
+             pid, mach_error_string (kret), (unsigned long) kret);
+    }
+
+  inferior_debug (2, _("inferior task: 0x%08x, pid: %d\n"), itask, pid);
+
+  if (darwin_ex_port == MACH_PORT_NULL)
+    {
+      /* Create a port to get exceptions.  */
+      kret = mach_port_allocate (gdb_task, MACH_PORT_RIGHT_RECEIVE,
+				 &darwin_ex_port);
+      gdb_assert (kret == KERN_SUCCESS);
+
+      kret = mach_port_insert_right (gdb_task, darwin_ex_port, darwin_ex_port,
+				     MACH_MSG_TYPE_MAKE_SEND);
+      gdb_assert (kret == KERN_SUCCESS);
+
+      /* Create a port set and put ex_port in it.  */
+      kret = mach_port_allocate (gdb_task, MACH_PORT_RIGHT_PORT_SET,
+				 &darwin_port_set);
+      gdb_assert (kret == KERN_SUCCESS);
+
+      kret = mach_port_move_member (gdb_task, darwin_ex_port, darwin_port_set);
+      gdb_assert (kret == KERN_SUCCESS);
+
+      /* Create a port to be notified when the child task terminates.  */
+      kret = mach_port_allocate (gdb_task, MACH_PORT_RIGHT_RECEIVE,
+				 &darwin_not_port);
+      gdb_assert (kret == KERN_SUCCESS);
+
+      kret = mach_port_insert_right (gdb_task, darwin_not_port, darwin_not_port,
+				     MACH_MSG_TYPE_MAKE_SEND);
+      gdb_assert (kret == KERN_SUCCESS);
+
+      kret = mach_port_move_member (gdb_task, darwin_not_port, darwin_port_set);
+      gdb_assert (kret == KERN_SUCCESS);
+    }
+
+  kret = mach_port_request_notification (gdb_task, itask,
+					 MACH_NOTIFY_DEAD_NAME, 0,
+					 darwin_not_port,
+					 MACH_MSG_TYPE_MAKE_SEND_ONCE,
+					 &darwin_inf->prev_not_port);
+  gdb_assert (kret == KERN_SUCCESS);
+
+  darwin_inf->task = itask;
+  darwin_inf->pid = pid;
+
+  kret = darwin_save_exception_ports (darwin_inf);
+  gdb_assert (kret == KERN_SUCCESS);
+
+  /* Set exception port.  */
+  if (enable_mach_exceptions)
+    mask = EXC_MASK_ALL;
+  else
+    mask = EXC_MASK_SOFTWARE;
+  kret = task_set_exception_ports
+    (itask, mask, darwin_ex_port, EXCEPTION_DEFAULT, THREAD_STATE_NONE);
+  gdb_assert (kret == KERN_SUCCESS);
+
+  push_target (darwin_ops);
+}
+
+static void
+darwin_init_thread_list (darwin_inferior *inf)
+{
+  thread_t thread;
+
+  darwin_check_new_threads (inf);
+
+  gdb_assert (inf->threads && VEC_length (thread_t, inf->threads) > 0);
+  thread = VEC_index (thread_t, inf->threads, 0);
+  inferior_ptid = ptid_build (inf->pid, 0, thread);
+}
+
+static void
+darwin_ptrace_him (int pid)
+{
+  task_t itask;
+  kern_return_t kret;
+  mach_port_t prev_port;
+  int traps_expected;
+
+  darwin_attach_pid (pid);
+
+  /* Let's the child run.  */
+  close (ptrace_fds[0]);
+  close (ptrace_fds[1]);
+
+  /* fork_inferior automatically add a thread - but it uses a wrong tid.  */
+  delete_thread_silent (inferior_ptid);
+  darwin_init_thread_list (darwin_inf);
+  
+  startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
+}
+
+static void
+darwin_create_inferior (struct target_ops *ops, char *exec_file,
+			char *allargs, char **env, int from_tty)
+{
+  /* Do the hard work.  */
+  fork_inferior (exec_file, allargs, env, darwin_ptrace_me, darwin_ptrace_him,
+		 darwin_pre_ptrace, NULL);
+  
+  /* Return now in case of error.  */
+  if (ptid_equal (inferior_ptid, null_ptid))
+    return;
+}
+
+
+/* Attach to process PID, then initialize for debugging it
+   and wait for the trace-trap that results from attaching.  */
+static void
+darwin_attach (struct target_ops *ops, char *args, int from_tty)
+{
+  pid_t pid;
+  pid_t pid2;
+  int wstatus;
+  int res;
+  struct inferior *inf;
+
+  gdb_assert (msg_state == NO_MESSAGE);
+
+  if (!args)
+    error_no_arg (_("process-id to attach"));
+
+  pid = atoi (args);
+
+  if (pid == getpid ())		/* Trying to masturbate? */
+    error (_("I refuse to debug myself!"));
+
+  if (from_tty)
+    printf_unfiltered (_("Attaching to pid %d\n"), pid);
+
+  res = PTRACE (PT_ATTACHEXC, pid, 0, 0);
+  if (res != 0)
+    error (_("Unable to attach to process-id %d: %s (%d)"),
+	   pid, strerror (errno), errno);
+
+  inf = add_inferior (pid);
+  inf->attach_flag = 1;
+
+  darwin_attach_pid (pid);
+
+  pid2 = wait4 (pid, &wstatus, WUNTRACED, NULL);
+  gdb_assert (pid2 == pid);
+  inferior_debug (1, _("darwin_attach: wait4 pid=%d, status=0x%x\n"),
+		  pid2, wstatus);
+
+  
+  darwin_init_thread_list (darwin_inf);
+
+  darwin_check_osabi (darwin_inf, ptid_get_tid (inferior_ptid));
+
+  /* Looks strange, but the kernel doesn't stop the process...
+     (Bug in Leopard ?)
+     Do it manually.  */
+  /* FIXME: doesn't look to work with multi-threads!!  */
+  kill (pid, SIGSTOP);
+}
+
+/* Take a program previously attached to and detaches it.
+   The program resumes execution and will no longer stop
+   on signals, etc.  We'd better not have left any breakpoints
+   in the program or it'll die when it hits one.  For this
+   to work, it may be necessary for the process to have been
+   previously attached.  It *might* work if the program was
+   started via fork.  */
+static void
+darwin_detach (struct target_ops *ops, char *args, int from_tty)
+{
+  kern_return_t kret;
+  int res;
+
+  if (from_tty)
+    {
+      char *exec_file = get_exec_file (0);
+      if (exec_file == 0)
+	exec_file = "";
+      printf_unfiltered (_("Detaching from program: %s, %d\n"), exec_file,
+			 ptid_get_pid (inferior_ptid));
+      gdb_flush (gdb_stdout);
+    }
+
+  darwin_stop_inferior (darwin_inf);
+
+  kret = darwin_restore_exception_ports (darwin_inf);
+  MACH_CHECK_ERROR (kret);
+
+  if (msg_state == GOT_MESSAGE)
+    {
+      exc_msg.ex_type = 0;
+      darwin_resume (inferior_ptid, 0, 0);
+    }
+
+  kret = task_resume (darwin_inf->task);
+  gdb_assert (kret == KERN_SUCCESS);
+
+  res = PTRACE (PT_DETACH, darwin_inf->pid, 0, 0);
+  if (res != 0)
+    printf_unfiltered (_("Unable to detach from process-id %d: %s (%d)"),
+		       darwin_inf->pid, strerror (errno), errno);
+
+  msg_state = NO_MESSAGE;
+
+  darwin_mourn_inferior (ops);
+}
+
+static void
+darwin_files_info (struct target_ops *ops)
+{
+  gdb_assert (darwin_inf != NULL);
+}
+
+static char *
+darwin_pid_to_str (ptid_t ptid)
+{
+  static char buf[128];
+
+  snprintf (buf, sizeof (buf),
+	    _("process %d gdb-thread 0x%lx"),
+	    (unsigned) ptid_get_pid (ptid),
+	    (unsigned long) ptid_get_tid (ptid));
+  return buf;
+}
+
+static int
+darwin_thread_alive (ptid_t ptid)
+{
+  return 1;
+}
+
+/* If RDADDR is not NULL, read inferior task's LEN bytes from ADDR and
+   copy it to RDADDR in gdb's address space.
+   If WRADDR is not NULL, write gdb's LEN bytes from WRADDR and copy it
+   to ADDR in inferior task's address space.
