1 files changed, 1 insertions, 0 deletions
diff --git a/src/pch.h b/src/pch.h
index b7c5d695..8e8d33f7 100644
--- a/src/pch.h
+++ b/src/pch.h
@@ -22,6 +22,7 @@
 #include <string.h>
 #include <string>
 #include <tuple>
+#include <unordered_set>
 #include <utility>
 #include <vector>
 #include <wchar.h>