Merge from gnulib

This incorporates:
2015-04-24 file-has-acl: new module, split from acl
2015-04-24 manywarnings: add GCC 5.1 warnings
2015-04-21 lstat: fix cross-compilation 'ln -s' problem
2015-04-15 qacl: Simplify HP-UX acl_nontrivial check
2015-04-15 acl: On Linux, check for acls without libacl
2015-04-14 tempname: avoid unused parameter warnings (trivial)
* lib/acl-internal.c: New file, from gnulib.
* lib/file-has-acl.c: Remove; no longer imported from gnulib.
* lib/acl-internal.h, lib/gnulib.mk, lib/qcopy-acl.c, lib/tempname.c:
* m4/acl.m4, m4/gnulib-comp.m4, m4/lstat.m4, m4/manywarnings.m4:
Update from gnulib.

9 files changed, 95 insertions, 512 deletions

diff --git a/lib/file-has-acl.c b/lib/acl-internal.c
index 2ef4e8bdefd..d9bd4461ea6 100644
--- a/lib/file-has-acl.c
+++ b/lib/acl-internal.c
@@ -17,19 +17,12 @@
 
    Written by Paul Eggert, Andreas Grünbacher, and Bruno Haible.  */
 
-/* Without this pragma, gcc 4.7.0 20120126 may suggest that the
-   file_has_acl function might be candidate for attribute 'const'  */
-#if (__GNUC__ == 4 && 6 <= __GNUC_MINOR__) || 4 < __GNUC__
-# pragma GCC diagnostic ignored "-Wsuggest-attribute=const"
-#endif
-
 #include <config.h>
 
 #include "acl.h"
 
 #include "acl-internal.h"
 
-
 #if USE_ACL && HAVE_ACL_GET_FILE
 
 # if HAVE_ACL_TYPE_EXTENDED /* Mac OS X */
@@ -124,7 +117,6 @@ acl_access_nontrivial (acl_t acl)
 
 # endif
 
-
 #elif USE_ACL && HAVE_FACL && defined GETACL /* Solaris, Cygwin, not HP-UX */
 
 /* Test an ACL retrieved with GETACL.
@@ -344,18 +336,19 @@ acl_ace_nontrivial (int count, ace_t *entries)
 /* Return 1 if the given ACL is non-trivial.
    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
 int
-acl_nontrivial (int count, struct acl_entry *entries, struct stat *sb)
+acl_nontrivial (int count, struct acl_entry *entries)
 {
   int i;
 
+  if (count > 3)
+    return 1;
+
   for (i = 0; i < count; i++)
     {
       struct acl_entry *ace = &entries[i];
 
-      if (!((ace->uid == sb->st_uid && ace->gid == ACL_NSGROUP)
-            || (ace->uid == ACL_NSUSER && ace->gid == sb->st_gid)
-            || (ace->uid == ACL_NSUSER && ace->gid == ACL_NSGROUP)))
-        return 1;
+      if (ace->uid != ACL_NSUSER && ace->gid != ACL_NSGROUP)
+        return 1;
     }
   return 0;
 }
@@ -474,446 +467,3 @@ acl_nontrivial (int count, struct acl *entries)
 }
 
