[gdb/python] Handle failure to initialize without exiting
I tried out making python initialization fail by passing an incorrect
PYTHONHOME, and got:
...
$ PYTHONHOME=foo ./gdb.sh -q
Python path configuration:
PYTHONHOME = 'foo'
...
Python initialization failed: \
failed to get the Python codec of the filesystem encoding
Python not initialized
$
...
The relevant part of the code is:
...
static void
gdbpy_initialize (const struct extension_language_defn *extlang)
{
if (!do_start_initialization () && py_isinitialized && PyErr_Occurred ())
gdbpy_print_stack ();
gdbpy_enter enter_py;
...
What happens is:
- gdbpy_enter::gdbpy_enter () is called, where we run into:
'if (!gdb_python_initialized) error (_("Python not initialized"));'
- the error propagates to gdb's toplevel
- gdb print the error and exits.
It seems unnecesssary that we exit gdb. We could continue the
session without python support.
Fix this by:
- bailing out of gdbpy_initialize if !do_start_initialization
- bailing out of finalize_python if !gdb_python_initialized
This gets us instead:
...
$ PYTHONHOME=foo gdb -q
Python path configuration:
PYTHONHOME = 'foo'
...
Python initialization failed: \
failed to get the Python codec of the filesystem encoding
(gdb) python print (1)
Python not initialized
(gdb)
...
Tested on aarch64-linux.
Approved-By: Tom Tromey <tom@tromey.com>
diff --git a/gdb/python/python.c b/gdb/python/python.c
index f9d8e87..3dc56d5 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -2215,6 +2215,9 @@ static struct cmd_list_element *user_show_python_list;
static void
finalize_python (const struct extension_language_defn *ignore)
{
+ if (!gdb_python_initialized)
+ return;
+
struct active_ext_lang_state *previous_active;
/* We don't use ensure_python_env here because if we ever ran the
@@ -2766,8 +2769,21 @@ do_initialize (const struct extension_language_defn *extlang)
static void
gdbpy_initialize (const struct extension_language_defn *extlang)
{
- if (!do_start_initialization () && py_isinitialized && PyErr_Occurred ())
- gdbpy_print_stack ();
+ if (!do_start_initialization ())
+ {
+ if (py_isinitialized)
+ {
+ if (PyErr_Occurred ())
+ gdbpy_print_stack ();
+
+ /* We got no use for the Python interpreter anymore. Finalize it
+ ASAP. */
+ Py_Finalize ();
+ }
+
+ /* Continue with python disabled. */
+ return;
+ }
gdbpy_enter enter_py;
diff --git a/gdb/testsuite/gdb.python/py-failed-init.exp b/gdb/testsuite/gdb.python/py-failed-init.exp
new file mode 100644
index 0000000..1e0c10d
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-failed-init.exp
@@ -0,0 +1,31 @@
+# Copyright 2024 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/>.
+
+require allow_python_tests
+require {!is_remote host}
+
+save_vars { env(PYTHONHOME) } {
+ setenv PYTHONHOME foo
+ clean_restart
+}
+
+gdb_test "python print (1)" \
+ "Python not initialized"
+
+gdb_test_multiple "quit" "" {
+ eof {
+ pass $gdb_test_name
+ }
+}
