[review,v3,ARM,Thumb] Fix disassembling bug after reloading a symbol file

diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 8694618..ac7f951 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -89,14 +89,14 @@ 
 
 typedef std::vector<arm_mapping_symbol> arm_mapping_symbol_vec;
 
-struct arm_per_objfile
+struct arm_per_bfd
 {
-  explicit arm_per_objfile (size_t num_sections)
+  explicit arm_per_bfd (size_t num_sections)
   : section_maps (new arm_mapping_symbol_vec[num_sections]),
     section_maps_sorted (new bool[num_sections] ())
   {}
 
-  DISABLE_COPY_AND_ASSIGN (arm_per_objfile);
+  DISABLE_COPY_AND_ASSIGN (arm_per_bfd);
 
   /* Information about mapping symbols ($a, $d, $t) in the objfile.
 
@@ -113,8 +113,8 @@ 
   std::unique_ptr<bool[]> section_maps_sorted;
 };
 
-/* Per-objfile data used for mapping symbols.  */
-static objfile_key<arm_per_objfile> arm_objfile_data_key;
+/* Per-bfd data used for mapping symbols.  */
+static bfd_key<arm_per_bfd> arm_bfd_data_key;
 
 /* The list of available "set arm ..." and "show arm ..." commands.  */
 static struct cmd_list_element *setarmcmdlist = NULL;
@@ -350,7 +350,7 @@ 
   sec = find_pc_section (memaddr);
   if (sec != NULL)
     {
-      arm_per_objfile *data = arm_objfile_data_key.get (sec->objfile);
+      arm_per_bfd *data = arm_bfd_data_key.get (sec->objfile->obfd);
       if (data != NULL)
 	{
 	  unsigned int section_idx = sec->the_bfd_section->index;
@@ -8560,17 +8560,17 @@ 
 			   asymbol *sym)
 {
   const char *name = bfd_asymbol_name (sym);
-  struct arm_per_objfile *data;
+  struct arm_per_bfd *data;
   struct arm_mapping_symbol new_map_sym;
 
   gdb_assert (name[0] == '$');
   if (name[1] != 'a' && name[1] != 't' && name[1] != 'd')
     return;
 
-  data = arm_objfile_data_key.get (objfile);
+  data = arm_bfd_data_key.get (objfile->obfd);
   if (data == NULL)
-    data = arm_objfile_data_key.emplace (objfile,
-					 objfile->obfd->section_count);
+    data = arm_bfd_data_key.emplace (objfile->obfd,
+				     objfile->obfd->section_count);
   arm_mapping_symbol_vec &map
     = data->section_maps[bfd_asymbol_section (sym)->index];
 
diff --git a/gdb/testsuite/gdb.arch/pr25124.S b/gdb/testsuite/gdb.arch/pr25124.S
new file mode 100644
index 0000000..79f82c7
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/pr25124.S
@@ -0,0 +1,35 @@ 
+/* Test proper disassembling of ARM thumb instructions when reloading a symbol
+   file.
+
+   Copyright 2012-2019 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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/>.  */
+
+	.syntax unified
+	.thumb
+	.text
+	.p2align 2
+	.global	main
+	.thumb
+	.thumb_func
+	.type main, %function
+main:
+	bx	pc
+	nop
+.code 32
+	mov	r0, #0
+	bx	lr
+	.size	main, .-main
diff --git a/gdb/testsuite/gdb.arch/pr25124.exp b/gdb/testsuite/gdb.arch/pr25124.exp
new file mode 100644
index 0000000..87b9062
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/pr25124.exp
@@ -0,0 +1,41 @@ 
+# Copyright 2019 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/>.
+
+# Test proper disassembling of ARM thumb instructions when reloading a symbol
+# file.
+
+if {![is_aarch32_target]} then {
+    verbose "Skipping ARM tests."
+    return
+}
+
+standard_testfile .S
+
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable debug] != "" } {
+    untested "failed to compile"
+    return -1
+}
+
+gdb_test "x /i main+8" \
+	"$hex <main\\+8>:\[ \t\]+bx\[ \t\]+lr" \
+	"disassemble thumb instruction (1st try)"
+
+gdb_test "file $binfile" \
+	"Reading symbols from.*" \
+	"reload symbol file"
+
+gdb_test "x /i main+8" \
+	"$hex <main\\+8>:\[ \t\]+bx\[ \t\]+lr" \
+	"disassemble thumb instruction (2nd try)"