 #endif
-
-
-/* Return 1 if NAME has a nontrivial access control list, 0 if NAME
-   only has no or a base access control list, and -1 (setting errno)
-   on error.  SB must be set to the stat buffer of NAME, obtained
-   through stat() or lstat().  */
-
-int
-file_has_acl (char const *name, struct stat const *sb)
-{
-#if USE_ACL
-  if (! S_ISLNK (sb->st_mode))
-    {
-# if HAVE_ACL_GET_FILE
-
-      /* POSIX 1003.1e (draft 17 -- abandoned) specific version.  */
-      /* Linux, FreeBSD, Mac OS X, IRIX, Tru64 */
-      int ret;
-
-      if (HAVE_ACL_EXTENDED_FILE) /* Linux */
-        {
-          /* On Linux, acl_extended_file is an optimized function: It only
-             makes two calls to getxattr(), one for ACL_TYPE_ACCESS, one for
-             ACL_TYPE_DEFAULT.  */
-          ret = acl_extended_file (name);
-        }
-      else /* FreeBSD, Mac OS X, IRIX, Tru64 */
-        {
-#  if HAVE_ACL_TYPE_EXTENDED /* Mac OS X */
-          /* On Mac OS X, acl_get_file (name, ACL_TYPE_ACCESS)
-             and acl_get_file (name, ACL_TYPE_DEFAULT)
-             always return NULL / EINVAL.  There is no point in making
-             these two useless calls.  The real ACL is retrieved through
-             acl_get_file (name, ACL_TYPE_EXTENDED).  */
-          acl_t acl = acl_get_file (name, ACL_TYPE_EXTENDED);
-          if (acl)
-            {
-              ret = acl_extended_nontrivial (acl);
-              acl_free (acl);
-            }
-          else
-            ret = -1;
-#  else /* FreeBSD, IRIX, Tru64 */
-          acl_t acl = acl_get_file (name, ACL_TYPE_ACCESS);
-          if (acl)
-            {
-              int saved_errno;
-
-              ret = acl_access_nontrivial (acl);
-              saved_errno = errno;
-              acl_free (acl);
-              errno = saved_errno;
-#   if HAVE_ACL_FREE_TEXT /* Tru64 */
-              /* On OSF/1, acl_get_file (name, ACL_TYPE_DEFAULT) always
-                 returns NULL with errno not set.  There is no point in
-                 making this call.  */
-#   else /* FreeBSD, IRIX */
-              /* On Linux, FreeBSD, IRIX, acl_get_file (name, ACL_TYPE_ACCESS)
-                 and acl_get_file (name, ACL_TYPE_DEFAULT) on a directory
-                 either both succeed or both fail; it depends on the
-                 file system.  Therefore there is no point in making the second
-                 call if the first one already failed.  */
-              if (ret == 0 && S_ISDIR (sb->st_mode))
-                {
-                  acl = acl_get_file (name, ACL_TYPE_DEFAULT);
-                  if (acl)
-                    {
-                      ret = (0 < acl_entries (acl));
-                      acl_free (acl);
-                    }
-                  else
-                    ret = -1;
-                }
-#   endif
-            }
-          else
-            ret = -1;
-#  endif
-        }
-      if (ret < 0)
-        return - acl_errno_valid (errno);
-      return ret;
-
-# elif HAVE_FACL && defined GETACL /* Solaris, Cygwin, not HP-UX */
-
-#  if defined ACL_NO_TRIVIAL
-
-      /* Solaris 10 (newer version), which has additional API declared in
-         <sys/acl.h> (acl_t) and implemented in libsec (acl_set, acl_trivial,
-         acl_fromtext, ...).  */
-      return acl_trivial (name);
-
-#  else /* Solaris, Cygwin, general case */
-
-      /* Solaris 2.5 through Solaris 10, Cygwin, and contemporaneous versions
-         of Unixware.  The acl() call returns the access and default ACL both
-         at once.  */
-      {
-        /* Initially, try to read the entries into a stack-allocated buffer.
-           Use malloc if it does not fit.  */
-        enum
-          {
-            alloc_init = 4000 / sizeof (aclent_t), /* >= 3 */
-            alloc_max = MIN (INT_MAX, SIZE_MAX / sizeof (aclent_t))
-          };
-        aclent_t buf[alloc_init];
-        size_t alloc = alloc_init;
-        aclent_t *entries = buf;
-        aclent_t *malloced = NULL;
-        int count;
-
-        for (;;)
-          {
-            count = acl (name, GETACL, alloc, entries);
-            if (count < 0 && errno == ENOSPC)
-              {
-                /* Increase the size of the buffer.  */
-                free (malloced);
-                if (alloc > alloc_max / 2)
-                  {
-                    errno = ENOMEM;
-                    return -1;
-                  }
-                alloc = 2 * alloc; /* <= alloc_max */
-                entries = malloced =
-                  (aclent_t *) malloc (alloc * sizeof (aclent_t));
-                if (entries == NULL)
