[hurd,commited] hurd: fix gai_misc build

diff --git a/ChangeLog b/ChangeLog
index 5ef9814516..ffa7532ff7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,7 @@ 
 	(thread_attr_compare): Move function to...
 	[!defined DELAYTIMER_MAX] (DELAYTIMER_MAX): Define to INT_MAX.
 	* sysdeps/nptl/timer_routines.h: ... new header.
+	* sysdeps/mach/hurd/gai_misc.h: New file.
 
 2018-02-26  Joseph Myers  <joseph@codesourcery.com>
 
diff --git a/sysdeps/mach/hurd/gai_misc.h b/sysdeps/mach/hurd/gai_misc.h
new file mode 100644
index 0000000000..7804139baa
--- /dev/null
+++ b/sysdeps/mach/hurd/gai_misc.h
@@ -0,0 +1,67 @@ 
+/* Copyright (C) 2006-2018 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 <assert.h>
+#include <signal.h>
+#include <pthread.h>
+
+#define gai_start_notify_thread __gai_start_notify_thread
+#define gai_create_helper_thread __gai_create_helper_thread
+
+extern inline void
+__gai_start_notify_thread (void)
+{
+  sigset_t ss;
+  sigemptyset (&ss);
+  int sigerr __attribute__ ((unused));
+  sigerr = pthread_sigmask (SIG_SETMASK, &ss, NULL);
+  assert_perror (sigerr);
+}
+
+extern inline int
+__gai_create_helper_thread (pthread_t *threadp, void *(*tf) (void *),
+			    void *arg)
+{
+  pthread_attr_t attr;
+
+  /* Make sure the thread is created detached.  */
+  pthread_attr_init (&attr);
+  pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
+
+  /* The helper thread needs only very little resources.  */
+  (void) pthread_attr_setstacksize (&attr, 0x10000);
+
+  /* Block all signals in the helper thread.  To do this thoroughly we
+     temporarily have to block all signals here.  */
+  sigset_t ss;
+  sigset_t oss;
+  sigfillset (&ss);
+  int sigerr __attribute__ ((unused));
+  sigerr = pthread_sigmask (SIG_SETMASK, &ss, &oss);
+  assert_perror (sigerr);
+
+  int ret = pthread_create (threadp, &attr, tf, arg);
+
+  /* Restore the signal mask.  */
+  sigerr = pthread_sigmask (SIG_SETMASK, &oss, NULL);
+  assert_perror (sigerr);
+
+  (void) pthread_attr_destroy (&attr);
+  return ret;
+}
+
+#include_next <gai_misc.h>