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diff --git a/gnu/usr.bin/gcc/objc/thr.c b/gnu/usr.bin/gcc/objc/thr.c
new file mode 100644
index 00000000000..f1c957aaa15
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+++ b/gnu/usr.bin/gcc/objc/thr.c
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+/* GNU Objective C Runtime Thread Interface
+   Copyright (C) 1996, 1997 Free Software Foundation, Inc.
+   Contributed by Galen C. Hunt (gchunt@cs.rochester.edu)
+
+This file is part of GNU CC.
+
+GNU CC 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, or (at your option) any later version.
+
+GNU CC 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
+GNU CC; see the file COPYING.  If not, write to the Free Software
+Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+/* As a special exception, if you link this library with files compiled with
+   GCC to produce an executable, this does not cause the resulting executable
+   to be covered by the GNU General Public License. This exception does not
+   however invalidate any other reasons why the executable file might be
+   covered by the GNU General Public License.  */
+
+#include <stdlib.h>
+#include "runtime.h"
+
+/* Global exit status. */
+int __objc_thread_exit_status = 0;
+
+/* Flag which lets us know if we ever became multi threaded */
+int __objc_is_multi_threaded = 0;
+
+/* The hook function called when the runtime becomes multi threaded */
+objc_thread_callback _objc_became_multi_threaded = NULL;
+
+/*
+  Use this to set the hook function that will be called when the 
+  runtime initially becomes multi threaded.
+  The hook function is only called once, meaning only when the 
+  2nd thread is spawned, not for each and every thread.
+
+  It returns the previous hook function or NULL if there is none.
+
+  A program outside of the runtime could set this to some function so
+  it can be informed; for example, the GNUstep Base Library sets it 
+  so it can implement the NSBecomingMultiThreaded notification.
+  */
+objc_thread_callback objc_set_thread_callback(objc_thread_callback func)
+{
+  objc_thread_callback temp = _objc_became_multi_threaded;
+  _objc_became_multi_threaded = func;
+  return temp;
+}
+
+/*
+  Private functions
+
+  These functions are utilized by the frontend, but they are not
+  considered part of the public interface.
+  */
+
+/*
+  First function called in a thread, starts everything else.
+
+  This function is passed to the backend by objc_thread_detach
+  as the starting function for a new thread.
+ */
+struct __objc_thread_start_state
+{
+  SEL selector;
+  id object;
+  id argument;
+};
+
+static volatile void
+__objc_thread_detach_function(struct __objc_thread_start_state *istate)
+{
+  /* Valid state? */
+  if (istate) {
+    id (*imp)(id,SEL,id);
+    SEL selector = istate->selector;
+    id object   = istate->object;
+    id argument = istate->argument;
+
+    /* Don't need anymore so free it */
+    objc_free(istate);
+
+    /* Clear out the thread local storage */
+    objc_thread_set_data(NULL);
+
+    /* Check to see if we just became multi threaded */
+    if (!__objc_is_multi_threaded)
+      {
+	__objc_is_multi_threaded = 1;
+
+	/* Call the hook function */
+	if (_objc_became_multi_threaded != NULL)
+	  (*_objc_became_multi_threaded)();
+      }
+
+    /* Call the method */
+    if ((imp = (id(*)(id, SEL, id))objc_msg_lookup(object, selector)))
+	(*imp)(object, selector, argument);
+    else
+      objc_error(object, OBJC_ERR_UNIMPLEMENTED,
+		 "objc_thread_detach called with bad selector.\n");
+  }
+  else
+    objc_error(nil, OBJC_ERR_BAD_STATE,
+	       "objc_thread_detach called with NULL state.\n");
+
+  /* Exit the thread */
+  objc_thread_exit();
+}
+
+/*
+  Frontend functions
+
+  These functions constitute the public interface to the Objective-C thread
+  and mutex functionality.
+  */
+
+/* Frontend thread functions */
+
+/*
+  Detach a new thread of execution and return its id.  Returns NULL if fails.
+  Thread is started by sending message with selector to object.  Message
+  takes a single argument.
+  */
+objc_thread_t
+objc_thread_detach(SEL selector, id object, id argument)
+{
+  struct __objc_thread_start_state *istate;
+  objc_thread_t        thread_id = NULL;
+
+  /* Allocate the state structure */
+  if (!(istate = (struct __objc_thread_start_state *)
+	objc_malloc(sizeof(*istate))))
+    return NULL;
+
+  /* Initialize the state structure */
+  istate->selector = selector;
+  istate->object = object;
+  istate->argument = argument;
+
+  /* lock access */
+  objc_mutex_lock(__objc_runtime_mutex);
+
+  /* Call the backend to spawn the thread */
+  if ((thread_id = __objc_thread_detach((void *)__objc_thread_detach_function,
+					istate)) == NULL)
+    {
+      /* failed! */
+      objc_mutex_unlock(__objc_runtime_mutex);
+      objc_free(istate);
+      return NULL;
+    }
+
+  /* Increment our thread counter */
+  __objc_runtime_threads_alive++;
+  objc_mutex_unlock(__objc_runtime_mutex);
+
+  return thread_id;
+}
+
+/* Set the current thread's priority. */
+int
+objc_thread_set_priority(int priority)
+{
+  /* Call the backend */
+  return __objc_thread_set_priority(priority);
+}
+
+/* Return the current thread's priority. */
+int
+objc_thread_get_priority(void)
+{
+  /* Call the backend */
+  return __objc_thread_get_priority();
+}
+
+/*
+  Yield our process time to another thread.  Any BUSY waiting that is done
+  by a thread should use this function to make sure that other threads can
+  make progress even on a lazy uniprocessor system.
+  */
+void
+objc_thread_yield(void)
+{
+  /* Call the backend */
+  __objc_thread_yield();
+}
+
+/*
+  Terminate the current tread.  Doesn't return.
+  Actually, if it failed returns -1.
+  */
+int
+objc_thread_exit(void)
+{
+  /* Decrement our counter of the number of threads alive */
+  objc_mutex_lock(__objc_runtime_mutex);
+  __objc_runtime_threads_alive--;
+  objc_mutex_unlock(__objc_runtime_mutex);
+
+  /* Call the backend to terminate the thread */
+  return __objc_thread_exit();
+}
+
+/*
+  Returns an integer value which uniquely describes a thread.  Must not be
+  NULL which is reserved as a marker for "no thread".
+  */
+objc_thread_t
+objc_thread_id(void)
+{
+  /* Call the backend */
+  return __objc_thread_id();
+}
+
+/*
+  Sets the thread's local storage pointer. 
+  Returns 0 if successful or -1 if failed.
+  */
+int
+objc_thread_set_data(void *value)
+{
+  /* Call the backend */
+  return __objc_thread_set_data(value);
+}
+
+/*
+  Returns the thread's local storage pointer.  Returns NULL on failure.
+  */
+void *
+objc_thread_get_data(void)
+{
+  /* Call the backend */
+  return __objc_thread_get_data();
+}
+
+/* Frontend mutex functions */
+
+/*
+  Allocate a mutex.  Return the mutex pointer if successful or NULL if the
+  allocation failed for any reason.
+  */
+objc_mutex_t
+objc_mutex_allocate(void)
+{
+  objc_mutex_t mutex;
+
+  /* Allocate the mutex structure */
+  if (!(mutex = (objc_mutex_t)objc_malloc(sizeof(struct objc_mutex))))
+    return NULL;
+
+  /* Call backend to create the mutex */
+  if (__objc_mutex_allocate(mutex))
+    {
+      /* failed! */
+      objc_free(mutex);
+      return NULL;
+    }
+
+  /* Initialize mutex */
+  mutex->owner = NULL;
+  mutex->depth = 0;
+  return mutex;
+}
+
+/*
+  Deallocate a mutex.  Note that this includes an implicit mutex_lock to
+  insure that no one else is using the lock.  It is legal to deallocate
+  a lock if we have a lock on it, but illegal to deallocate a lock held
+  by anyone else.
+  Returns the number of locks on the thread.  (1 for deallocate).
+  */
+int
+objc_mutex_deallocate(objc_mutex_t mutex)
+{
+  int depth;
+
+  /* Valid mutex? */
+  if (!mutex)
+    return -1;
+
+  /* Acquire lock on mutex */
+  depth = objc_mutex_lock(mutex);
+
+  /* Call backend to destroy mutex */
+  if (__objc_mutex_deallocate(mutex))
+    return -1;
+
+  /* Free the mutex structure */
+  objc_free(mutex);
+
+  /* Return last depth */
+  return depth;
+}
+
+/*
+  Grab a lock on a mutex.  If this thread already has a lock on this mutex
+  then we increment the lock count.  If another thread has a lock on the 
+  mutex we block and wait for the thread to release the lock.
+  Returns the lock count on the mutex held by this thread.
+  */
+int
+objc_mutex_lock(objc_mutex_t mutex)
+{
+  objc_thread_t thread_id;
+  int status;
+
+  /* Valid mutex? */
+  if (!mutex)
+    return -1;
+
+  /* If we already own the lock then increment depth */
+  thread_id = objc_thread_id();
+  if (mutex->owner == thread_id)
+    return ++mutex->depth;
+
+  /* Call the backend to lock the mutex */
+  status = __objc_mutex_lock(mutex);
+
+  /* Failed? */
+  if (status)
+    return status;
+
+  /* Successfully locked the thread */
+  mutex->owner = thread_id;
+  return mutex->depth = 1;
+}
+
+/*
+  Try to grab a lock on a mutex.  If this thread already has a lock on
+  this mutex then we increment the lock count and return it.  If another
+  thread has a lock on the mutex returns -1.