-                  {
-                    errno = ENOMEM;
-                    return -1;
-                  }
-                continue;
-              }
-            break;
-          }
-        if (count < 0)
-          {
-            if (errno == ENOSYS || errno == ENOTSUP)
-              ;
-            else
-              {
-                int saved_errno = errno;
-                free (malloced);
-                errno = saved_errno;
-                return -1;
-              }
-          }
-        else if (count == 0)
-          ;
-        else
-          {
-            /* Don't use MIN_ACL_ENTRIES:  It's set to 4 on Cygwin, but Cygwin
-               returns only 3 entries for files with no ACL.  But this is safe:
-               If there are more than 4 entries, there cannot be only the
-               "user::", "group::", "other:", and "mask:" entries.  */
-            if (count > 4)
-              {
-                free (malloced);
-                return 1;
-              }
-
-            if (acl_nontrivial (count, entries))
-              {
-                free (malloced);
-                return 1;
-              }
-          }
-        free (malloced);
-      }
-
-#   ifdef ACE_GETACL
-      /* Solaris also has a different variant of ACLs, used in ZFS and NFSv4
-         file systems (whereas the other ones are used in UFS file systems).  */
-      {
-        /* Initially, try to read the entries into a stack-allocated buffer.
-           Use malloc if it does not fit.  */
-        enum
-          {
-            alloc_init = 4000 / sizeof (ace_t), /* >= 3 */
-            alloc_max = MIN (INT_MAX, SIZE_MAX / sizeof (ace_t))
-          };
-        ace_t buf[alloc_init];
-        size_t alloc = alloc_init;
-        ace_t *entries = buf;
-        ace_t *malloced = NULL;
-        int count;
-
-        for (;;)
-          {
-            count = acl (name, ACE_GETACL, alloc, entries);
-            if (count < 0 && errno == ENOSPC)
-              {
-                /* Increase the size of the buffer.  */
-                free (malloced);
-                if (alloc > alloc_max / 2)
-                  {
-                    errno = ENOMEM;
-                    return -1;
-                  }
-                alloc = 2 * alloc; /* <= alloc_max */
-                entries = malloced = (ace_t *) malloc (alloc * sizeof (ace_t));
-                if (entries == NULL)
-                  {
-                    errno = ENOMEM;
-                    return -1;
-                  }
-                continue;
-              }
-            break;
-          }
-        if (count < 0)
-          {
-            if (errno == ENOSYS || errno == EINVAL)
-              ;
-            else
-              {
-                int saved_errno = errno;
-                free (malloced);
-                errno = saved_errno;
-                return -1;
-              }
-          }
-        else if (count == 0)
-          ;
-        else
-          {
-            /* In the old (original Solaris 10) convention:
-               If there are more than 3 entries, there cannot be only the
-               ACE_OWNER, ACE_GROUP, ACE_OTHER entries.
-               In the newer Solaris 10 and Solaris 11 convention:
-               If there are more than 6 entries, there cannot be only the
-               ACE_OWNER, ACE_GROUP, ACE_EVERYONE entries, each once with
-               NEW_ACE_ACCESS_ALLOWED_ACE_TYPE and once with
-               NEW_ACE_ACCESS_DENIED_ACE_TYPE.  */
-            if (count > 6)
-              {
-                free (malloced);
-                return 1;
-              }
-
-            if (acl_ace_nontrivial (count, entries))
-              {
-                free (malloced);
-                return 1;
-              }
-          }
-        free (malloced);
-      }
-#   endif
-
-      return 0;
-#  endif
-
-# elif HAVE_GETACL /* HP-UX */
-
-      {
-        struct acl_entry entries[NACLENTRIES];
-        int count;
-
-        count = getacl (name, NACLENTRIES, entries);
-
-        if (count < 0)
-          {
-            /* ENOSYS is seen on newer HP-UX versions.
-               EOPNOTSUPP is typically seen on NFS mounts.
-               ENOTSUP was seen on Quantum StorNext file systems (cvfs).  */
-            if (errno == ENOSYS || errno == EOPNOTSUPP || errno == ENOTSUP)
-              ;
-            else
-              return -1;
-          }
-        else if (count == 0)
-          return 0;
-        else /* count > 0 */
-          {
-            if (count > NACLENTRIES)
-              /* If NACLENTRIES cannot be trusted, use dynamic memory
