diff --git a/jedi/evaluate/__init__.py b/jedi/evaluate/__init__.py
index 041563f0..34635ec8 100644
--- a/jedi/evaluate/__init__.py
+++ b/jedi/evaluate/__init__.py
@@ -341,7 +341,7 @@ class Evaluator(object):
                 if isinstance(comp_for, tree.CompFor):
                     if atom.children[0] == '{':
                         # TODO dict/set comprehensions should be working.
-                        return []
+                        return set()
                     return set([iterable.Comprehension.from_atom(self, atom)])
             return set([iterable.Array(self, atom)])
 
diff --git a/test/completion/comprehensions.py b/test/completion/comprehensions.py
index bec04689..27b3c627 100644
--- a/test/completion/comprehensions.py
+++ b/test/completion/comprehensions.py
@@ -124,6 +124,8 @@ right
 
 #?
 {a - 1 for a in [1]}
+#? int()
+{a - 1: 3 for a in [1]}[0]
 
 # -----------------
 # name resolution in comprehensions.