diff --git a/Check.hs b/Check.hs
index 24fd974..3ae4929 100644
--- a/Check.hs
+++ b/Check.hs
@@ -23,6 +23,10 @@ check opt cradle fileName = withGHC fileName $ checkIt `gcatch` handleErrMsg
     checkIt = do
         readLog <- initializeFlagsWithCradle opt cradle options True
         setTargetFile fileName
+        -- To check TH, a session module graph is necessary.
+        -- "load" sets a session module graph using "depanal".
+        -- But we have to set "-fno-code" to DynFlags before "load".
+        -- So, this is necessary redundancy.
         slow <- needsTemplateHaskell <$> depanal [] False
         when slow setSlowDynFlags
         void $ load LoadAllTargets