-                 allocation.  */
-              abort ();
-
-            /* If there are more than 3 entries, there cannot be only the
-               (uid,%), (%,gid), (%,%) entries.  */
-            if (count > 3)
-              return 1;
-
-            {
-              struct stat statbuf;
-
-              if (stat (name, &statbuf) < 0)
-                return -1;
-
-              return acl_nontrivial (count, entries, &statbuf);
-            }
-          }
-      }
-
-#  if HAVE_ACLV_H /* HP-UX >= 11.11 */
-
-      {
-        struct acl entries[NACLVENTRIES];
-        int count;
-
-        count = acl ((char *) name, ACL_GET, NACLVENTRIES, entries);
-
-        if (count < 0)
-          {
-            /* EOPNOTSUPP is seen on NFS in HP-UX 11.11, 11.23.
-               EINVAL is seen on NFS in HP-UX 11.31.  */
-            if (errno == ENOSYS || errno == EOPNOTSUPP || errno == EINVAL)
-              ;
-            else
-              return -1;
-          }
-        else if (count == 0)
-          return 0;
-        else /* count > 0 */
-          {
-            if (count > NACLVENTRIES)
-              /* If NACLVENTRIES cannot be trusted, use dynamic memory
-                 allocation.  */
-              abort ();
-
-            /* If there are more than 4 entries, there cannot be only the
-               four base ACL entries.  */
-            if (count > 4)
-              return 1;
-
-            return aclv_nontrivial (count, entries);
-          }
-      }
-
-#  endif
-
-# elif HAVE_ACLX_GET && defined ACL_AIX_WIP /* AIX */
-
-      acl_type_t type;
-      char aclbuf[1024];
-      void *acl = aclbuf;
-      size_t aclsize = sizeof (aclbuf);
-      mode_t mode;
-
-      for (;;)
-        {
-          /* The docs say that type being 0 is equivalent to ACL_ANY, but it
-             is not true, in AIX 5.3.  */
-          type.u64 = ACL_ANY;
-          if (aclx_get (name, 0, &type, aclbuf, &aclsize, &mode) >= 0)
-            break;
-          if (errno == ENOSYS)
-            return 0;
-          if (errno != ENOSPC)
-            {
-              if (acl != aclbuf)
-                {
-                  int saved_errno = errno;
-                  free (acl);
-                  errno = saved_errno;
-                }
-              return -1;
-            }
-          aclsize = 2 * aclsize;
-          if (acl != aclbuf)
-            free (acl);
-          acl = malloc (aclsize);
-          if (acl == NULL)
-            {
-              errno = ENOMEM;
-              return -1;
-            }
-        }
-
-      if (type.u64 == ACL_AIXC)
-        {
-          int result = acl_nontrivial ((struct acl *) acl);
-          if (acl != aclbuf)
-            free (acl);
-          return result;
-        }
-      else if (type.u64 == ACL_NFS4)
-        {
-          int result = acl_nfs4_nontrivial ((nfs4_acl_int_t *) acl);
-          if (acl != aclbuf)
-            free (acl);
-          return result;
-        }
-      else
-        {
-          /* A newer type of ACL has been introduced in the system.
-             We should better support it.  */
-          if (acl != aclbuf)
-            free (acl);
-          errno = EINVAL;
-          return -1;
-        }
-
-# elif HAVE_STATACL /* older AIX */
-
-      union { struct acl a; char room[4096]; } u;
-
-      if (statacl (name, STX_NORMAL, &u.a, sizeof (u)) < 0)
-        return -1;
-
-      return acl_nontrivial (&u.a);
-
-# elif HAVE_ACLSORT /* NonStop Kernel */
-
-      {
-        struct acl entries[NACLENTRIES];
-        int count;
-
-        count = acl ((char *) name, ACL_GET, NACLENTRIES, entries);
-
-        if (count < 0)
-          {
-            if (errno == ENOSYS || errno == ENOTSUP)
-              ;
-            else
-              return -1;
-          }
-        else if (count == 0)
-          return 0;
-        else /* count > 0 */
-          {
-            if (count > NACLENTRIES)
-              /* If NACLENTRIES cannot be trusted, use dynamic memory
-                 allocation.  */
-              abort ();
-
-            /* If there are more than 4 entries, there cannot be only the
-               four base ACL entries.  */
-            if (count > 4)
-              return 1;
-
-            return acl_nontrivial (count, entries);
-          }
-      }
-
-# endif
-    }
-#endif
-
-  return 0;
-}
diff --git a/lib/acl-internal.h b/lib/acl-internal.h
index 243ca32b822..9b9fae2e9e0 100644
--- a/lib/acl-internal.h
+++ b/lib/acl-internal.h
@@ -220,7 +220,7 @@ extern int acl_ace_nontrivial (int count, ace_t *entries) _GL_ATTRIBUTE_PURE;
 
