diff -r 2f0716009132 Lib/test/test_os.py
--- a/Lib/test/test_os.py	Tue Jul 12 18:24:25 2016 -0400
+++ b/Lib/test/test_os.py	Fri Jul 15 01:38:35 2016 +0800
@@ -3145,18 +3145,24 @@
         self.assertTrue(issubclass(self.PathLike, os.PathLike))
         self.assertTrue(isinstance(self.PathLike(), os.PathLike))
 
-        with self.assertRaises(TypeError):
-            self.fspath(self.PathLike(42))
-
     def test_garbage_in_exception_out(self):
         vapor = type('blah', (), {})
         for o in int, type, os, vapor():
             self.assertRaises(TypeError, self.fspath, o)
 
     def test_argument_required(self):
-        with self.assertRaises(TypeError):
-            self.fspath()
-
+        self.assertRaises(TypeError, self.fspath)
+
+    def test_bad_pathlike(self):
+        # bad __fspath__ return value, not str or bytes object
+        self.assertRaises(TypeError, self.fspath, self.PathLike(42))
+        # __fspath__ attribute that is not callable
+        c = type('foo', (), {})
+        c.__fspath__ = 1
+        self.assertRaises(TypeError, self.fspath, c())
+        # __fspath__ method raises exceptions
+        c.__fspath__ = lambda self: self.__not_exist
+        self.assertRaises(AttributeError, self.fspath, c())
 
 # Only test if the C version is provided, otherwise TestPEP519 already tested
 # the pure Python implementation.
diff -r 2f0716009132 Modules/posixmodule.c
--- a/Modules/posixmodule.c	Tue Jul 12 18:24:25 2016 -0400
+++ b/Modules/posixmodule.c	Fri Jul 15 01:38:35 2016 +0800
@@ -12319,6 +12319,8 @@
 
     path_repr = PyObject_CallFunctionObjArgs(func, NULL);
     Py_DECREF(func);
+    if (NULL == path_repr)
+        return NULL;
     if (!(PyUnicode_Check(path_repr) || PyBytes_Check(path_repr))) {
         PyErr_Format(PyExc_TypeError,
                      "expected %.200s.__fspath__() to return str or bytes, "