diff --git a/csu/libc-tls.c b/csu/libc-tls.c
index 00138eb43a..af81cba12c 100644
--- a/csu/libc-tls.c
+++ b/csu/libc-tls.c
@@ -195,6 +195,7 @@ __libc_setup_tls (void)
 #endif
   if (__builtin_expect (lossage != NULL, 0))
     _startup_fatal (lossage);
+  __dl_inittcb ();
 
   /* Update the executable's link map with enough information to make
      the TLS routines happy.  */
diff --git a/elf/Makefile b/elf/Makefile
index 8563555079..66ce2953a4 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -30,7 +30,7 @@ routines	= $(all-dl-routines) dl-support dl-iteratephdr \
 # profiled libraries.
 dl-routines	= $(addprefix dl-,load lookup object reloc deps hwcaps \
 				  runtime init fini debug misc \
-				  version profile tls origin scope \
+				  version profile tls inittcb origin scope \
 				  execstack caller open close trampoline \
 				  exception sort-maps)
 ifeq (yes,$(use-ldconfig))
diff --git a/elf/dl-inittcb.c b/elf/dl-inittcb.c
new file mode 100644
index 0000000000..5a70e9775d
--- /dev/null
+++ b/elf/dl-inittcb.c
@@ -0,0 +1,22 @@
+/* Initialize TCB contents.  Generic version.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+void
+__dl_inittcb (void)
+{
+}
diff --git a/elf/rtld.c b/elf/rtld.c
index cfd3729b8e..214e2312fa 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -740,6 +740,7 @@ cannot allocate TLS data structures for initial thread\n");
   const char *lossage = TLS_INIT_TP (tcbp);
   if (__glibc_unlikely (lossage != NULL))
     _dl_fatal_printf ("cannot set up thread-local storage: %s\n", lossage);
+  __dl_inittcb ();
   tls_init_tp_called = true;
 
   return tcbp;
diff --git a/manual/threads.texi b/manual/threads.texi
index 769d974d50..6c62ff3da0 100644
--- a/manual/threads.texi
+++ b/manual/threads.texi
@@ -80,6 +80,7 @@ the standard.
 @menu
 * Default Thread Attributes::             Setting default attributes for
 					  threads in a process.
+* Identifying Threads::                   Unique identifiers for threads.
 @end menu
 
 @node Default Thread Attributes
@@ -124,6 +125,29 @@ The system does not have sufficient memory.
 @end table
 @end deftypefun
 
+@node Identifying Threads
+@subsection Unique identifiers for threads
+
+@Theglibc{} provides a non-standard function to obtain a unique thread
+identifier.
+
+@deftypefun uint64_t pthread_thread_number_np (pthread_t @var{thread})
+@standards{GNU, pthread.h}
+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
+
+This function returns a number that uniquely identifies @var{thread}
+among all past, current, and future running threads.  This number does
+not change during the life-time of the thread.  Once returned by this
+function, a number will not be reused after the thread terminates.
+
+The returned number is only unique with regards to the current process.
+It may be shared by subprocesses and other processes in the system.
+
+The initial (main) thread has number 1.  Thread numbers are not
+necessarily assigned in a consecutive fashion.  They bear no
+relationship to process IDs or thread IDs assigned by the kernel.
+@end deftypefun
+
 @c FIXME these are undocumented:
 @c pthread_atfork
 @c pthread_attr_destroy
diff --git a/nptl/Makefile b/nptl/Makefile
index ae388d1112..087fb6a8b5 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -30,7 +30,7 @@ install-lib-ldscripts := libpthread.so
 
 routines = alloca_cutoff forward libc-lowlevellock libc-cancellation \
 	   libc-cleanup libc_pthread_init libc_multiple_threads \
-	   register-atfork unregister-atfork pthread_self
+	   register-atfork unregister-atfork pthread_self thread_number
 shared-only-routines = forward
 
 # We need to provide certain routines for compatibility with existing
@@ -302,7 +302,8 @@ tests = tst-attr1 tst-attr2 tst-attr3 tst-default-attr \
 			    c89 gnu89 c99 gnu99 c11 gnu11) \
 	tst-bad-schedattr \
 	tst-thread_local1 tst-mutex-errorcheck tst-robust10 \
-	tst-robust-fork tst-create-detached tst-memstream
+	tst-robust-fork tst-create-detached tst-memstream \
+	tst-thread_number-single tst-thread_number-multi \
 
 tests-internal := tst-rwlock19 tst-rwlock20 \
 		  tst-sem11 tst-sem12 tst-sem13 \
@@ -318,7 +319,9 @@ test-srcs = tst-oddstacklimit
 test-xfail-tst-once5 = yes
 