+   Return 0 on failure; number of bytes read / writen  otherwise.  */
+static int
+darwin_read_write_inferior (task_t task, CORE_ADDR addr,
+			    char *rdaddr, const char *wraddr, int length)
+{
+  kern_return_t err;
+  mach_vm_address_t offset = addr & (mach_page_size - 1);
+  mach_vm_address_t low_address = (mach_vm_address_t) (addr - offset);
+  mach_vm_size_t aligned_length = (mach_vm_size_t) PAGE_ROUND (offset + length);
+  pointer_t copied;
+  int copy_count;
+  mach_vm_size_t remaining_length;
+  mach_vm_address_t region_address;
+  mach_vm_size_t region_length;
+
+  inferior_debug (8, _("darwin_read_write_inferior(%s, len=%d)\n"),
+		  core_addr_to_string (addr), length);
+  
+  /* Get memory from inferior with page aligned addresses */
+  err = mach_vm_read (task, low_address, aligned_length,
+		      &copied, &copy_count);
+  if (err != KERN_SUCCESS)
+    {
+      warning (_("darwin_read_write_inferior: vm_read failed: %s"), 
+	       mach_error_string (err));
+      return 0;
+    }
+
+  if (rdaddr != NULL)
+    memcpy (rdaddr, (char *)copied + offset, length);
+
+  if (wraddr == NULL)
+    goto out;
+
+  memcpy ((char *)copied + offset, wraddr, length);
+
+  /* Do writes atomically.
+     First check for holes and unwritable memory.  */
+  for (region_address = low_address, remaining_length = aligned_length;
+       region_address < low_address + aligned_length;
+       region_address += region_length, remaining_length -= region_length)
+    {
+      vm_region_basic_info_data_64_t info;
+      mach_port_t object_name;
+      mach_vm_address_t old_address = region_address;
+      mach_msg_type_number_t count;
+      
+      region_length = remaining_length;
+      count = VM_REGION_BASIC_INFO_COUNT_64;
+      err = mach_vm_region (task, &region_address, &region_length,
+			    VM_REGION_BASIC_INFO_64,
+			    (vm_region_info_t) &info, &count, &object_name);
+      
+      if (err != KERN_SUCCESS)
+	{
+	  warning (_("darwin_write_inferior: mach_vm_region failed: %s"), 
+		   mach_error_string (err));
+	  goto out;
+	}
+
+      /* Check for holes in memory */
+      if (region_address > old_address)
+	{
+	  warning (_("No memory at %s (vs %s+0x%x). Nothing written"),
+		   core_addr_to_string (old_address),
+		   core_addr_to_string (region_address),
+		   (unsigned)region_length);
+	  length = 0;
+	  goto out;
+	}
+
+      if (!(info.max_protection & VM_PROT_WRITE))
+	{
+	  warning (_("Memory at address %s is unwritable. Nothing written"),
+		   core_addr_to_string (old_address));
+	  length = 0;
+	  goto out;
+	}
+
+      if (!(info.protection & VM_PROT_WRITE))
+	{
+	  err = mach_vm_protect (task, old_address, region_length,
+				 FALSE, info.protection | VM_PROT_WRITE);
+	  if (err != KERN_SUCCESS)
+	    {
+	      warning
+		(_("darwin_read_write_inferior: mach_vm_protect failed: %s"), 
+		 mach_error_string (err));
+	      length = 0;
+	      goto out;
+	    }
+	}
+    }
+
+  err = mach_vm_write (task, low_address, copied, aligned_length);
+
+  if (err != KERN_SUCCESS)
+    {
+      warning (_("darwin_read_write_inferior: mach_vm_write failed: %s"),
+	       mach_error_string (err));
+      length = 0;
+    }
+out:
+  mach_vm_deallocate (mach_task_self (), copied, copy_count);
+  return length;
+}
+
+
+/* Return 0 on failure, number of bytes handled otherwise.  TARGET
+   is ignored. */
+static int
+darwin_xfer_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len, int write,
+		    struct mem_attrib *attrib, struct target_ops *target)
+{
+  task_t task = darwin_inf->task;
+
+  if (task == MACH_PORT_NULL)
+    return 0;
+
+  inferior_debug (8, _("darwin_xfer_memory(%s, %d, %c)\n"),
+		  core_addr_to_string (memaddr), len, write ? 'w' : 'r');
+
+  if (write)
+    return darwin_read_write_inferior (task, memaddr, NULL, myaddr, len);
+  else
+    return darwin_read_write_inferior (task, memaddr, myaddr, NULL, len);
+}
+
+static LONGEST
+darwin_xfer_partial (struct target_ops *ops,
+		     enum target_object object, const char *annex,
+		     gdb_byte *readbuf, const gdb_byte *writebuf,
+		     ULONGEST offset, LONGEST len)
+{
+  inferior_debug (8, _("darwin_xfer_partial(%s, %d, rbuf=%p, wbuf=%p)\n"),
+		  core_addr_to_string (offset), (int)len, readbuf, writebuf);
+
+  if (object != TARGET_OBJECT_MEMORY)
+    return -1;
+
+  return darwin_read_write_inferior (darwin_inf->task, offset,
+				     readbuf, writebuf, len);
+}
+
+static void
+set_enable_mach_exceptions (char *args, int from_tty,
+			    struct cmd_list_element *c)
+{
+  if (darwin_inf && darwin_inf->task != TASK_NULL)
+    {
+      exception_mask_t mask;
+      kern_return_t kret;
+
+      if (enable_mach_exceptions)
+	mask = EXC_MASK_ALL;
+      else
+	{
+	  darwin_restore_exception_ports (darwin_inf);
+	  mask = EXC_MASK_SOFTWARE;
+	}
+      kret = task_set_exception_ports (darwin_inf->task, mask, darwin_ex_port,
+				       EXCEPTION_DEFAULT, THREAD_STATE_NONE);
+      MACH_CHECK_ERROR (kret);
+    }
+}
+
+void
+_initialize_darwin_inferior ()
+{
+  kern_return_t kret;
+
+  gdb_assert (darwin_inf == NULL);
+  
+  gdb_task = mach_task_self ();
+  darwin_host_self = mach_host_self ();
+
+  /* Read page size.  */
+  kret = host_page_size (darwin_host_self, &mach_page_size);
+  if (kret != KERN_SUCCESS)
+    {
+      mach_page_size = 0x1000;
+      MACH_CHECK_ERROR (kret);
+    }
+
+  darwin_inf = (struct darwin_inferior *)
+    xmalloc (sizeof (struct darwin_inferior));
+
+  memset (darwin_inf, 0, sizeof (*darwin_inf));
+
+  darwin_ops = inf_child_target ();
+
+  darwin_ops->to_shortname = "darwin-child";
+  darwin_ops->to_longname = _("Darwin child process");
+  darwin_ops->to_doc =
+    _("Darwin child process (started by the \"run\" command).");
+  darwin_ops->to_create_inferior = darwin_create_inferior;
+  darwin_ops->to_attach = darwin_attach;
+  darwin_ops->to_attach_no_wait = 0;
+  darwin_ops->to_detach = darwin_detach;
+  darwin_ops->to_files_info = darwin_files_info;
+  darwin_ops->to_wait = darwin_wait;
+  darwin_ops->to_mourn_inferior = darwin_mourn_inferior;
+  darwin_ops->to_kill = darwin_kill_inferior;
+  darwin_ops->to_stop = darwin_stop;
+  darwin_ops->to_resume = darwin_resume;
+  darwin_ops->to_thread_alive = darwin_thread_alive;
+  darwin_ops->to_pid_to_str = darwin_pid_to_str;
+  darwin_ops->to_load = NULL;
+  darwin_ops->deprecated_xfer_memory = darwin_xfer_memory;
+  darwin_ops->to_xfer_partial = darwin_xfer_partial;
+  darwin_ops->to_has_thread_control = tc_schedlock /*| tc_switch */;
+
+  darwin_complete_target (darwin_ops);
+
+  add_target (darwin_ops);
+
+  inferior_debug (2, _("GDB task: 0x%lx, pid: %d\n"), mach_task_self (),
+                  getpid ());
+
+  add_setshow_zinteger_cmd ("darwin", class_obscure,
+			    &darwin_debug_flag, _("\
+Set if printing inferior communication debugging statements."), _("\
+Show if printing inferior communication debugging statements."), NULL,
+			    NULL, NULL,
+			    &setdebuglist, &showdebuglist);
+
+  add_setshow_boolean_cmd ("mach-exceptions", class_support,
+			   &enable_mach_exceptions, _("\
+Set if mach exceptions are caught."), _("\
+Show if mach exceptions are caught."), _("\
+When this mode is on, all low level exceptions are reported before being\n\
+reported by the kernel."),
+			   &set_enable_mach_exceptions, NULL,
+			   &setlist, &showlist);
+}
diff --git a/gdb/darwin-nat.h b/gdb/darwin-nat.h
new file mode 100644
index 00000000000..43e48dda5a5
--- /dev/null
+++ b/gdb/darwin-nat.h
@@ -0,0 +1,107 @@
+/* Common things used by the various darwin files
+   Copyright (C) 1995, 1996, 1997, 1999, 2000, 2007, 2008
+   Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __DARWIN_NAT_H__
+#define __DARWIN_NAT_H__
+
+#include <mach/mach.h>
+#include "gdb_assert.h"
+
+/* Define the threads vector type.  */
+DEF_VEC_I (thread_t);
+
+/* Describe the mach exception handling state for a task.  This state is saved
+   before being changed and restored when a process is detached.
