Merge branch 'release/2.19/master' into ibm/2.19/masteribm/2.19/master

Conflicts:
	NEWS

40 files changed, 1955 insertions, 478 deletions

diff --git a/ChangeLog b/ChangeLog
index 48cb5d68f6..899d13ae3f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,202 @@
+2016-07-11  Florian Weimer  <fweimer@redhat.com>
+
+	[BZ #19018]
+	* stdlib/cxa_thread_atexit_impl.c (__cxa_thread_atexit_impl):
+	Mangle function pointer before storing it.
+	(__call_tls_dtors): Demangle function pointer before calling it.
+
+2016-07-11  Florian Weimer  <fweimer@redhat.com>
+
+	[BZ #18928]
+	* sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Remove
+	_dl_pointer_guard member.
+	* elf/rtld.c (_rtld_global_ro): Remove _dl_pointer_guard
+	initializer.
+	(security_init): Always set up pointer guard.
+	(process_envvars): Do not process LD_POINTER_GUARD.
+
+2016-07-11  Leonhard Holz  <leonhard.holz@web.de>
+
+	[BZ #16009]
+	* string/strxfrm_l.c (STRXFRM): Allocate fixed size cache for
+	weights and rules. Use do_xfrm_cached if data fits in cache,
+	do_xfrm otherwise.  Moved former main loop to...
+	* (do_xfrm_cached): New function.
+	* (do_xfrm): Non-caching version of do_xfrm_cached. Uses
+	find_idx, find_position and stack_push.
+	* (find_idx): New function.
+	* (find_position): Likewise.
+	* localedata/sort-test.sh: Added test run for do_xfrm.
+	* localedata/xfrm-test.c (main): Added command line option
+	-nocache to run the test with strings that are too large for
+	the STRXFRM cache.
+
+2016-05-23  Florian Weimer  <fweimer@redhat.com>
+
+	CVE-2016-4429
+	[BZ #20112]
+	* sunrpc/clnt_udp.c (clntudp_call): Use malloc/free for the error
+	payload.
+
+2016-03-25  Florian Weimer  <fweimer@redhat.com>
+
+	[BZ #19791]
+	* resolv/res_send.c (close_and_return_error): New function.
+	(send_dg): Initialize *resplen2 after reopen failure.  Call
+	close_and_return_error for error returns.  On error paths without
+	__res_iclose, initialze *resplen2 explicitly.  Update comment for
+	successful return.
+
+2016-02-15  Carlos O'Donell  <carlos@redhat.com>
+
+	[BZ #18665]
+	* resolv/nss_dns/dns-host.c (gaih_getanswer_slice): Always set
+	*herrno_p.
+	(gaih_getanswer): Document functional behviour. Return tryagain
+	if any result is tryagain.
+	* resolv/res_query.c (__libc_res_nsearch): Set buffer size to zero
+	when freed.
+	* resolv/res_send.c: Add copyright text.
+	(__libc_res_nsend): Document that MAXPACKET is expected.
+	(send_vc): Document. Remove buffer reuse.
+	(send_dg): Document. Remove buffer reuse. Set *thisanssizp to set the
+	size of the buffer. Add Dprint for truncated UDP buffer.
+
+2016-04-29  Florian Weimer  <fweimer@redhat.com>
+
+	[BZ #20010]
+	CVE-2016-3706
+	* sysdeps/posix/getaddrinfo.c
+	(convert_hostent_to_gaih_addrtuple): New function.
+	(gethosts): Call convert_hostent_to_gaih_addrtuple.
+	(gaih_inet): Use convert_hostent_to_gaih_addrtuple to convert
+	AF_INET data.
+
+2016-05-04  Florian Weimer  <fweimer@redhat.com>
+
+	[BZ #19779]
+	CVE-2016-1234
+	Avoid copying names of directory entries.
+	* posix/glob.c (DIRENT_MUST_BE, DIRENT_MIGHT_BE_SYMLINK)
+	(DIRENT_MIGHT_BE_DIR, CONVERT_D_INO, CONVERT_D_TYPE)
+	(CONVERT_DIRENT_DIRENT64, REAL_DIR_ENTRY): Remove macros.
+	(struct readdir_result): New type.
+	(D_TYPE_TO_RESULT, D_INO_TO_RESULT, READDIR_RESULT_INITIALIZER)
+	(GL_READDIR): New macros.
+	(readdir_result_might_be_symlink, readdir_result_might_be_dir)
+	(convert_dirent, convert_dirent64): New functions.
+	(glob_in_dir): Use struct readdir_result.  Call convert_dirent or
+	convert_dirent64.  Adjust references to the readdir result.
+	* sysdeps/unix/sysv/linux/i386/glob64.c:
+	(convert_dirent, GL_READDIR): Redefine for second file inclusion.
+	* posix/bug-glob2.c (LONG_NAME): Define.
+	(filesystem): Add LONG_NAME.
+	(my_DIR): Increase the size of room_for_dirent.
+
+2016-04-29  Florian Weimer  <fweimer@redhat.com>
+
+	glob: Simplify and document the interface for the GLOB_ALTDIRFUNC
+	callback function gl_readdir.
+	* posix/glob.c (NAMELEN, CONVERT_D_NAMLEN): Remove.
+	(CONVERT_DIRENT_DIRENT64): Use strcpy instead of memcpy.
+	(glob_in_dir): Remove len.  Use strdup instead of malloc and
+	memcpy to copy the name.
+	* manual/pattern.texi (Calling Glob): Document requirements for
+	implementations of the gl_readdir callback function.
+	* manual/examples/mkdirent.c: New example.
+	* posix/bug-glob2.c (my_readdir): Set d_ino to 1 unconditionally,
+	per the manual guidance.
+	* posix/tst-gnuglob.c (my_readdir): Likewise.
+
+2016-04-28  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
+	[BZ #18508]
+	* stdlib/Makefile ($(objpfx)tst-makecontext3):
+	Depend on $(libdl).
+	* stdlib/tst-makecontext.c (cf): Test if _Unwind_Backtrace
+	is not called infinitely times.
+	(backtrace_helper): New function.
+	(trace_arg): New struct.
+	(st1): Enlarge stack size.
+	* sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S:
+	(__makecontext_ret): Omit cfi_startproc and cfi_endproc.
+	* sysdeps/unix/sysv/linux/s390/s390-64/__makecontext_ret.S:
+	Likewise.
+
+2016-04-28  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
+	[BZ #18080]
+	* sysdeps/unix/sysv/linux/s390/s390-32/setcontext.S
+	(__setcontext): Use SIG_SETMASK instead of SIG_BLOCK.
+	* sysdeps/unix/sysv/linux/s390/s390-64/setcontext.S
+	(__setcontext): Likewise.
+	* sysdeps/unix/sysv/linux/s390/s390-32/swapcontext.S
+	(__swapcontext): Use SIG_SETMASK instead of SIG_BLOCK.
+	Call rt_sigprocmask syscall one time to set new signal mask
+	and retrieve the current signal mask instead of two calls.
+	* sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S
+	(__swapcontext): Likewise.
+	* stdlib/Makefile (tests): Add new testcase tst-setcontext2.
+	* stdlib/tst-setcontext2.c: New file.
+
+2016-04-01  Florian Weimer  <fweimer@redhat.com>
+
+	[BZ #19879]
+	CVE-2016-3075
+	* resolv/nss_dns/dns-network.c (_nss_dns_getnetbyname_r): Do not
+	copy name.
+
+2016-02-12  Florian Weimer  <fweimer@redhat.com>
+
+	* misc/bug18240.c (do_test): Set RLIMIT_AS.
+
+2016-01-27  Paul Eggert  <eggert@cs.ucla.edu>
+
+	[BZ #18240]
+	* misc/hsearch_r.c (isprime, __hcreate_r): Protect against
+	unsigned int wraparound.
+
+2016-01-27  Florian Weimer  <fweimer@redhat.com>
+
+	[BZ #18240]
+	* misc/bug18240.c: New test.
+	* misc/Makefile (tests): Add it.
+
+2015-08-25  Ondřej Bílka  <neleai@seznam.cz>
+
+	[BZ #18240]
+	* misc/hsearch_r.c (__hcreate_r): Handle overflow.
+
+2015-09-26  Paul Pluzhnikov  <ppluzhnikov@google.com>
+
+	[BZ #18985]
+	* time/strftime_l.c (a_wkday, f_wkday, a_month, f_month): Range check.
+	(__strftime_internal): Likewise.
+	* time/tst-strftime.c (do_bz18985): New test.
+	(do_test): Call it.
+
+2015-08-08  Paul Pluzhnikov  <ppluzhnikov@google.com>
+
+	[BZ #17905]
+	* catgets/Makefile (tst-catgets-mem): New test.
+	* catgets/catgets.c (catopen): Don't use unbounded alloca.
+	* catgets/open_catalog.c (__open_catalog): Likewise.
+	* catgets/tst-catgets.c (do_bz17905): Test unbounded alloca.
+
+2015-12-20  Siddhesh Poyarekar  <siddhesh@redhat.com>
+
+	[BZ #16758]
+	* nscd/netgroupcache.c (addinnetgrX): Succeed if triplet has
+	blank values.
+
+	[BZ #16759]
+	* inet/getnetgrent_r.c (get_nonempty_val): New function.
+	(nscd_getnetgrent): Use it.
+
+	[BZ #16760]
+	* nscd/netgroupcache.c (addgetnetgrentX): Use memmove instead
+	of stpcpy.
+
 2015-11-24  Andreas Schwab  <schwab@suse.de>
 
 	[BZ #17062]
diff --git a/NEWS b/NEWS
index 1fde5ffe18..8aa9a0dde2 100644
--- a/NEWS
+++ b/NEWS
@@ -9,11 +9,12 @@ Version 2.19.1
 
 * The following bugs are resolved with this release:
 
-  15946, 16545, 16574, 16617, 16618, 16619, 16623, 16657, 16683, 16689,
-  16695, 16701, 16706, 16707, 16739, 16740, 16743, 16815, 16878, 16882,
-  16885, 16916, 16932, 16943, 16958, 17031, 17048, 17062, 17069, 17079,
-  17137, 17153, 17187, 17213, 17263, 17269, 17325, 17555, 17625, 17630,
-  18007, 18032, 18104, 18287.
+  15946, 16009, 16545, 16574, 16617, 16618, 16619, 16623, 16657, 16683,
+  16695, 16701, 16706, 16707, 16739, 16740, 16743, 16758, 16759, 16760,
+  16815, 16878, 16882, 16885, 16916, 16932, 16943, 16958, 17031, 17048,
+  17062, 17069, 17079, 17137, 17153, 17187, 17213, 17263, 17269, 17325,
+  17555, 17625, 17630, 17905, 18007, 18032, 18080, 18104, 18240, 18287,
+  18508, 18665, 18905, 18928, 19018, 19779, 19791, 19879, 20010, 20112.
 
 * A buffer overflow in gethostbyname_r and related functions performing DNS
   requests has been fixed.  If the NSS functions were called with a
@@ -81,6 +82,38 @@ Version 2.19.1
   the get*ent functions if any of the query functions for the same database
   are used during the iteration, causing a denial-of-service condition in
   some applications.
+
+* The getnetbyname implementation in nss_dns had a potentially unbounded
+  alloca call (in the form of a call to strdupa), leading to a stack
+  overflow (stack exhaustion) and a crash if getnetbyname is invoked
+  on a very long name.  (CVE-2016-3075)
+
+* The glob function suffered from a stack-based buffer overflow when it was
+  called with the GLOB_ALTDIRFUNC flag and encountered a long file name.
+  Reported by Alexander Cherepanov.  (CVE-2016-1234)
+
+* Previously, getaddrinfo copied large amounts of address data to the stack,
+  even after the fix for CVE-2013-4458 has been applied, potentially
+  resulting in a stack overflow.  getaddrinfo now uses a heap allocation
+  instead.  Reported by Michael Petlan.  (CVE-2016-3706)
+
+* A stack-based buffer overflow was found in libresolv when invoked from
+  libnss_dns, allowing specially crafted DNS responses to seize control
+  of execution flow in the DNS client.  The buffer overflow occurs in
+  the functions send_dg (send datagram) and send_vc (send TCP) for the
+  NSS module libnss_dns.so.2 when calling getaddrinfo with AF_UNSPEC
+  family.  The use of AF_UNSPEC triggers the low-level resolver code to
+  send out two parallel queries for A and AAAA.  A mismanagement of the
+  buffers used for those queries could result in the response of a query
+  writing beyond the alloca allocated buffer created by
+  _nss_dns_gethostbyname4_r.  Buffer management is simplified to remove
+  the overflow.  Thanks to the Google Security Team and Red Hat for
+  reporting the security impact of this issue, and Robert Holiday of
+  Ciena for reporting the related bug 18665. (CVE-2015-7547)
+
+* The Sun RPC UDP client could exhaust all available stack space when
+  flooded with crafted ICMP and UDP messages.  Reported by Aldy Hernandez'
+  alloca plugin for GCC.  (CVE-2016-4429)
 
 Version 2.19
 
diff --git a/catgets/Makefile b/catgets/Makefile
index c95442d369..8c39e3d95f 100644
--- a/catgets/Makefile
+++ b/catgets/Makefile
@@ -45,14 +45,14 @@ catgets-CPPFLAGS := -DNLSPATH='"$(msgcatdir)/%L/%N:$(msgcatdir)/%L/LC_MESSAGES/%
 CPPFLAGS-gencat = -DNOT_IN_libc
 
 generated = de.msg test1.cat test1.h test2.cat test2.h sample.SJIS.cat \
-	    test-gencat.h
+	    test-gencat.h tst-catgets.mtrace tst-catgets-mem.out
 generated-dirs = de
 
-tst-catgets-ENV = NLSPATH="$(objpfx)%l/%N.cat" LANG=de
+tst-catgets-ENV = NLSPATH="$(objpfx)%l/%N.cat" LANG=de MALLOC_TRACE=$(objpfx)tst-catgets.mtrace
 
 ifeq ($(run-built-tests),yes)
 tests: $(objpfx)de/libc.cat $(objpfx)test1.cat $(objpfx)test2.cat \
-       $(objpfx)test-gencat.out
+       $(objpfx)test-gencat.out $(objpfx)tst-catgets-mem.out
 # This test just checks whether the program produces any error or not.
 # The result is not tested.
 $(objpfx)test1.cat: test1.msg $(objpfx)gencat
@@ -80,4 +80,9 @@ $(objpfx)test-gencat.out: test-gencat.sh $(objpfx)test-gencat \
 $(objpfx)sample.SJIS.cat: sample.SJIS $(objpfx)gencat
 	GCONV_PATH=$(common-objpfx)iconvdata LC_ALL=C \
 	$(built-program-cmd) -H $(objpfx)test-gencat.h < $(word 1,$^) > $@
+
+$(objpfx)tst-catgets-mem.out: $(objpfx)tst-catgets.out
+	$(common-objpfx)malloc/mtrace $(objpfx)tst-catgets.mtrace > $@; \
+	$(evaluate-test)
+
 endif
diff --git a/catgets/catgets.c b/catgets/catgets.c
index eac2827214..820c0f6ed9 100644
--- a/catgets/catgets.c
+++ b/catgets/catgets.c
@@ -16,7 +16,6 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-#include <alloca.h>
 #include <errno.h>
 #include <locale.h>
 #include <nl_types.h>
@@ -35,6 +34,7 @@ catopen (const char *cat_name, int flag)
   __nl_catd result;
   const char *env_var = NULL;
   const char *nlspath = NULL;
+  char *tmp = NULL;
 
   if (strchr (cat_name, '/') == NULL)
     {
@@ -54,7 +54,10 @@ catopen (const char *cat_name, int flag)
 	{
 	  /* Append the system dependent directory.  */
 	  size_t len = strlen (nlspath) + 1 + sizeof NLSPATH;
-	  char *tmp = alloca (len);
+	  tmp = malloc (len);
+
+	  if (__glibc_unlikely (tmp == NULL))
+	    return (nl_catd) -1;
 
 	  __stpcpy (__stpcpy (__stpcpy (tmp, nlspath), ":"), NLSPATH);
 	  nlspath = tmp;
@@ -65,16 +68,18 @@ catopen (const char *cat_name, int flag)
 
   result = (__nl_catd) malloc (sizeof (*result));
   if (result == NULL)
-    /* We cannot get enough memory.  */
-    return (nl_catd) -1;
-
-  if (__open_catalog (cat_name, nlspath, env_var, result) != 0)
+    {
+      /* We cannot get enough memory.  */
+      result = (nl_catd) -1;
+    }
+  else if (__open_catalog (cat_name, nlspath, env_var, result) != 0)
     {
       /* Couldn't open the file.  */
       free ((void *) result);
-      return (nl_catd) -1;
+      result = (nl_catd) -1;
     }
 
