diff --git a/CHANGES b/CHANGES
index 03194421..dbb5947a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -3,6 +3,21 @@ Flask Changelog
 
 Here you can see the full list of changes between each Flask release.
 
+Version 0.13
+------------
+
+Major release, unreleased
+
+- Make `app.run()` into a noop if a Flask application is run from the
+  development server on the command line.  This avoids some behavior that
+  was confusing to debug for newcomers.
+- Change default configuration `JSONIFY_PRETTYPRINT_REGULAR=False`. jsonify()
+  method returns compressed response by default, and pretty response in
+  debug mode.
+- Call `ctx.auto_pop` with the exception object instead of `None`, in the
+  event that a `BaseException` such as `KeyboardInterrupt` is raised in a
+  request handler.
+
 Version 0.12.1
 --------------
 
diff --git a/flask/app.py b/flask/app.py
index 942992dc..1404e17e 100644
--- a/flask/app.py
+++ b/flask/app.py
@@ -1983,6 +1983,9 @@ class Flask(_PackageBoundObject):
             except Exception as e:
                 error = e
                 response = self.handle_exception(e)
+            except:
+                error = sys.exc_info()[1]
+                raise
             return response(environ, start_response)
         finally:
             if self.should_ignore_error(error):
diff --git a/tests/test_basic.py b/tests/test_basic.py
index be3d5edd..c5ec9f5c 100644
--- a/tests/test_basic.py
+++ b/tests/test_basic.py
@@ -791,6 +791,23 @@ def test_error_handling_processing():
         assert resp.data == b'internal server error'
 
 
+def test_baseexception_error_handling():
+    app = flask.Flask(__name__)
+    app.config['LOGGER_HANDLER_POLICY'] = 'never'
+
+    @app.route('/')
+    def broken_func():
+        raise KeyboardInterrupt()
+
+    with app.test_client() as c:
+        with pytest.raises(KeyboardInterrupt):
+            c.get('/')
+
+        ctx = flask._request_ctx_stack.top
+        assert ctx.preserved
+        assert type(ctx._preserved_exc) is KeyboardInterrupt
+
+
 def test_before_request_and_routing_errors():
     app = flask.Flask(__name__)