Fix an attribute error in static analysis code.

jedi/evaluate/compiled/__init__.py

@@ -40,6 +40,7 @@ class CompiledObject(Base):
     # comply with the parser
     start_pos = 0, 0
     path = None  # modules have this attribute - set it to None.
+    used_names = {}  # To be consistent with modules.
 
     def __init__(self, obj, parent=None):
         self.obj = obj

test/static_analysis/attribute_error.py

@@ -111,3 +111,9 @@ import import_tree
 
 import_tree.a
 import_tree.b
+
+# This is something that raised an error, because it was using a complex
+# mixture of Jedi fakes and compiled objects.
+import _sre
+#! 15 attribute-error
+_sre.compile().not_existing