diff --git a/stepmania/src/Makefile.am b/stepmania/src/Makefile.am
index ab1ecf1f20..116261f36f 100644
--- a/stepmania/src/Makefile.am
+++ b/stepmania/src/Makefile.am
@@ -88,6 +88,7 @@ endif
 
 DataStructures = \
 ActorCommands.cpp ActorCommands.h Attack.cpp Attack.h AutoKeysounds.cpp AutoKeysounds.h \
+AdjustSync.cpp AdjustSync.h \
 BackgroundUtil.cpp BackgroundUtil.h \
 BannerCache.cpp BannerCache.h CatalogXml.cpp CatalogXml.h \
 Character.cpp Character.h \