+  free (tmp);
   return (nl_catd) result;
 }
 
diff --git a/catgets/open_catalog.c b/catgets/open_catalog.c
index bc44f98247..5fa4011446 100644
--- a/catgets/open_catalog.c
+++ b/catgets/open_catalog.c
@@ -47,6 +47,7 @@ __open_catalog (const char *cat_name, const char *nlspath, const char *env_var,
   size_t tab_size;
   const char *lastp;
   int result = -1;
+  char *buf = NULL;
 
   if (strchr (cat_name, '/') != NULL || nlspath == NULL)
     fd = open_not_cancel_2 (cat_name, O_RDONLY);
@@ -57,23 +58,23 @@ __open_catalog (const char *cat_name, const char *nlspath, const char *env_var,
   if (__builtin_expect (bufact + (n) >= bufmax, 0))			      \
     {									      \
       char *old_buf = buf;						      \
-      bufmax += 256 + (n);						      \
-      buf = (char *) alloca (bufmax);					      \
-      memcpy (buf, old_buf, bufact);					      \
+      bufmax += (bufmax < 256 + (n)) ? 256 + (n) : bufmax;		      \
+      buf = realloc (buf, bufmax);					      \
+      if (__glibc_unlikely (buf == NULL))				      \
+	{								      \
+	  free (old_buf);						      \
+	  return -1;							      \
+	}								      \
     }
 
       /* The RUN_NLSPATH variable contains a colon separated list of
 	 descriptions where we expect to find catalogs.  We have to
 	 recognize certain % substitutions and stop when we found the
 	 first existing file.  */
-      char *buf;
       size_t bufact;
-      size_t bufmax;
+      size_t bufmax = 0;
       size_t len;
 
-      buf = NULL;
-      bufmax = 0;
-
       fd = -1;
       while (*run_nlspath != '\0')
 	{
@@ -188,7 +189,10 @@ __open_catalog (const char *cat_name, const char *nlspath, const char *env_var,
 
   /* Avoid dealing with directories and block devices */
   if (__builtin_expect (fd, 0) < 0)
-    return -1;
+    {
+      free (buf);
+      return -1;
+    }
 
   if (__builtin_expect (__fxstat64 (_STAT_VER, fd, &st), 0) < 0)
     goto close_unlock_return;
@@ -325,6 +329,7 @@ __open_catalog (const char *cat_name, const char *nlspath, const char *env_var,
   /* Release the lock again.  */
  close_unlock_return:
   close_not_cancel_no_status (fd);
+  free (buf);
 
   return result;
 }
diff --git a/catgets/tst-catgets.c b/catgets/tst-catgets.c
index fdaa834949..25ef056ef2 100644
--- a/catgets/tst-catgets.c
+++ b/catgets/tst-catgets.c
@@ -1,7 +1,10 @@
+#include <assert.h>
 #include <mcheck.h>
 #include <nl_types.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
+#include <sys/resource.h>
 
 
 static const char *msgs[] =
@@ -12,6 +15,33 @@ static const char *msgs[] =
 };
 #define nmsgs (sizeof (msgs) / sizeof (msgs[0]))
 
+
+/* Test for unbounded alloca.  */
+static int
+do_bz17905 (void)
+{
+  char *buf;
+  struct rlimit rl;
+  nl_catd result;
+
+  const int sz = 1024 * 1024;
+
+  getrlimit (RLIMIT_STACK, &rl);
+  rl.rlim_cur = sz;
+  setrlimit (RLIMIT_STACK, &rl);
+
+  buf = malloc (sz + 1);
+  memset (buf, 'A', sz);
+  buf[sz] = '\0';
+  setenv ("NLSPATH", buf, 1);
+
+  result = catopen (buf, NL_CAT_LOCALE);
+  assert (result == (nl_catd) -1);
+
+  free (buf);
+  return 0;
+}
+
 #define ROUNDS 5
 
 int
@@ -62,5 +92,6 @@ main (void)
 	}
     }
 
+  result += do_bz17905 ();
   return result;
 }
diff --git a/elf/rtld.c b/elf/rtld.c
index 6dcbabc284..375c47d72c 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -162,7 +162,6 @@ struct rtld_global_ro _rtld_global_ro attribute_relro =
     ._dl_hwcap_mask = HWCAP_IMPORTANT,
     ._dl_lazy = 1,
     ._dl_fpu_control = _FPU_DEFAULT,
-    ._dl_pointer_guard = 1,
     ._dl_pagesize = EXEC_PAGESIZE,
     ._dl_inhibit_cache = 0,
 
@@ -857,15 +856,12 @@ security_init (void)
 #endif
 
   /* Set up the pointer guard as well, if necessary.  */
-  if (GLRO(dl_pointer_guard))
-    {
-      uintptr_t pointer_chk_guard = _dl_setup_pointer_guard (_dl_random,
-							     stack_chk_guard);
+  uintptr_t pointer_chk_guard
+    = _dl_setup_pointer_guard (_dl_random, stack_chk_guard);
 #ifdef THREAD_SET_POINTER_GUARD
-      THREAD_SET_POINTER_GUARD (pointer_chk_guard);
+  THREAD_SET_POINTER_GUARD (pointer_chk_guard);
 #endif
-      __pointer_chk_guard_local = pointer_chk_guard;
-    }
+  __pointer_chk_guard_local = pointer_chk_guard;
 
   /* We do not need the _dl_random value anymore.  The less
      information we leave behind, the better, so clear the
@@ -2605,9 +2601,6 @@ process_envvars (enum mode *modep)
 	      GLRO(dl_use_load_bias) = envline[14] == '1' ? -1 : 0;
 	      break;
 	    }
-
-	  if (memcmp (envline, "POINTER_GUARD", 13) == 0)
-	    GLRO(dl_pointer_guard) = envline[14] != '0';
 	  break;
 
 	case 14:
diff --git a/inet/getnetgrent_r.c b/inet/getnetgrent_r.c
index 62cdfda9cb..f6d064dbb5 100644
--- a/inet/getnetgrent_r.c
+++ b/inet/getnetgrent_r.c
@@ -235,6 +235,14 @@ endnetgrent (void)
 }
 
 #ifdef USE_NSCD
+static const char *
+get_nonempty_val (const char *in)
+{
+  if (*in == '\0')
+    return NULL;
+  return in;
+}
+
 static enum nss_status
 nscd_getnetgrent (struct __netgrent *datap, char *buffer, size_t buflen,
 		  int *errnop)
@@ -243,11 +251,11 @@ nscd_getnetgrent (struct __netgrent *datap, char *buffer, size_t buflen,
     return NSS_STATUS_UNAVAIL;
 
   datap->type = triple_val;
-  datap->val.triple.host = datap->cursor;
+  datap->val.triple.host = get_nonempty_val (datap->cursor);
   datap->cursor = (char *) __rawmemchr (datap->cursor, '\0') + 1;
-  datap->val.triple.user = datap->cursor;
+  datap->val.triple.user = get_nonempty_val (datap->cursor);
   datap->cursor = (char *) __rawmemchr (datap->cursor, '\0') + 1;
-  datap->val.triple.domain = datap->cursor;
+  datap->val.triple.domain = get_nonempty_val (datap->cursor);
   datap->cursor = (char *) __rawmemchr (datap->cursor, '\0') + 1;
 
   return NSS_STATUS_SUCCESS;
diff --git a/localedata/sort-test.sh b/localedata/sort-test.sh
index 8a7ca89688..b01a78ea14 100644
--- a/localedata/sort-test.sh
+++ b/localedata/sort-test.sh
@@ -49,11 +49,17 @@ for l in $lang; do
    ${common_objpfx}localedata/xfrm-test $id < $cns.in \
    > ${common_objpfx}localedata/$cns.xout || here=1
   cmp -s $cns.in ${common_objpfx}localedata/$cns.xout || here=1
+  LOCPATH=${common_objpfx}localedata GCONV_PATH=${common_objpfx}/iconvdata \
+   LC_ALL=$l ${test_program_prefix} \
+   ${common_objpfx}localedata/xfrm-test $id -nocache < $cns.in \
+   > ${common_objpfx}localedata/$cns.nocache.xout || here=1
+  cmp -s $cns.in ${common_objpfx}localedata/$cns.nocache.xout || here=1
   if test $here -eq 0; then
     echo "$l xfrm-test OK"
   else
     echo "$l xfrm-test FAIL"
     diff -u $cns.in ${common_objpfx}localedata/$cns.xout | sed 's/^/  /'
+    diff -u $cns.in ${common_objpfx}localedata/$cns.nocache.xout | sed 's/^/  /'
     status=1
   fi
 done
diff --git a/localedata/xfrm-test.c b/localedata/xfrm-test.c
index d2aba7d26e..5cf29f60c9 100644
--- a/localedata/xfrm-test.c
+++ b/localedata/xfrm-test.c
@@ -23,7 +23,10 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <stdbool.h>
 
+/* Keep in sync with string/strxfrm_l.c.  */
+#define SMALL_STR_SIZE 4095
 
 struct lines
 {
@@ -37,6 +40,7 @@ int
 main (int argc, char *argv[])
 {
   int result = 0;
+  bool nocache = false;
   size_t nstrings, nstrings_max;
   struct lines *strings;
   char *line = NULL;
@@ -44,7 +48,18 @@ main (int argc, char *argv[])
   size_t n;
 
   if (argc < 2)
-    error (1, 0, "usage: %s <random seed>", argv[0]);
+    error (1, 0, "usage: %s <random seed> [-nocache]", argv[0]);
+
+  if (argc == 3)
+    {
+      if (strcmp (argv[2], "-nocache") == 0)
+	nocache = true;
+      else
+	{
+	  printf ("Unknown option %s!\n", argv[2]);
+	  exit (1);
+	}
+    }
 
   setlocale (LC_ALL, "");
 
@@ -59,9 +74,9 @@ main (int argc, char *argv[])
 
   while (1)
     {
-      char saved, *newp;
-      int needed;
-      int l;
+      char saved, *word, *newp;
+      size_t l, line_len, needed;
+
       if (getline (&line, &len, stdin) < 0)
 	break;
 
@@ -83,10 +98,35 @@ main (int argc, char *argv[])
 
       saved = line[l];
       line[l] = '\0';
-      needed = strxfrm (NULL, line, 0);
+
+      if (nocache)
+	{
+	  line_len = strlen (line);
+	  word = malloc (line_len + SMALL_STR_SIZE + 1);
+	  if (word == NULL)
+	    {
+	      printf ("malloc failed: %m\n");
+	      exit (1);
+	    }
+	  memset (word, ' ', SMALL_STR_SIZE);
+	  memcpy (word + SMALL_STR_SIZE, line, line_len);
+	  word[line_len + SMALL_STR_SIZE] = '\0';
+	}
+      else
+        word = line;
+
+      needed = strxfrm (NULL, word, 0);
       newp = malloc (needed + 1);
-      strxfrm (newp, line, needed + 1);
+      if (newp == NULL)
+	{
+	  printf ("malloc failed: %m\n");
+	  exit (1);
+	}
+      strxfrm (newp, word, needed + 1);
       strings[nstrings].xfrm = newp;
+
+      if (nocache)
+	free (word);
       line[l] = saved;
       ++nstrings;
     }
diff --git a/manual/examples/mkdirent.c b/manual/examples/mkdirent.c
new file mode 100644
index 0000000000..f8400f46d7
--- /dev/null
+++ b/manual/examples/mkdirent.c
@@ -0,0 +1,42 @@
+/* Example for creating a struct dirent object for use with glob.
+   Copyright (C) 2016 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 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, if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <dirent.h>
+#include <errno.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct dirent *
+mkdirent (const char *name)
+{
+  size_t dirent_size = offsetof (struct dirent, d_name) + 1;
+  size_t name_length = strlen (name);
+  size_t total_size = dirent_size + name_length;
+  if (total_size < dirent_size)
+    {
+      errno = ENOMEM;
+      return NULL;
+    }
+  struct dirent *result = malloc (total_size);
+  if (result == NULL)
+    return NULL;
+  result->d_type = DT_UNKNOWN;
+  result->d_ino = 1;            /* Do not skip this entry.  */
+  memcpy (result->d_name, name, name_length + 1);
+  return result;
+}
diff --git a/manual/pattern.texi b/manual/pattern.texi
index da848c340b..4cf26a7cf3 100644
--- a/manual/pattern.texi
+++ b/manual/pattern.texi
@@ -237,7 +237,44 @@ function used to read the contents of a directory.  It is used if the
 @code{GLOB_ALTDIRFUNC} bit is set in the flag parameter.  The type of
 this field is @w{@code{struct dirent *(*) (void *)}}.
 
-This is a GNU extension.
+An implementation of @code{gl_readdir} needs to initialize the following
+members of the @code{struct dirent} object:
+
+@table @code
+@item d_type
+This member should be set to the file type of the entry if it is known.
+Otherwise, the value @code{DT_UNKNOWN} can be used.  The @code{glob}
+function may use the specified file type to avoid callbacks in cases
+where the file type indicates that the data is not required.
+
+@item d_ino
+This member needs to be non-zero, otherwise @code{glob} may skip the
+current entry and call the @code{gl_readdir} callback function again to
+retrieve another entry.
+
+@item d_name
+This member must be set to the name of the entry.  It must be
+null-terminated.
+@end table
+
+The example below shows how to allocate a @code{struct dirent} object
+containing a given name.
+
+@smallexample
+@include mkdirent.c.texi
+@end smallexample
+
+The @code{glob} function reads the @code{struct dirent} members listed
+above and makes a copy of the file name in the @code{d_name} member
+immediately after the @code{gl_readdir} callback function returns.
+Future invocations of any of the callback functions may dealloacte or
+reuse the buffer.  It is the responsibility of the caller of the
+@code{glob} function to allocate and deallocate the buffer, around the
+call to @code{glob} or using the callback functions.  For example, an
+application could allocate the buffer in the @code{gl_readdir} callback
+function, and deallocate it in the @code{gl_closedir} callback function.
+
+The @code{gl_readdir} member is a GNU extension.
 
 @item gl_opendir
 The address of an alternative implementation of the @code{opendir}
diff --git a/misc/Makefile b/misc/Makefile
index b039182fa0..ad9e92137a 100644
--- a/misc/Makefile
+++ b/misc/Makefile
@@ -76,7 +76,8 @@ install-lib := libg.a
 gpl2lgpl := error.c error.h
 
 tests := tst-dirname tst-tsearch tst-fdset tst-efgcvt tst-mntent tst-hsearch \
-	 tst-error1 tst-pselect tst-insremque tst-mntent2 bug-hsearch1
+	 tst-error1 tst-pselect tst-insremque tst-mntent2 bug-hsearch1 \
+	 bug18240
 ifeq ($(run-built-tests),yes)
 tests: $(objpfx)tst-error1-mem
 endif
diff --git a/misc/bug18240.c b/misc/bug18240.c
new file mode 100644
index 0000000000..773586ee10
--- /dev/null
+++ b/misc/bug18240.c
@@ -0,0 +1,97 @@
+/* Test integer wraparound in hcreate.
+   Copyright (C) 2016 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 <errno.h>
+#include <limits.h>
+#include <search.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/resource.h>
+
+static void
+test_size (size_t size)
+{
+  int res = hcreate (size);
+  if (res == 0)
+    {
+      if (errno == ENOMEM)
+        return;
+      printf ("error: hcreate (%zu): %m\n", size);
+      exit (1);
+    }
+  char *keys[100];
+  for (int i = 0; i < 100; ++i)
+    {
+      if (asprintf (keys + i, "%d", i) < 0)
+        {
+          printf ("error: asprintf: %m\n");
+          exit (1);
+        }
+      ENTRY e = { keys[i], (char *) "value" };
+      if (hsearch (e, ENTER) == NULL)
+        {
+          printf ("error: hsearch (\"%s\"): %m\n", keys[i]);
+          exit (1);
+        }
+    }
+  hdestroy ();
+
+  for (int i = 0; i < 100; ++i)
+    free (keys[i]);
+}
+
+static int
+do_test (void)
+{
+  /* Limit the size of the process, so that memory allocation will
+     fail without impacting the entire system.  */
+  {
+    struct rlimit limit;
+    if (getrlimit (RLIMIT_AS, &limit) != 0)
+      {
+        printf ("getrlimit (RLIMIT_AS) failed: %m\n");
+        return 1;
+      }
+    long target = 100 * 1024 * 1024;
+    if (limit.rlim_cur == RLIM_INFINITY || limit.rlim_cur > target)
+      {
+        limit.rlim_cur = target;
+        if (setrlimit (RLIMIT_AS, &limit) != 0)
+          {
+            printf ("setrlimit (RLIMIT_AS) failed: %m\n");
+            return 1;
+          }
+      }
+  }
+
+  test_size (500);
+  test_size (-1);
+  test_size (-3);
+  test_size (INT_MAX - 2);
+  test_size (INT_MAX - 1);
+  test_size (INT_MAX);
+  test_size (((unsigned) INT_MAX) + 1);
+  test_size (UINT_MAX - 2);
+  test_size (UINT_MAX - 1);
+  test_size (UINT_MAX);
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/misc/hsearch_r.c b/misc/hsearch_r.c
index 81c27d800c..af5521234c 100644
--- a/misc/hsearch_r.c
+++ b/misc/hsearch_r.c
@@ -19,7 +19,7 @@
 #include <errno.h>
 #include <malloc.h>
 #include <string.h>
-
+#include <stdint.h>
 #include <search.h>
 