+   For more information on these fields see task_get_exception_ports manual
+   page.  */
+struct darwin_exception_info
+{
+  /* Exceptions handled by the port.  */
+  exception_mask_t masks[EXC_TYPES_COUNT];
+
+  /* Ports receiving exception messages.  */
+  mach_port_t ports[EXC_TYPES_COUNT];
+
+  /* Type of messages sent.  */
+  exception_behavior_t behaviors[EXC_TYPES_COUNT];
+
+  /* Type of state to be sent.  */
+  thread_state_flavor_t flavors[EXC_TYPES_COUNT];
+
+  /* Number of elements set.  */
+  mach_msg_type_number_t count;
+};
+typedef struct darwin_exception_info darwin_exception_info;
+
+/* Describe an inferior.  */
+struct darwin_inferior
+{
+  /* Inferior PID.  */
+  int pid;
+
+  /* Corresponding task port.  */
+  task_t task;
+
+  /* Previous port for request notification on task.  */
+  mach_port_t prev_not_port;
+
+  /* Initial exception handling.  */
+  darwin_exception_info exception_info;
+
+  /* Sorted vector of known threads.  */
+  VEC(thread_t) *threads;
+};
+typedef struct darwin_inferior darwin_inferior;
+
+/* Current inferior.  */
+extern darwin_inferior *darwin_inf;
+
+/* Exception port.  */
+extern mach_port_t darwin_ex_port;
+
+/* Notification port.  */
+extern mach_port_t darwin_not_port;
+
+/* Port set.  */
+extern mach_port_t darwin_port_set;
+
+/* A copy of mach_host_self ().  */
+extern mach_port_t darwin_host_self;
+
+/* ASSERT_FUNCTION is defined in gdb_assert.h (or not).  */
+#ifdef ASSERT_FUNCTION
+#define MACH_CHECK_ERROR(ret) \
+  mach_check_error (ret, __FILE__, __LINE__, ASSERT_FUNCTION)
+#else
+#define MACH_CHECK_ERROR(ret) \
+  mach_check_error (ret, __FILE__, __LINE__, "??")
+#endif
+
+extern void mach_check_error (kern_return_t ret, const char *file,
+			      unsigned int line, const char *func);
+
+void darwin_set_sstep (thread_t thread, int enable);
+
+/* This one is called in darwin-nat.c, but needs to be provided by the
+   platform specific nat code.  It allows each platform to add platform specific
+   stuff to the darwin_ops.  */
+extern void darwin_complete_target (struct target_ops *target);
+
+void darwin_check_osabi (darwin_inferior *inf, thread_t thread);
+
+#endif /* __DARWIN_NAT_H__ */
diff --git a/gdb/darwin.defs b/gdb/darwin.defs
new file mode 100644
index 00000000000..d7b5f0d1c65
--- /dev/null
+++ b/gdb/darwin.defs
@@ -0,0 +1,6 @@
+#include "config.h"
+#ifdef HAVE_64_BIT_MACH_EXCEPTIONS
+#import <mach/mach_exc.defs>
+#else
+#import <mach/exc.defs>
+#endif
diff --git a/gdb/defs.h b/gdb/defs.h
index b04726693d5..415c656cf85 100644
--- a/gdb/defs.h
+++ b/gdb/defs.h
@@ -957,6 +957,7 @@ enum gdb_osabi
   GDB_OSABI_CYGWIN,
   GDB_OSABI_AIX,
   GDB_OSABI_DICOS,
+  GDB_OSABI_DARWIN,
 
   GDB_OSABI_INVALID		/* keep this last */
 };
diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog
index 350831be8f2..9f4ec6d5bfb 100644
--- a/gdb/doc/ChangeLog
+++ b/gdb/doc/ChangeLog
@@ -1,3 +1,7 @@
+2008-11-27  Tristan Gingold  <gingold@adacore.com>
+
+	* gdb.texinfo (Darwin): Document Darwin specific features.
+
 2008-11-25  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
 	* gdbint.texinfo (Target Conditionals): Extend the
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 3c54c43d529..2a86017cf54 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -14675,6 +14675,7 @@ configurations.
 * Cygwin Native::		Features specific to the Cygwin port
 * Hurd Native::                 Features specific to @sc{gnu} Hurd
 * Neutrino::                    Features specific to QNX Neutrino
+* Darwin::			Features specific to Darwin
 @end menu
 
 @node HP-UX
@@ -15456,6 +15457,48 @@ Neutrino support.
 Show the current state of QNX Neutrino messages.
 @end table
 
+@node Darwin
+@subsection Darwin
+@cindex Darwin
+
+@value{GDBN} provides the following commands specific to the Darwin target:
+
+@table @code
+@item set debug darwin @var{num}
+@kindex set debug darwin
+When set to a non zero value, enables debugging messages specific to
+the Darwin support.  Higher values produce more verbose output.
+
+@item show debug darwin
+@kindex show debug darwin
+Show the current state of Darwin messages.
+
+@item set debug mach-o @var{num}
+@kindex set debug mach-o
+When set to a non zero value, enables debugging messages while
+@value{GDBN} is reading Darwin object files.  (@dfn{Mach-O} is the
+file format used on Darwin for object and executable files.)  Higher
+values produce more verbose output.  This is a command to diagnose
+problems internal to @value{GDBN} and should not be needed in normal
+usage.
+
+@item show debug mach-o
+@kindex show debug mach-o
+Show the current state of Mach-O file messages.
+
+@item set mach-exceptions on
+@itemx set mach-exceptions off
+@kindex set mach-exceptions
+On Darwin, faults are first reported as a Mach exception and are then
+mapped to a Posix signal.  Use this command to turn on trapping of
+Mach exceptions in the inferior.  This might be sometimes useful to
+better understand the cause of a fault.  The default is off.
+
+@item show mach-exceptions
+@kindex show mach-exceptions
+Show the current state of exceptions trapping.
+@end table
+
 
 @node Embedded OS
 @section Embedded Operating Systems
diff --git a/gdb/i386-darwin-nat.c b/gdb/i386-darwin-nat.c
new file mode 100644
index 00000000000..03051738699
--- /dev/null
+++ b/gdb/i386-darwin-nat.c
@@ -0,0 +1,492 @@
+/* Darwin support for GDB, the GNU debugger.
+   Copyright 1997, 1998, 1999, 2000, 2001, 2002, 2008
+   Free Software Foundation, Inc.
+
+   Contributed by Apple Computer, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include "defs.h"
+#include "frame.h"
+#include "inferior.h"
+#include "target.h"
+#include "symfile.h"
+#include "symtab.h"
+#include "objfiles.h"
+#include "gdbcmd.h"
+#include "regcache.h"
+#include "gdb_assert.h"
+#include "i386-tdep.h"
+#include "amd64-nat.h"
+#include "i387-tdep.h"
+#include "gdbarch.h"
+#include "arch-utils.h"
+
+#include "darwin-nat.h"
+#include "i386-darwin-tdep.h"
+
+/* Read register values from the inferior process.
+   If REGNO is -1, do this for all registers.
+   Otherwise, REGNO specifies which register (so we can save time).  */
+static void
+i386_darwin_fetch_inferior_registers (struct regcache *regcache, int regno)
+{
+  thread_t current_thread = ptid_get_tid (inferior_ptid);
+  int fetched = 0;
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+
+  if (gdbarch_ptr_bit (gdbarch) == 64)
+    {
+      if (regno == -1 || amd64_native_gregset_supplies_p (gdbarch, regno))
+        {
+          x86_thread_state_t gp_regs;
+          unsigned int gp_count = x86_THREAD_STATE_COUNT;
+          kern_return_t ret;
+
+	  ret = thread_get_state
+            (current_thread, x86_THREAD_STATE, (thread_state_t) & gp_regs,
+             &gp_count);
+	  if (ret != KERN_SUCCESS)
+	    {
+	      printf_unfiltered (_("Error calling thread_get_state for GP registers for thread 0x%ulx"), current_thread);
+	      MACH_CHECK_ERROR (ret);
+	    }
+	  amd64_supply_native_gregset (regcache, &gp_regs.uts, -1);
+          fetched++;
+        }
+
+      if (regno == -1 || !amd64_native_gregset_supplies_p (gdbarch, regno))
+        {
+          x86_float_state_t fp_regs;
+          unsigned int fp_count = x86_FLOAT_STATE_COUNT;
+          kern_return_t ret;
+
+	  ret = thread_get_state
+            (current_thread, x86_FLOAT_STATE, (thread_state_t) & fp_regs,
+             &fp_count);
+	  if (ret != KERN_SUCCESS)
+	    {
+	      printf_unfiltered (_("Error calling thread_get_state for float registers for thread 0x%ulx"), current_thread);
+	      MACH_CHECK_ERROR (ret);
+	    }
+          i387_supply_fxsave (regcache, -1, &fp_regs.ufs.fs64);
+          fetched++;
+        }
+    }
+  else
+    {
+      if (regno == -1 || regno < I386_NUM_GREGS)
+        {
+          i386_thread_state_t gp_regs;
+          unsigned int gp_count = i386_THREAD_STATE_COUNT;
+          kern_return_t ret;
+	  int i;
+
+	  ret = thread_get_state
+            (current_thread, i386_THREAD_STATE, (thread_state_t) & gp_regs,
+             &gp_count);
+	  if (ret != KERN_SUCCESS)
+	    {
+	      printf_unfiltered (_("Error calling thread_get_state for GP registers for thread 0x%ulx"), current_thread);
+	      MACH_CHECK_ERROR (ret);
+	    }
+	  for (i = 0; i < I386_NUM_GREGS; i++)
+	    regcache_raw_supply
+	      (regcache, i,
+	       (char *)&gp_regs + i386_darwin_thread_state_reg_offset[i]);
+
+          fetched++;
+        }
+
+      if (regno == -1
+	  || (regno >= I386_ST0_REGNUM && regno < I386_SSE_NUM_REGS))
+        {
+          i386_float_state_t fp_regs;
+          unsigned int fp_count = i386_FLOAT_STATE_COUNT;
+          kern_return_t ret;
+
+	  ret = thread_get_state
+            (current_thread, i386_FLOAT_STATE, (thread_state_t) & fp_regs,
+             &fp_count);
+	  if (ret != KERN_SUCCESS)
+	    {
+	      printf_unfiltered (_("Error calling thread_get_state for float registers for thread 0x%ulx"), current_thread);
+	      MACH_CHECK_ERROR (ret);
+	    }
+          i387_supply_fxsave (regcache, -1, &fp_regs.__fpu_fcw);
+          fetched++;
+        }
+    }
+
+  if (! fetched)
+    {
+      warning (_("unknown register %d"), regno);
+      regcache_raw_supply (regcache, regno, NULL);
+    }
+}
+
+/* Store our register values back into the inferior.