+  */
+int
+objc_mutex_trylock(objc_mutex_t mutex)
+{
+  objc_thread_t thread_id;
+  int status;
+
+  /* Valid mutex? */
+  if (!mutex)
+    return -1;
+
+  /* If we already own the lock then increment depth */ 
+  thread_id = objc_thread_id();
+  if (mutex->owner == thread_id)
+    return ++mutex->depth;
+    
+  /* Call the backend to try to lock the mutex */
+  status = __objc_mutex_trylock(mutex);
+
+  /* Failed? */
+  if (status)
+    return status;
+
+  /* Successfully locked the thread */
+  mutex->owner = thread_id;
+  return mutex->depth = 1;
+}
+
+/* 
+  Unlocks the mutex by one level.
+  Decrements the lock count on this mutex by one.
+  If the lock count reaches zero, release the lock on the mutex.
+  Returns the lock count on the mutex.
+  It is an error to attempt to unlock a mutex which this thread 
+  doesn't hold in which case return -1 and the mutex is unaffected.
+  */
+int
+objc_mutex_unlock(objc_mutex_t mutex)
+{
+  objc_thread_t thread_id;
+  int status;
+
+  /* Valid mutex? */
+  if (!mutex)
+    return -1;
+
+  /* If another thread owns the lock then abort */
+  thread_id = objc_thread_id();
+  if (mutex->owner != thread_id)
+    return -1;
+
+  /* Decrement depth and return */
+  if (mutex->depth > 1)
+    return --mutex->depth;
+
+  /* Depth down to zero so we are no longer the owner */
+  mutex->depth = 0;
+  mutex->owner = NULL;
+
+  /* Have the backend unlock the mutex */
+  status = __objc_mutex_unlock(mutex);
+
+  /* Failed? */
+  if (status)
+    return status;
+
+  return 0;
+}
+
+/* Frontend condition mutex functions */
+
+/*
+  Allocate a condition.  Return the condition pointer if successful or NULL
+  if the allocation failed for any reason.
+  */
+objc_condition_t 
+objc_condition_allocate(void)
+{
+  objc_condition_t condition;
+    
+  /* Allocate the condition mutex structure */
+  if (!(condition = 
+	(objc_condition_t)objc_malloc(sizeof(struct objc_condition))))
+    return NULL;
+
+  /* Call the backend to create the condition mutex */
+  if (__objc_condition_allocate(condition))
+    {
+      /* failed! */
+      objc_free(condition);
+      return NULL;
+    }
+
+  /* Success! */
+  return condition;
+}
+
+/*
+  Deallocate a condition. Note that this includes an implicit 
+  condition_broadcast to insure that waiting threads have the opportunity
+  to wake.  It is legal to dealloc a condition only if no other
+  thread is/will be using it. Here we do NOT check for other threads
+  waiting but just wake them up.
+  */
+int
+objc_condition_deallocate(objc_condition_t condition)
+{
+  /* Broadcast the condition */
+  if (objc_condition_broadcast(condition))
+    return -1;
+
+  /* Call the backend to destroy */
+  if (__objc_condition_deallocate(condition))
+    return -1;
+
+  /* Free the condition mutex structure */
+  objc_free(condition);
+
+  return 0;
+}
+
+/*
+  Wait on the condition unlocking the mutex until objc_condition_signal()
+  or objc_condition_broadcast() are called for the same condition. The
+  given mutex *must* have the depth set to 1 so that it can be unlocked
+  here, so that someone else can lock it and signal/broadcast the condition.
+  The mutex is used to lock access to the shared data that make up the
+  "condition" predicate.
+  */
+int
+objc_condition_wait(objc_condition_t condition, objc_mutex_t mutex)
+{
+  objc_thread_t thread_id;
+
+  /* Valid arguments? */
+  if (!mutex || !condition)
+    return -1;
+
+  /* Make sure we are owner of mutex */
+  thread_id = objc_thread_id();
+  if (mutex->owner != thread_id)
+    return -1;
+
+  /* Cannot be locked more than once */
+  if (mutex->depth > 1)
+    return -1;
+
+  /* Virtually unlock the mutex */
+  mutex->depth = 0;
+  mutex->owner = (objc_thread_t)NULL;
+
+  /* Call the backend to wait */
+  __objc_condition_wait(condition, mutex);
+
+  /* Make ourselves owner of the mutex */
+  mutex->owner = thread_id;
+  mutex->depth = 1;
+
+  return 0;
+}
+
+/*
+  Wake up all threads waiting on this condition. It is recommended that 
+  the called would lock the same mutex as the threads in objc_condition_wait
+  before changing the "condition predicate" and make this call and unlock it
+  right away after this call.
+  */
+int
+objc_condition_broadcast(objc_condition_t condition)
+{
+  /* Valid condition mutex? */
+  if (!condition)
+    return -1;
+
+  return __objc_condition_broadcast(condition);
+}
+
+/*
+  Wake up one thread waiting on this condition. It is recommended that 
+  the called would lock the same mutex as the threads in objc_condition_wait
+  before changing the "condition predicate" and make this call and unlock it
+  right away after this call.
+  */
+int
+objc_condition_signal(objc_condition_t condition)
+{
+  /* Valid condition mutex? */
+  if (!condition)
+    return -1;
+
+  return __objc_condition_signal(condition);
+}
+
+/* End of File */