 /* [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986
@@ -46,15 +46,12 @@ static int
 isprime (unsigned int number)
 {
   /* no even number will be passed */
-  unsigned int div = 3;
-
-  while (div * div < number && number % div != 0)
-    div += 2;
-
-  return number % div != 0;
+  for (unsigned int div = 3; div <= number / div; div += 2)
+    if (number % div == 0)
+      return 0;
+  return 1;
 }
 
-
 /* Before using the hash table we must allocate memory for it.
    Test for an existing table are done. We allocate one element
    more as the found prime number says. This is done for more effective
@@ -81,10 +78,19 @@ hcreate_r (nel, htab)
      use will not work.  */
   if (nel < 3)
     nel = 3;
-  /* Change nel to the first prime number not smaller as nel. */
-  nel |= 1;      /* make odd */
-  while (!isprime (nel))
-    nel += 2;
+
+  /* Change nel to the first prime number in the range [nel, UINT_MAX - 2],
+     The '- 2' means 'nel += 2' cannot overflow.  */
+  for (nel |= 1; ; nel += 2)
+    {
+      if (UINT_MAX - 2 < nel)
+	{
+	  __set_errno (ENOMEM);
+	  return 0;
+	}
+      if (isprime (nel))
+	break;
+    }
 
   htab->size = nel;
   htab->filled = 0;
diff --git a/nscd/netgroupcache.c b/nscd/netgroupcache.c
index 084f74df2f..c61d10b170 100644
--- a/nscd/netgroupcache.c
+++ b/nscd/netgroupcache.c
@@ -211,6 +211,10 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
 			    const char *nuser = data.val.triple.user;
 			    const char *ndomain = data.val.triple.domain;
 
+			    size_t hostlen = strlen (nhost ?: "") + 1;
+			    size_t userlen = strlen (nuser ?: "") + 1;
+			    size_t domainlen = strlen (ndomain ?: "") + 1;
+
 			    if (nhost == NULL || nuser == NULL || ndomain == NULL
 				|| nhost > nuser || nuser > ndomain)
 			      {
@@ -228,9 +232,6 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
 				     : last + strlen (last) + 1 - buffer);
 
 				/* We have to make temporary copies.  */
-				size_t hostlen = strlen (nhost ?: "") + 1;
-				size_t userlen = strlen (nuser ?: "") + 1;
-				size_t domainlen = strlen (ndomain ?: "") + 1;
 				size_t needed = hostlen + userlen + domainlen;
 
 				if (buflen - req->key_len - bufused < needed)
@@ -264,9 +265,12 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
 			      }
 
 			    char *wp = buffer + buffilled;
-			    wp = stpcpy (wp, nhost) + 1;
-			    wp = stpcpy (wp, nuser) + 1;
-			    wp = stpcpy (wp, ndomain) + 1;
+			    wp = memmove (wp, nhost ?: "", hostlen);
+			    wp += hostlen;
+			    wp = memmove (wp, nuser ?: "", userlen);
+			    wp += userlen;
+			    wp = memmove (wp, ndomain ?: "", domainlen);
+			    wp += domainlen;
 			    buffilled = wp - buffer;
 			    ++nentries;
 			  }
@@ -562,15 +566,19 @@ addinnetgrX (struct database_dyn *db, int fd, request_header *req,
 	{
 	  bool success = true;
 
-	  if (host != NULL)
+	  /* For the host, user and domain in each triplet, we assume success
+	     if the value is blank because that is how the wildcard entry to
+	     match anything is stored in the netgroup cache.  */
+	  if (host != NULL && *triplets != '\0')
 	    success = strcmp (host, triplets) == 0;
 	  triplets = (const char *) rawmemchr (triplets, '\0') + 1;
 
-	  if (success && user != NULL)
+	  if (success && user != NULL && *triplets != '\0')
 	    success = strcmp (user, triplets) == 0;
 	  triplets = (const char *) rawmemchr (triplets, '\0') + 1;
 
-	  if (success && (domain == NULL || strcmp (domain, triplets) == 0))
+	  if (success && (domain == NULL || *triplets == '\0'
+			  || strcmp (domain, triplets) == 0))
 	    {
 	      dataset->resp.result = 1;
 	      break;
diff --git a/posix/bug-glob2.c b/posix/bug-glob2.c
index 8e21deb658..3f9c620299 100644
--- a/posix/bug-glob2.c
+++ b/posix/bug-glob2.c
@@ -40,6 +40,17 @@
 # define PRINTF(fmt, args...)
 #endif
 
+#define LONG_NAME \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
+  "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
 
 static struct
 {
@@ -58,6 +69,7 @@ static struct
       { ".", 3, DT_DIR, 0755 },
       { "..", 3, DT_DIR, 0755 },
       { "a", 3, DT_REG, 0644 },
+      { LONG_NAME, 3, DT_REG, 0644 },
     { "unreadable", 2, DT_DIR, 0111 },
       { ".", 3, DT_DIR, 0111 },
       { "..", 3, DT_DIR, 0755 },
@@ -75,7 +87,7 @@ typedef struct
   int level;
   int idx;
   struct dirent d;
-  char room_for_dirent[NAME_MAX];
+  char room_for_dirent[sizeof (LONG_NAME)];
 } my_DIR;
 
 
@@ -193,7 +205,7 @@ my_readdir (void *gdir)
       return NULL;
     }
 
-  dir->d.d_ino = dir->idx;
+  dir->d.d_ino = 1;		/* glob should not skip this entry.  */
 
 #ifdef _DIRENT_HAVE_D_TYPE
   dir->d.d_type = filesystem[dir->idx].type;
diff --git a/posix/glob.c b/posix/glob.c
index f1431088a2..ae3b8b770f 100644
--- a/posix/glob.c
+++ b/posix/glob.c
@@ -24,7 +24,9 @@
 #include <errno.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <stdbool.h>
 #include <stddef.h>
+#include <stdint.h>
 
 /* Outcomment the following line for production quality code.  */
 /* #define NDEBUG 1 */
@@ -57,10 +59,8 @@
 
 #if defined HAVE_DIRENT_H || defined __GNU_LIBRARY__
 # include <dirent.h>
-# define NAMLEN(dirent) strlen((dirent)->d_name)
 #else
 # define dirent direct
-# define NAMLEN(dirent) (dirent)->d_namlen
 # ifdef HAVE_SYS_NDIR_H
 #  include <sys/ndir.h>
 # endif
@@ -75,82 +75,8 @@
 # endif /* HAVE_VMSDIR_H */
 #endif
 
-
-/* In GNU systems, <dirent.h> defines this macro for us.  */
-#ifdef _D_NAMLEN
-# undef NAMLEN
-# define NAMLEN(d) _D_NAMLEN(d)
-#endif
-
-/* When used in the GNU libc the symbol _DIRENT_HAVE_D_TYPE is available
-   if the `d_type' member for `struct dirent' is available.
-   HAVE_STRUCT_DIRENT_D_TYPE plays the same role in GNULIB.  */
-#if defined _DIRENT_HAVE_D_TYPE || defined HAVE_STRUCT_DIRENT_D_TYPE
-/* True if the directory entry D must be of type T.  */
-# define DIRENT_MUST_BE(d, t)	((d)->d_type == (t))
-
-/* True if the directory entry D might be a symbolic link.  */
-# define DIRENT_MIGHT_BE_SYMLINK(d) \
-    ((d)->d_type == DT_UNKNOWN || (d)->d_type == DT_LNK)
-
-/* True if the directory entry D might be a directory.  */
-# define DIRENT_MIGHT_BE_DIR(d)	 \
-    ((d)->d_type == DT_DIR || DIRENT_MIGHT_BE_SYMLINK (d))
-
-#else /* !HAVE_D_TYPE */
-# define DIRENT_MUST_BE(d, t)		false
-# define DIRENT_MIGHT_BE_SYMLINK(d)	true
-# define DIRENT_MIGHT_BE_DIR(d)		true
-#endif /* HAVE_D_TYPE */
-
-/* If the system has the `struct dirent64' type we use it internally.  */
-#if defined _LIBC && !defined COMPILE_GLOB64
-# if defined HAVE_DIRENT_H || defined __GNU_LIBRARY__
-#  define CONVERT_D_NAMLEN(d64, d32)
-# else
-#  define CONVERT_D_NAMLEN(d64, d32) \
-  (d64)->d_namlen = (d32)->d_namlen;
-# endif
-
-# if (defined POSIX || defined WINDOWS32) && !defined __GNU_LIBRARY__
-#  define CONVERT_D_INO(d64, d32)
-# else
-#  define CONVERT_D_INO(d64, d32) \
-  (d64)->d_ino = (d32)->d_ino;
-# endif
-
-# ifdef _DIRENT_HAVE_D_TYPE
-#  define CONVERT_D_TYPE(d64, d32) \
-  (d64)->d_type = (d32)->d_type;
-# else
-#  define CONVERT_D_TYPE(d64, d32)
-# endif
-
-# define CONVERT_DIRENT_DIRENT64(d64, d32) \
-  memcpy ((d64)->d_name, (d32)->d_name, NAMLEN (d32) + 1);		      \
-  CONVERT_D_NAMLEN (d64, d32)						      \
-  CONVERT_D_INO (d64, d32)						      \
-  CONVERT_D_TYPE (d64, d32)
-#endif
-
-
-#if (defined POSIX || defined WINDOWS32) && !defined __GNU_LIBRARY__
-/* Posix does not require that the d_ino field be present, and some
-   systems do not provide it. */
-# define REAL_DIR_ENTRY(dp) 1
-#else
-# define REAL_DIR_ENTRY(dp) (dp->d_ino != 0)
-#endif /* POSIX */
-
 #include <stdlib.h>
 #include <string.h>
-
-/* NAME_MAX is usually defined in <dirent.h> or <limits.h>.  */
-#include <limits.h>
-#ifndef NAME_MAX
-# define NAME_MAX (sizeof (((struct dirent *) 0)->d_name))
-#endif
-
 #include <alloca.h>
 
 #ifdef _LIBC
@@ -195,8 +121,111 @@
 
 static const char *next_brace_sub (const char *begin, int flags) __THROWNL;
 
+/* A representation of a directory entry which does not depend on the
+   layout of struct dirent, or the size of ino_t.  */
+struct readdir_result
+{
+  const char *name;
+# if defined _DIRENT_HAVE_D_TYPE || defined HAVE_STRUCT_DIRENT_D_TYPE
+  uint8_t type;
+# endif
+  bool skip_entry;
+};
+
+# if defined _DIRENT_HAVE_D_TYPE || defined HAVE_STRUCT_DIRENT_D_TYPE
+/* Initializer based on the d_type member of struct dirent.  */
+#  define D_TYPE_TO_RESULT(source) (source)->d_type,
+
+/* True if the directory entry D might be a symbolic link.  */
+static bool
+readdir_result_might_be_symlink (struct readdir_result d)
+{
+  return d.type == DT_UNKNOWN || d.type == DT_LNK;
+}
+
+/* True if the directory entry D might be a directory.  */
+static bool
+readdir_result_might_be_dir (struct readdir_result d)
+{
+  return d.type == DT_DIR || readdir_result_might_be_symlink (d);
+}
+# else /* defined _DIRENT_HAVE_D_TYPE || defined HAVE_STRUCT_DIRENT_D_TYPE */
+#  define D_TYPE_TO_RESULT(source)
+
+/* If we do not have type information, symbolic links and directories
+   are always a possibility.  */
+
+static bool
+readdir_result_might_be_symlink (struct readdir_result d)
+{
+  return true;
+}
+
+static bool
+readdir_result_might_be_dir (struct readdir_result d)
+{
+  return true;
+}
+
+# endif /* defined _DIRENT_HAVE_D_TYPE || defined HAVE_STRUCT_DIRENT_D_TYPE */
+
+# if (defined POSIX || defined WINDOWS32) && !defined __GNU_LIBRARY__
+/* Initializer for skip_entry.  POSIX does not require that the d_ino
+   field be present, and some systems do not provide it. */
+#  define D_INO_TO_RESULT(source) false,
+# else
+#  define D_INO_TO_RESULT(source) (source)->d_ino == 0,
+# endif
+
+/* Construct an initializer for a struct readdir_result object from a
+   struct dirent *.  No copy of the name is made.  */
+#define READDIR_RESULT_INITIALIZER(source) \
+  {					   \
+    source->d_name,			   \
+    D_TYPE_TO_RESULT (source)		   \
+    D_INO_TO_RESULT (source)		   \
+  }
+
 #endif /* !defined _LIBC || !defined GLOB_ONLY_P */
 
+/* Call gl_readdir on STREAM.  This macro can be overridden to reduce
+   type safety if an old interface version needs to be supported.  */
+#ifndef GL_READDIR
+# define GL_READDIR(pglob, stream) ((pglob)->gl_readdir (stream))
+#endif
+
+/* Extract name and type from directory entry.  No copy of the name is
+   made.  If SOURCE is NULL, result name is NULL.  Keep in sync with
+   convert_dirent64 below.  */
+static struct readdir_result
+convert_dirent (const struct dirent *source)
+{
+  if (source == NULL)
+    {
+      struct readdir_result result = { NULL, };
+      return result;
+    }
+  struct readdir_result result = READDIR_RESULT_INITIALIZER (source);
+  return result;
+}
+
+#ifndef COMPILE_GLOB64
+/* Like convert_dirent, but works on struct dirent64 instead.  Keep in
+   sync with convert_dirent above.  */
+static struct readdir_result
+convert_dirent64 (const struct dirent64 *source)
+{
+  if (source == NULL)
+    {
+      struct readdir_result result = { NULL, };
+      return result;
+    }
+  struct readdir_result result = READDIR_RESULT_INITIALIZER (source);
+  return result;
+}
+#endif
+
+
 #ifndef attribute_hidden
 # define attribute_hidden
 #endif
@@ -1561,56 +1590,36 @@ glob_in_dir (const char *pattern, const char *directory, int flags,
 
 	  while (1)
 	    {
-	      const char *name;
-	      size_t len;
-#if defined _LIBC && !defined COMPILE_GLOB64
-	      struct dirent64 *d;
-	      union
-		{
-		  struct dirent64 d64;
-		  char room [offsetof (struct dirent64, d_name[0])
-			     + NAME_MAX + 1];
-		}
-	      d64buf;
-
-	      if (__builtin_expect (flags & GLOB_ALTDIRFUNC, 0))
-		{
-		  struct dirent *d32 = (*pglob->gl_readdir) (stream);
-		  if (d32 != NULL)
-		    {
-		      CONVERT_DIRENT_DIRENT64 (&d64buf.d64, d32);
-		      d = &d64buf.d64;
-		    }
-		  else
-		    d = NULL;
-		}
-	      else
-		d = __readdir64 (stream);
+	      struct readdir_result d;
+	      {
+		if (__builtin_expect (flags & GLOB_ALTDIRFUNC, 0))
+		  d = convert_dirent (GL_READDIR (pglob, stream));
+		else
+		  {
+#ifdef COMPILE_GLOB64
+		    d = convert_dirent (__readdir (stream));
 #else
-	      struct dirent *d = (__builtin_expect (flags & GLOB_ALTDIRFUNC, 0)
-				  ? ((struct dirent *)
-				     (*pglob->gl_readdir) (stream))
-				  : __readdir (stream));
+		    d = convert_dirent64 (__readdir64 (stream));
 #endif
-	      if (d == NULL)
+		  }
+	      }
+	      if (d.name == NULL)
 		break;
-	      if (! REAL_DIR_ENTRY (d))
+	      if (d.skip_entry)
 		continue;
 
 	      /* If we shall match only directories use the information
 		 provided by the dirent call if possible.  */
-	      if ((flags & GLOB_ONLYDIR) && !DIRENT_MIGHT_BE_DIR (d))
+	      if ((flags & GLOB_ONLYDIR) && !readdir_result_might_be_dir (d))
 		continue;
 
