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@@ -1,193 +0,0 @@
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-From 8342feee01e4e8d38affcf35e47ad900567f42e0 Mon Sep 17 00:00:00 2001
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-From: Kevin Buettner <kevinb@redhat.com>
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-Date: Wed, 27 May 2020 20:05:40 -0700
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-Subject: [PATCH] Fix Python3.9 related runtime problems
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-
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-Python3.9b1 is now available on Rawhide. GDB w/ Python 3.9 support
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-can be built using the configure switch -with-python=/usr/bin/python3.9.
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-
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-Attempting to run gdb/Python3.9 segfaults on startup:
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-
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- #0 0x00007ffff7b0582c in PyEval_ReleaseLock () from /lib64/libpython3.9.so.1.0
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- #1 0x000000000069ccbf in do_start_initialization ()
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- at worktree-test1/gdb/python/python.c:1789
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- #2 _initialize_python ()
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- at worktree-test1/gdb/python/python.c:1877
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- #3 0x00000000007afb0a in initialize_all_files () at init.c:237
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- ...
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-
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-Consulting the the documentation...
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-
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-https://docs.python.org/3/c-api/init.html
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-
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-...we find that PyEval_ReleaseLock() has been deprecated since version
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-3.2. It recommends using PyEval_SaveThread or PyEval_ReleaseThread()
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-instead. In do_start_initialization, in gdb/python/python.c, we
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-can replace the calls to PyThreadState_Swap() and PyEval_ReleaseLock()
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-with a single call to PyEval_SaveThread. (Thanks to Keith Seitz
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-for working this out.)
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-
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-With that in place, GDB gets a little bit further. It still dies
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-on startup, but the backtrace is different:
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-
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- #0 0x00007ffff7b04306 in PyOS_InterruptOccurred ()
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- from /lib64/libpython3.9.so.1.0
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- #1 0x0000000000576e86 in check_quit_flag ()
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- at worktree-test1/gdb/extension.c:776
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- #2 0x0000000000576f8a in set_active_ext_lang (now_active=now_active@entry=0x983c00 <extension_language_python>)
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- at worktree-test1/gdb/extension.c:705
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- #3 0x000000000069d399 in gdbpy_enter::gdbpy_enter (this=0x7fffffffd2d0,
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- gdbarch=0x0, language=0x0)
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- at worktree-test1/gdb/python/python.c:211
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- #4 0x0000000000686e00 in python_new_inferior (inf=0xddeb10)
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- at worktree-test1/gdb/python/py-inferior.c:251
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- #5 0x00000000005d9fb9 in std::function<void (inferior*)>::operator()(inferior*) const (__args#0=<optimized out>, this=0xccad20)
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- at /usr/include/c++/10/bits/std_function.h:617
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- #6 gdb::observers::observable<inferior*>::notify (args#0=0xddeb10,
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- this=<optimized out>)
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- at worktree-test1/gdb/../gdbsupport/observable.h:106
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- #7 add_inferior_silent (pid=0)
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- at worktree-test1/gdb/inferior.c:113
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- #8 0x00000000005dbcb8 in initialize_inferiors ()
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- at worktree-test1/gdb/inferior.c:947
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- ...
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-
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-We checked with some Python Developers and were told that we should
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-acquire the GIL prior to calling any Python C API function. We
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-definitely don't have the GIL for calls of PyOS_InterruptOccurred().
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-
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-I moved class_gdbpy_gil earlier in the file and use it in
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-gdbpy_check_quit_flag() to acquire (and automatically release) the
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-GIL.
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-
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-With those changes in place, I was able to run to a GDB prompt. But,
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-when trying to quit, it segfaulted again due to due to some other
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-problems with gdbpy_check_quit_flag():
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-
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- Thread 1 "gdb" received signal SIGSEGV, Segmentation fault.
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- 0x00007ffff7bbab0c in new_threadstate () from /lib64/libpython3.9.so.1.0
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- (top-gdb) bt 8
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- #0 0x00007ffff7bbab0c in new_threadstate () from /lib64/libpython3.9.so.1.0
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- #1 0x00007ffff7afa5ea in PyGILState_Ensure.cold ()
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- from /lib64/libpython3.9.so.1.0
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- #2 0x000000000069b58c in gdbpy_gil::gdbpy_gil (this=<synthetic pointer>)
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- at worktree-test1/gdb/python/python.c:278
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- #3 gdbpy_check_quit_flag (extlang=<optimized out>)
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- at worktree-test1/gdb/python/python.c:278
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- #4 0x0000000000576e96 in check_quit_flag ()
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- at worktree-test1/gdb/extension.c:776
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- #5 0x000000000057700c in restore_active_ext_lang (previous=0xe9c050)
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- at worktree-test1/gdb/extension.c:729
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- #6 0x000000000088913a in do_my_cleanups (
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- pmy_chain=0xc31870 <final_cleanup_chain>,
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- old_chain=0xae5720 <sentinel_cleanup>)
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- at worktree-test1/gdbsupport/cleanups.cc:131
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- #7 do_final_cleanups ()
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- at worktree-test1/gdbsupport/cleanups.cc:143
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-
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-In this case, we're trying to call a Python C API function after
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-Py_Finalize() has been called from finalize_python(). I made
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-finalize_python set gdb_python_initialized to false and then cause
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-check_quit_flag() to return early when it's false.