 # Files which must not be linked with libpthread.
-tests-nolibpthread = tst-unload
+tests-nolibpthread = tst-unload \
+  tst-thread_number-single \
+  tst-thread_number-single-static \
 
 gen-as-const-headers = pthread-errnos.sym \
 		       unwindbuf.sym \
@@ -433,9 +436,13 @@ link-libc-static := $(common-objpfx)libc.a $(static-gnulib) \
 tests-static += tst-locale1 tst-locale2 tst-stackguard1-static \
 		tst-cancel21-static tst-cancel24-static tst-cond8-static \
 		tst-mutex8-static tst-mutexpi8-static tst-sem11-static \
-		tst-sem12-static
+		tst-sem12-static tst-thread_number-single-static \
+		tst-thread_number-multi-static \
+
 tests += tst-cancel21-static tst-cancel24-static \
-	 tst-cond8-static
+  tst-cond8-static tst-thread_number-single-static \
+  tst-thread_number-multi-static \
+
 tests-internal += tst-sem11-static tst-sem12-static tst-stackguard1-static
 xtests-static += tst-setuid1-static
 
diff --git a/nptl/Versions b/nptl/Versions
index 0ae5def464..8b6c839408 100644
--- a/nptl/Versions
+++ b/nptl/Versions
@@ -28,6 +28,9 @@ libc {
     pthread_cond_wait; pthread_cond_signal;
     pthread_cond_broadcast; pthread_cond_timedwait;
   }
+  GLBIC_2.27 {
+    pthread_thread_number_np;
+  }
   GLIBC_PRIVATE {
     __libc_alloca_cutoff;
     # Internal libc interface to libpthread
diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c
index 1cc7893195..0e1cf3939e 100644
--- a/nptl/allocatestack.c
+++ b/nptl/allocatestack.c
@@ -413,16 +413,21 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
   assert (powerof2 (pagesize_m1 + 1));
   assert (TCB_ALIGNMENT >= STACK_ALIGN);
 
-  /* Get the stack size from the attribute if it is set.  Otherwise we
-     use the default we determined at start time.  */
-  if (attr->stacksize != 0)
-    size = attr->stacksize;
-  else
-    {
-      lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
+  uint64_t thread_number;
+  lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
+  {
+    /* Number 1 is reserved for the initial thread.  */
+    static uint64_t global_thread_number = 1;
+    thread_number = ++global_thread_number;
+
+    /* Get the stack size from the attribute if it is set.  Otherwise
+       we use the default we determined at start time.  */
+    if (attr->stacksize != 0)
+      size = attr->stacksize;
+    else
       size = __default_pthread_attr.stacksize;
-      lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
-    }
+  }
+  lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
 
   /* Get memory for the stack.  */
   if (__glibc_unlikely (attr->flags & ATTR_FLAG_STACKADDR))
@@ -758,6 +763,8 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
 #endif
   pd->robust_head.list = &pd->robust_head;
 
+  pd->number = thread_number;
+
   /* We place the thread descriptor at the end of the stack.  */
   *pdp = pd;
 
diff --git a/nptl/descr.h b/nptl/descr.h
index c83b17b674..49e266139e 100644
--- a/nptl/descr.h
+++ b/nptl/descr.h
@@ -395,6 +395,9 @@ struct pthread
   /* Resolver state.  */
   struct __res_state res;
 
+  /* Unique number assigned to this thread.  */
+  uint64_t number;
+
   /* This member must be last.  */
   char end_padding[];
 