-	      name = d->d_name;
-
-	      if (fnmatch (pattern, name, fnm_flags) == 0)
+	      if (fnmatch (pattern, d.name, fnm_flags) == 0)
 		{
 		  /* If the file we found is a symlink we have to
 		     make sure the target file exists.  */
-		  if (!DIRENT_MIGHT_BE_SYMLINK (d)
-		      || link_exists_p (dfd, directory, dirlen, name, pglob,
-					flags))
+		  if (!readdir_result_might_be_symlink (d)
+		      || link_exists_p (dfd, directory, dirlen, d.name,
+					pglob, flags))
 		    {
 		      if (cur == names->count)
 			{
@@ -1630,12 +1639,10 @@ glob_in_dir (const char *pattern, const char *directory, int flags,
 			  names = newnames;
 			  cur = 0;
 			}
-		      len = NAMLEN (d);
-		      names->name[cur] = (char *) malloc (len + 1);
+		      names->name[cur] = strdup (d.name);
 		      if (names->name[cur] == NULL)
 			goto memory_error;
-		      *((char *) mempcpy (names->name[cur++], name, len))
-			= '\0';
+		      ++cur;
 		      ++nfound;
 		    }
 		}
diff --git a/posix/tst-gnuglob.c b/posix/tst-gnuglob.c
index 1c72357de3..48c7527be8 100644
--- a/posix/tst-gnuglob.c
+++ b/posix/tst-gnuglob.c
@@ -211,7 +211,7 @@ my_readdir (void *gdir)
       return NULL;
     }
 
-  dir->d.d_ino = dir->idx;
+  dir->d.d_ino = 1;		/* glob should not skip this entry.  */
 
 #ifdef _DIRENT_HAVE_D_TYPE
   dir->d.d_type = filesystem[dir->idx].type;
diff --git a/resolv/nss_dns/dns-host.c b/resolv/nss_dns/dns-host.c
index f36d28bd70..63029d998e 100644
--- a/resolv/nss_dns/dns-host.c
+++ b/resolv/nss_dns/dns-host.c
@@ -1052,7 +1052,10 @@ gaih_getanswer_slice (const querybuf *answer, int anslen, const char *qname,
   int h_namelen = 0;
 
   if (ancount == 0)
-    return NSS_STATUS_NOTFOUND;
+    {
+      *h_errnop = HOST_NOT_FOUND;
+      return NSS_STATUS_NOTFOUND;
+    }
 
   while (ancount-- > 0 && cp < end_of_message && had_error == 0)
     {
@@ -1229,7 +1232,14 @@ gaih_getanswer_slice (const querybuf *answer, int anslen, const char *qname,
   /* Special case here: if the resolver sent a result but it only
      contains a CNAME while we are looking for a T_A or T_AAAA record,
      we fail with NOTFOUND instead of TRYAGAIN.  */
-  return canon == NULL ? NSS_STATUS_TRYAGAIN : NSS_STATUS_NOTFOUND;
+  if (canon != NULL)
+    {
+      *h_errnop = HOST_NOT_FOUND;
+      return NSS_STATUS_NOTFOUND;
+    }
+
+  *h_errnop = NETDB_INTERNAL;
+  return NSS_STATUS_TRYAGAIN;
 }
 
 
@@ -1243,11 +1253,101 @@ gaih_getanswer (const querybuf *answer1, int anslen1, const querybuf *answer2,
 
   enum nss_status status = NSS_STATUS_NOTFOUND;
 
+  /* Combining the NSS status of two distinct queries requires some
+     compromise and attention to symmetry (A or AAAA queries can be
+     returned in any order).  What follows is a breakdown of how this
+     code is expected to work and why. We discuss only SUCCESS,
+     TRYAGAIN, NOTFOUND and UNAVAIL, since they are the only returns
+     that apply (though RETURN and MERGE exist).  We make a distinction
+     between TRYAGAIN (recoverable) and TRYAGAIN' (not-recoverable).
+     A recoverable TRYAGAIN is almost always due to buffer size issues
+     and returns ERANGE in errno and the caller is expected to retry
+     with a larger buffer.
+
+     Lastly, you may be tempted to make significant changes to the
+     conditions in this code to bring about symmetry between responses.
+     Please don't change anything without due consideration for
+     expected application behaviour.  Some of the synthesized responses
+     aren't very well thought out and sometimes appear to imply that
+     IPv4 responses are always answer 1, and IPv6 responses are always
+     answer 2, but that's not true (see the implementation of send_dg
+     and send_vc to see response can arrive in any order, particularly
+     for UDP). However, we expect it holds roughly enough of the time
+     that this code works, but certainly needs to be fixed to make this
+     a more robust implementation.
+
+     ----------------------------------------------
+     | Answer 1 Status /   | Synthesized | Reason |
+     | Answer 2 Status     | Status      |        |
+     |--------------------------------------------|
+     | SUCCESS/SUCCESS     | SUCCESS     | [1]    |
+     | SUCCESS/TRYAGAIN    | TRYAGAIN    | [5]    |
+     | SUCCESS/TRYAGAIN'   | SUCCESS     | [1]    |
+     | SUCCESS/NOTFOUND    | SUCCESS     | [1]    |
+     | SUCCESS/UNAVAIL     | SUCCESS     | [1]    |
+     | TRYAGAIN/SUCCESS    | TRYAGAIN    | [2]    |
+     | TRYAGAIN/TRYAGAIN   | TRYAGAIN    | [2]    |
+     | TRYAGAIN/TRYAGAIN'  | TRYAGAIN    | [2]    |
+     | TRYAGAIN/NOTFOUND   | TRYAGAIN    | [2]    |
+     | TRYAGAIN/UNAVAIL    | TRYAGAIN    | [2]    |
+     | TRYAGAIN'/SUCCESS   | SUCCESS     | [3]    |
+     | TRYAGAIN'/TRYAGAIN  | TRYAGAIN    | [3]    |
+     | TRYAGAIN'/TRYAGAIN' | TRYAGAIN'   | [3]    |
+     | TRYAGAIN'/NOTFOUND  | TRYAGAIN'   | [3]    |
+     | TRYAGAIN'/UNAVAIL   | UNAVAIL     | [3]    |
+     | NOTFOUND/SUCCESS    | SUCCESS     | [3]    |
+     | NOTFOUND/TRYAGAIN   | TRYAGAIN    | [3]    |
+     | NOTFOUND/TRYAGAIN'  | TRYAGAIN'   | [3]    |
+     | NOTFOUND/NOTFOUND   | NOTFOUND    | [3]    |
+     | NOTFOUND/UNAVAIL    | UNAVAIL     | [3]    |
+     | UNAVAIL/SUCCESS     | UNAVAIL     | [4]    |
+     | UNAVAIL/TRYAGAIN    | UNAVAIL     | [4]    |
+     | UNAVAIL/TRYAGAIN'   | UNAVAIL     | [4]    |
+     | UNAVAIL/NOTFOUND    | UNAVAIL     | [4]    |
+     | UNAVAIL/UNAVAIL     | UNAVAIL     | [4]    |
+     ----------------------------------------------
+
+     [1] If the first response is a success we return success.
+	 This ignores the state of the second answer and in fact
+	 incorrectly sets errno and h_errno to that of the second
+	 answer.  However because the response is a success we ignore
+	 *errnop and *h_errnop (though that means you touched errno on
+	 success).  We are being conservative here and returning the
+	 likely IPv4 response in the first answer as a success.
+
+     [2] If the first response is a recoverable TRYAGAIN we return
+	 that instead of looking at the second response.  The
+	 expectation here is that we have failed to get an IPv4 response
+	 and should retry both queries.
+
+     [3] If the first response was not a SUCCESS and the second
+	 response is not NOTFOUND (had a SUCCESS, need to TRYAGAIN,
+	 or failed entirely e.g. TRYAGAIN' and UNAVAIL) then use the
+	 result from the second response, otherwise the first responses
+	 status is used.  Again we have some odd side-effects when the
+	 second response is NOTFOUND because we overwrite *errnop and
+	 *h_errnop that means that a first answer of NOTFOUND might see
+	 its *errnop and *h_errnop values altered.  Whether it matters
+	 in practice that a first response NOTFOUND has the wrong
+	 *errnop and *h_errnop is undecided.
+
+     [4] If the first response is UNAVAIL we return that instead of
+	 looking at the second response.  The expectation here is that
+	 it will have failed similarly e.g. configuration failure.
+
+     [5] Testing this code is complicated by the fact that truncated
+	 second response buffers might be returned as SUCCESS if the
+	 first answer is a SUCCESS.  To fix this we add symmetry to
+	 TRYAGAIN with the second response.  If the second response
+	 is a recoverable error we now return TRYAGIN even if the first
+	 response was SUCCESS.  */
+
   if (anslen1 > 0)
     status = gaih_getanswer_slice(answer1, anslen1, qname,
 				  &pat, &buffer, &buflen,
 				  errnop, h_errnop, ttlp,
 				  &first);
+
   if ((status == NSS_STATUS_SUCCESS || status == NSS_STATUS_NOTFOUND
        || (status == NSS_STATUS_TRYAGAIN
 	   /* We want to look at the second answer in case of an
@@ -1263,8 +1363,15 @@ gaih_getanswer (const querybuf *answer1, int anslen1, const querybuf *answer2,
 						     &pat, &buffer, &buflen,
 						     errnop, h_errnop, ttlp,
 						     &first);
+      /* Use the second response status in some cases.  */
       if (status != NSS_STATUS_SUCCESS && status2 != NSS_STATUS_NOTFOUND)
 	status = status2;
+      /* Do not return a truncated second response (unless it was
+	 unavoidable e.g. unrecoverable TRYAGAIN).  */
+      if (status == NSS_STATUS_SUCCESS
+	  && (status2 == NSS_STATUS_TRYAGAIN
+	      && *errnop == ERANGE && *h_errnop != NO_RECOVERY))
+	status = NSS_STATUS_TRYAGAIN;
     }
 
   return status;
diff --git a/resolv/nss_dns/dns-network.c b/resolv/nss_dns/dns-network.c
index 1993ec1676..539bb66b24 100644
--- a/resolv/nss_dns/dns-network.c
+++ b/resolv/nss_dns/dns-network.c
@@ -118,17 +118,14 @@ _nss_dns_getnetbyname_r (const char *name, struct netent *result,
   } net_buffer;
   querybuf *orig_net_buffer;
   int anslen;
-  char *qbuf;
   enum nss_status status;
 
   if (__res_maybe_init (&_res, 0) == -1)
     return NSS_STATUS_UNAVAIL;
 
-  qbuf = strdupa (name);
-
   net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024);
 
-  anslen = __libc_res_nsearch (&_res, qbuf, C_IN, T_PTR, net_buffer.buf->buf,
+  anslen = __libc_res_nsearch (&_res, name, C_IN, T_PTR, net_buffer.buf->buf,
 			       1024, &net_buffer.ptr, NULL, NULL, NULL, NULL);
   if (anslen < 0)
     {
diff --git a/resolv/res_query.c b/resolv/res_query.c
index c5c34026ef..6f5280df8e 100644
--- a/resolv/res_query.c
+++ b/resolv/res_query.c
@@ -394,6 +394,7 @@ __libc_res_nsearch(res_state statp,
 		  {
 		    free (*answerp2);
 		    *answerp2 = NULL;
+		    *nanswerp2 = 0;
 		    *answerp2_malloced = 0;
 		  }
 	}
@@ -433,6 +434,7 @@ __libc_res_nsearch(res_state statp,
 			  {
 			    free (*answerp2);
 			    *answerp2 = NULL;
+			    *nanswerp2 = 0;
 			    *answerp2_malloced = 0;
 			  }
 
@@ -506,6 +508,7 @@ __libc_res_nsearch(res_state statp,
 	  {
 	    free (*answerp2);
 	    *answerp2 = NULL;
+	    *nanswerp2 = 0;
 	    *answerp2_malloced = 0;
 	  }
 	if (saved_herrno != -1)
diff --git a/resolv/res_send.c b/resolv/res_send.c
index 416da8777e..11d0bbd1a2 100644
--- a/resolv/res_send.c
+++ b/resolv/res_send.c
@@ -1,3 +1,20 @@
+/* Copyright (C) 2016 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/>.  */
+
 /*
  * Copyright (c) 1985, 1989, 1993
  *    The Regents of the University of California.  All rights reserved.
@@ -360,6 +377,8 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
 #ifdef USE_HOOKS
 	if (__builtin_expect (statp->qhook || statp->rhook, 0)) {
 		if (anssiz < MAXPACKET && ansp) {
+			/* Always allocate MAXPACKET, callers expect
+			   this specific size.  */
 			u_char *buf = malloc (MAXPACKET);
 			if (buf == NULL)
 				return (-1);
@@ -653,6 +672,89 @@ libresolv_hidden_def (res_nsend)
 
 /* Private */
 
+/* Close the resolver structure, assign zero to *RESPLEN2 if RESPLEN2
+   is not NULL, and return zero.  */
+static int
+__attribute__ ((warn_unused_result))
+close_and_return_error (res_state statp, int *resplen2)
+{
+  __res_iclose(statp, false);
+  if (resplen2 != NULL)
+    *resplen2 = 0;
+  return 0;
+}
+
+/* The send_vc function is responsible for sending a DNS query over TCP
+   to the nameserver numbered NS from the res_state STATP i.e.
+   EXT(statp).nssocks[ns].  The function supports sending both IPv4 and
+   IPv6 queries at the same serially on the same socket.
+
+   Please note that for TCP there is no way to disable sending both
+   queries, unlike UDP, which honours RES_SNGLKUP and RES_SNGLKUPREOP
+   and sends the queries serially and waits for the result after each
+   sent query.  This implemetnation should be corrected to honour these
+   options.
+
+   Please also note that for TCP we send both queries over the same
+   socket one after another.  This technically violates best practice
+   since the server is allowed to read the first query, respond, and
+   then close the socket (to service another client).  If the server
+   does this, then the remaining second query in the socket data buffer
+   will cause the server to send the client an RST which will arrive
+   asynchronously and the client's OS will likely tear down the socket
+   receive buffer resulting in a potentially short read and lost
+   response data.  This will force the client to retry the query again,
+   and this process may repeat until all servers and connection resets
+   are exhausted and then the query will fail.  It's not known if this
+   happens with any frequency in real DNS server implementations.  This
+   implementation should be corrected to use two sockets by default for
+   parallel queries.
+
+   The query stored in BUF of BUFLEN length is sent first followed by
+   the query stored in BUF2 of BUFLEN2 length.  Queries are sent
+   serially on the same socket.
+
+   Answers to the query are stored firstly in *ANSP up to a max of
+   *ANSSIZP bytes.  If more than *ANSSIZP bytes are needed and ANSCP
+   is non-NULL (to indicate that modifying the answer buffer is allowed)
+   then malloc is used to allocate a new response buffer and ANSCP and
+   ANSP will both point to the new buffer.  If more than *ANSSIZP bytes
+   are needed but ANSCP is NULL, then as much of the response as
+   possible is read into the buffer, but the results will be truncated.
+   When truncation happens because of a small answer buffer the DNS
+   packets header feild TC will bet set to 1, indicating a truncated
+   message and the rest of the socket data will be read and discarded.
+
+   Answers to the query are stored secondly in *ANSP2 up to a max of
+   *ANSSIZP2 bytes, with the actual response length stored in
+   *RESPLEN2.  If more than *ANSSIZP bytes are needed and ANSP2
+   is non-NULL (required for a second query) then malloc is used to
+   allocate a new response buffer, *ANSSIZP2 is set to the new buffer
+   size and *ANSP2_MALLOCED is set to 1.
+
+   The ANSP2_MALLOCED argument will eventually be removed as the
+   change in buffer pointer can be used to detect the buffer has
+   changed and that the caller should use free on the new buffer.
+
+   Note that the answers may arrive in any order from the server and
+   therefore the first and second answer buffers may not correspond to
+   the first and second queries.
+
+   It is not supported to call this function with a non-NULL ANSP2
+   but a NULL ANSCP.  Put another way, you can call send_vc with a
+   single unmodifiable buffer or two modifiable buffers, but no other
+   combination is supported.
+
+   It is the caller's responsibility to free the malloc allocated
+   buffers by detecting that the pointers have changed from their
+   original values i.e. *ANSCP or *ANSP2 has changed.
+
+   If errors are encountered then *TERRNO is set to an appropriate
+   errno value and a zero result is returned for a recoverable error,
+   and a less-than zero result is returned for a non-recoverable error.
+
+   If no errors are encountered then *TERRNO is left unmodified and
+   a the length of the first response in bytes is returned.  */
 static int
 send_vc(res_state statp,
 	const u_char *buf, int buflen, const u_char *buf2, int buflen2,
@@ -662,11 +764,7 @@ send_vc(res_state statp,
 {
 	const HEADER *hp = (HEADER *) buf;
 	const HEADER *hp2 = (HEADER *) buf2;
-	u_char *ans = *ansp;
-	int orig_anssizp = *anssizp;
-	// XXX REMOVE
-	// int anssiz = *anssizp;
-	HEADER *anhp = (HEADER *) ans;
+	HEADER *anhp = (HEADER *) *ansp;
 	struct sockaddr_in6 *nsap = EXT(statp).nsaddrs[ns];
 	int truncating, connreset, resplen, n;
 	struct iovec iov[4];
@@ -742,6 +840,8 @@ send_vc(res_state statp,
 	 * Receive length & response
 	 */
 	int recvresp1 = 0;
+	/* Skip the second response if there is no second query.
+	   To do that we mark the second response as received.  */
 	int recvresp2 = buf2 == NULL;
 	uint16_t rlen16;
  read_len:
@@ -778,33 +878,14 @@ send_vc(res_state statp,
 	u_char **thisansp;
 	int *thisresplenp;
 	if ((recvresp1 | recvresp2) == 0 || buf2 == NULL) {
+		/* We have not received any responses
+		   yet or we only have one response to
+		   receive.  */
 		thisanssizp = anssizp;
 		thisansp = anscp ?: ansp;
 		assert (anscp != NULL || ansp2 == NULL);
 		thisresplenp = &resplen;
 	} else {
-		if (*anssizp != MAXPACKET) {
-			/* No buffer allocated for the first
-			   reply.  We can try to use the rest
-			   of the user-provided buffer.  */
-#ifdef _STRING_ARCH_unaligned
-			*anssizp2 = orig_anssizp - resplen;
-			*ansp2 = *ansp + resplen;
-#else
-			int aligned_resplen
-			  = ((resplen + __alignof__ (HEADER) - 1)
-			     & ~(__alignof__ (HEADER) - 1));
-			*anssizp2 = orig_anssizp - aligned_resplen;
-			*ansp2 = *ansp + aligned_resplen;
-#endif
-		} else {
-			/* The first reply did not fit into the
-			   user-provided buffer.  Maybe the second
-			   answer will.  */
-			*anssizp2 = orig_anssizp;
-			*ansp2 = *ansp;
-		}
-
 		thisanssizp = anssizp2;
 		thisansp = ansp2;
 		thisresplenp = resplen2;
@@ -812,10 +893,14 @@ send_vc(res_state statp,
 	anhp = (HEADER *) *thisansp;
 
