diff --git a/jedi/evaluate/base_context.py b/jedi/evaluate/base_context.py
index 055a62a8..7d9b2e87 100644
--- a/jedi/evaluate/base_context.py
+++ b/jedi/evaluate/base_context.py
@@ -300,6 +300,17 @@ class ContextSet(BaseContextSet):
     def get_item(self, *args, **kwargs):
         return ContextSet.from_sets(_getitem(c, *args, **kwargs) for c in self._set)
 
+    def try_merge(self, function_name):
+        context_set = self.__class__()
+        for c in self._set:
+            try:
+                method = getattr(c, function_name)
+            except AttributeError:
+                pass
+            else:
+                context_set |= method()
+        return context_set
+
 
 NO_CONTEXTS = ContextSet()
 
diff --git a/jedi/evaluate/context/function.py b/jedi/evaluate/context/function.py
index 8eded724..f0ed1c8d 100644
--- a/jedi/evaluate/context/function.py
+++ b/jedi/evaluate/context/function.py
@@ -112,7 +112,7 @@ class FunctionContext(use_metaclass(CachedMetaClass, AbstractFunction)):
 
     def py__call__(self, arguments, need_param_match=False):
         function_execution = self.get_function_execution(arguments)
-        if need_param_match and function_execution.matches_signature():
+        if need_param_match and not function_execution.matches_signature():
             return NO_CONTEXTS
         return function_execution.infer()
 
diff --git a/jedi/evaluate/context/instance.py b/jedi/evaluate/context/instance.py
index d8827489..2d97fbb8 100644
--- a/jedi/evaluate/context/instance.py
+++ b/jedi/evaluate/context/instance.py
@@ -274,7 +274,6 @@ class TreeInstance(AbstractInstanceContext):
                 # First check if the signature even matches, if not we don't
                 # need to infer anything.
                 continue
-            print(bound)
             context_set = define_type_vars_for_execution(
                 ContextSet(self.class_context),
                 execution,
diff --git a/jedi/evaluate/context/typing.py b/jedi/evaluate/context/typing.py
index cdc6458b..7b3f5408 100644
--- a/jedi/evaluate/context/typing.py
+++ b/jedi/evaluate/context/typing.py
@@ -406,7 +406,7 @@ class TypeVar(_BaseTypingContext):
             return ContextSet.from_sets(
                 l.infer() for l in self._constraints_lazy_contexts
             )
-        debug.warning('Tried to infer a TypeVar without a given type')
+        debug.warning('Tried to infer the TypeVar %r without a given type', self._var_name)
         return NO_CONTEXTS
 
     @property
diff --git a/jedi/evaluate/pep0484.py b/jedi/evaluate/pep0484.py
index 2378f984..70c90afd 100644
--- a/jedi/evaluate/pep0484.py
+++ b/jedi/evaluate/pep0484.py
@@ -256,14 +256,18 @@ def _infer_type_vars_for_execution(execution_context, annotation_dict):
             annotation_node = annotation_dict[executed_param.string_name]
         except KeyError:
             continue
-        if executed_param._param_node.star_count:  # TODO remove this.
-            continue
 
         annotation_variables = find_unknown_type_vars(context, annotation_node)
         if annotation_variables:
             # Infer unknown type var
             annotation_context_set = context.eval_node(annotation_node)
+            star_count = executed_param._param_node.star_count
             actual_context_set = executed_param.infer(use_hints=False)
+            if star_count == 1:
+                actual_context_set = actual_context_set.merge_types_of_iterate()
+            elif star_count == 2:
+                # TODO _dict_values is not public.
+                actual_context_set = actual_context_set.try_merge('_dict_values')
             for ann in annotation_context_set:
                 _merge_type_var_dicts(
                     annotation_variable_results,