diff --git a/SSTG.cabal b/SSTG.cabal
--- a/SSTG.cabal
+++ b/SSTG.cabal
@@ -1,5 +1,5 @@
 name:                SSTG
-version:             0.1.0.9
+version:             0.1.1.0
 synopsis:            STG Symbolic Execution
 description:         Prototype of STG-based Symbolic Execution for Haskell.
 homepage:            https://github.com/AntonXue/SSTG#readme
diff --git a/src/SSTG/Core/Execution/Rules.hs b/src/SSTG/Core/Execution/Rules.hs
--- a/src/SSTG/Core/Execution/Rules.hs
+++ b/src/SSTG/Core/Execution/Rules.hs
@@ -458,12 +458,12 @@
 
   -- Rule Apply Frame Create Function Thunk
   | Evaluate (FunApp fun args) locals <- code
-  , Just (_, hobj)          <- vlookupHeap fun locals globals heap
-  , FunObj [] expr fun_locs <- hobj =
+  , Just (_, hobj) <- vlookupHeap fun locals globals heap
+  , FunObj [] _ _  <- hobj =
     let frame = ApplyFrame args locals
     in Just (RuleApplyCFunThunk
             ,[state { state_stack = pushStack frame stack
-                    , state_code  = Evaluate expr fun_locs }])
+                    , state_code  = Evaluate (Atom (VarAtom fun)) locals }])
 
   -- Rule Apply Frame Create Function Over Application
   | Evaluate (FunApp fun args) locals <- code