 	*thisresplenp = rlen;
-	if (rlen > *thisanssizp) {
-		/* Yes, we test ANSCP here.  If we have two buffers
-		   both will be allocatable.  */
-		if (__builtin_expect (anscp != NULL, 1)) {
+	/* Is the answer buffer too small?  */
+	if (*thisanssizp < rlen) {
+		/* If the current buffer is non-NULL and it's not
+		   pointing at the static user-supplied buffer then
+		   we can reallocate it.  */
+		if (thisansp != NULL && thisansp != ansp) {
+			/* Always allocate MAXPACKET, callers expect
+			   this specific size.  */
 			u_char *newp = malloc (MAXPACKET);
 			if (newp == NULL) {
 				*terrno = ENOMEM;
@@ -827,6 +912,9 @@ send_vc(res_state statp,
 			if (thisansp == ansp2)
 			  *ansp2_malloced = 1;
 			anhp = (HEADER *) newp;
+			/* A uint16_t can't be larger than MAXPACKET
+			   thus it's safe to allocate MAXPACKET but
+			   read RLEN bytes instead.  */
 			len = rlen;
 		} else {
 			Dprint(statp->options & RES_DEBUG,
@@ -990,6 +1078,66 @@ reopen (res_state statp, int *terrno, int ns)
 	return 1;
 }
 
+/* The send_dg function is responsible for sending a DNS query over UDP
+   to the nameserver numbered NS from the res_state STATP i.e.
+   EXT(statp).nssocks[ns].  The function supports IPv4 and IPv6 queries
+   along with the ability to send the query in parallel for both stacks
+   (default) or serially (RES_SINGLKUP).  It also supports serial lookup
+   with a close and reopen of the socket used to talk to the server
+   (RES_SNGLKUPREOP) to work around broken name servers.
+
+   The query stored in BUF of BUFLEN length is sent first followed by
+   the query stored in BUF2 of BUFLEN2 length.  Queries are sent
+   in parallel (default) or serially (RES_SINGLKUP or RES_SNGLKUPREOP).
+
+   Answers to the query are stored firstly in *ANSP up to a max of
+   *ANSSIZP bytes.  If more than *ANSSIZP bytes are needed and ANSCP
+   is non-NULL (to indicate that modifying the answer buffer is allowed)
+   then malloc is used to allocate a new response buffer and ANSCP and
+   ANSP will both point to the new buffer.  If more than *ANSSIZP bytes
+   are needed but ANSCP is NULL, then as much of the response as
+   possible is read into the buffer, but the results will be truncated.
+   When truncation happens because of a small answer buffer the DNS
+   packets header feild TC will bet set to 1, indicating a truncated
+   message, while the rest of the UDP packet is discarded.
+
+   Answers to the query are stored secondly in *ANSP2 up to a max of
+   *ANSSIZP2 bytes, with the actual response length stored in
+   *RESPLEN2.  If more than *ANSSIZP bytes are needed and ANSP2
+   is non-NULL (required for a second query) then malloc is used to
+   allocate a new response buffer, *ANSSIZP2 is set to the new buffer
+   size and *ANSP2_MALLOCED is set to 1.
+
+   The ANSP2_MALLOCED argument will eventually be removed as the
+   change in buffer pointer can be used to detect the buffer has
+   changed and that the caller should use free on the new buffer.
+
+   Note that the answers may arrive in any order from the server and
+   therefore the first and second answer buffers may not correspond to
+   the first and second queries.
+
+   It is not supported to call this function with a non-NULL ANSP2
+   but a NULL ANSCP.  Put another way, you can call send_vc with a
+   single unmodifiable buffer or two modifiable buffers, but no other
+   combination is supported.
+
+   It is the caller's responsibility to free the malloc allocated
+   buffers by detecting that the pointers have changed from their
+   original values i.e. *ANSCP or *ANSP2 has changed.
+
+   If an answer is truncated because of UDP datagram DNS limits then
+   *V_CIRCUIT is set to 1 and the return value non-zero to indicate to
+   the caller to retry with TCP.  The value *GOTSOMEWHERE is set to 1
+   if any progress was made reading a response from the nameserver and
+   is used by the caller to distinguish between ECONNREFUSED and
+   ETIMEDOUT (the latter if *GOTSOMEWHERE is 1).
+
+   If errors are encountered then *TERRNO is set to an appropriate
+   errno value and a zero result is returned for a recoverable error,
+   and a less-than zero result is returned for a non-recoverable error.
+
+   If no errors are encountered then *TERRNO is left unmodified and
+   a the length of the first response in bytes is returned.  */
 static int
 send_dg(res_state statp,
 	const u_char *buf, int buflen, const u_char *buf2, int buflen2,
@@ -999,8 +1147,6 @@ send_dg(res_state statp,
 {
 	const HEADER *hp = (HEADER *) buf;
 	const HEADER *hp2 = (HEADER *) buf2;
-	u_char *ans = *ansp;
-	int orig_anssizp = *anssizp;
 	struct timespec now, timeout, finish;
 	struct pollfd pfd[1];
 	int ptimeout;
@@ -1025,7 +1171,11 @@ send_dg(res_state statp,
  retry_reopen:
 	retval = reopen (statp, terrno, ns);
 	if (retval <= 0)
-		return retval;
+	  {
+	    if (resplen2 != NULL)
+	      *resplen2 = 0;
+	    return retval;
+	  }
  retry:
 	evNowTime(&now);
 	evConsTime(&timeout, seconds, 0);
@@ -1033,11 +1183,11 @@ send_dg(res_state statp,
 	int need_recompute = 0;
 	int nwritten = 0;
 	int recvresp1 = 0;
+	/* Skip the second response if there is no second query.
+           To do that we mark the second response as received.  */
 	int recvresp2 = buf2 == NULL;
 	pfd[0].fd = EXT(statp).nssocks[ns];
 	pfd[0].events = POLLOUT;
-	if (resplen2 != NULL)
-	  *resplen2 = 0;
  wait:
 	if (need_recompute) {
 	recompute_resend:
@@ -1045,9 +1195,7 @@ send_dg(res_state statp,
 		if (evCmpTime(finish, now) <= 0) {
 		poll_err_out:
 			Perror(statp, stderr, "poll", errno);
-		err_out:
-			__res_iclose(statp, false);
-			return (0);
+			return close_and_return_error (statp, resplen2);
 		}
 		evSubTime(&timeout, &finish, &now);
 		need_recompute = 0;
@@ -1094,7 +1242,9 @@ send_dg(res_state statp,
 		  }
 
 		*gotsomewhere = 1;
-		return (0);
+		if (resplen2 != NULL)
+		  *resplen2 = 0;
+		return 0;
 	}
 	if (n < 0) {
 		if (errno == EINTR)
@@ -1162,7 +1312,7 @@ send_dg(res_state statp,
 
 		      fail_sendmmsg:
 			Perror(statp, stderr, "sendmmsg", errno);
-			goto err_out;
+			return close_and_return_error (statp, resplen2);
 		      }
 		  }
 		else
@@ -1180,7 +1330,7 @@ send_dg(res_state statp,
 		      if (errno == EINTR || errno == EAGAIN)
 			goto recompute_resend;
 		      Perror(statp, stderr, "send", errno);
-		      goto err_out;
+		      return close_and_return_error (statp, resplen2);
 		    }
 		  just_one:
 		    if (nwritten != 0 || buf2 == NULL || single_request)
@@ -1196,55 +1346,56 @@ send_dg(res_state statp,
 		int *thisresplenp;
 
 		if ((recvresp1 | recvresp2) == 0 || buf2 == NULL) {
+			/* We have not received any responses
+			   yet or we only have one response to
+			   receive.  */
 			thisanssizp = anssizp;
 			thisansp = anscp ?: ansp;
 			assert (anscp != NULL || ansp2 == NULL);
 			thisresplenp = &resplen;
 		} else {
-			if (*anssizp != MAXPACKET) {
-				/* No buffer allocated for the first
-				   reply.  We can try to use the rest
-				   of the user-provided buffer.  */
-#ifdef _STRING_ARCH_unaligned
-				*anssizp2 = orig_anssizp - resplen;
-				*ansp2 = *ansp + resplen;
-#else
-				int aligned_resplen
-				  = ((resplen + __alignof__ (HEADER) - 1)
-				     & ~(__alignof__ (HEADER) - 1));
-				*anssizp2 = orig_anssizp - aligned_resplen;
-				*ansp2 = *ansp + aligned_resplen;
-#endif
-			} else {
-				/* The first reply did not fit into the
-				   user-provided buffer.  Maybe the second
-				   answer will.  */
-				*anssizp2 = orig_anssizp;
-				*ansp2 = *ansp;
-			}
-
 			thisanssizp = anssizp2;
 			thisansp = ansp2;
 			thisresplenp = resplen2;
 		}
 
 		if (*thisanssizp < MAXPACKET
-		    /* Yes, we test ANSCP here.  If we have two buffers
-		       both will be allocatable.  */
-		    && anscp
+		    /* If the current buffer is non-NULL and it's not
+		       pointing at the static user-supplied buffer then
+		       we can reallocate it.  */
+		    && (thisansp != NULL && thisansp != ansp)
 #ifdef FIONREAD
+		    /* Is the size too small?  */
 		    && (ioctl (pfd[0].fd, FIONREAD, thisresplenp) < 0
 			|| *thisanssizp < *thisresplenp)
 #endif
                     ) {
+			/* Always allocate MAXPACKET, callers expect
+			   this specific size.  */
 			u_char *newp = malloc (MAXPACKET);
 			if (newp != NULL) {
-				*anssizp = MAXPACKET;
-				*thisansp = ans = newp;
+				*thisanssizp = MAXPACKET;
+				*thisansp = newp;
 				if (thisansp == ansp2)
 				  *ansp2_malloced = 1;
 			}
 		}
+		/* We could end up with truncation if anscp was NULL
+		   (not allowed to change caller's buffer) and the
+		   response buffer size is too small.  This isn't a
+		   reliable way to detect truncation because the ioctl
+		   may be an inaccurate report of the UDP message size.
+		   Therefore we use this only to issue debug output.
+		   To do truncation accurately with UDP we need
+		   MSG_TRUNC which is only available on Linux.  We
+		   can abstract out the Linux-specific feature in the
+		   future to detect truncation.  */
+		if (__glibc_unlikely (*thisanssizp < *thisresplenp)) {
+			Dprint(statp->options & RES_DEBUG,
+			       (stdout, ";; response may be truncated (UDP)\n")
+			);
+		}
+
 		HEADER *anhp = (HEADER *) *thisansp;
 		socklen_t fromlen = sizeof(struct sockaddr_in6);
 		assert (sizeof(from) <= fromlen);
@@ -1257,7 +1408,7 @@ send_dg(res_state statp,
 				goto wait;
 			}
 			Perror(statp, stderr, "recvfrom", errno);
-			goto err_out;
+			return close_and_return_error (statp, resplen2);
 		}
 		*gotsomewhere = 1;
 		if (__builtin_expect (*thisresplenp < HFIXEDSZ, 0)) {
@@ -1268,7 +1419,7 @@ send_dg(res_state statp,
 			       (stdout, ";; undersized: %d\n",
 				*thisresplenp));
 			*terrno = EMSGSIZE;
-			goto err_out;
+			return close_and_return_error (statp, resplen2);
 		}
 		if ((recvresp1 || hp->id != anhp->id)
 		    && (recvresp2 || hp2->id != anhp->id)) {
@@ -1317,7 +1468,7 @@ send_dg(res_state statp,
 				? *thisanssizp : *thisresplenp);
 			/* record the error */
 			statp->_flags |= RES_F_EDNS0ERR;
-			goto err_out;
+			return close_and_return_error (statp, resplen2);
 	}
 #endif
 		if (!(statp->options & RES_INSECURE2)
@@ -1369,10 +1520,10 @@ send_dg(res_state statp,
 			  }
 
 		next_ns:
-			__res_iclose(statp, false);
 			/* don't retry if called from dig */
 			if (!statp->pfcode)
-				return (0);
+			  return close_and_return_error (statp, resplen2);
+			__res_iclose(statp, false);
 		}
 		if (anhp->rcode == NOERROR && anhp->ancount == 0
 		    && anhp->aa == 0 && anhp->ra == 0 && anhp->arcount == 0) {
@@ -1394,6 +1545,8 @@ send_dg(res_state statp,
 			__res_iclose(statp, false);
 			// XXX if we have received one reply we could
 			// XXX use it and not repeat it over TCP...
+			if (resplen2 != NULL)
+			  *resplen2 = 0;
 			return (1);
 		}
 		/* Mark which reply we received.  */
@@ -1409,21 +1562,22 @@ send_dg(res_state statp,
 					__res_iclose (statp, false);
 					retval = reopen (statp, terrno, ns);
 					if (retval <= 0)
-						return retval;
+					  {
+					    if (resplen2 != NULL)
+					      *resplen2 = 0;
+					    return retval;
+					  }
 					pfd[0].fd = EXT(statp).nssocks[ns];
 				}
 			}
 			goto wait;
 		}
-		/*
-		 * All is well, or the error is fatal.  Signal that the
-		 * next nameserver ought not be tried.
-		 */
+		/* All is well.  We have received both responses (if
+		   two responses were requested).  */
 		return (resplen);
-	} else if (pfd[0].revents & (POLLERR | POLLHUP | POLLNVAL)) {
-		/* Something went wrong.  We can stop trying.  */
-		goto err_out;
-	}
+	} else if (pfd[0].revents & (POLLERR | POLLHUP | POLLNVAL))
+	  /* Something went wrong.  We can stop trying.  */
+	  return close_and_return_error (statp, resplen2);
 	else {
 		/* poll should not have returned > 0 in this case.  */
 		abort ();
diff --git a/stdlib/Makefile b/stdlib/Makefile
index 1be16eb8d0..8a34b838b6 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -64,11 +64,11 @@ test-srcs	:= tst-fmtmsg
 tests		:= tst-strtol tst-strtod testmb testrand testsort testdiv   \
 		   test-canon test-canon2 tst-strtoll tst-environ	    \
 		   tst-xpg-basename tst-random tst-random2 tst-bsearch	    \
-		   tst-limits tst-rand48 bug-strtod tst-setcontext	    \
-		   test-a64l tst-qsort tst-system testmb2 bug-strtod2	    \
-		   tst-atof1 tst-atof2 tst-strtod2 tst-strtod3 tst-rand48-2 \
-		   tst-makecontext tst-strtod4 tst-strtod5 tst-qsort2	    \
-		   tst-makecontext2 tst-strtod6 tst-unsetenv1		    \
+		   tst-limits tst-rand48 bug-strtod tst-setcontext          \
+		   tst-setcontext2 test-a64l tst-qsort tst-system testmb2   \
+		   bug-strtod2 tst-atof1 tst-atof2 tst-strtod2 tst-strtod3  \
+		   tst-rand48-2 tst-makecontext tst-strtod4 tst-strtod5     \
+		   tst-qsort2 tst-makecontext2 tst-strtod6 tst-unsetenv1    \
 		   tst-makecontext3 bug-getcontext bug-fmtmsg1		    \
 		   tst-secure-getenv tst-strtod-overflow tst-strtod-round   \
 		   tst-tininess tst-strtod-underflow tst-tls-atexit
@@ -164,3 +164,5 @@ tst-tls-atexit-lib.so-no-z-defs = yes
 $(objpfx)tst-tls-atexit: $(common-objpfx)nptl/libpthread.so \
 			 $(common-objpfx)dlfcn/libdl.so
 $(objpfx)tst-tls-atexit.out: $(objpfx)tst-tls-atexit-lib.so
+
+$(objpfx)tst-makecontext: $(libdl)
diff --git a/stdlib/cxa_thread_atexit_impl.c b/stdlib/cxa_thread_atexit_impl.c
index d2f88d3ed8..6030e5fc6f 100644
--- a/stdlib/cxa_thread_atexit_impl.c
+++ b/stdlib/cxa_thread_atexit_impl.c
@@ -42,6 +42,10 @@ static __thread struct link_map *lm_cache;
 int
 __cxa_thread_atexit_impl (dtor_func func, void *obj, void *dso_symbol)
 {
+#ifdef PTR_MANGLE
+  PTR_MANGLE (func);
+#endif
+
   /* Prepend.  */
   struct dtor_list *new = calloc (1, sizeof (struct dtor_list));
   new->func = func;
@@ -83,9 +87,13 @@ __call_tls_dtors (void)
   while (tls_dtor_list)
     {
       struct dtor_list *cur = tls_dtor_list;
-      tls_dtor_list = tls_dtor_list->next;
+      dtor_func func = cur->func;
+#ifdef PTR_DEMANGLE
+      PTR_DEMANGLE (func);
+#endif
 
