Index: binutils/gdb/arch-utils.c
===================================================================
--- binutils.orig/gdb/arch-utils.c	2016-10-14 02:40:40.587665608 +0100
+++ binutils/gdb/arch-utils.c	2016-10-14 03:48:32.492283480 +0100
@@ -787,6 +787,8 @@ gdbarch_info_fill (struct gdbarch_info *
   if (info->byte_order == BFD_ENDIAN_UNKNOWN)
     info->byte_order = default_byte_order;
   info->byte_order_for_code = info->byte_order;
+  /* Wire the default to the last selected byte order.  */
+  default_byte_order = info->byte_order;
 
   /* "(gdb) set osabi ...".  Handled by gdbarch_lookup_osabi.  */
   /* From the manual override, or from file.  */
Index: binutils/gdb/testsuite/gdb.base/endian.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ binutils/gdb/testsuite/gdb.base/endian.c	2016-10-14 03:48:32.521146892 +0100
@@ -0,0 +1,22 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 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 3 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, see <http://www.gnu.org/licenses/>.  */
+
+int
+main (void)
+{
+  return 0;
+}
Index: binutils/gdb/testsuite/gdb.base/endian.exp
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ binutils/gdb/testsuite/gdb.base/endian.exp	2016-10-14 05:10:27.523711889 +0100
@@ -0,0 +1,96 @@
+# 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 3 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, see <http://www.gnu.org/licenses/>.
+
+# Contributed by Imagination Technologies, written by Maciej W. Rozycki.
+
+# Test automatic endianness selection.
+
+standard_testfile
+
+set en_auto "The target endianness is set automatically"
+set en_set "The target is assumed to be"
+
+clean_restart
+
+# First check that the automatic endianness is updated
+# with the `set endian' command.
+gdb_test "set endian auto" \
+    "$en_auto \\\(currently \(\?:big\|little\) endian\\\)" \
+    "default target endianness"
+gdb_test "set endian big" "$en_set big endian" \
+    "set target endianness"
+gdb_test "set endian auto" "$en_auto \\\(currently big endian\\\)" \
+    "auto target endianness"
+gdb_test "set endian little" "$en_set little endian" \
+    "set target endianness little"
+gdb_test "set endian auto" "$en_auto \\\(currently little endian\\\)" \
+    "auto target endianness little"
+gdb_test "set endian big" "$en_set big endian" \
+    "set target endianness big"
+gdb_test "set endian auto" "$en_auto \\\(currently big endian\\\)" \
+    "auto target endianness big"
+
+if { [build_executable ${testfile}.exp $testfile] } {
+    gdb_suppress_entire_file "$pf_prefix cannot build executable"
+}
+
+if { [gdb_file_cmd $binfile] } {
+    gdb_suppress_entire_file "$pf_prefix cannot select executable"
+}
+set test "get target endianness"
+if { [gdb_test_multiple "show endian" "$test" {
+    -re "$en_auto \\\(currently \(big\|little\) endian\\\).*$gdb_prompt" {
+	set endian $expect_out(1,string)
+	pass "$test"
+    }
+}] } {
+    gdb_suppress_entire_file \
+	"$pf_prefix cannot determine executable endianness"
+    set endian ""
+}
+
+# Now check that the automatic endianness is updated
+# according to the executable selected.
+if { [gdb_unload] } {
+    gdb_suppress_entire_file "$pf_prefix cannot unselect executable"
+}
+gdb_test "set endian big" "$en_set big endian" \
+    "override target endianness big"
+gdb_test "set endian auto" "$en_auto \\\(currently big endian\\\)" \
+    "override auto target endianness big"
+if { [gdb_file_cmd $binfile] } {
+    gdb_suppress_entire_file "$pf_prefix cannot select executable"
+}
+gdb_test "show endian" "$en_auto \\\(currently $endian endian\\\)" \
+    "previously big default executable endianness"
+if { [gdb_unload] } {
+    gdb_suppress_entire_file "$pf_prefix cannot unselect executable"
+}
+gdb_test "show endian" "$en_auto \\\(currently $endian endian\\\)" \
+    "previously big default no executable endianness"
+gdb_test "set endian little" "$en_set little endian" \
+    "override target endianness little"
+gdb_test "set endian auto" "$en_auto \\\(currently little endian\\\)" \
+    "override auto target endianness little"
+if { [gdb_file_cmd $binfile] } {
+    gdb_suppress_entire_file "$pf_prefix cannot select executable"
+}
+gdb_test "show endian" "$en_auto \\\(currently $endian endian\\\)" \
+    "previously little default executable endianness"
+if { [gdb_unload] } {
+    gdb_suppress_entire_file "$pf_prefix cannot unselect executable"
+}
+gdb_test "show endian" "$en_auto \\\(currently $endian endian\\\)" \
+    "previously little default no executable endianness"