+   If REGNO is -1, do this for all registers.
+   Otherwise, REGNO specifies which register (so we can save time).  */
+
+static void
+i386_darwin_store_inferior_registers (struct regcache *regcache, int regno)
+{
+  thread_t current_thread = ptid_get_tid (inferior_ptid);
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+
+  if (gdbarch_ptr_bit (gdbarch) == 64)
+    {
+      if (regno == -1 || amd64_native_gregset_supplies_p (gdbarch, regno))
+        {
+          x86_thread_state_t gp_regs;
+          kern_return_t ret;
+	  unsigned int gp_count = x86_THREAD_STATE_COUNT;
+
+	  ret = thread_get_state
+	    (current_thread, x86_THREAD_STATE, (thread_state_t) &gp_regs,
+	     &gp_count);
+          MACH_CHECK_ERROR (ret);
+	  gdb_assert (gp_regs.tsh.flavor == x86_THREAD_STATE64);
+          gdb_assert (gp_regs.tsh.count == x86_THREAD_STATE64_COUNT);
+
+	  amd64_collect_native_gregset (regcache, &gp_regs.uts, regno);
+
+          ret = thread_set_state (current_thread, x86_THREAD_STATE,
+                                  (thread_state_t) &gp_regs,
+                                  x86_THREAD_STATE_COUNT);
+          MACH_CHECK_ERROR (ret);
+        }
+
+      if (regno == -1 || !amd64_native_gregset_supplies_p (gdbarch, regno))
+        {
+          x86_float_state_t fp_regs;
+          kern_return_t ret;
+	  unsigned int fp_count = x86_FLOAT_STATE_COUNT;
+
+	  ret = thread_get_state
+	    (current_thread, x86_FLOAT_STATE, (thread_state_t) & fp_regs,
+	     &fp_count);
+          MACH_CHECK_ERROR (ret);
+          gdb_assert (fp_regs.fsh.flavor == x86_FLOAT_STATE64);
+          gdb_assert (fp_regs.fsh.count == x86_FLOAT_STATE64_COUNT);
+
+	  i387_collect_fxsave (regcache, regno, &fp_regs.ufs.fs64.__fpu_fcw);
+
+	  ret = thread_set_state (current_thread, x86_FLOAT_STATE,
+				  (thread_state_t) & fp_regs,
+				  x86_FLOAT_STATE_COUNT);
+	  MACH_CHECK_ERROR (ret);
+        }
+    }
+  else
+    {
+      if (regno == -1 || regno < I386_NUM_GREGS)
+        {
+          i386_thread_state_t gp_regs;
+          kern_return_t ret;
+          unsigned int gp_count = i386_THREAD_STATE_COUNT;
+	  int i;
+
+          ret = thread_get_state
+            (current_thread, i386_THREAD_STATE, (thread_state_t) & gp_regs,
+             &gp_count);
+	  MACH_CHECK_ERROR (ret);
+
+	  for (i = 0; i < I386_NUM_GREGS; i++)
+	    if (regno == -1 || regno == i)
+	      regcache_raw_collect
+		(regcache, i,
+		 (char *)&gp_regs + i386_darwin_thread_state_reg_offset[i]);
+
+          ret = thread_set_state (current_thread, i386_THREAD_STATE,
+                                  (thread_state_t) & gp_regs,
+                                  i386_THREAD_STATE_COUNT);
+          MACH_CHECK_ERROR (ret);
+        }
+
+      if (regno == -1
+	  || (regno >= I386_ST0_REGNUM && regno < I386_SSE_NUM_REGS))
+        {
+          i386_float_state_t fp_regs;
+          unsigned int fp_count = i386_FLOAT_STATE_COUNT;
+          kern_return_t ret;
+
+	  ret = thread_get_state
+            (current_thread, i386_FLOAT_STATE, (thread_state_t) & fp_regs,
+             &fp_count);
+	  MACH_CHECK_ERROR (ret);
+
+	  i387_collect_fxsave (regcache, regno, &fp_regs.__fpu_fcw);
+
+	  ret = thread_set_state (current_thread, i386_FLOAT_STATE,
+				  (thread_state_t) & fp_regs,
+				  i386_FLOAT_STATE_COUNT);
+	  MACH_CHECK_ERROR (ret);
+        }
+    }
+}
+
+
+/* Support for debug registers, boosted mostly from i386-linux-nat.c.  */
+
+#ifndef DR_FIRSTADDR
+#define DR_FIRSTADDR 0
+#endif
+
+#ifndef DR_LASTADDR
+#define DR_LASTADDR 3
+#endif
+
+#ifndef DR_STATUS
+#define DR_STATUS 6
+#endif
+
+#ifndef DR_CONTROL
+#define DR_CONTROL 7
+#endif
+
+
+static void
+i386_darwin_dr_set (int regnum, uint32_t value)
+{
+  int current_pid;
+  thread_t current_thread;
+  x86_debug_state_t dr_regs;
+  kern_return_t ret;
+  unsigned int dr_count = x86_DEBUG_STATE_COUNT;
+
+  gdb_assert (regnum >= 0 && regnum <= DR_CONTROL);
+
+  current_thread = ptid_get_tid (inferior_ptid);
+
+  dr_regs.dsh.flavor = x86_DEBUG_STATE32;
+  dr_regs.dsh.count = x86_DEBUG_STATE32_COUNT;
+  dr_count = x86_DEBUG_STATE_COUNT;
+  ret = thread_get_state (current_thread, x86_DEBUG_STATE, 
+                          (thread_state_t) &dr_regs, &dr_count);
+
+  if (ret != KERN_SUCCESS)
+    {
+      printf_unfiltered (_("Error reading debug registers thread 0x%x via thread_get_state\n"), (int) current_thread);
+      MACH_CHECK_ERROR (ret);
+    }
+
+  switch (regnum) 
+    {
+      case 0:
+        dr_regs.uds.ds32.__dr0 = value;
+        break;
+      case 1:
+        dr_regs.uds.ds32.__dr1 = value;
+        break;
+      case 2:
+        dr_regs.uds.ds32.__dr2 = value;
+        break;
+      case 3:
+        dr_regs.uds.ds32.__dr3 = value;
+        break;
+      case 4:
+        dr_regs.uds.ds32.__dr4 = value;
+        break;
+      case 5:
+        dr_regs.uds.ds32.__dr5 = value;
+        break;
+      case 6:
+        dr_regs.uds.ds32.__dr6 = value;
+        break;
+      case 7:
+        dr_regs.uds.ds32.__dr7 = value;
+        break;
+    }
+
+  ret = thread_set_state (current_thread, x86_DEBUG_STATE, 
+                          (thread_state_t) &dr_regs, dr_count);
+
+  if (ret != KERN_SUCCESS)
+    {
+      printf_unfiltered (_("Error writing debug registers thread 0x%x via thread_get_state\n"), (int) current_thread);
+      MACH_CHECK_ERROR (ret);
+    }
+}
+
+static uint32_t
+i386_darwin_dr_get (int regnum)
+{
+  thread_t current_thread;
+  x86_debug_state_t dr_regs;
+  kern_return_t ret;
+  unsigned int dr_count = x86_DEBUG_STATE_COUNT;
+
+  gdb_assert (regnum >= 0 && regnum <= DR_CONTROL);
+
+  current_thread = ptid_get_tid (inferior_ptid);
+
+  dr_regs.dsh.flavor = x86_DEBUG_STATE32;
+  dr_regs.dsh.count = x86_DEBUG_STATE32_COUNT;
+  dr_count = x86_DEBUG_STATE_COUNT;
