Index: b/src/gcc/ada/s-osinte-kfreebsd-gnu.adb
===================================================================
--- /dev/null
+++ b/src/gcc/ada/s-osinte-kfreebsd-gnu.adb
@@ -0,0 +1,158 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
+--                                                                          --
+--                   S Y S T E M . O S _ I N T E R F A C E                  --
+--                                                                          --
+--                                   B o d y                                --
+--                                                                          --
+--             Copyright (C) 1991-1994, Florida State University            --
+--                     Copyright (C) 1995-2006, AdaCore                     --
+--                                                                          --
+-- GNARL is free software; you can  redistribute it  and/or modify it under --
+-- terms of the  GNU General Public License as published  by the Free Soft- --
+-- ware  Foundation;  either version 2,  or (at your option) any later ver- --
+-- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
+-- OUT 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  distributed with GNARL; see file COPYING.  If not, write --
+-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
+-- Boston, MA 02110-1301, USA.                                              --
+--                                                                          --
+-- As a special exception,  if other files  instantiate  generics from this --
+-- unit, or you link  this unit with other files  to produce an executable, --
+-- this  unit  does not  by itself 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 Public License.                                      --
+--                                                                          --
+-- GNARL was developed by the GNARL team at Florida State University.       --
+-- Extensive contributions were provided by Ada Core Technologies, Inc.     --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This is the GNU/kFreeBSD version of this package.
+
+pragma Polling (Off);
+--  Turn off polling, we do not want ATC polling to take place during
+--  tasking operations. It causes infinite loops and other problems.
+
+--  This package encapsulates all direct interfaces to OS services
+--  that are needed by children of System.
+
+package body System.OS_Interface is
+
+   --------------------
+   -- Get_Stack_Base --
+   --------------------
+
+   function Get_Stack_Base (thread : pthread_t) return Address is
+      pragma Warnings (Off, thread);
+
+   begin
+      return Null_Address;
+   end Get_Stack_Base;
+
+   ------------------
+   -- pthread_init --
+   ------------------
+
+   procedure pthread_init is
+   begin
+      null;
+   end pthread_init;
+
+   -----------------------------------
+   -- pthread_mutexattr_setprotocol --
+   -----------------------------------
+
+   function pthread_mutexattr_setprotocol
+     (attr     : access pthread_mutexattr_t;
+      protocol : int) return int is
+      pragma Unreferenced (attr, protocol);
+   begin
+      return 0;
+   end pthread_mutexattr_setprotocol;
+
+   -----------------------------------
+   -- pthread_mutexattr_getprotocol --
+   -----------------------------------
+
+   function pthread_mutexattr_getprotocol
+     (attr     : access pthread_mutexattr_t;
+      protocol : access int) return int is
+      pragma Unreferenced (attr, protocol);
+   begin
+      return 0;
+   end pthread_mutexattr_getprotocol;
+
+   --------------------------------------
+   -- pthread_mutexattr_setprioceiling --
+   --------------------------------------
+
+   function pthread_mutexattr_setprioceiling
+     (attr     : access pthread_mutexattr_t;
+      prioceiling : int) return int is
+      pragma Unreferenced (attr, prioceiling);
+   begin
+      return 0;
+   end pthread_mutexattr_setprioceiling;
+
+   --------------------------------------
+   -- pthread_mutexattr_getprioceiling --
+   --------------------------------------
+
+   function pthread_mutexattr_getprioceiling
+     (attr     : access pthread_mutexattr_t;
+      prioceiling : access int) return int is
+      pragma Unreferenced (attr, prioceiling);
+   begin
+      return 0;
+   end pthread_mutexattr_getprioceiling;
+
+   -----------------
+   -- To_Duration --
+   -----------------
+
+   function To_Duration (TS : timespec) return Duration is
+   begin
+      return Duration (TS.tv_sec) + Duration (TS.tv_nsec) / 10#1#E9;
+   end To_Duration;
+
+   ------------------------
+   -- To_Target_Priority --
+   ------------------------
+
+   function To_Target_Priority
+     (Prio : System.Any_Priority) return Interfaces.C.int
+   is
+   begin
+      return Interfaces.C.int (Prio);
+   end To_Target_Priority;
+
+   -----------------
+   -- To_Timespec --
+   -----------------
+
+   function To_Timespec (D : Duration) return timespec is
+      S : time_t;
+      F : Duration;
+
+   begin
+      S := time_t (Long_Long_Integer (D));
+      F := D - Duration (S);
+
+      --  If F has negative value due to a round-up, adjust for positive F
+      --  value.
+
+      if F < 0.0 then
+         S := S - 1;
+         F := F + 1.0;
+      end if;
+
+      return timespec'(tv_sec => S,
+                       tv_nsec => long (Long_Long_Integer (F * 10#1#E9)));
+   end To_Timespec;
+
+end System.OS_Interface;
Index: b/src/gcc/ada/gcc-interface/Makefile.in
===================================================================
--- a/src/gcc/ada/gcc-interface/Makefile.in
+++ b/src/gcc/ada/gcc-interface/Makefile.in
@@ -1097,7 +1097,7 @@
   a-numaux.ads<a-numaux-x86.ads \
   s-inmaop.adb<s-inmaop-posix.adb \
   s-intman.adb<s-intman-posix.adb \
-  s-osinte.adb<s-osinte-posix.adb \
+  s-osinte.adb<s-osinte-kfreebsd-gnu.adb \
   s-osinte.ads<s-osinte-kfreebsd-gnu.ads \
   s-osprim.adb<s-osprim-posix.adb \
   s-taprop.adb<s-taprop-posix.adb \
@@ -1123,7 +1123,7 @@
   a-numaux.ads<a-numaux-x86.ads \
   s-inmaop.adb<s-inmaop-posix.adb \
   s-intman.adb<s-intman-posix.adb \
-  s-osinte.adb<s-osinte-posix.adb \
+  s-osinte.adb<s-osinte-kfreebsd-gnu.adb \
   s-osinte.ads<s-osinte-kfreebsd-gnu.ads \
   s-osprim.adb<s-osprim-posix.adb \
   s-taprop.adb<s-taprop-posix.adb \
@@ -1137,7 +1137,7 @@
     indepsw.adb<indepsw-gnu.adb
 