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-
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-With these changes in place, GDB seems to be working again with
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-Python3.9b1. I think it likely that there are other problems lurking.
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-I wouldn't be surprised to find that there are other calls into Python
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-where we don't first make sure that we have the GIL. Further changes
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-may well be needed.
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-
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-I see no regressions testing on Rawhide using a GDB built with the
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-default Python version (3.8.3) versus one built using Python 3.9b1.
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-
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-I've also tested on Fedora 28, 29, 30, 31, and 32 (all x86_64) using
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-the default (though updated) system installed versions of Python on
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-those OSes. This means that I've tested against Python versions
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-2.7.15, 2.7.17, 2.7.18, 3.7.7, 3.8.2, and 3.8.3. In each case GDB
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-still builds without problem and shows no regressions after applying
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-this patch.
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-
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-gdb/ChangeLog:
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-
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-2020-MM-DD Kevin Buettner <kevinb@redhat.com>
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- Keith Seitz <keiths@redhat.com>
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-
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- * python/python.c (do_start_initialization): For Python 3.9 and
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- later, call PyEval_SaveThread instead of PyEval_ReleaseLock.
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- (class gdbpy_gil): Move to earlier in file.
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- (finalize_python): Set gdb_python_initialized.
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- (gdbpy_check_quit_flag): Acquire GIL via gdbpy_gil. Return early
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- when not initialized.
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-
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-[import into Buildroot, removing ChangeLog change to avoid conflict]
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-Signed-off-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
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----
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- gdb/python/python.c | 32 ++++++++++++++++++++++++++++++--
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- 1 file changed, 30 insertions(+), 2 deletions(-)
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-
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-diff --git a/gdb/python/python.c b/gdb/python/python.c
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-index b00b70be85b..0eee3f0397c 100644
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---- a/gdb/python/python.c
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-+++ b/gdb/python/python.c
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-@@ -268,6 +268,30 @@ ensure_python_env (struct gdbarch *gdbarch,
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- return make_cleanup (restore_python_env, env);
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- }
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-
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-+/* A helper class to save and restore the GIL, but without touching
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-+ the other globals that are handled by gdbpy_enter. */
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-+
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-+class gdbpy_gil
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-+{
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-+public:
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-+
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-+ gdbpy_gil ()
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-+ : m_state (PyGILState_Ensure ())
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-+ {
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-+ }
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-+
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-+ ~gdbpy_gil ()
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-+ {
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-+ PyGILState_Release (m_state);
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-+ }
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-+
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-+ DISABLE_COPY_AND_ASSIGN (gdbpy_gil);
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-+
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-+private:
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-+
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-+ PyGILState_STATE m_state;
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-+};
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-+
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- /* Set the quit flag. */
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-
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- static void
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-@@ -281,6 +305,10 @@ gdbpy_set_quit_flag (const struct extension_language_defn *extlang)
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- static int
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- gdbpy_check_quit_flag (const struct extension_language_defn *extlang)
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- {
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-+ if (!gdb_python_initialized)
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-+ return 0;
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-+
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-+ gdbpy_gil gil;
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- return PyOS_InterruptOccurred ();
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- }
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-
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-@@ -1620,6 +1648,7 @@ finalize_python (void *ignore)
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-
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- Py_Finalize ();
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-
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-+ gdb_python_initialized = false;
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- restore_active_ext_lang (previous_active);
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- }
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- #endif
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-@@ -1854,8 +1883,7 @@ message == an error message without a stack will be printed."),
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- goto fail;
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-
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- /* Release the GIL while gdb runs. */
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-- PyThreadState_Swap (NULL);
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-- PyEval_ReleaseLock ();
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-+ PyEval_SaveThread ();
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-
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- make_final_cleanup (finalize_python, NULL);
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-
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---
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-2.31.1
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-
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Yann E. MORIN