diff -r f1539e7607e4 Lib/site.py
--- a/Lib/site.py	Sat Mar 19 13:16:52 2016 +0200
+++ b/Lib/site.py	Sun Mar 20 15:07:20 2016 +0100
@@ -131,13 +131,12 @@
 
 
 def _init_pathinfo():
-    """Return a set containing all existing directory entries from sys.path"""
+    """Return a set containing all existing entries from sys.path"""
     d = set()
     for dir in sys.path:
         try:
-            if os.path.isdir(dir):
-                dir, dircase = makepath(dir)
-                d.add(dircase)
+            dir, dircase = makepath(dir)
+            d.add(dircase)
         except TypeError:
             continue
     return d
diff -r f1539e7607e4 Lib/test/test_site.py
--- a/Lib/test/test_site.py	Sat Mar 19 13:16:52 2016 +0200
+++ b/Lib/test/test_site.py	Sun Mar 20 15:07:20 2016 +0100
@@ -73,9 +73,10 @@
             self.assertEqual(os.path.normcase(abs_dir), norm_dir)
 
     def test_init_pathinfo(self):
+        sys.path.extend(("./test.zip", "./testsub.zip/subpach"))
         dir_set = site._init_pathinfo()
         for entry in [site.makepath(path)[1] for path in sys.path
-                        if path and os.path.isdir(path)]:
+                        if path]:
             self.assertIn(entry, dir_set,
                           "%s from sys.path not found in set returned "
                           "by _init_pathinfo(): %s" % (entry, dir_set))