+  ret = thread_get_state (current_thread, x86_DEBUG_STATE, 
+                          (thread_state_t) &dr_regs, &dr_count);
+
+  if (ret != KERN_SUCCESS)
+    {
+      printf_unfiltered (_("Error reading debug registers thread 0x%x via thread_get_state\n"), (int) current_thread);
+      MACH_CHECK_ERROR (ret);
+    }
+
+  switch (regnum) 
+    {
+      case 0:
+        return dr_regs.uds.ds32.__dr0;
+      case 1:
+        return dr_regs.uds.ds32.__dr1;
+      case 2:
+        return dr_regs.uds.ds32.__dr2;
+      case 3:
+        return dr_regs.uds.ds32.__dr3;
+      case 4:
+        return dr_regs.uds.ds32.__dr4;
+      case 5:
+        return dr_regs.uds.ds32.__dr5;
+      case 6:
+        return dr_regs.uds.ds32.__dr6;
+      case 7:
+        return dr_regs.uds.ds32.__dr7;
+      default:
+        return -1;
+    }
+}
+
+void
+i386_darwin_dr_set_control (unsigned long control)
+{
+  i386_darwin_dr_set (DR_CONTROL, control);
+}
+
+void
+i386_darwin_dr_set_addr (int regnum, CORE_ADDR addr)
+{
+  gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);
+
+  i386_darwin_dr_set (DR_FIRSTADDR + regnum, addr);
+}
+
+void
+i386_darwin_dr_reset_addr (int regnum)
+{
+  gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);
+
+  i386_darwin_dr_set (DR_FIRSTADDR + regnum, 0L);
+}
+
+unsigned long
+i386_darwin_dr_get_status (void)
+{
+  return i386_darwin_dr_get (DR_STATUS);
+}
+
+void
+darwin_check_osabi (darwin_inferior *inf, thread_t thread)
+{
+  if (gdbarch_osabi (current_gdbarch) == GDB_OSABI_UNKNOWN)
+    {
+      /* Attaching to a process.  Let's figure out what kind it is.  */
+      x86_thread_state_t gp_regs;
+      struct gdbarch_info info;
+      unsigned int gp_count = x86_THREAD_STATE_COUNT;
+      kern_return_t ret;
+
+      ret = thread_get_state (thread, x86_THREAD_STATE,
+			      (thread_state_t) &gp_regs, &gp_count);
+      if (ret != KERN_SUCCESS)
+	{
+	  MACH_CHECK_ERROR (ret);
+	  return;
+	}
+
+      gdbarch_info_init (&info);
+      gdbarch_info_fill (&info);
+      info.byte_order = gdbarch_byte_order (current_gdbarch);
+      info.osabi = GDB_OSABI_DARWIN;
+      if (gp_regs.tsh.flavor == x86_THREAD_STATE64)
+	info.bfd_arch_info = bfd_lookup_arch (bfd_arch_i386,
+					      bfd_mach_x86_64);
+      else
+	info.bfd_arch_info = bfd_lookup_arch (bfd_arch_i386, 
+					      bfd_mach_i386_i386);
+      gdbarch_update_p (info);
+    }
+}
+
+#define X86_EFLAGS_T 0x100UL
+
+void
+darwin_set_sstep (thread_t thread, int enable)
+{
+  x86_thread_state_t regs;
+  unsigned int count = x86_THREAD_STATE_COUNT;
+  kern_return_t kret;
+
+  kret = thread_get_state (thread, x86_THREAD_STATE,
+			   (thread_state_t) &regs, &count);
+  if (kret != KERN_SUCCESS)
+    {
+      printf_unfiltered (_("darwin_set_sstep: error %x, thread=%x\n"),
+			 kret, thread);
+      return;
+    }
+  switch (regs.tsh.flavor)
+    {
+    case x86_THREAD_STATE32:
+      {
+	__uint32_t bit = enable ? X86_EFLAGS_T : 0;
+	
+	if ((regs.uts.ts32.__eflags & X86_EFLAGS_T) == bit)
+	  return;
+	regs.uts.ts32.__eflags = (regs.uts.ts32.__eflags & ~X86_EFLAGS_T) | bit;
+	kret = thread_set_state (thread, x86_THREAD_STATE, 
+				 (thread_state_t) &regs, count);
+	MACH_CHECK_ERROR (kret);
+      }
+      break;
+    case x86_THREAD_STATE64:
+      {
+	__uint64_t bit = enable ? X86_EFLAGS_T : 0;
+
+	if ((regs.uts.ts64.__rflags & X86_EFLAGS_T) == bit)
+	  return;
+	regs.uts.ts64.__rflags = (regs.uts.ts64.__rflags & ~X86_EFLAGS_T) | bit;
+	kret = thread_set_state (thread, x86_THREAD_STATE, 
+				 (thread_state_t) &regs, count);
+	MACH_CHECK_ERROR (kret);
+      }
+      break;
+    default:
+      error (_("darwin_set_sstep: unknown flavour: %d\n"), regs.tsh.flavor);
+    }
+}
+
+void
+darwin_complete_target (struct target_ops *target)
+{
+  amd64_native_gregset64_reg_offset = amd64_darwin_thread_state_reg_offset;
+  amd64_native_gregset64_num_regs = amd64_darwin_thread_state_num_regs;
+  amd64_native_gregset32_reg_offset = i386_darwin_thread_state_reg_offset;
+  amd64_native_gregset32_num_regs = i386_darwin_thread_state_num_regs;
+
+  target->to_fetch_registers = i386_darwin_fetch_inferior_registers;
+  target->to_store_registers = i386_darwin_store_inferior_registers;
+}
diff --git a/gdb/i386-darwin-tdep.c b/gdb/i386-darwin-tdep.c
new file mode 100644
index 00000000000..522fe636be5
--- /dev/null
+++ b/gdb/i386-darwin-tdep.c
@@ -0,0 +1,159 @@
+/* Darwin support for GDB, the GNU debugger.
+   Copyright 1997, 1998, 1999, 2000, 2001, 2002, 2005, 2008
+   Free Software Foundation, Inc.
+
+   Contributed by Apple Computer, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include "defs.h"
+#include "frame.h"
+#include "inferior.h"
+#include "gdbcore.h"
+#include "target.h"
+#include "floatformat.h"
+#include "symtab.h"
+#include "regcache.h"
+#include "libbfd.h"
+#include "objfiles.h"
+
+#include "i387-tdep.h"
+#include "i386-tdep.h"
+#include "amd64-tdep.h"
+#include "osabi.h"
+#include "ui-out.h"
+#include "symtab.h"
+#include "frame.h"
+#include "gdb_assert.h"
+#include "i386-darwin-tdep.h"
+
+/* Offsets into the struct i386_thread_state where we'll find the saved regs.
+   From <mach/i386/thread_status.h> and i386-tdep.h.  */
+int i386_darwin_thread_state_reg_offset[] =
+{
+   0 * 4,   /* EAX */
+   2 * 4,   /* ECX */
+   3 * 4,   /* EDX */
+   1 * 4,   /* EBX */
+   7 * 4,   /* ESP */
+   6 * 4,   /* EBP */
+   5 * 4,   /* ESI */
+   4 * 4,   /* EDI */
+  10 * 4,   /* EIP */
+   9 * 4,   /* EFLAGS */
+  11 * 4,   /* CS */
+   8,       /* SS */
+  12 * 4,   /* DS */
+  13 * 4,   /* ES */
+  14 * 4,   /* FS */
+  15 * 4    /* GS */
+};
+
+const int i386_darwin_thread_state_num_regs = 
+  ARRAY_SIZE (i386_darwin_thread_state_reg_offset);
+
+/* Offsets into the struct x86_thread_state64 where we'll find the saved regs.
