Test that native targets can read a tdesc without a process attached.

This ensures that 'unset tdesc filename' does not generate any output
on a "bare" native target inferior without an attached process.

gdb/testsuite/gdb.base/native-target-noproc-tdesc.exp

@@ -0,0 +1,27 @@
+# Copyright 2023 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 "unset tdesc filename" without an attached process on native
+# targets.
+
+clean_restart
+
+require have_native_target
+
+# Manually attach the native target
+gdb_test "target native" "Done.  Use the \"run\" command to start a process."
+
+# Load a default target description
+gdb_test_no_output "unset tdesc filename"