From 4e90febbaa20d72202637ad7e2b44ca2fe150bea Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Fri, 6 Mar 2020 18:59:52 +0000
Subject: [PATCH] RHEL 7: python: Check for _Py_IsFinalizing.

This symbol is not present in Python 2.7 or 3.6.  It's not really
necessary to call this, it just avoids a crash in certain corner cases
when the interpreter is shutting down.  So make the call conditional
on the function existing.

Fixes commit e6f9e0b0f6a588abbc35854e8ad862207b6e26ec.
---
 m4/guestfs-python.m4 | 12 ++++++++++++
 python/handle.c      |  2 ++
 2 files changed, 14 insertions(+)

diff --git a/m4/guestfs-python.m4 b/m4/guestfs-python.m4
index 2e736875c..0a49b7fc8 100644
--- a/m4/guestfs-python.m4
+++ b/m4/guestfs-python.m4
@@ -88,6 +88,18 @@ AS_IF([test "x$enable_python" != "xno"],[
         AC_MSG_RESULT([$PYTHON_EXT_SUFFIX])
 
         AC_CHECK_PROGS([PYCODESTYLE],[pycodestyle],[no])
+
+        dnl Look for some optional symbols in libpython.
+        old_LIBS="$LIBS"
+
+        PYTHON_BLDLIBRARY=`$PYTHON -c "import distutils.sysconfig; \
+                                       print (distutils.sysconfig.get_config_var('BLDLIBRARY'))"`
+        AC_CHECK_LIB([c],[_Py_IsFinalizing],
+                     [AC_DEFINE([HAVE_PY_ISFINALIZING],1,
+                                [Found _Py_IsFinalizing in libpython.])],
+                     [],[$PYTHON_BLDLIBRARY])
+
+        LIBS="$old_LIBS"
     fi
 
     AC_SUBST(PYTHON_PREFIX)
diff --git a/python/handle.c b/python/handle.c
index 21077bba9..2db021f1b 100644
--- a/python/handle.c
+++ b/python/handle.c
@@ -121,8 +121,10 @@ guestfs_int_py_event_callback_wrapper (guestfs_h *g,
   PyObject *py_r;
   int threads_initialized = PyEval_ThreadsInitialized ();
 
+#ifdef HAVE_PY_ISFINALIZING
   if (_Py_IsFinalizing ())
     return;
+#endif
 
   if (threads_initialized)
     py_save = PyGILState_Ensure ();