 /* Return 1 if the given ACL is non-trivial.
    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
-extern int acl_nontrivial (int count, struct acl_entry *entries, struct stat *sb);
+extern int acl_nontrivial (int count, struct acl_entry *entries);
 
 #  if HAVE_ACLV_H /* HP-UX >= 11.11 */
 
diff --git a/lib/gnulib.mk b/lib/gnulib.mk
index 273b018bdb8..bec0d3bb19b 100644
--- a/lib/gnulib.mk
+++ b/lib/gnulib.mk
@@ -698,7 +698,7 @@ EXTRA_libgnu_a_SOURCES += putenv.c
 
 ## begin gnulib module qacl
 
-libgnu_a_SOURCES += acl-errno-valid.c file-has-acl.c qcopy-acl.c qset-acl.c
+libgnu_a_SOURCES += acl-errno-valid.c acl-internal.c qcopy-acl.c qset-acl.c
 
 EXTRA_DIST += acl-internal.h acl.h acl_entries.c
 
diff --git a/lib/qcopy-acl.c b/lib/qcopy-acl.c
index aac76a12432..bc258ba560b 100644
--- a/lib/qcopy-acl.c
+++ b/lib/qcopy-acl.c
@@ -437,20 +437,9 @@ qcopy_acl (const char *src_name, int source_desc, const char *dst_name,
       if (ret < 0 && saved_errno == 0)
         {
           saved_errno = errno;
-          if (errno == ENOSYS || errno == EOPNOTSUPP || errno == ENOTSUP)
-            {
-              struct stat source_statbuf;
-
-              if ((source_desc != -1
-                   ? fstat (source_desc, &source_statbuf)
-                   : stat (src_name, &source_statbuf)) == 0)
-                {
-                  if (!acl_nontrivial (count, entries, &source_statbuf))
-                    saved_errno = 0;
-                }
-              else
-                saved_errno = errno;
-            }
+          if (errno == ENOSYS || errno == EOPNOTSUPP || errno == ENOTSUP
+              && !acl_nontrivial (count, entries))
+                saved_errno = 0;
         }
       else
         did_chmod = 1;
diff --git a/lib/tempname.c b/lib/tempname.c
index 8e6d26cc485..69c572fbcb4 100644
--- a/lib/tempname.c
+++ b/lib/tempname.c
@@ -269,13 +269,13 @@ try_file (char *tmpl, void *flags)
 }
 
 static int
-try_dir (char *tmpl, void *flags)
+try_dir (char *tmpl, void *flags _GL_UNUSED)
 {
   return __mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR);
 }
 
 static int
-try_nocreate (char *tmpl, void *flags)
+try_nocreate (char *tmpl, void *flags _GL_UNUSED)
 {
   struct_stat64 st;
 
diff --git a/m4/acl.m4 b/m4/acl.m4
index c77f0edd0e7..186353c395b 100644
--- a/m4/acl.m4
+++ b/m4/acl.m4
@@ -1,5 +1,5 @@
 # acl.m4 - check for access control list (ACL) primitives
-# serial 17
+# serial 18
 