+   From <mach/i386/thread_status.h> and amd64-tdep.h.  */
+int amd64_darwin_thread_state_reg_offset[] =
+{
+  0 * 8,			/* %rax */
+  1 * 8,			/* %rbx */
+  2 * 8,			/* %rcx */
+  3 * 8,			/* %rdx */
+  5 * 8,			/* %rsi */
+  4 * 8,			/* %rdi */
+  6 * 8,			/* %rbp */
+  7 * 8,			/* %rsp */
+  8 * 8,			/* %r8 ... */
+  9 * 8,
+  10 * 8,
+  11 * 8,
+  12 * 8,
+  13 * 8,
+  14 * 8,
+  15 * 8,			/* ... %r15 */
+  16 * 8,			/* %rip */
+  17 * 8,			/* %rflags */
+  18 * 8,			/* %cs */
+  -1,				/* %ss */
+  -1,				/* %ds */
+  -1,				/* %es */
+  19 * 8,			/* %fs */
+  20 * 8			/* %gs */
+};
+
+const int amd64_darwin_thread_state_num_regs = 
+  ARRAY_SIZE (amd64_darwin_thread_state_reg_offset);
+
+static void
+i386_darwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+  /* We support the SSE registers.  */
+  tdep->num_xmm_regs = I386_NUM_XREGS - 1;
+  set_gdbarch_num_regs (gdbarch, I386_SSE_NUM_REGS);
+
+  tdep->struct_return = reg_struct_return;
+
+  tdep->sigcontext_addr = NULL;
+  tdep->sc_reg_offset = i386_darwin_thread_state_reg_offset;
+  tdep->sc_num_regs = 16;
+
+  tdep->jb_pc_offset = 20;
+}
+
+static void
+x86_darwin_init_abi_64 (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+  amd64_init_abi (info, gdbarch);
+
+  tdep->struct_return = reg_struct_return;
+
+  /* We don't do signals yet.  */
+  tdep->sigcontext_addr = NULL;
+  tdep->sc_reg_offset = amd64_darwin_thread_state_reg_offset;
+  tdep->sc_num_regs = ARRAY_SIZE (amd64_darwin_thread_state_reg_offset);
+
+  tdep->jb_pc_offset = 148;
+}
+
+static enum gdb_osabi
+i386_mach_o_osabi_sniffer (bfd *abfd)
+{
+  if (!bfd_check_format (abfd, bfd_object))
+    return GDB_OSABI_UNKNOWN;
+  
+  if (bfd_get_arch (abfd) == bfd_arch_i386)
+    return GDB_OSABI_DARWIN;
+
+  return GDB_OSABI_UNKNOWN;
+}
+
+void
+_initialize_i386_darwin_tdep (void)
+{
+  gdbarch_register_osabi_sniffer (bfd_arch_unknown, bfd_target_mach_o_flavour,
+                                  i386_mach_o_osabi_sniffer);
+
+  gdbarch_register_osabi (bfd_arch_i386, bfd_mach_i386_i386,
+			  GDB_OSABI_DARWIN, i386_darwin_init_abi);
+
+  gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
+                          GDB_OSABI_DARWIN, x86_darwin_init_abi_64);
+}
diff --git a/gdb/i386-darwin-tdep.h b/gdb/i386-darwin-tdep.h
new file mode 100644
index 00000000000..209ca1273f9
--- /dev/null
+++ b/gdb/i386-darwin-tdep.h
@@ -0,0 +1,33 @@
+/* Target-dependent code for Darwin x86.
+
+   Copyright (C) 2008 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+#ifndef __I386_DARWIN_TDEP_H__
+#define __I386_DARWIN_TDEP_H__
+
+/* Mapping between the general-purpose registers in Darwin x86 thread_state
+   struct and GDB's register cache layout.  */
+extern int i386_darwin_thread_state_reg_offset[];
+extern const int i386_darwin_thread_state_num_regs;
+
+/* Mapping between the general-purpose registers in Darwin x86-64 thread
+   state and GDB's register cache layout.
+   Indexed by amd64_regnum.  */
+extern int amd64_darwin_thread_state_reg_offset[];
+extern const int amd64_darwin_thread_state_num_regs;
+
+#endif /* __I386_DARWIN_TDEP_H__ */
diff --git a/gdb/machoread.c b/gdb/machoread.c
new file mode 100644
index 00000000000..f15495f34e6
--- /dev/null
+++ b/gdb/machoread.c
@@ -0,0 +1,694 @@
+/* Darwin support for GDB, the GNU debugger.
+   Copyright (C) 2008 Free Software Foundation, Inc.
+
+   Contributed by AdaCore.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "defs.h"
+#include "symtab.h"
+#include "gdbtypes.h"
+#include "bfd.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "buildsym.h"
+#include "gdbcmd.h"
+#include "gdbcore.h"
+#include "mach-o.h"
+#include "gdb_assert.h"
+#include "aout/stab_gnu.h"
+#include "vec.h"
+
+#include <string.h>
+
+/* If non-zero displays debugging message.  */
+static int mach_o_debug_level = 0;
+
+static void
+macho_new_init (struct objfile *objfile)
+{
+}
+
+static void
+macho_symfile_init (struct objfile *objfile)
+{
+  objfile->flags |= OBJF_REORDERED;
+  init_entry_point_info (objfile);
+}
+
+/* Dwarf debugging information are never in the final executable.  They stay
+   in object files and the executable contains the list of object files read
+   during the link.
+   Each time an oso (other source) is found in the executable, the reader
+   creates such a structure.  They are read after the processing of the
+   executable.
+*/
+typedef struct oso_el
+{
+  /* Object file name.  */
+  const char *name;
+
+  /* Associated time stamp.  */
+  unsigned long mtime;
+
+  /* Number of sections.  This is the length of SYMBOLS and OFFSETS array.  */
+  int num_sections;
+
+  /* Each seaction of the object file is represented by a symbol and its
+     offset.  */
+  asymbol **symbols;
+  bfd_vma *offsets;
+}
+oso_el;
+
+/* Vector of object files to be read after the executable.  */
+DEF_VEC_O (oso_el);
+static VEC (oso_el) *oso_vector;
+
+/*  Add a new OSO to the vector.  */
+static void
+macho_add_oso (const asymbol *oso_sym, int nbr_sections,
+	       asymbol **symbols, bfd_vma *offsets)
+{
+  oso_el el;
+
+  el.name = oso_sym->name;
+  el.mtime = oso_sym->value;
+  el.num_sections = nbr_sections;
+  el.symbols = symbols;
+  el.offsets = offsets;
+  VEC_safe_push (oso_el, oso_vector, &el);
+}
+
+/* Build the minimal symbol table from SYMBOL_TABLE of length
+   NUMBER_OF_SYMBOLS for OBJFILE.
+   Read OSO files at the end.  */
+static void
+macho_symtab_read (struct objfile *objfile,
+		   long number_of_symbols, asymbol **symbol_table)
+{
+  struct gdbarch *gdbarch = get_objfile_arch (objfile);
+  long storage_needed;
+  asymbol *sym;
+  long i, j;
+  CORE_ADDR offset;
+  enum minimal_symbol_type ms_type;
+  unsigned int nbr_sections = bfd_count_sections (objfile->obfd);
+  asymbol **first_symbol = NULL;
+  bfd_vma *first_offset = NULL;
+  const asymbol *oso_file = NULL;
+
+  for (i = 0; i < number_of_symbols; i++)
+    {
+      sym = symbol_table[i];
+      offset = ANOFFSET (objfile->section_offsets, sym->section->index);
+
+      if (sym->flags & BSF_DEBUGGING)
+	{
+	  unsigned char type = BFD_MACH_O_SYM_NTYPE(sym);
+	  bfd_vma addr;
+
+	  switch (type)
+	    {
+	    case N_SO:
+	      if ((sym->name == NULL || sym->name[0] == 0)
+		  && oso_file != NULL)
+		{
+		  macho_add_oso (oso_file, nbr_sections,
+				 first_symbol, first_offset);
+		  first_symbol = NULL;
+		  first_offset = NULL;
+		  oso_file = NULL;
+		}
+	      break;
+	    case N_FUN:
+	    case N_STSYM:
+	      if (sym->name == NULL || sym->name[0] == '\0')
+		break;
+	      /* Fall through.  */
+	    case N_BNSYM:
+	      gdb_assert (oso_file != NULL);
+	      addr = sym->value 
+		+ bfd_get_section_vma (sym->section->bfd, sym->section);
+	      if (addr != 0
+		  && first_symbol[sym->section->index] == NULL)
+		{
+		  first_symbol[sym->section->index] = sym;
+		  first_offset[sym->section->index] = addr + offset;
+		}
+	      break;
+	    case N_GSYM:
+	      gdb_assert (oso_file != NULL);
+	      if (first_symbol[sym->section->index] == NULL)
+		first_symbol[sym->section->index] = sym;
+	      break;
+	    case N_OSO:
+	      gdb_assert (oso_file == NULL);
+	      first_symbol = (asymbol **)xmalloc (nbr_sections
+						  * sizeof (asymbol *));
+	      first_offset = (bfd_vma *)xmalloc (nbr_sections
+						 * sizeof (bfd_vma));
+	      for (j = 0; j < nbr_sections; j++)
+		first_symbol[j] = NULL;
+	      oso_file = sym;
+	      break;
+	    }
+	  continue;
+	}
+
+      if (sym->name == NULL || *sym->name == '\0')
+	{
+	  /* Skip names that don't exist (shouldn't happen), or names
+	     that are null strings (may happen). */
+	  continue;
+	}
+
+      if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
+	{
+	  struct minimal_symbol *msym;
+	  CORE_ADDR symaddr;
+
+	  /* Bfd symbols are section relative. */
+	  symaddr = sym->value + sym->section->vma;
+
+	  /* Select global/local/weak symbols.  Note that bfd puts abs
+	     symbols in their own section, so all symbols we are
+	     interested in will have a section. */
+	  /* Relocate all non-absolute and non-TLS symbols by the
+	     section offset.  */
+	  if (sym->section != &bfd_abs_section
+	      && !(sym->section->flags & SEC_THREAD_LOCAL))
+	    symaddr += offset;
+
+	  if (sym->section == &bfd_abs_section)
+	    ms_type = mst_abs;
+	  else if (sym->section->flags & SEC_CODE)
+	    {
+	      if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
+		ms_type = mst_text;
+	      else
+		ms_type = mst_file_text;
+	    }
+	  else if (sym->section->flags & SEC_ALLOC)
+	    {
+	      if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
+		{
+		  if (sym->section->flags & SEC_LOAD)
+		    ms_type = mst_data;
+		  else
+		    ms_type = mst_bss;
+		}
+	      else if (sym->flags & BSF_LOCAL)
+		{
+		  /* Not a special stabs-in-elf symbol, do regular
+		     symbol processing.  */
+		  if (sym->section->flags & SEC_LOAD)
+		    ms_type = mst_file_data;
+		  else
+		    ms_type = mst_file_bss;
+		}
+	      else
+		ms_type = mst_unknown;
+	    }
+	  else
+	    continue;	/* Skip this symbol. */
+
+	  gdb_assert (sym->section->index < nbr_sections);
+	  if (oso_file != NULL
+	      && first_symbol[sym->section->index] == NULL)
+	    {
+	      first_symbol[sym->section->index] = sym;
+	      first_offset[sym->section->index] = symaddr;
+	    }
+
+	  msym = prim_record_minimal_symbol_and_info
+	    (sym->name, symaddr, ms_type, sym->section->index,
+	     sym->section, objfile);
+	}
+    }
+
+  if (oso_file != NULL)
+    macho_add_oso (oso_file, nbr_sections, first_symbol, first_offset);
+}
+
+/* If NAME describes an archive member (ie: ARCHIVE '(' MEMBER ')'),
+   returns the length of the archive name.