   EH_MECHANISM=-gcc
-  THREADSLIB = -lpthread
+  THREADSLIB = -lpthread -lrt
   GNATLIB_SHARED = gnatlib-shared-dual
   GMEM_LIB = gmemlib
   LIBRARY_VERSION := $(LIB_VERSION)
@@ -1165,7 +1165,7 @@
     indepsw.adb<indepsw-gnu.adb
 
   EH_MECHANISM=-gcc
-  THREADSLIB = -lpthread
+  THREADSLIB = -lpthread -lrt
   GNATLIB_SHARED = gnatlib-shared-dual
   GMEM_LIB = gmemlib
   LIBRARY_VERSION := $(LIB_VERSION)
Index: b/src/gcc/ada/s-osinte-kfreebsd-gnu.ads
===================================================================
--- a/src/gcc/ada/s-osinte-kfreebsd-gnu.ads
+++ b/src/gcc/ada/s-osinte-kfreebsd-gnu.ads
@@ -47,6 +47,7 @@
    pragma Preelaborate;
 
    pragma Linker_Options ("-lpthread");
+   pragma Linker_Options ("-lrt");
 
    subtype int            is Interfaces.C.int;
    subtype char           is Interfaces.C.char;
@@ -431,31 +432,25 @@
    PTHREAD_PRIO_PROTECT : constant := 2;
    PTHREAD_PRIO_INHERIT : constant := 1;
 
+   --  GNU/kFreeBSD does not support Thread Priority Protection or Thread
+   --  Priority Inheritance and lacks some pthread_mutexattr_* functions.
+   --  Replace them with dummy versions.
+
    function pthread_mutexattr_setprotocol
      (attr     : access pthread_mutexattr_t;
       protocol : int) return int;
-   pragma Import
-      (C, pthread_mutexattr_setprotocol, "pthread_mutexattr_setprotocol");
 
    function pthread_mutexattr_getprotocol
      (attr     : access pthread_mutexattr_t;
       protocol : access int) return int;
-   pragma Import
-     (C, pthread_mutexattr_getprotocol, "pthread_mutexattr_getprotocol");
 
    function pthread_mutexattr_setprioceiling
      (attr     : access pthread_mutexattr_t;
       prioceiling : int) return int;
-   pragma Import
-     (C, pthread_mutexattr_setprioceiling,
-      "pthread_mutexattr_setprioceiling");
 
    function pthread_mutexattr_getprioceiling
      (attr     : access pthread_mutexattr_t;
       prioceiling : access int) return int;
-   pragma Import
-     (C, pthread_mutexattr_getprioceiling,
-      "pthread_mutexattr_getprioceiling");
 
    type struct_sched_param is record
       sched_priority : int;  --  scheduling priority