 # Copyright (C) 2002, 2004-2015 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -8,23 +8,29 @@
 
 # Written by Paul Eggert and Jim Meyering.
 
-AC_DEFUN([gl_FUNC_ACL],
+AC_DEFUN([gl_FUNC_ACL_ARG],
 [
+  gl_need_lib_has_acl=
   AC_ARG_ENABLE([acl],
     AS_HELP_STRING([--disable-acl], [do not support ACLs]),
     , [enable_acl=auto])
+])
+
 
+AC_DEFUN([gl_FUNC_ACL],
+[
+  AC_REQUIRE([gl_FUNC_ACL_ARG])
   AC_CHECK_FUNCS_ONCE([fchmod])
   LIB_ACL=
   use_acl=0
-  if test "x$enable_acl" != "xno"; then
+  if test "$enable_acl" != no; then
     dnl On all platforms, the ACL related API is declared in <sys/acl.h>.
     AC_CHECK_HEADERS([sys/acl.h])
     if test $ac_cv_header_sys_acl_h = yes; then
       ac_save_LIBS=$LIBS
 
-      dnl Test for POSIX-draft-like API (Linux, FreeBSD, Mac OS X, IRIX, Tru64).
-      dnl -lacl is needed on Linux, -lpacl is needed on OSF/1.
+      dnl Test for POSIX-draft-like API (GNU/Linux, FreeBSD, Mac OS X,
+      dnl IRIX, Tru64).  -lacl is needed on GNU/Linux, -lpacl on OSF/1.
       if test $use_acl = 0; then
         AC_SEARCH_LIBS([acl_get_file], [acl pacl],
           [if test "$ac_cv_search_acl_get_file" != "none required"; then
@@ -40,7 +46,7 @@ AC_DEFUN([gl_FUNC_ACL],
            # If the acl_get_file bug is detected, don't enable the ACL support.
            gl_ACL_GET_FILE([use_acl=1], [])
            if test $use_acl = 1; then
-             dnl On Linux, additional API is declared in <acl/libacl.h>.
+             dnl On GNU/Linux, an additional API is declared in <acl/libacl.h>.
              AC_CHECK_HEADERS([acl/libacl.h])
              AC_REPLACE_FUNCS([acl_entries])
              AC_CACHE_CHECK([for ACL_FIRST_ENTRY],
@@ -124,13 +130,15 @@ int type = ACL_TYPE_EXTENDED;]])],
 
       LIBS=$ac_save_LIBS
     fi
-    if test "x$enable_acl$use_acl" = "xyes0"; then
+
+    if test "$enable_acl$use_acl" = yes0; then
       AC_MSG_ERROR([ACLs enabled but support not detected])
-    elif test "x$enable_acl$use_acl" = "xauto0"; then
+    elif test "$enable_acl$use_acl" = auto0; then
       AC_MSG_WARN([libacl development library was not found or not usable.])
       AC_MSG_WARN([AC_PACKAGE_NAME will be built without ACL support.])
     fi
   fi
+  test $gl_need_lib_has_acl && LIB_HAS_ACL=$LIB_ACL
   AC_SUBST([LIB_ACL])
   AC_DEFINE_UNQUOTED([USE_ACL], [$use_acl],
     [Define to nonzero if you want access control list support.])
@@ -139,7 +147,7 @@ int type = ACL_TYPE_EXTENDED;]])],
 ])
 