-      cur->func (cur->obj);
+      tls_dtor_list = tls_dtor_list->next;
+      func (cur->obj);
 
       __rtld_lock_lock_recursive (GL(dl_load_lock));
 
diff --git a/stdlib/tst-makecontext.c b/stdlib/tst-makecontext.c
index 7968a6d3dc..ef1e27a634 100644
--- a/stdlib/tst-makecontext.c
+++ b/stdlib/tst-makecontext.c
@@ -19,23 +19,62 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <ucontext.h>
+#include <assert.h>
+#include <unwind.h>
+#include <dlfcn.h>
+#include <gnu/lib-names.h>
 
 ucontext_t ucp;
-char st1[8192];
+char st1[16384];
 __thread int thr;
 
 int somevar = -76;
 long othervar = -78L;
 
+struct trace_arg
+{
+  int cnt, size;
+};
+
+static _Unwind_Reason_Code
+backtrace_helper (struct _Unwind_Context *ctx, void *a)
+{
+  struct trace_arg *arg = a;
+  if (++arg->cnt == arg->size)
+    return _URC_END_OF_STACK;
+  return _URC_NO_REASON;
+}
+
 void
 cf (int i)
 {
+  struct trace_arg arg = { .size = 100, .cnt = -1 };
+  void *handle;
+  _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *);
+
   if (i != othervar || thr != 94)
     {
       printf ("i %d thr %d\n", i, thr);
       exit (1);
     }
 
+  /* Test if callback function of _Unwind_Backtrace is not called infinitely
+     times. See Bug 18508 or gcc bug "Bug 66303 - runtime.Caller() returns
+     infinitely deep stack frames on s390x.".
+     The go runtime calls backtrace_full() in
+     <gcc-src>/libbacktrace/backtrace.c, which uses _Unwind_Backtrace().  */
+  handle = dlopen (LIBGCC_S_SO, RTLD_LAZY);
+  if (handle != NULL)
+    {
+      unwind_backtrace = dlsym (handle, "_Unwind_Backtrace");
+      if (unwind_backtrace != NULL)
+	{
+	  unwind_backtrace (backtrace_helper, &arg);
+	  assert (arg.cnt != -1 && arg.cnt < 100);
+	}
+      dlclose (handle);
+    }
+
   /* Since uc_link below has been set to NULL, setcontext is supposed to
      terminate the process normally after this function returns.  */
 }
diff --git a/stdlib/tst-setcontext2.c b/stdlib/tst-setcontext2.c
new file mode 100644
index 0000000000..8582cc0c1c
--- /dev/null
+++ b/stdlib/tst-setcontext2.c
@@ -0,0 +1,230 @@
+/* Testcase checks, if setcontext(), swapcontext() restores signal-mask
+   and if pending signals are delivered after those calls.
+   Copyright (C) 2015 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 <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <ucontext.h>
+#include <unistd.h>
+
+volatile int global;
+volatile sig_atomic_t handlerCalled;
+
+static void
+check (const char *funcName)
+{
+  sigset_t set;
+
+  /* check if SIGUSR2 is unblocked after setcontext-call.  */
+  sigprocmask (SIG_BLOCK, NULL, &set);
+
+  if (sigismember (&set, SIGUSR2) != 0)
+    {
+      printf ("FAIL: SIGUSR2 is blocked after %s.\n", funcName);
+      exit (1);
+    }
+
+  if (sigismember (&set, SIGUSR1) != 1)
+    {
+      printf ("FAIL: SIGUSR1 is not blocked after %s.\n", funcName);
+      exit (1);
+    }
+}
+
+static void
+signalmask (int how, int signum)
+{
+  sigset_t set;
+  sigemptyset (&set);
+  sigaddset (&set, signum);
+  if (sigprocmask (how, &set, NULL) != 0)
+    {
+      printf ("FAIL: sigprocmaks (%d, %d, NULL): %m\n", how, signum);
+      exit (1);
+    }
+}
+
+static void
+signalpending (int signum, const char *msg)
+{
+  sigset_t set;
+  sigemptyset (&set);
+  if (sigpending (&set) != 0)
+    {
+      printf ("FAIL: sigpending: %m\n");
+      exit (1);
+    }
+  if (sigismember (&set, SIGUSR2) != 1)
+    {
+      printf ("FAIL: Signal %d is not pending %s\n", signum, msg);
+      exit (1);
+    }
+}
+
+static void
+handler (int __attribute__ ((unused)) signum)
+{
+  handlerCalled ++;
+}
+
+static int
+do_test (void)
+{
+  ucontext_t ctx, oldctx;
+  struct sigaction action;
+  pid_t pid;
+
+  pid = getpid ();
+
+  /* unblock SIGUSR2 */
+  signalmask (SIG_UNBLOCK, SIGUSR2);
+
+  /* block SIGUSR1 */
+  signalmask (SIG_BLOCK, SIGUSR1);
+
+  /* register handler for SIGUSR2  */
+  action.sa_flags = 0;
+  action.sa_handler = handler;
+  sigemptyset (&action.sa_mask);
+  sigaction (SIGUSR2, &action, NULL);
+
+  if (getcontext (&ctx) != 0)
+    {
+      printf ("FAIL: getcontext: %m\n");
+      exit (1);
+    }
+
+  global++;
+
+  if (global == 1)
+    {
+      puts ("after getcontext");
+
+      /* block SIGUSR2  */
+      signalmask (SIG_BLOCK, SIGUSR2);
+
+      /* send SIGUSR2 to me  */
+      handlerCalled = 0;
+      kill (pid, SIGUSR2);
+
+      /* was SIGUSR2 handler called?  */
+      if (handlerCalled != 0)
+	{
+	  puts ("FAIL: signal handler was called, but signal was blocked.");
+	  exit (1);
+	}
+
+      /* is SIGUSR2 pending?  */
+      signalpending (SIGUSR2, "before setcontext");
+
+      /* SIGUSR2 will be unblocked by setcontext-call.  */
+      if (setcontext (&ctx) != 0)
+	{
+	  printf ("FAIL: setcontext: %m\n");
+	  exit (1);
+	}
+    }
+  else if (global == 2)
+    {
+      puts ("after setcontext");
+
+      /* check SIGUSR1/2  */
+      check ("setcontext");
+
+      /* was SIGUSR2 handler called? */
+      if (handlerCalled != 1)
+	{
+	  puts ("FAIL: signal handler was not called after setcontext.");
+	  exit (1);
+	}
+
+      /* block SIGUSR2 */
+      signalmask (SIG_BLOCK, SIGUSR2);
+
+      /* send SIGUSR2 to me  */
+      handlerCalled = 0;
+      kill (pid, SIGUSR2);
+
+      /* was SIGUSR2 handler called?  */
+      if (handlerCalled != 0)
+	{
+	  puts ("FAIL: signal handler was called, but signal was blocked.");
+	  exit (1);
+	}
+
+      /* is SIGUSR2 pending?  */
+      signalpending (SIGUSR2, "before swapcontext");
+
+      if (swapcontext (&oldctx, &ctx) != 0)
+	{
+	  printf ("FAIL: swapcontext: %m\n");
+	  exit (1);
+	}
+
+      puts ("after returned from swapcontext");
+
+      if (global != 3)
+	{
+	  puts ("FAIL: returned from swapcontext without ctx-context called.");
+	  exit (1);
+	}
+
+      puts ("test succeeded");
+      return 0;
+    }
+  else if ( global != 3 )
+    {
+      puts ("FAIL: 'global' not incremented three times");
+      exit (1);
+    }
+
+  puts ("after swapcontext");
+  /* check SIGUSR1/2  */
+  check ("swapcontext");
+
+  /* was SIGUSR2 handler called? */
+  if (handlerCalled != 1)
+    {
+      puts ("FAIL: signal handler was not called after swapcontext.");
+      exit (1);
+    }
+
+  /* check sigmask in old context of swapcontext-call  */
+  if (sigismember (&oldctx.uc_sigmask, SIGUSR2) != 1)
+    {
+      puts ("FAIL: SIGUSR2 is not blocked in oldctx.uc_sigmask.");
+      exit (1);
+    }
+
+  if (sigismember (&oldctx.uc_sigmask, SIGUSR1) != 1)
+    {
+      puts ("FAIL: SIGUSR1 is not blocked in oldctx.uc_sigmaks.");
+      exit (1);
+    }
+
+  /* change to old context, which was gathered by swapcontext() call.  */
+  setcontext (&oldctx);
+
+  puts ("FAIL: returned from setcontext (&oldctx)");
+  exit (1);
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/string/strxfrm_l.c b/string/strxfrm_l.c
index 04b9338f05..e496550f92 100644
--- a/string/strxfrm_l.c
+++ b/string/strxfrm_l.c
@@ -40,8 +40,23 @@
 #define CONCAT(a,b) CONCAT1(a,b)
 #define CONCAT1(a,b) a##b
 
+/* Maximum string size that is calculated with cached indices.  Right now this
+   is an arbitrary value open to optimizations.  SMALL_STR_SIZE * 4 has to be
+   lower than __MAX_ALLOCA_CUTOFF.  Keep localedata/xfrm-test.c in sync.  */
+#define SMALL_STR_SIZE 4095
+
 #include "../locale/localeinfo.h"
 
+/* Group locale data for shorter parameter lists.  */
+typedef struct
+{
+  uint_fast32_t nrules;
+  unsigned char *rulesets;
+  USTRING_TYPE *weights;
+  int32_t *table;
+  USTRING_TYPE *extra;
+  int32_t *indirect;
+} locale_data_t;
 
 #ifndef WIDE_CHAR_VERSION
 
@@ -80,115 +95,330 @@ utf8_encode (char *buf, int val)
 }
 #endif
 
-
-size_t
-STRXFRM (STRING_TYPE *dest, const STRING_TYPE *src, size_t n, __locale_t l)
+/* Find next weight and rule index.  Inlined since called for every char.  */
+static __always_inline size_t
+find_idx (const USTRING_TYPE **us, int32_t *weight_idx,
+	  unsigned char *rule_idx, const locale_data_t *l_data, const int pass)
 {
-  struct __locale_data *current = l->__locales[LC_COLLATE];
-  uint_fast32_t nrules = current->values[_NL_ITEM_INDEX (_NL_COLLATE_NRULES)].word;
-  /* We don't assign the following values right away since it might be
-     unnecessary in case there are no rules.  */
-  const unsigned char *rulesets;
-  const int32_t *table;
-  const USTRING_TYPE *weights;
-  const USTRING_TYPE *extra;
-  const int32_t *indirect;
-  uint_fast32_t pass;
-  size_t needed;
-  size_t last_needed;
-  const USTRING_TYPE *usrc;
-  size_t srclen = STRLEN (src);
-  int32_t *idxarr;
-  unsigned char *rulearr;
-  size_t idxmax;
-  size_t idxcnt;
-  int use_malloc;
+  /* Prepare variables required by findidx().  */
+  int32_t *table = l_data->table;
+  int32_t *indirect = l_data->indirect;
+  USTRING_TYPE *extra = l_data->extra;
 
 #include WEIGHT_H
+  int32_t tmp = findidx (us, -1);
+  *rule_idx = tmp >> 24;
+  int32_t idx = tmp & 0xffffff;
+  size_t len = l_data->weights[idx++];
 
-  if (nrules == 0)
+  /* Skip over indices of previous levels.  */
+  for (int i = 0; i < pass; i++)
     {
-      if (n != 0)
-	STPNCPY (dest, src, MIN (srclen + 1, n));
-
-      return srclen;
+      idx += len;
+      len = l_data->weights[idx++];
     }
 
-  rulesets = (const unsigned char *)
-    current->values[_NL_ITEM_INDEX (_NL_COLLATE_RULESETS)].string;
-  table = (const int32_t *)
-    current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_TABLE,SUFFIX))].string;
-  weights = (const USTRING_TYPE *)
-    current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_WEIGHT,SUFFIX))].string;
-  extra = (const USTRING_TYPE *)
-    current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_EXTRA,SUFFIX))].string;
-  indirect = (const int32_t *)
-    current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_INDIRECT,SUFFIX))].string;
-  use_malloc = 0;
+  *weight_idx = idx;
+  return len;
+}
 
-  assert (((uintptr_t) table) % __alignof__ (table[0]) == 0);
-  assert (((uintptr_t) weights) % __alignof__ (weights[0]) == 0);
-  assert (((uintptr_t) extra) % __alignof__ (extra[0]) == 0);
-  assert (((uintptr_t) indirect) % __alignof__ (indirect[0]) == 0);
+static int
+find_position (const USTRING_TYPE *us, const locale_data_t *l_data,
+	       const int pass)
+{
+  int32_t weight_idx;
+  unsigned char rule_idx;
+  const USTRING_TYPE *usrc = us;
 
-  /* Handle an empty string as a special case.  */
-  if (srclen == 0)
-    {
-      if (n != 0)
-	*dest = L('\0');
-      return 0;
-    }
+  find_idx (&usrc, &weight_idx, &rule_idx, l_data, pass);
+  return l_data->rulesets[rule_idx * l_data->nrules + pass] & sort_position;
+}
 