diff --git a/nptl/thread_number.c b/nptl/thread_number.c
new file mode 100644
index 0000000000..a9fdaa508b
--- /dev/null
+++ b/nptl/thread_number.c
@@ -0,0 +1,26 @@
+/* Unique numbers for threads.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "pthreadP.h"
+
+__uint64_t
+pthread_thread_number_np (pthread_t threadid)
+{
+  struct pthread *pd = (struct pthread *) threadid;
+  return pd->number;
+}
diff --git a/nptl/tst-thread_number-multi-static.c b/nptl/tst-thread_number-multi-static.c
new file mode 100644
index 0000000000..658928cfd5
--- /dev/null
+++ b/nptl/tst-thread_number-multi-static.c
@@ -0,0 +1,19 @@
+/* Test unique numbers for threads, static multi-threaded version.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "tst-thread_number-multi.c"
diff --git a/nptl/tst-thread_number-multi.c b/nptl/tst-thread_number-multi.c
new file mode 100644
index 0000000000..e26f19e44a
--- /dev/null
+++ b/nptl/tst-thread_number-multi.c
@@ -0,0 +1,99 @@
+/* Test unique numbers for threads, non-static multi-threaded version.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <support/check.h>
+#include <support/namespace.h>
+#include <support/xthread.h>
+
+static void
+subprocess (void *closure)
+{
+  TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+}
+
+static void *
+subthread (void *closure)
+{
+  if (closure != NULL)
+    xpthread_barrier_wait (closure);
+  return NULL;
+}
+
+static int
+compare (const void *pleft, const void *pright)
+{
+  uint64_t left = *(const uint64_t *)pleft;
+  uint64_t right = *(const uint64_t *)pright;
+  if (left < right)
+    return -1;
+  if (left > right)
+    return 1;
+  return 0;
+}
+
+static int
+do_test (void)
+{
+  TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+  support_isolate_in_subprocess (subprocess, NULL);
+
+  /* Create thread_count threads, half of which are joined
+     immediately, have of which stay arround.  */
+  enum { thread_count = 10 };
+  pthread_barrier_t barrier;
+  xpthread_barrier_init (&barrier, NULL, thread_count / 2 + 1);
+  uint64_t ids[thread_count];
+  pthread_t threads[thread_count]; /* Only even-numbered entries are valid.  */
+  for (int i = 0; i < thread_count; ++i)
+    {
+      bool stay_around = (i % 2) == 0;
+      threads[i] = xpthread_create (NULL, subthread,
+                                    stay_around ? &barrier : NULL);
+      ids[i] = pthread_thread_number_np (threads[i]);
+      TEST_VERIFY (ids[i] != 1);
+      if (!stay_around)
+        xpthread_join (threads[i]);
+    }
+
+  /* Check that the IDs are all distinct.  */
+  qsort (ids, thread_count, sizeof (ids[0]), compare);
+  for (int i = 1; i < thread_count; ++i)
+    TEST_VERIFY (ids[i - 1] < ids[i]);
+
+  /* Main thread ID should remain at 1.  */
+  TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+  support_isolate_in_subprocess (subprocess, NULL);
+
+  /* Clean up.  */
+  xpthread_barrier_wait (&barrier);
+  for (int i = 0; i < thread_count; ++i)
+    if ((i % 2) == 0)
+      xpthread_join (threads[i]);
+
+  /* Main thread ID should still remain at 1.  */
+  TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+  support_isolate_in_subprocess (subprocess, NULL);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/nptl/tst-thread_number-single-static.c b/nptl/tst-thread_number-single-static.c
new file mode 100644
index 0000000000..5c21063c36
--- /dev/null
+++ b/nptl/tst-thread_number-single-static.c
@@ -0,0 +1,19 @@
+/* Test unique numbers for threads, static single-threaded version.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "tst-thread_number-single.c"
diff --git a/nptl/tst-thread_number-single.c b/nptl/tst-thread_number-single.c
new file mode 100644
index 0000000000..43497205c7
--- /dev/null
+++ b/nptl/tst-thread_number-single.c
@@ -0,0 +1,38 @@
+/* Test unique numbers for threads, non-static single-threaded version.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <support/check.h>
+#include <support/namespace.h>
+
+static void
+subprocess (void *closure)
+{
+  TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+}
+
+static int
+do_test (void)
+{
+  TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+  support_isolate_in_subprocess (subprocess, NULL);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index 7a65dc641c..99f2e58875 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -1056,6 +1056,10 @@ void __libc_setup_tls (void);
 void __pthread_initialize_minimal (void) weak_function;
 #endif
 
+/* Initialize the already-existing TCB for the main thread.  Called
+   during dynamic linker startup or from __libc_setup_tls.  */
+void __dl_inittcb (void) attribute_hidden;
+
 /* Allocate memory for static TLS block (unless MEM is nonzero) and dtv.  */
 extern void *_dl_allocate_tls (void *mem);
 rtld_hidden_proto (_dl_allocate_tls)
diff --git a/sysdeps/nptl/dl-inittcb.c b/sysdeps/nptl/dl-inittcb.c
new file mode 100644
index 0000000000..c25424dfa6
--- /dev/null
+++ b/sysdeps/nptl/dl-inittcb.c
@@ -0,0 +1,27 @@
+/* Initialize TCB contents.  NPTL version.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <ldsodefs.h>
+#include <tls.h>
+
+void
+__dl_inittcb (void)
+{
+  /* The main thread has number 1.  */
+  THREAD_SELF->number = 1;
+}
diff --git a/sysdeps/nptl/pthread.h b/sysdeps/nptl/pthread.h
index 2b2b386ab3..e0714ed951 100644
--- a/sysdeps/nptl/pthread.h
+++ b/sysdeps/nptl/pthread.h
@@ -1148,6 +1148,10 @@ extern int pthread_atfork (void (*__prepare) (void),
 			   void (*__child) (void)) __THROW;
 