 # gl_ACL_GET_FILE(IF-WORKS, IF-NOT)
-# -------------------------------------
+# ---------------------------------
 # If 'acl_get_file' works (does not have a particular bug),
 # run IF-WORKS, otherwise, IF-NOT.
 # When building natively, test for a Darwin 8.7.0 bug, whereby acl_get_file
@@ -166,3 +174,24 @@ AC_DEFUN([gl_ACL_GET_FILE],
         fi])])
   AS_IF([test "$gl_cv_func_working_acl_get_file" != no], [$1], [$2])
 ])
+
+# On GNU/Linux, testing if a file has an acl can be done with the getxattr
+# syscall which doesn't require linking against additional libraries.
+AC_DEFUN([gl_FILE_HAS_ACL],
+[
+  AC_REQUIRE([gl_FUNC_ACL_ARG])
+  if test "$enable_acl" != no; then
+    AC_CHECK_HEADERS([linux/xattr.h],
+      [AC_CHECK_HEADERS([sys/xattr.h],
+         [AC_CHECK_FUNCS([getxattr])])])
+  fi
+  if test "$ac_cv_header_sys_xattr_h,$ac_cv_header_linux_xattr_h,$ac_cv_func_getxattr" = yes,yes,yes; then
+    LIB_HAS_ACL=
+  else
+    dnl Set gl_need_lib_has_acl to a nonempty value, so that any
+    dnl later gl_FUNC_ACL call will set LIB_HAS_ACL=$LIB_ACL.
+    gl_need_lib_has_acl=1
+    LIB_HAS_ACL=$LIB_ACL
+  fi
+  AC_SUBST([LIB_HAS_ACL])
+])
diff --git a/m4/gnulib-comp.m4 b/m4/gnulib-comp.m4
index f32a4ddca5c..06636cfe76c 100644
--- a/m4/gnulib-comp.m4
+++ b/m4/gnulib-comp.m4
@@ -818,6 +818,7 @@ AC_DEFUN([gl_FILE_LIST], [
   build-aux/snippet/warn-on-use.h
   build-aux/update-copyright
   lib/acl-errno-valid.c
+  lib/acl-internal.c
   lib/acl-internal.h
   lib/acl.h
   lib/acl_entries.c
@@ -856,7 +857,6 @@ AC_DEFUN([gl_FILE_LIST], [
   lib/fcntl.in.h
   lib/fdatasync.c
   lib/fdopendir.c
-  lib/file-has-acl.c
   lib/filemode.c
   lib/filemode.h
   lib/fpending.c
diff --git a/m4/lstat.m4 b/m4/lstat.m4
index f6c7dd1ce44..adf752c0dfa 100644
--- a/m4/lstat.m4
+++ b/m4/lstat.m4
@@ -1,4 +1,4 @@
-# serial 26
+# serial 27
 