-  /* We need the elements of the string as unsigned values since they
-     are used as indeces.  */
-  usrc = (const USTRING_TYPE *) src;
-
-  /* Perform the first pass over the string and while doing this find
-     and store the weights for each character.  Since we want this to
-     be as fast as possible we are using `alloca' to store the temporary
-     values.  But since there is no limit on the length of the string
-     we have to use `malloc' if the string is too long.  We should be
-     very conservative here.  */
-  if (! __libc_use_alloca ((srclen + 1) * (sizeof (int32_t) + 1)))
-    {
-      idxarr = (int32_t *) malloc ((srclen + 1) * (sizeof (int32_t) + 1));
-      rulearr = (unsigned char *) &idxarr[srclen];
-
-      if (idxarr == NULL)
-	/* No memory.  Well, go with the stack then.
-
-	   XXX Once this implementation is stable we will handle this
-	   differently.  Instead of precomputing the indeces we will
-	   do this in time.  This means, though, that this happens for
-	   every pass again.  */
-	goto try_stack;
-      use_malloc = 1;
-    }
-  else
+/* Do the transformation.  */
+static size_t
+do_xfrm (const USTRING_TYPE *usrc, STRING_TYPE *dest, size_t n,
+	 const locale_data_t *l_data)
+{
+  int32_t weight_idx;
+  unsigned char rule_idx;
+  uint_fast32_t pass;
+  size_t needed = 0;
+  size_t last_needed;
+
+  /* Now the passes over the weights.  */
+  for (pass = 0; pass < l_data->nrules; ++pass)
     {
-    try_stack:
-      idxarr = (int32_t *) alloca (srclen * sizeof (int32_t));
-      rulearr = (unsigned char *) alloca (srclen + 1);
+      size_t backw_len = 0;
+      last_needed = needed;
+      const USTRING_TYPE *cur = usrc;
+      const USTRING_TYPE *backw_start = NULL;
+
+       /* We assume that if a rule has defined `position' in one section
+         this is true for all of them.  */
+      int position = find_position (cur, l_data, pass);
+
+      if (position == 0)
+	{
+	  while (*cur != L('\0'))
+	    {
+	      const USTRING_TYPE *pos = cur;
+	      size_t len = find_idx (&cur, &weight_idx, &rule_idx, l_data,
+				     pass);
+	      int rule = l_data->rulesets[rule_idx * l_data->nrules + pass];
+
+	      if ((rule & sort_forward) != 0)
+		{
+		  /* Handle the pushed backward sequence.  */
+		  if (backw_start != NULL)
+		    {
+		      for (size_t i = backw_len; i > 0; )
+			{
+			  int32_t weight_idx;
+			  unsigned char rule_idx;
+			  size_t len = find_idx (&backw_start, &weight_idx,
+						 &rule_idx, l_data, pass);
+			  if (needed + i < n)
+			    for (size_t j = len; j > 0; j--)
+			      dest[needed + i - j] =
+				l_data->weights[weight_idx++];
+
+			  i -= len;
+			}
+
+		      needed += backw_len;
+		      backw_start = NULL;
+		      backw_len = 0;
+		    }
+
+		  /* Now handle the forward element.  */
+		  if (needed + len < n)
+		    while (len-- > 0)
+		      dest[needed++] = l_data->weights[weight_idx++];
+		  else
+		    /* No more characters fit into the buffer.  */
+		    needed += len;
+		}
+	      else
+		{
+		  /* Remember start of the backward sequence & track length.  */
+		  if (backw_start == NULL)
+		    backw_start = pos;
+		  backw_len += len;
+		}
+	    }
+
+
+	  /* Handle the pushed backward sequence.  */
+	  if (backw_start != NULL)
+	    {
+	      for (size_t i = backw_len; i > 0; )
+		{
+		  size_t len = find_idx (&backw_start, &weight_idx, &rule_idx,
+					 l_data, pass);
+		  if (needed + i < n)
+		    for (size_t j = len; j > 0; j--)
+		      dest[needed + i - j] =
+			l_data->weights[weight_idx++];
+
+		  i -= len;
+		}
+
+	      needed += backw_len;
+	    }
+	}
+      else
+	{
+	  int val = 1;
+#ifndef WIDE_CHAR_VERSION
+	  char buf[7];
+	  size_t buflen;
+#endif
+	  size_t i;
+
+	  while (*cur != L('\0'))
+	    {
+	      const USTRING_TYPE *pos = cur;
+	      size_t len = find_idx (&cur, &weight_idx, &rule_idx, l_data,
+				     pass);
+	      int rule = l_data->rulesets[rule_idx * l_data->nrules + pass];
+
+	      if ((rule & sort_forward) != 0)
+		{
+		  /* Handle the pushed backward sequence.  */
+		  if (backw_start != NULL)
+		    {
+		      for (size_t p = backw_len; p > 0; p--)
+			{
+			  size_t len;
+			  int32_t weight_idx;
+			  unsigned char rule_idx;
+			  const USTRING_TYPE *backw_cur = backw_start;
+
+			  /* To prevent a warning init the used vars.  */
+			  len = find_idx (&backw_cur, &weight_idx,
+					  &rule_idx, l_data, pass);
+
+			  for (i = 1; i < p; i++)
+			    len = find_idx (&backw_cur, &weight_idx,
+					    &rule_idx, l_data, pass);
+
+			  if (len != 0)
+			    {
+#ifdef WIDE_CHAR_VERSION
+			      if (needed + 1 + len < n)
+				{
+				  dest[needed] = val;
+				  for (i = 0; i < len; ++i)
+				    dest[needed + 1 + i] =
+				      l_data->weights[weight_idx + i];
+				}
+			      needed += 1 + len;
+#else
+			      buflen = utf8_encode (buf, val);
+			      if (needed + buflen + len < n)
+				{
+				  for (i = 0; i < buflen; ++i)
+				    dest[needed + i] = buf[i];
+				  for (i = 0; i < len; ++i)
+				    dest[needed + buflen + i] =
+				      l_data->weights[weight_idx + i];
+				}
+			      needed += buflen + len;
+#endif
+			      val = 1;
+			    }
+			  else
+			    ++val;
+			}
+
+		      backw_start = NULL;
+		      backw_len = 0;
+		    }
+
+		  /* Now handle the forward element.  */
+		  if (len != 0)
+		    {
+#ifdef WIDE_CHAR_VERSION
+		      if (needed + 1 + len < n)
+			{
+			  dest[needed] = val;
+			  for (i = 0; i < len; ++i)
+			    dest[needed + 1 + i] =
+			      l_data->weights[weight_idx + i];
+			}
+		      needed += 1 + len;
+#else
+		      buflen = utf8_encode (buf, val);
+		      if (needed + buflen + len < n)
+			{
+			  for (i = 0; i < buflen; ++i)
+			    dest[needed + i] = buf[i];
+			  for (i = 0; i < len; ++i)
+			    dest[needed + buflen + i] =
+			      l_data->weights[weight_idx + i];
+			}
+		      needed += buflen + len;
+#endif
+		      val = 1;
+		    }
+		  else
+		    ++val;
+		}
+	      else
+		{
+		  /* Remember start of the backward sequence & track length.  */
+		  if (backw_start == NULL)
+		    backw_start = pos;
+		  backw_len++;
+		}
+	    }
+
+	  /* Handle the pushed backward sequence.  */
+	  if (backw_start != NULL)
+	    {
+	      for (size_t p = backw_len; p > 0; p--)
+		{
+		  size_t len;
+		  int32_t weight_idx;
+		  unsigned char rule_idx;
+		  const USTRING_TYPE *backw_cur = backw_start;
+
+		  /* To prevent a warning init the used vars.  */
+		  len = find_idx (&backw_cur, &weight_idx,
+				  &rule_idx, l_data, pass);
+
+		  for (i = 1; i < p; i++)
+		    len = find_idx (&backw_cur, &weight_idx,
+				    &rule_idx, l_data, pass);
+
+		  if (len != 0)
+		    {
+#ifdef WIDE_CHAR_VERSION
+		      if (needed + 1 + len < n)
+			{
+			  dest[needed] = val;
+			  for (i = 0; i < len; ++i)
+			    dest[needed + 1 + i] =
+			      l_data->weights[weight_idx + i];
+			}
+		      needed += 1 + len;
+#else
+		      buflen = utf8_encode (buf, val);
+		      if (needed + buflen + len < n)
+			{
+			  for (i = 0; i < buflen; ++i)
+			    dest[needed + i] = buf[i];
+			  for (i = 0; i < len; ++i)
+			    dest[needed + buflen + i] =
+			      l_data->weights[weight_idx + i];
+			}
+		      needed += buflen + len;
+#endif
+		      val = 1;
+		    }
+		  else
+		    ++val;
+		}
+	    }
+	}
+
+      /* Finally store the byte to separate the passes or terminate
+	 the string.  */
+      if (needed < n)
+	dest[needed] = pass + 1 < l_data->nrules ? L('\1') : L('\0');
+      ++needed;
     }
 
-  idxmax = 0;
-  do
+  /* This is a little optimization: many collation specifications have
+     a `position' rule at the end and if no non-ignored character
+     is found the last \1 byte is immediately followed by a \0 byte
+     signalling this.  We can avoid the \1 byte(s).  */
+  if (needed > 2 && needed == last_needed + 1)
     {
-      int32_t tmp = findidx (&usrc, -1);
-      rulearr[idxmax] = tmp >> 24;
-      idxarr[idxmax] = tmp & 0xffffff;
-
-      ++idxmax;
+      /* Remove the \1 byte.  */
+      if (--needed <= n)
+	dest[needed - 1] = L('\0');
     }
-  while (*usrc != L('\0'));
 
-  /* This element is only read, the value never used but to determine
-     another value which then is ignored.  */
-  rulearr[idxmax] = '\0';
+  /* Return the number of bytes/words we need, but don't count the NUL
+     byte/word at the end.  */
+  return needed - 1;
+}
+
+/* Do the transformation using weight-index and rule cache.  */
+static size_t
+do_xfrm_cached (STRING_TYPE *dest, size_t n, const locale_data_t *l_data,
+		size_t idxmax, int32_t *idxarr, const unsigned char *rulearr)
+{
+  uint_fast32_t nrules = l_data->nrules;
+  unsigned char *rulesets = l_data->rulesets;
+  USTRING_TYPE *weights = l_data->weights;
+  uint_fast32_t pass;
+  size_t needed = 0;
+  size_t last_needed;
+  size_t idxcnt;
 
-  /* Now the passes over the weights.  We now use the indeces we found
-     before.  */
-  needed = 0;
+  /* Now the passes over the weights.  */
   for (pass = 0; pass < nrules; ++pass)
     {
       size_t backw_stop = ~0ul;
@@ -434,14 +664,91 @@ STRXFRM (STRING_TYPE *dest, const STRING_TYPE *src, size_t n, __locale_t l)
 	dest[needed - 1] = L('\0');
     }
 
-  /* Free the memory if needed.  */
-  if (use_malloc)
-    free (idxarr);
-
   /* Return the number of bytes/words we need, but don't count the NUL
      byte/word at the end.  */
   return needed - 1;
 }
+
+size_t
+STRXFRM (STRING_TYPE *dest, const STRING_TYPE *src, size_t n, __locale_t l)
+{
+  locale_data_t l_data;
+  struct __locale_data *current = l->__locales[LC_COLLATE];
+  l_data.nrules = current->values[_NL_ITEM_INDEX (_NL_COLLATE_NRULES)].word;
+
+  /* Handle byte comparison case.  */
+  if (l_data.nrules == 0)
+    {
+      size_t srclen = STRLEN (src);
+
+      if (n != 0)
+	STPNCPY (dest, src, MIN (srclen + 1, n));
+
+      return srclen;
+    }
+
+  /* Handle an empty string, code hereafter relies on strlen (src) > 0.  */
+  if (*src == L('\0'))
+    {
+      if (n != 0)
+	*dest = L('\0');
+      return 0;
+    }
+
+  /* Get the locale data.  */
+  l_data.rulesets = (unsigned char *)
+    current->values[_NL_ITEM_INDEX (_NL_COLLATE_RULESETS)].string;
+  l_data.table = (int32_t *)
+    current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_TABLE,SUFFIX))].string;
+  l_data.weights = (USTRING_TYPE *)
+    current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_WEIGHT,SUFFIX))].string;
+  l_data.extra = (USTRING_TYPE *)
+    current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_EXTRA,SUFFIX))].string;
+  l_data.indirect = (int32_t *)
+    current->values[_NL_ITEM_INDEX (CONCAT(_NL_COLLATE_INDIRECT,SUFFIX))].string;
+
+  assert (((uintptr_t) l_data.table) % __alignof__ (l_data.table[0]) == 0);
+  assert (((uintptr_t) l_data.weights) % __alignof__ (l_data.weights[0]) == 0);
+  assert (((uintptr_t) l_data.extra) % __alignof__ (l_data.extra[0]) == 0);
+  assert (((uintptr_t) l_data.indirect) % __alignof__ (l_data.indirect[0]) == 0);
+
+  /* We need the elements of the string as unsigned values since they
+     are used as indeces.  */
+  const USTRING_TYPE *usrc = (const USTRING_TYPE *) src;
+
+  /* Allocate cache for small strings on the stack and fill it with weight and
+     rule indices.  If the cache size is not sufficient, continue with the
+     uncached xfrm version.  */
+  size_t idxmax = 0;
+  const USTRING_TYPE *cur = usrc;
+  int32_t *idxarr = alloca (SMALL_STR_SIZE * sizeof (int32_t));
+  unsigned char *rulearr = alloca (SMALL_STR_SIZE + 1);
+  /* Prepare variables required by findidx().  */
+  int32_t *table = l_data.table;
+  int32_t *indirect = l_data.indirect;
+  USTRING_TYPE *extra = l_data.extra;
+#include WEIGHT_H
+
+  do
+    {
+      int32_t tmp = findidx (&cur, -1);
+      rulearr[idxmax] = tmp >> 24;
+      idxarr[idxmax] = tmp & 0xffffff;
+
+      ++idxmax;
+    }
+  while (*cur != L('\0') && idxmax < SMALL_STR_SIZE);
+
+  /* This element is only read, the value never used but to determine
+     another value which then is ignored.  */
+  rulearr[idxmax] = '\0';
+
+  /* Do the transformation.  */
+  if (*cur == L('\0'))
+    return do_xfrm_cached (dest, n, &l_data, idxmax, idxarr, rulearr);
+  else
+    return do_xfrm (usrc, dest, n, &l_data);
+}
 libc_hidden_def (STRXFRM)
 
 #ifndef WIDE_CHAR_VERSION
diff --git a/sunrpc/clnt_udp.c b/sunrpc/clnt_udp.c
index 1b6a20b826..81d5637cd7 100644
--- a/sunrpc/clnt_udp.c
+++ b/sunrpc/clnt_udp.c
@@ -420,9 +420,15 @@ send_again:
 	  struct sock_extended_err *e;
 	  struct sockaddr_in err_addr;
 	  struct iovec iov;
-	  char *cbuf = (char *) alloca (outlen + 256);
+	  char *cbuf = malloc (outlen + 256);
 	  int ret;
 
+	  if (cbuf == NULL)
+	    {
+	      cu->cu_error.re_errno = errno;
+	      return (cu->cu_error.re_status = RPC_CANTRECV);
+	    }
+
 	  iov.iov_base = cbuf + 256;
 	  iov.iov_len = outlen;
 	  msg.msg_name = (void *) &err_addr;
@@ -447,10 +453,12 @@ send_again:
 		 cmsg = CMSG_NXTHDR (&msg, cmsg))
 	      if (cmsg->cmsg_level == SOL_IP && cmsg->cmsg_type == IP_RECVERR)
 		{
+		  free (cbuf);
 		  e = (struct sock_extended_err *) CMSG_DATA(cmsg);
 		  cu->cu_error.re_errno = e->ee_errno;
 		  return (cu->cu_error.re_status = RPC_CANTRECV);
 		}
+	  free (cbuf);
 	}
 #endif
       do
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index ffeb093887..9d767b64d2 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -590,9 +590,6 @@ struct rtld_global_ro
   /* List of auditing interfaces.  */
   struct audit_ifaces *_dl_audit;
   unsigned int _dl_naudit;
-
-  /* 0 if internal pointer values should not be guarded, 1 if they should.  */
-  EXTERN int _dl_pointer_guard;
 };
 # define __rtld_global_attribute__
 # ifdef IS_IN_rtld
diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index d2283bcd4a..df6ce8b13e 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -168,9 +168,58 @@ gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp,
   return 0;
 }
 
