bpo-35504: Fix segfaults and SystemErrors when deleting certain attrs. (GH-11175)

5 files changed, 32 insertions, 4 deletions

diff --git a/Lib/test/multibytecodec_support.py b/Lib/test/multibytecodec_support.py
index 813b7aa..cca8af6 100644
--- a/Lib/test/multibytecodec_support.py
+++ b/Lib/test/multibytecodec_support.py
@@ -277,6 +277,11 @@ class TestBase:
         writer = self.writer(stream)
         writer.reset()
 
+    def test_incrementalencoder_del_segfault(self):
+        e = self.incrementalencoder()
+        with self.assertRaises(AttributeError):
+            del e.errors
+
 
 class TestBase_Mapping(unittest.TestCase):
     pass_enctest = []
diff --git a/Lib/test/test_asyncio/test_futures.py b/Lib/test/test_asyncio/test_futures.py
index 3339356..2e4583d 100644
--- a/Lib/test/test_asyncio/test_futures.py
+++ b/Lib/test/test_asyncio/test_futures.py
@@ -570,6 +570,13 @@ class CFutureTests(BaseFutureTests, test_utils.TestCase):
     except AttributeError:
         cls = None
 
+    def test_future_del_segfault(self):
+        fut = self._new_future(loop=self.loop)
+        with self.assertRaises(AttributeError):
+            del fut._asyncio_future_blocking
+        with self.assertRaises(AttributeError):
+            del fut._log_traceback
+
 
 @unittest.skipUnless(hasattr(futures, '_CFuture'),
                      'requires the C _asyncio module')
diff --git a/Lib/test/test_asyncio/test_tasks.py b/Lib/test/test_asyncio/test_tasks.py
index c65d1f2..22f14f8 100644
--- a/Lib/test/test_asyncio/test_tasks.py
+++ b/Lib/test/test_asyncio/test_tasks.py
@@ -2546,6 +2546,15 @@ class CTask_CFuture_Tests(BaseTaskTests, SetMethodsTest,
             self.loop.run_until_complete(task)
         self.assertAlmostEqual(gettotalrefcount() - refs_before, 0, delta=10)
 
+    def test_del__log_destroy_pending_segfault(self):
+        @asyncio.coroutine
+        def coro():
+            pass
+        task = self.new_task(self.loop, coro())
+        self.loop.run_until_complete(task)
+        with self.assertRaises(AttributeError):
+            del task._log_destroy_pending
+
 
 @unittest.skipUnless(hasattr(futures, '_CFuture') and
                      hasattr(tasks, '_CTask'),
diff --git a/Lib/test/test_frame.py b/Lib/test/test_frame.py
index fd79508..d6aa283 100644
--- a/Lib/test/test_frame.py
+++ b/Lib/test/test_frame.py
@@ -109,10 +109,7 @@ class ClearTest(unittest.TestCase):
             self.assertIs(None, wr())
 
 
-class FrameLocalsTest(unittest.TestCase):
-    """
-    Tests for the .f_locals attribute.
-    """
+class FrameAttrsTest(unittest.TestCase):
 
     def make_frames(self):
         def outer():
@@ -159,6 +156,11 @@ class FrameLocalsTest(unittest.TestCase):
         self.assertEqual(outer.f_locals, {})
         self.assertEqual(inner.f_locals, {})
 
+    def test_f_lineno_del_segfault(self):
+        f, _, _ = self.make_frames()
+        with self.assertRaises(AttributeError):
+            del f.f_lineno
+
 
 class ReprTest(unittest.TestCase):
     """
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index 14352ff..dc353c1 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -3663,6 +3663,11 @@ class CTextIOWrapperTest(TextIOWrapperTest):
             t2.buddy = t1
         support.gc_collect()
 
+    def test_del__CHUNK_SIZE_SystemError(self):
+        t = self.TextIOWrapper(self.BytesIO(), encoding='ascii')
+        with self.assertRaises(AttributeError):
+            del t._CHUNK_SIZE
+
 
 class PyTextIOWrapperTest(TextIOWrapperTest):
     io = pyio