+   Returns -1 otherwise.  */
+static int
+get_archive_prefix_len (const char *name)
+{
+  char *lparen;
+  int name_len = strlen (name);
+
+  if (name_len == 0 || name[name_len - 1] != ')')
+    return -1;
+  
+  lparen = strrchr (name, '(');
+  if (lparen == NULL || lparen == name)
+    return -1;
+  return lparen - name;
+}
+
+/* Read symbols from the vector of oso files.  */
+static void
+macho_oso_symfile (struct objfile *main_objfile)
+{
+  int ix;
+  VEC (oso_el) *vec;
+  oso_el *oso;
+  char leading_char;
+
+  /* TODO: Sort them, group library search.  */
+
+  vec = oso_vector;
+  oso_vector = NULL;
+  
+  leading_char = bfd_get_symbol_leading_char (main_objfile->obfd);
+
+  for (ix = 0; VEC_iterate (oso_el, vec, ix, oso); ix++)
+    {
+      struct section_addr_info *addrs;
+      int pfx_len;
+      int len;
+      int i;
+      oso_el el;
+      
+      if (mach_o_debug_level > 0)
+	printf_unfiltered (_("Loading symbols from oso: %s\n"), oso->name);
+
+      /* Compute addr length.  */
+      len = 0;
+      for (i = 0; i < oso->num_sections; i++)
+	if (oso->symbols[i] != NULL)
+	  len++;
+
+      addrs = alloc_section_addr_info (len);
+
+      len = 0;
+      for (i = 0; i < oso->num_sections; i++)
+	if (oso->symbols[i] != NULL)
+	  {
+	    if (oso->offsets[i])
+	      addrs->other[len].addr = oso->offsets[i];
+	    else
+	      {
+		struct minimal_symbol *msym;
+		const char *name = oso->symbols[i]->name;
+
+		if (name[0] == leading_char)
+		  ++name;
+
+		if (mach_o_debug_level > 3)
+		  printf_unfiltered (_("resolv sec %s with %s\n"),
+				     oso->symbols[i]->section->name,
+				     oso->symbols[i]->name);
+		msym = lookup_minimal_symbol (name, NULL, main_objfile);
+		if (msym == NULL)
+		  {
+		    warning (_("can't find symbol '%s' in minsymtab"),
+			     oso->symbols[i]->name);
+		    addrs->other[len].addr = 0;
+		  }
+		else
+		  addrs->other[len].addr = SYMBOL_VALUE_ADDRESS (msym);
+	      }
+	    addrs->other[len].name = (char *)oso->symbols[i]->section->name;
+	    len++;
+	  }
+      
+      if (mach_o_debug_level > 1)
+	{
+	  int j;
+	  for (j = 0; j < addrs->num_sections; j++)
+	    printf_unfiltered
+	      (_("  %s: %s\n"),
+	       core_addr_to_string (addrs->other[j].addr),
+	       addrs->other[j].name);
+	}
+      
+      /* Check if this is a library name.  */
+      pfx_len = get_archive_prefix_len (oso->name);
+      if (pfx_len > 0)
+	{
+	  bfd *archive_bfd;
+	  bfd *member_bfd;
+	  char *archive_name = (char *) alloca (pfx_len + 1);
+	  int member_len;
+
+	  member_len = strlen (oso->name + pfx_len + 1) - 1;
+	  memcpy (archive_name, oso->name, pfx_len);
+	  archive_name[pfx_len] = '\0';
+
+	  /* Open the archive and check the format.  */
+	  archive_bfd = bfd_openr (archive_name, gnutarget);
+	  if (archive_bfd == NULL)
+	    {
+	      warning (_("Could not open OSO archive file \"%s\""),
+		       archive_name);
+	      continue;
+	    }
+	  if (!bfd_check_format (archive_bfd, bfd_archive))
+	    {
+	      warning (_("OSO archive file \"%s\" not an archive."),
+		       archive_name);
+	      bfd_close (archive_bfd);
+	      continue;
+	    }
+	  member_bfd = bfd_openr_next_archived_file (archive_bfd, NULL);
+	  
+	  if (member_bfd == NULL)
+	    {
+	      warning (_("Could not read archive members out of "
+			 "OSO archive \"%s\""), archive_name);
+	      bfd_close (archive_bfd);
+	      continue;
+	    }
+	  
+	  while (member_bfd != NULL)
+	    {
+	      bfd *prev = member_bfd;
+	      const char *member_name = member_bfd->filename;
+	      if (strlen (member_name) == member_len
+		  && !memcmp (member_name, oso->name + pfx_len + 1, member_len))
+		break;
+	      member_bfd = bfd_openr_next_archived_file
+		(archive_bfd, member_bfd);
+	      bfd_close (prev);
+	    }
+	  if (member_bfd == NULL)
+	    {
+	      warning (_("Could not find specified archive member "
+			 "for OSO name \"%s\""), oso->name);
+	      bfd_close (archive_bfd);
+	      continue;
+	    }
+	  
+	  bfd_set_cacheable (member_bfd, 1);
+  
+	  if (!bfd_check_format (member_bfd, bfd_object))
+	    {
+	      warning (_("`%s': can't read symbols: %s."), oso->name,
+		       bfd_errmsg (bfd_get_error ()));
+	      bfd_close (member_bfd);
+	    }
+	    else
+	      symbol_file_add_from_bfd (member_bfd, 0, addrs, 0, 0);
+	}
+      else
+	{
+	  bfd *abfd;
+
+	  abfd = bfd_openr (oso->name, gnutarget);
+	  if (!abfd)
+	    {
+	      warning (_("`%s': can't open to read symbols: %s."), oso->name,
+		       bfd_errmsg (bfd_get_error ()));
+	      continue;
+	    }
+	  bfd_set_cacheable (abfd, 1);
+  
+	  if (!bfd_check_format (abfd, bfd_object))
+	    {
+	      bfd_close (abfd);
+	      warning (_("`%s': can't read symbols: %s."), oso->name,
+		       bfd_errmsg (bfd_get_error ()));
+	      continue;
+	    }
+  
+	  symbol_file_add_from_bfd (abfd, 0, addrs, 0, 0);
+	}
+      xfree (oso->symbols);
+      xfree (oso->offsets);
+    }
+  VEC_free (oso_el, vec);
+}
+
+/* DSYM (debug symbols) files contain the debug info of an executable.
+   This is a separate file created by dsymutil(1) and is similar to debug
+   link feature on ELF.
+   DSYM files are located in a subdirectory.  Append DSYM_SUFFIX to the
+   executable name and the executable base name to get the DSYM file name.  */
+#define DSYM_SUFFIX ".dSYM/Contents/Resources/DWARF/"
+
+/* Check if a dsym file exists for OBJFILE.  If so, returns a bfd for it.
