diff --git a/jedi/builtin.py b/jedi/builtin.py
index a51525b1..14054195 100644
--- a/jedi/builtin.py
+++ b/jedi/builtin.py
@@ -245,8 +245,6 @@ class Parser(CachedModule):
             stmts = {}
             members = {}
             for n in names:
-                if '__' in n and n not in mixin_funcs:
-                    continue
                 try:
                     # this has a builtin_function_or_method
                     exe = getattr(scope, n)
diff --git a/jedi/parsing.py b/jedi/parsing.py
index 4885cd90..67871f8c 100644
--- a/jedi/parsing.py
+++ b/jedi/parsing.py
@@ -1316,7 +1316,8 @@ class PyFuzzyParser(object):
                 if annotation:
                     param.add_annotation(annotation)
 
-            if param:
+            # params without vars are usually syntax errors.
+            if param and (param.set_vars or param.used_vars):
                 param.position_nr = pos
                 names.append(param)
                 pos += 1