 # Copyright (C) 1997-2001, 2003-2015 Free Software Foundation, Inc.
 #
@@ -37,30 +37,28 @@ AC_DEFUN([gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK],
     [gl_cv_func_lstat_dereferences_slashed_symlink],
     [rm -f conftest.sym conftest.file
      echo >conftest.file
-     if test "$as_ln_s" = "ln -s" && ln -s conftest.file conftest.sym; then
-       AC_RUN_IFELSE(
-         [AC_LANG_PROGRAM(
-            [AC_INCLUDES_DEFAULT],
-            [[struct stat sbuf;
-              /* Linux will dereference the symlink and fail, as required by
-                 POSIX.  That is better in the sense that it means we will not
-                 have to compile and use the lstat wrapper.  */
-              return lstat ("conftest.sym/", &sbuf) == 0;
-            ]])],
-         [gl_cv_func_lstat_dereferences_slashed_symlink=yes],
-         [gl_cv_func_lstat_dereferences_slashed_symlink=no],
-         [case "$host_os" in
-                    # Guess yes on glibc systems.
-            *-gnu*) gl_cv_func_lstat_dereferences_slashed_symlink="guessing yes" ;;
-                    # If we don't know, assume the worst.
-            *)      gl_cv_func_lstat_dereferences_slashed_symlink="guessing no" ;;
-          esac
-         ])
-     else
-       # If the 'ln -s' command failed, then we probably don't even
-       # have an lstat function.
-       gl_cv_func_lstat_dereferences_slashed_symlink="guessing no"
-     fi
+     AC_RUN_IFELSE(
+       [AC_LANG_PROGRAM(
+          [AC_INCLUDES_DEFAULT],
+          [[struct stat sbuf;
+            if (symlink ("conftest.file", "conftest.sym") != 0)
+              return 1;
+            /* Linux will dereference the symlink and fail, as required by
+               POSIX.  That is better in the sense that it means we will not
+               have to compile and use the lstat wrapper.  */
+            return lstat ("conftest.sym/", &sbuf) == 0;
+          ]])],
+       [gl_cv_func_lstat_dereferences_slashed_symlink=yes],
+       [gl_cv_func_lstat_dereferences_slashed_symlink=no],
+       [case "$host_os" in
+          *-gnu*)
+            # Guess yes on glibc systems.
+            gl_cv_func_lstat_dereferences_slashed_symlink="guessing yes" ;;
+          *)
+            # If we don't know, assume the worst.
+            gl_cv_func_lstat_dereferences_slashed_symlink="guessing no" ;;
+        esac
+       ])
      rm -f conftest.sym conftest.file
     ])
   case "$gl_cv_func_lstat_dereferences_slashed_symlink" in
diff --git a/m4/manywarnings.m4 b/m4/manywarnings.m4
index 44da98e38da..b4e38d94463 100644
--- a/m4/manywarnings.m4
+++ b/m4/manywarnings.m4
@@ -108,12 +108,13 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     -Waddress \
     -Waggressive-loop-optimizations \
     -Wall \
-    -Warray-bounds \
     -Wattributes \
     -Wbad-function-cast \
+    -Wbool-compare \
     -Wbuiltin-macro-redefined \
     -Wcast-align \
     -Wchar-subscripts \
+    -Wchkp \
     -Wclobbered \
     -Wcomment \
     -Wcomments \
@@ -122,7 +123,10 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     -Wdate-time \
     -Wdeprecated \
     -Wdeprecated-declarations \
+    -Wdesignated-init \
     -Wdisabled-optimization \
+    -Wdiscarded-array-qualifiers \
+    -Wdiscarded-qualifiers \
     -Wdiv-by-zero \
     -Wdouble-promotion \
     -Wempty-body \
@@ -133,6 +137,7 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     -Wformat-extra-args \
     -Wformat-nonliteral \
     -Wformat-security \
+    -Wformat-signedness \
     -Wformat-y2k \
     -Wformat-zero-length \
     -Wfree-nonheap-object \
@@ -140,15 +145,19 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     -Wimplicit \
     -Wimplicit-function-declaration \
     -Wimplicit-int \
+    -Wincompatible-pointer-types \
     -Winit-self \
     -Winline \
+    -Wint-conversion \
     -Wint-to-pointer-cast \
     -Winvalid-memory-model \
     -Winvalid-pch \
     -Wjump-misses-init \
+    -Wlogical-not-parentheses \
     -Wlogical-op \
     -Wmain \
     -Wmaybe-uninitialized \
+    -Wmemset-transposed-args \
     -Wmissing-braces \
     -Wmissing-declarations \
     -Wmissing-field-initializers \
@@ -159,6 +168,7 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     -Wnarrowing \
     -Wnested-externs \
     -Wnonnull \
+    -Wodr \
     -Wold-style-declaration \
     -Wold-style-definition \
     -Wopenmp-simd \
@@ -176,6 +186,9 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     -Wreturn-type \
     -Wsequence-point \
     -Wshadow \
+    -Wshift-count-negative \
+    -Wshift-count-overflow \
+    -Wsizeof-array-argument \
     -Wsizeof-pointer-memaccess \
     -Wstack-protector \
     -Wstrict-aliasing \
@@ -185,7 +198,10 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     -Wsuggest-attribute=format \
     -Wsuggest-attribute=noreturn \
     -Wsuggest-attribute=pure \
+    -Wsuggest-final-methods \
+    -Wsuggest-final-types \
     -Wswitch \
+    -Wswitch-bool \
     -Wswitch-default \
     -Wsync-nand \
     -Wsystem-headers \
@@ -217,8 +233,9 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     gl_manywarn_set="$gl_manywarn_set $gl_manywarn_item"
   done
 
-  # gcc --help=warnings outputs an unusual form for this option; list
-  # it here so that the above 'comm' command doesn't report a false match.
+  # gcc --help=warnings outputs an unusual form for these options; list
+  # them here so that the above 'comm' command doesn't report a false match.
+  gl_manywarn_set="$gl_manywarn_set -Warray-bounds=2"
   gl_manywarn_set="$gl_manywarn_set -Wnormalized=nfc"
 
   # These are needed for older GCC versions.