+/* Convert struct hostent to a list of struct gaih_addrtuple objects.
+   h_name is not copied, and the struct hostent object must not be
+   deallocated prematurely.  *RESULT must be NULL or a pointer to an
+   object allocated using malloc, which is freed.  */
+static bool
+convert_hostent_to_gaih_addrtuple (const struct addrinfo *req,
+				   int family,
+				   struct hostent *h,
+				   struct gaih_addrtuple **result)
+{
+  free (*result);
+  *result = NULL;
+
+  /* Count the number of addresses in h->h_addr_list.  */
+  size_t count = 0;
+  for (char **p = h->h_addr_list; *p != NULL; ++p)
+    ++count;
+
+  /* Report no data if no addresses are available, or if the incoming
+     address size is larger than what we can store.  */
+  if (count == 0 || h->h_length > sizeof (((struct gaih_addrtuple) {}).addr))
+    return true;
+
+  struct gaih_addrtuple *array = calloc (count, sizeof (*array));
+  if (array == NULL)
+    return false;
+
+  for (size_t i = 0; i < count; ++i)
+    {
+      if (family == AF_INET && req->ai_family == AF_INET6)
+	{
+	  /* Perform address mapping. */
+	  array[i].family = AF_INET6;
+	  memcpy(array[i].addr + 3, h->h_addr_list[i], sizeof (uint32_t));
+	  array[i].addr[2] = htonl (0xffff);
+	}
+      else
+	{
+	  array[i].family = family;
+	  memcpy (array[i].addr, h->h_addr_list[i], h->h_length);
+	}
+      array[i].next = array + i + 1;
+    }
+  array[0].name = h->h_name;
+  array[count - 1].next = NULL;
+
+  *result = array;
+  return true;
+}
+
 #define gethosts(_family, _type) \
  {									      \
-  int i;								      \
   int herrno;								      \
   struct hostent th;							      \
   struct hostent *h;							      \
@@ -219,36 +268,23 @@ gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp,
     }									      \
   else if (h != NULL)							      \
     {									      \
-      for (i = 0; h->h_addr_list[i]; i++)				      \
+      /* Make sure that addrmem can be freed.  */			      \
+      if (!malloc_addrmem)						      \
+	addrmem = NULL;							      \
+      if (!convert_hostent_to_gaih_addrtuple (req, _family,h, &addrmem))      \
 	{								      \
-	  if (*pat == NULL)						      \
-	    {								      \
-	      *pat = __alloca (sizeof (struct gaih_addrtuple));		      \
-	      (*pat)->scopeid = 0;					      \
-	    }								      \
-	  uint32_t *addr = (*pat)->addr;				      \
-	  (*pat)->next = NULL;						      \
-	  (*pat)->name = i == 0 ? strdupa (h->h_name) : NULL;		      \
-	  if (_family == AF_INET && req->ai_family == AF_INET6)		      \
-	    {								      \
-	      (*pat)->family = AF_INET6;				      \
-	      addr[3] = *(uint32_t *) h->h_addr_list[i];		      \
-	      addr[2] = htonl (0xffff);					      \
-	      addr[1] = 0;						      \
-	      addr[0] = 0;						      \
-	    }								      \
-	  else								      \
-	    {								      \
-	      (*pat)->family = _family;					      \
-	      memcpy (addr, h->h_addr_list[i], sizeof(_type));		      \
-	    }								      \
-	  pat = &((*pat)->next);					      \
+	  _res.options |= old_res_options & RES_USE_INET6;		      \
+	  result = -EAI_SYSTEM;						      \
+	  goto free_and_return;						      \
 	}								      \
+      *pat = addrmem;							      \
+      /* The conversion uses malloc unconditionally.  */		      \
+      malloc_addrmem = true;						      \
 									      \
       if (localcanon !=	NULL && canon == NULL)				      \
 	canon = strdupa (localcanon);					      \
 									      \
-      if (_family == AF_INET6 && i > 0)					      \
+      if (_family == AF_INET6 && *pat != NULL)				      \
 	got_ipv6 = true;						      \
     }									      \
  }
@@ -612,44 +648,16 @@ gaih_inet (const char *name, const struct gaih_service *service,
 		{
 		  if (h != NULL)
 		    {
-		      int i;
-		      /* We found data, count the number of addresses.  */
-		      for (i = 0; h->h_addr_list[i]; ++i)
-			;
-		      if (i > 0 && *pat != NULL)
-			--i;
-
-		      if (__libc_use_alloca (alloca_used
-					     + i * sizeof (struct gaih_addrtuple)))
-			addrmem = alloca_account (i * sizeof (struct gaih_addrtuple),
-						  alloca_used);
-		      else
-			{
-			  addrmem = malloc (i
-					    * sizeof (struct gaih_addrtuple));
-			  if (addrmem == NULL)
-			    {
-			      result = -EAI_MEMORY;
-			      goto free_and_return;
-			    }
-			  malloc_addrmem = true;
-			}
-
-		      /* Now convert it into the list.  */
-		      struct gaih_addrtuple *addrfree = addrmem;
-		      for (i = 0; h->h_addr_list[i]; ++i)
+		      /* We found data, convert it.  */
+		      if (!convert_hostent_to_gaih_addrtuple
+			  (req, AF_INET, h, &addrmem))
 			{
-			  if (*pat == NULL)
-			    {
-			      *pat = addrfree++;
-			      (*pat)->scopeid = 0;
-			    }
-			  (*pat)->next = NULL;
-			  (*pat)->family = AF_INET;
-			  memcpy ((*pat)->addr, h->h_addr_list[i],
-				  h->h_length);
-			  pat = &((*pat)->next);
+			  result = -EAI_MEMORY;
+			  goto free_and_return;
 			}
+		      *pat = addrmem;
+		      /* The conversion uses malloc unconditionally.  */
+		      malloc_addrmem = true;
 		    }
 		}
 	      else
diff --git a/sysdeps/unix/sysv/linux/i386/glob64.c b/sysdeps/unix/sysv/linux/i386/glob64.c
index b4fcd1a73c..802c957d6c 100644
--- a/sysdeps/unix/sysv/linux/i386/glob64.c
+++ b/sysdeps/unix/sysv/linux/i386/glob64.c
@@ -1,3 +1,21 @@
+/* Two glob variants with 64-bit support, for dirent64 and __olddirent64.
+   Copyright (C) 1998-2016 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 <dirent.h>
 #include <glob.h>
 #include <sys/stat.h>
@@ -38,11 +56,15 @@ int __old_glob64 (const char *__pattern, int __flags,
 
 #undef dirent
 #define dirent __old_dirent64
+#undef GL_READDIR
+# define GL_READDIR(pglob, stream) \
+  ((struct __old_dirent64 *) (pglob)->gl_readdir (stream))
 #undef __readdir
 #define __readdir(dirp) __old_readdir64 (dirp)
 #undef glob
 #define glob(pattern, flags, errfunc, pglob) \
   __old_glob64 (pattern, flags, errfunc, pglob)
+#define convert_dirent __old_convert_dirent
 #define glob_in_dir __old_glob_in_dir
 #define GLOB_ATTRIBUTE attribute_compat_text_section
 
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S b/sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S
index 83cf0d8ffa..67ea206de4 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S
@@ -17,6 +17,14 @@
 
 #include <sysdep.h>
 
+/* We do not want .eh_frame info so that __makecontext_ret stops unwinding
+   if backtrace was called within a context created by makecontext. (There
+   is also no .eh_frame info for _start or thread_start.)  */
+#undef cfi_startproc
+#define cfi_startproc
+#undef cfi_endproc
+#define cfi_endproc
+
 ENTRY(__makecontext_ret)
 	basr  %r14,%r7
 	ltr   %r8,%r8			/* Check whether uc_link is 0.  */
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/setcontext.S b/sysdeps/unix/sysv/linux/s390/s390-32/setcontext.S
index 42839e26f1..b26377398a 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/setcontext.S
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/setcontext.S
@@ -34,7 +34,7 @@ ENTRY(__setcontext)
 	lr	%r1,%r2
 
 	/* rt_sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL, sigsetsize).  */
-	la      %r2,SIG_BLOCK
+	la      %r2,SIG_SETMASK
 	la	%r3,SC_MASK(%r1)
 	slr	%r4,%r4
 	lhi	%r5,_NSIG8
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/swapcontext.S b/sysdeps/unix/sysv/linux/s390/s390-32/swapcontext.S
index 9206aa334d..8f9cfd834d 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/swapcontext.S
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/swapcontext.S
@@ -24,7 +24,7 @@
 /*  __swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
 
   Saves the machine context in oucp such that when it is activated,
-  it appears as if __swapcontextt() returned again, restores the
+  it appears as if __swapcontext() returned again, restores the
   machine context in ucp and thereby resumes execution in that
   context.
 
@@ -39,13 +39,6 @@ ENTRY(__swapcontext)
 	lr	%r1,%r2
 	lr      %r0,%r3
 
-	/* sigprocmask (SIG_BLOCK, NULL, &sc->sc_mask).  */
-	la      %r2,SIG_BLOCK
-	slr	%r3,%r3
-	la	%r4,SC_MASK(%r1)
-	lhi	%r5,_NSIG8
-	svc	SYS_ify(rt_sigprocmask)
-
 	/* Store fpu context.  */
 	stfpc   SC_FPC(%r1)
 	std     %f0,SC_FPRS(%r1)
@@ -74,11 +67,12 @@ ENTRY(__swapcontext)
 	/* Store general purpose registers.  */
 	stm     %r0,%r15,SC_GPRS(%r1)
 
-	/* sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL).  */
-	la      %r2,SIG_BLOCK
+	/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, &oucp->uc_sigmask,
+	   sigsetsize).  */
+	la      %r2,SIG_SETMASK
 	lr	%r5,%r0
 	la	%r3,SC_MASK(%r5)
-	slr	%r4,%r4
+	la	%r4,SC_MASK(%r1)
 	lhi	%r5,_NSIG8
 	svc	SYS_ify(rt_sigprocmask)
 
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/__makecontext_ret.S b/sysdeps/unix/sysv/linux/s390/s390-64/__makecontext_ret.S
index 71ecbab08e..a2bf3ca02d 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/__makecontext_ret.S
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/__makecontext_ret.S
@@ -17,6 +17,14 @@
 
 #include <sysdep.h>
 
+/* We do not want .eh_frame info so that __makecontext_ret stops unwinding
+   if backtrace was called within a context created by makecontext. (There
+   is also no .eh_frame info for _start or thread_start.)  */
+#undef cfi_startproc
+#define cfi_startproc
+#undef cfi_endproc
+#define cfi_endproc
+
 ENTRY(__makecontext_ret)
 	basr	%r14,%r7
 	ltgr	%r8,%r8			/* Check whether uc_link is 0.  */
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/setcontext.S b/sysdeps/unix/sysv/linux/s390/s390-64/setcontext.S
index 83df5ce461..1464e6a094 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/setcontext.S
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/setcontext.S
@@ -34,7 +34,7 @@ ENTRY(__setcontext)
 	lgr	%r1,%r2
 
 	/* sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL).  */
-	la      %r2,SIG_BLOCK
+	la      %r2,SIG_SETMASK
 	la	%r3,SC_MASK(%r1)
 	slgr	%r4,%r4
 	lghi	%r5,_NSIG8
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S b/sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S
index e3e624c91b..8346fd5dd1 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S
@@ -24,7 +24,7 @@
 /*  __swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
 
   Saves the machine context in oucp such that when it is activated,
-  it appears as if __swapcontextt() returned again, restores the
+  it appears as if __swapcontext() returned again, restores the
   machine context in ucp and thereby resumes execution in that
   context.
 
@@ -39,13 +39,6 @@ ENTRY(__swapcontext)
 	lgr	%r1,%r2
 	lgr     %r0,%r3
 
-	/* sigprocmask (SIG_BLOCK, NULL, &sc->sc_mask).  */
-	la      %r2,SIG_BLOCK
-	slgr	%r3,%r3
-	la	%r4,SC_MASK(%r1)
-	lghi	%r5,_NSIG8
-	svc	SYS_ify(rt_sigprocmask)
-
 	/* Store fpu context.  */
 	stfpc   SC_FPC(%r1)
 	std     %f0,SC_FPRS(%r1)
@@ -74,12 +67,13 @@ ENTRY(__swapcontext)
 	/* Store general purpose registers.  */
 	stmg    %r0,%r15,SC_GPRS(%r1)
 
-	/* rt_sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL, sigsetsize).  */
-	la      %r2,SIG_BLOCK
+	/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, &oucp->uc_sigmask,
+	   sigsetsize).  */
+	la      %r2,SIG_SETMASK
 	lgr	%r5,%r0
 	la	%r3,SC_MASK(%r5)
+	la	%r4,SC_MASK(%r1)
 	lghi	%r5,_NSIG8
-	slgr	%r4,%r4
 	svc	SYS_ify(rt_sigprocmask)
 
 	/* Load fpu context.  */
diff --git a/time/strftime_l.c b/time/strftime_l.c
index dfb7b4c483..29c7cdd556 100644
--- a/time/strftime_l.c
+++ b/time/strftime_l.c
@@ -509,13 +509,17 @@ __strftime_internal (s, maxsize, format, tp, tzset_called ut_argument
      only a few elements.  Dereference the pointers only if the format
      requires this.  Then it is ok to fail if the pointers are invalid.  */
 # define a_wkday \
-  ((const CHAR_T *) _NL_CURRENT (LC_TIME, NLW(ABDAY_1) + tp->tm_wday))
+  ((const CHAR_T *) (tp->tm_wday < 0 || tp->tm_wday > 6			     \
+		     ? "?" : _NL_CURRENT (LC_TIME, NLW(ABDAY_1) + tp->tm_wday)))
 # define f_wkday \
-  ((const CHAR_T *) _NL_CURRENT (LC_TIME, NLW(DAY_1) + tp->tm_wday))
+  ((const CHAR_T *) (tp->tm_wday < 0 || tp->tm_wday > 6			     \
+		     ? "?" : _NL_CURRENT (LC_TIME, NLW(DAY_1) + tp->tm_wday)))
 # define a_month \
-  ((const CHAR_T *) _NL_CURRENT (LC_TIME, NLW(ABMON_1) + tp->tm_mon))
+  ((const CHAR_T *) (tp->tm_mon < 0 || tp->tm_mon > 11			     \
+		     ? "?" : _NL_CURRENT (LC_TIME, NLW(ABMON_1) + tp->tm_mon)))
 # define f_month \
-  ((const CHAR_T *) _NL_CURRENT (LC_TIME, NLW(MON_1) + tp->tm_mon))
+  ((const CHAR_T *) (tp->tm_mon < 0 || tp->tm_mon > 11			     \
+		     ? "?" : _NL_CURRENT (LC_TIME, NLW(MON_1) + tp->tm_mon)))
 # define ampm \
   ((const CHAR_T *) _NL_CURRENT (LC_TIME, tp->tm_hour > 11		      \
 				 ? NLW(PM_STR) : NLW(AM_STR)))
@@ -525,8 +529,10 @@ __strftime_internal (s, maxsize, format, tp, tzset_called ut_argument
 # define ap_len STRLEN (ampm)
 #else
 # if !HAVE_STRFTIME
-#  define f_wkday (weekday_name[tp->tm_wday])
-#  define f_month (month_name[tp->tm_mon])
+#  define f_wkday (tp->tm_wday < 0 || tp->tm_wday > 6	\
+		   ? "?" : weekday_name[tp->tm_wday])
+#  define f_month (tp->tm_mon < 0 || tp->tm_mon > 11	\
+		   ? "?" : month_name[tp->tm_mon])
 #  define a_wkday f_wkday
 #  define a_month f_month
 #  define ampm (L_("AMPM") + 2 * (tp->tm_hour > 11))
@@ -1320,7 +1326,7 @@ __strftime_internal (s, maxsize, format, tp, tzset_called ut_argument
 		  *tzset_called = true;
 		}
 # endif
-	      zone = tzname[tp->tm_isdst];
+	      zone = tp->tm_isdst <= 1 ? tzname[tp->tm_isdst] : "?";
 	    }
 #endif
 	  if (! zone)
diff --git a/time/tst-strftime.c b/time/tst-strftime.c
index 374fba4262..af3ff72faf 100644
--- a/time/tst-strftime.c
+++ b/time/tst-strftime.c
@@ -4,6 +4,56 @@
 #include <time.h>
 
 
+static int
+do_bz18985 (void)
+{
+  char buf[1000];
+  struct tm ttm;
+  int rc, ret = 0;
+
+  memset (&ttm, 1, sizeof (ttm));
+  ttm.tm_zone = NULL;  /* Dereferenced directly if non-NULL.  */
+  rc = strftime (buf, sizeof (buf), "%a %A %b %B %c %z %Z", &ttm);
+
+  if (rc == 66)
+    {
+      const char expected[]
+	= "? ? ? ? ? ? 16843009 16843009:16843009:16843009 16844909 +467836 ?";
+      if (0 != strcmp (buf, expected))
+	{
+	  printf ("expected:\n  %s\ngot:\n  %s\n", expected, buf);
+	  ret += 1;
+	}
+    }
+  else
+    {
+      printf ("expected 66, got %d\n", rc);
+      ret += 1;
+    }
+
+  /* Check negative values as well.  */
+  memset (&ttm, 0xFF, sizeof (ttm));
+  ttm.tm_zone = NULL;  /* Dereferenced directly if non-NULL.  */
+  rc = strftime (buf, sizeof (buf), "%a %A %b %B %c %z %Z", &ttm);
+
+  if (rc == 30)
+    {
+      const char expected[] = "? ? ? ? ? ? -1 -1:-1:-1 1899  ";
+      if (0 != strcmp (buf, expected))
+	{
+	  printf ("expected:\n  %s\ngot:\n  %s\n", expected, buf);
+	  ret += 1;
+	}
+    }
+  else
+    {
+      printf ("expected 30, got %d\n", rc);
+      ret += 1;
+    }
+
+  return ret;
+}
+
 static struct
 {
   const char *fmt;
@@ -104,7 +154,7 @@ do_test (void)
 	}
     }
 
-  return result;
+  return result + do_bz18985 ();
 }
 
 #define TEST_FUNCTION do_test ()