diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
index 2886e77..b3a0676 100644
--- a/Lib/test/test_sys.py
+++ b/Lib/test/test_sys.py
@@ -79,6 +79,8 @@
     # Python/pythonrun.c::PyErr_PrintEx() is tricky.
 
     def test_exit(self):
+        import subprocess
+
         self.assertRaises(TypeError, sys.exit, 42, 42)
 
         # call without argument
@@ -133,11 +135,29 @@
             self.fail("no exception")
 
         # test that the exit machinery handles SystemExits properly
-        import subprocess
         rc = subprocess.call([sys.executable, "-c",
                               "raise SystemExit(47)"])
         self.assertEqual(rc, 47)
 
+        def check_exit_message(code, expected):
+            process = subprocess.Popen([sys.executable, "-c", code],
+                                       stderr=subprocess.PIPE)
+            stdout, stderr = process.communicate()
+            self.assertEqual(process.returncode, 1)
+            self.assertTrue(stderr.startswith(expected), stderr)
+
+        # test that stderr buffer if flushed before the exit message is written
+        # into stderr
+        check_exit_message(
+            r'import sys; sys.stderr.write("unflushed,"); sys.exit("message")',
+            b"unflushed,message")
+
+        # test that the exit message is written with backslashreplace error
+        # handler to stderr
+        check_exit_message(
+            r'import sys; sys.exit("surrogates:\uDCFF")',
+            b"surrogates:\\udcff")
+
     def test_getdefaultencoding(self):
         self.assertRaises(TypeError, sys.getdefaultencoding, 42)
         # can't check more than the type, as the user might have changed it
@@ -403,6 +423,24 @@
 
         self.assertRaises(TypeError, sys.intern, S("abc"))
 
+    def test_main_invalid_unicode(self):
+        import locale
+        non_decodable = b"\xff"
+        encoding = locale.getpreferredencoding()
+        try:
+            non_decodable.decode(encoding)
+        except UnicodeDecodeError:
+            pass
+        else:
+            self.skipTest('%r is decodable with encoding %s'
+                % (non_decodable, encoding))
+        code = b'print("' + non_decodable + b'")'
+        p = subprocess.Popen([sys.executable, "-c", code], stderr=subprocess.PIPE)
+        stdout, stderr = p.communicate()
+        self.assertEqual(p.returncode, 1)
+        self.assert_(stderr.startswith(b"UnicodeEncodeError: "
+            b"'utf-8' codec can't encode character '\\udcff' in "
+            b"position 7: surrogates not allowed"), stderr)
 
     def test_sys_flags(self):
         self.assertTrue(sys.flags)
diff --git a/Misc/NEWS b/Misc/NEWS
index 82a13d9..cd196cf 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,9 @@
 Core and Builtins
 -----------------
 
+- PyObject_Dump() encodes unicode objects to utf8 with backslashreplace
+  (instead of strict) error handler to escape surrogates
+
 - Issue #8124: PySys_WriteStdout() and PySys_WriteStderr() don't execute
   indirectly Python signal handlers anymore because mywrite() ignores
   exceptions (KeyboardInterrupt)
diff --git a/Modules/main.c b/Modules/main.c
index eb44aa9..4dcc32d 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -516,18 +516,22 @@
     }
 
     if (command) {
+        char *commandStr;
         PyObject *commandObj = PyUnicode_FromWideChar(
             command, wcslen(command));
         free(command);
-        if (commandObj != NULL) {
-            sts = PyRun_SimpleStringFlags(
-                _PyUnicode_AsString(commandObj), &cf) != 0;
+        if (commandObj != NULL)
+            commandStr = _PyUnicode_AsString(commandObj);
+        else
+            commandStr = NULL;
+        if (commandStr != NULL) {
+            sts = PyRun_SimpleStringFlags(commandStr, &cf) != 0;
+            Py_DECREF(commandObj);
         }
         else {
             PyErr_Print();
             sts = 1;
         }
-        Py_DECREF(commandObj);
     } else if (module) {
         sts = RunModule(module, 1);
     }
diff --git a/Objects/object.c b/Objects/object.c
index 1b8d4e1..b2a5492 100644
--- a/Objects/object.c
+++ b/Objects/object.c
@@ -303,12 +303,15 @@
             }
             else if (PyUnicode_Check(s)) {
                 PyObject *t;
-                t = _PyUnicode_AsDefaultEncodedString(s, NULL);
+                t = PyUnicode_EncodeUTF8(PyUnicode_AS_UNICODE(s),
+                                         PyUnicode_GET_SIZE(s),
+                                         "backslashreplace");
                 if (t == NULL)
                     ret = 0;
                 else {
                     fwrite(PyBytes_AS_STRING(t), 1,
                            PyBytes_GET_SIZE(t), fp);
+                    Py_DECREF(t);
                 }
             }
             else {
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index 031d66f..ec2c6ca 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -1353,7 +1353,11 @@
     if (PyLong_Check(value))
         exitcode = (int)PyLong_AsLong(value);
     else {
+        PyObject *sys_stderr = PySys_GetObject("stderr");
+        if (sys_stderr != NULL)
+            PyObject_CallMethod(sys_stderr, "flush", NULL);
         PyObject_Print(value, stderr, Py_PRINT_RAW);
+        fflush(stderr);
         PySys_WriteStderr("\n");
         exitcode = 1;
     }