diff --git a/update_engine.gyp b/update_engine.gyp
index e6add56..8dd5d2d 100644
--- a/update_engine.gyp
+++ b/update_engine.gyp
@@ -280,6 +280,7 @@
         'payload_generator/extent_mapper.cc',
         'payload_generator/filesystem_iterator.cc',
         'payload_generator/full_update_generator.cc',
+        'payload_generator/graph_types.cc',
         'payload_generator/graph_utils.cc',
         'payload_generator/inplace_generator.cc',
         'payload_generator/metadata.cc',