+   Return NULL if no valid dsym file is found.  */
+static bfd *
+macho_check_dsym (struct objfile *objfile)
+{
+  size_t name_len = strlen (objfile->name);
+  size_t dsym_len = strlen (DSYM_SUFFIX);
+  const char *base_name = lbasename (objfile->name);
+  size_t base_len = strlen (base_name);
+  char *dsym_filename = alloca (name_len + dsym_len + base_len + 1);
+  bfd *dsym_bfd;
+  asection *sect;
+  bfd_byte main_uuid[16];
+  bfd_byte dsym_uuid[16];
+
+  strcpy (dsym_filename, objfile->name);
+  strcpy (dsym_filename + name_len, DSYM_SUFFIX);
+  strcpy (dsym_filename + name_len + dsym_len, base_name);
+
+  if (access (dsym_filename, R_OK) != 0)
+    return NULL;
+
+  sect = bfd_get_section_by_name (objfile->obfd, "LC_UUID");
+  if (sect == NULL)
+    {
+      warning (_("can't find UUID in %s"), objfile->name);
+      return NULL;
+    }
+  if (!bfd_get_section_contents (objfile->obfd, sect, main_uuid,
+				 0, sizeof (main_uuid)))
+    {
+      warning (_("can't read UUID in %s"), objfile->name);
+      return NULL;
+    }
+
+  dsym_filename = xstrdup (dsym_filename);
+  dsym_bfd = bfd_openr (dsym_filename, gnutarget);
+  if (dsym_bfd == NULL)
+    {
+      warning (_("can't open dsym file %s"), dsym_filename);
+      xfree (dsym_filename);
+      return NULL;
+    }
+
+  if (!bfd_check_format (dsym_bfd, bfd_object))
+    {
+      bfd_close (dsym_bfd);
+      warning (_("bad dsym file format: %s"), bfd_errmsg (bfd_get_error ()));
+      xfree (dsym_filename);
+      return NULL;
+    }
+
+  sect = bfd_get_section_by_name (dsym_bfd, "LC_UUID");
+  if (sect == NULL)
+    {
+      warning (_("can't find UUID in %s"), dsym_filename);
+      bfd_close (dsym_bfd);
+      xfree (dsym_filename);
+      return NULL;
+    }
+  if (!bfd_get_section_contents (dsym_bfd, sect, dsym_uuid,
+				 0, sizeof (dsym_uuid)))
+    {
+      warning (_("can't read UUID in %s"), dsym_filename);
+      bfd_close (dsym_bfd);
+      xfree (dsym_filename);
+      return NULL;
+    }
+  if (memcmp (dsym_uuid, main_uuid, sizeof (main_uuid)))
+    {
+      warning (_("dsym file UUID doesn't match the one in %s"), objfile->name);
+      bfd_close (dsym_bfd);
+      xfree (dsym_filename);
+      return NULL;
+    }
+  return dsym_bfd;
+
+}
+
+static void
+macho_symfile_read (struct objfile *objfile, int mainline)
+{
+  bfd *abfd = objfile->obfd;
+  struct cleanup *back_to;
+  CORE_ADDR offset;
+  long storage_needed;
+  bfd *dsym_bfd;
+
+  init_minimal_symbol_collection ();
+  back_to = make_cleanup_discard_minimal_symbols ();
+
+  /* Get symbols from the symbol table only if the file is an executable.
+     The symbol table of object files is not relocated and is expected to
+     be in the executable.  */
+  if (bfd_get_file_flags (abfd) & EXEC_P)
+    {
+      /* Process the normal symbol table first.  */
+      storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
+      if (storage_needed < 0)
+	error (_("Can't read symbols from %s: %s"),
+	       bfd_get_filename (objfile->obfd),
+	       bfd_errmsg (bfd_get_error ()));
+
+      if (storage_needed > 0)
+	{
+	  asymbol **symbol_table;
+	  long symcount;
+
+	  symbol_table = (asymbol **) xmalloc (storage_needed);
+	  make_cleanup (xfree, symbol_table);
+	  symcount = bfd_canonicalize_symtab (objfile->obfd, symbol_table);
+	  
+	  if (symcount < 0)
+	    error (_("Can't read symbols from %s: %s"),
+		   bfd_get_filename (objfile->obfd),
+		   bfd_errmsg (bfd_get_error ()));
+	  
+	  macho_symtab_read (objfile, symcount, symbol_table);
+	}
+      
+      install_minimal_symbols (objfile);
+
+      /* Check for DSYM file.  */
+      dsym_bfd = macho_check_dsym (objfile);
+      if (dsym_bfd != NULL)
+	{
+	  int ix;
+	  oso_el *oso;
+
+	  if (mach_o_debug_level > 0)
+	    printf_unfiltered (_("dsym file found\n"));
+
+	  /* Remove oso.  They won't be used.  */
+	  for (ix = 0; VEC_iterate (oso_el, oso_vector, ix, oso); ix++)
+	    {
+	      xfree (oso->symbols);
+	      xfree (oso->offsets);
+	    }
+	  VEC_free (oso_el, oso_vector);
+	  oso_vector = NULL;
+
+	  /* Now recurse: read dwarf from dsym.  */
+	  symbol_file_add_from_bfd (dsym_bfd, 0, NULL, 0, 0);
+      
+	  /* Don't try to read dwarf2 from main file.  */
+	  return;
+	}
+    }
+
+  if (dwarf2_has_info (objfile))
+    {
+      /* DWARF 2 sections */
+      dwarf2_build_psymtabs (objfile, mainline);
+    }
+
+  /* FIXME: kettenis/20030504: This still needs to be integrated with
+     dwarf2read.c in a better way.  */
+  dwarf2_build_frame_info (objfile);
+
+  /* Then the oso.  */
+  if (oso_vector != NULL)
+    macho_oso_symfile (objfile);
+}
+
+static void
+macho_symfile_finish (struct objfile *objfile)
+{
+}
+
+static void
+macho_symfile_offsets (struct objfile *objfile,
+                       struct section_addr_info *addrs)
+{
+  unsigned int i;
+  unsigned int num_sections;
+  struct obj_section *osect;
+
+  /* Allocate section_offsets.  */
+  objfile->num_sections = bfd_count_sections (objfile->obfd);
+  objfile->section_offsets = (struct section_offsets *)
+    obstack_alloc (&objfile->objfile_obstack,
+                   SIZEOF_N_SECTION_OFFSETS (objfile->num_sections));
+  memset (objfile->section_offsets, 0,
+          SIZEOF_N_SECTION_OFFSETS (objfile->num_sections));
+
+  /* This code is run when we first add the objfile with
+     symfile_add_with_addrs_or_offsets, when "addrs" not "offsets" are
+     passed in.  The place in symfile.c where the addrs are applied
+     depends on the addrs having section names.  But in the dyld code
+     we build an anonymous array of addrs, so that code is a no-op.
+     Because of that, we have to apply the addrs to the sections here.
+     N.B. if an objfile slides after we've already created it, then it
+     goes through objfile_relocate.  */
+
+  for (i = 0; i < addrs->num_sections; i++)
+    {
+      if (addrs->other[i].name == NULL)
+	continue;
+
+      ALL_OBJFILE_OSECTIONS (objfile, osect)
+	{
+	  const char *bfd_sect_name = osect->the_bfd_section->name;
+
+	  if (strcmp (bfd_sect_name, addrs->other[i].name) == 0)
+	    {
+	      obj_section_offset (osect) = addrs->other[i].addr;
+	      break;
+	    }
+	}
+    }
+
+  objfile->sect_index_text = 0;
+
+  ALL_OBJFILE_OSECTIONS (objfile, osect)
+    {
+      const char *bfd_sect_name = osect->the_bfd_section->name;
+      int sect_index = osect->the_bfd_section->index;
+
+      if (strcmp (bfd_sect_name, "LC_SEGMENT.__TEXT") == 0)
+	objfile->sect_index_text = sect_index;
+      else if (strcmp (bfd_sect_name, "LC_SEGMENT.__TEXT.__text") == 0)
+	objfile->sect_index_text = sect_index;
+    }
+}
+
+static struct sym_fns macho_sym_fns = {
+  bfd_target_mach_o_flavour,
+
+  macho_new_init,               /* sym_new_init: init anything gbl to entire symtab */
+  macho_symfile_init,           /* sym_init: read initial info, setup for sym_read() */
+  macho_symfile_read,           /* sym_read: read a symbol file into symtab */
+  macho_symfile_finish,         /* sym_finish: finished with file, cleanup */
+  macho_symfile_offsets,        /* sym_offsets:  xlate external to internal form */
+  NULL                          /* next: pointer to next struct sym_fns */
+};
+
+void
+_initialize_machoread ()
+{
+  add_symtab_fns (&macho_sym_fns);
+
+  add_setshow_zinteger_cmd ("mach-o", class_obscure,
+			    &mach_o_debug_level, _("\
+Set if printing Mach-O symbols processing."), _("\
+Show if printing Mach-O symbols processing."), NULL,
+			    NULL, NULL,
+			    &setdebuglist, &showdebuglist);
+}
diff --git a/gdb/osabi.c b/gdb/osabi.c
index 64f091002f7..988e3887282 100644
--- a/gdb/osabi.c
+++ b/gdb/osabi.c
@@ -73,6 +73,7 @@ static const char * const gdb_osabi_names[] =
   "Cygwin",
   "AIX",
   "DICOS",
+  "Darwin",
 
   "<invalid>"
 };