diff --git a/capnp/lib/capnp.pyx b/capnp/lib/capnp.pyx
index 41f7b50..1f9ab02 100644
--- a/capnp/lib/capnp.pyx
+++ b/capnp/lib/capnp.pyx
@@ -873,10 +873,10 @@ cdef _to_dict(msg, bint verbose, bint ordered):
 
     return msg
 
+
 cdef _from_list(_DynamicListBuilder msg, list d):
-    cdef size_t count = 0
-    for i in range(len(d)):
-        msg._set(i, d[i])
+    for i, x in enumerate(d):
+        msg._set(i, x)
 
 
 cdef class _DynamicEnum:
diff --git a/test/test_struct.py b/test/test_struct.py
index 563ba02..14aaca2 100644
--- a/test/test_struct.py
+++ b/test/test_struct.py
@@ -107,6 +107,14 @@ def test_builder_set(addressbook):
         person.foo = 'test'
 
 
+def test_builder_set_from_list(all_types):
+    msg = all_types.TestAllTypes.new_message()
+
+    msg.int32List = [0, 1, 2]
+
+    assert list(msg.int32List) == [0, 1, 2]
+
+
 def test_null_str(all_types):
     msg = all_types.TestAllTypes.new_message()