 
+/* Return a number uniquely identifying THREAD, even after its
+   termination.  */
+__uint64_t pthread_thread_number_np (pthread_t __thread_id) __THROW;
+
 #ifdef __USE_EXTERN_INLINES
 /* Optimizations.  */
 __extern_inline int
diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
index ec0ead15dd..e206f77540 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.17 GLIBC_2.17 A
 GLIBC_2.17 _Exit F
 GLIBC_2.17 _IO_2_1_stderr_ D 0xe0
diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
index 5355769974..92429a8d78 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/arm/libc.abilist b/sysdeps/unix/sysv/linux/arm/libc.abilist
index 9bafe71b51..bcd54ecdf5 100644
--- a/sysdeps/unix/sysv/linux/arm/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
index 90aa8d034f..84445a123e 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
index 4d44c30c64..caa8dff010 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
index 112fc57634..02301da334 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
index 2e8b6a4586..a3fbcb831f 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
index 3c33400f67..203a63aa27 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/microblaze/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/libc.abilist
index e1b1a579d2..a3be97ef65 100644
--- a/sysdeps/unix/sysv/linux/microblaze/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.18 GLIBC_2.18 A
 GLIBC_2.18 _Exit F
 GLIBC_2.18 _IO_2_1_stderr_ D 0x98
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
index c1550323f3..94de2ef489 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
index 3b3a172e4f..878bee4bb5 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
index 101ca7a241..94706fccb4 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
index 2d129f7170..adc3de5c88 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
index 8bc350aff8..f6198b3dbb 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.21 GLIBC_2.21 A
 GLIBC_2.21 _Exit F
 GLIBC_2.21 _IO_2_1_stderr_ D 0x98
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
index 127c426e1c..363a3a2e10 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
index a9411318e2..dfa0463282 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist
index d7bf5db601..37a34eb833 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.17 GLIBC_2.17 A
 GLIBC_2.17 _Exit F
 GLIBC_2.17 _IO_2_1_stderr_ D 0xe0
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist
index a3415a72ac..a0dbaf366a 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
index 414338f9a2..a30b304817 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 GLIBC_2.0 A
 GLIBC_2.0 _IO_adjust_column F
 GLIBC_2.0 _IO_default_doallocate F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
index f0f7a69b64..a759aa9cf5 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/sh/libc.abilist b/sysdeps/unix/sysv/linux/sh/libc.abilist
index 9f95aba898..133e0a55ef 100644
--- a/sysdeps/unix/sysv/linux/sh/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
index 83fbdf2d7e..e525ed69d6 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.0 .div F
 GLIBC_2.0 .mul F
 GLIBC_2.0 .rem F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
index ee84ad10bc..d4fb34eceb 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -3,6 +3,8 @@ GCC_3.0 _Unwind_Find_FDE F
 GCC_3.0 __deregister_frame_info_bases F
 GCC_3.0 __register_frame_info_bases F
 GCC_3.0 __register_frame_info_table_bases F
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist
index dcbfbc05ac..f598149374 100644
--- a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.12 GLIBC_2.12 A
 GLIBC_2.12 _Exit F
 GLIBC_2.12 _IO_2_1_stderr_ D 0xa0
diff --git a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist
index 53dc99c45a..cb0054f532 100644
--- a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.12 GLIBC_2.12 A
 GLIBC_2.12 _Exit F
 GLIBC_2.12 _IO_2_1_stderr_ D 0xe0
diff --git a/sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist b/sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist
index dcbfbc05ac..f598149374 100644
--- a/sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.12 GLIBC_2.12 A
 GLIBC_2.12 _Exit F
 GLIBC_2.12 _IO_2_1_stderr_ D 0xa0
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index ae4dcaa47e..70a15fa003 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.10 GLIBC_2.10 A
 GLIBC_2.10 __cxa_at_quick_exit F
 GLIBC_2.10 __posix_getopt F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
index 0dbda14796..afbdec65d5 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -1,3 +1,5 @@
+GLBIC_2.27 GLBIC_2.27 A
+GLBIC_2.27 pthread_thread_number_np F
 GLIBC_2.16 GLIBC_2.16 A
 GLIBC_2.16 _Exit F
 GLIBC_2.16 _IO_2_1_stderr_ D 0xa0
