diff -r c4e4886c6052 Lib/test/test_zipfile.py
--- a/Lib/test/test_zipfile.py	Fri Jan 22 16:39:02 2016 -0800
+++ b/Lib/test/test_zipfile.py	Sat Jan 23 05:24:19 2016 -0500
@@ -1428,6 +1428,33 @@
             # testzip returns the name of the first corrupt file, or None
             self.assertIsNone(zipf.testzip())
 
+    def test_lazy_init_info_slot_attributes(self):
+        """Check that ZipInfo slots can be lazily initialized."""
+        zinfo = zipfile.ZipInfo()
+        self.assertIsNone(zinfo.header_offset)
+        self.assertIsNone(zinfo.CRC)
+        self.assertIsNone(zinfo.compress_size)
+        self.assertIsNone(zinfo.file_size)
+        self.assertIsNone(zinfo._raw_time)
+
+    def test_nonslot_info_attribute_access_still_raises_error(self):
+        """Check that accessing a non-slot ZipInfo attribute still
+        raises AttributeError.
+
+        """
+        self.assertNotIn("i_am_not_herbert", zipfile.ZipInfo.__slots__)
+        zinfo = zipfile.ZipInfo()
+        self.assertRaises(AttributeError, getattr, zinfo, "i_am_not_herbert")
+
+    def test_repr_with_noninitialized_info_slot_attributes(self):
+        """Check that non-initialized slot attributes no longer cause
+        AttributeError when a ZipInfo object is repr()'ed.
+
+        """
+        zinfo = zipfile.ZipInfo()
+        r = repr(zinfo)
+        self.assertIn("file_size=None", r)
+
     def tearDown(self):
         unlink(TESTFN)
         unlink(TESTFN2)
diff -r c4e4886c6052 Lib/zipfile.py
--- a/Lib/zipfile.py	Fri Jan 22 16:39:02 2016 -0800
+++ b/Lib/zipfile.py	Sat Jan 23 05:24:19 2016 -0500
@@ -353,12 +353,20 @@
         self.volume = 0                 # Volume number of file header
         self.internal_attr = 0          # Internal attributes
         self.external_attr = 0          # External file attributes
-        # Other attributes are set by class ZipFile:
+        # Other attributes are set by class ZipFile: (but see __getattr__)
         # header_offset         Byte offset to the file header
         # CRC                   CRC-32 of the uncompressed file
         # compress_size         Size of the compressed file
         # file_size             Size of the uncompressed file
 
+    def __getattr__(self, name):
+        # Prevent unexpected AttributeError for any slot that might be accessed
+        # before it is initialized by lazily initializing it to None
+        # - only happens once
+        # - attributes NOT defined as slots will still raise AttributeError
+        # - future-proof, and subclasses will inherit the benefit, too
+        setattr(self, name, None)
+
     def __repr__(self):
         result = ['<%s filename=%r' % (self.__class__.__name__, self.filename)]
         if self.compress_type != ZIP_STORED: