Index: gdb/gdb/NEWS
===================================================================
--- gdb.orig/gdb/NEWS 2018-05-14 04:01:41.000000000 +0100
+++ gdb/gdb/NEWS 2018-05-30 20:58:03.772196107 +0100
@@ -3,6 +3,12 @@
*** Changes since GDB 8.1
+* The endianness used with the 'set endian auto' mode in the absence of
+ an executable selected for debugging is now the last endianness chosen
+ either by one of the 'set endian big' and 'set endian little' commands
+ or by inferring from the last executable used, rather than the startup
+ default.
+
* The commands 'info variables/functions/types' now show the source line
numbers of symbol definitions when available.
Index: gdb/gdb/arch-utils.c
===================================================================
--- gdb.orig/gdb/arch-utils.c 2018-05-14 04:01:42.045923841 +0100
+++ gdb/gdb/arch-utils.c 2018-05-30 17:13:21.295622268 +0100
@@ -768,6 +768,8 @@ 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: gdb/gdb/doc/gdb.texinfo
===================================================================
--- gdb.orig/gdb/doc/gdb.texinfo 2018-05-30 17:11:24.000000000 +0100
+++ gdb/gdb/doc/gdb.texinfo 2018-05-30 17:49:24.224267380 +0100
@@ -20308,6 +20308,15 @@ Display @value{GDBN}'s current idea of t
@end table
+If the @code{set endian auto} mode is in effect and no executable has
+been selected, then the endianness used is the last one chosen either
+by one of the @code{set endian big} and @code{set endian little}
+commands or by inferring from the last executable used. If no
+endianness has been previously chosen, then the default for this mode
+is inferred from the target @value{GDBN} has been built for, and is
+@code{little} if the name of the target CPU has an @code{el} suffix
+and @code{big} otherwise.
+
Note that these commands merely adjust interpretation of symbolic
data on the host, and that they have absolutely no effect on the
target system.
Index: gdb/gdb/testsuite/gdb.base/endian.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ gdb/gdb/testsuite/gdb.base/endian.c 2018-05-30 21:12:39.342971368 +0100
@@ -0,0 +1,22 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright (C) 2018 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 . */
+
+int
+main (void)
+{
+ return 0;
+}
Index: gdb/gdb/testsuite/gdb.base/endian.exp
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ gdb/gdb/testsuite/gdb.base/endian.exp 2018-05-30 21:12:46.798719867 +0100
@@ -0,0 +1,96 @@
+# Copyright (C) 2018 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 .
+
+# 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"