diff --git a/src/fsharp/Optimizer.fs b/src/fsharp/Optimizer.fs
index 340c269b28e..946e241f74a 100644
--- a/src/fsharp/Optimizer.fs
+++ b/src/fsharp/Optimizer.fs
@@ -2582,22 +2582,21 @@ and TryInlineApplication cenv env (_f0',finfo) (tyargs: TType list,args: Expr li
 //------------------------------------------------------------------------- 
 
 and OptimizeApplication cenv env (f0,f0ty,tyargs,args,m) =
-    let f0',finfo = OptimizeExpr cenv env f0 
     // trying to devirtualize
     match TryDevirtualizeApplication cenv env (f0,tyargs,args,m) with 
     | Some res -> 
         // devirtualized
         res
     | None -> 
-
-    match TryInlineApplication cenv env (f0',finfo) (tyargs,args,m) with 
+    let newf0,finfo = OptimizeExpr cenv env f0
+    match TryInlineApplication cenv env (newf0,finfo) (tyargs,args,m) with 
     | Some res -> 
         // inlined
         res
     | None -> 
 
     let shapes = 
-        match f0' with 
+        match newf0 with 
         | Expr.Val(vref,_,_) ->
             match vref.ValReprInfo with
             | Some(ValReprInfo(_,detupArgsL,_)) ->
@@ -2614,20 +2613,20 @@ and OptimizeApplication cenv env (f0,f0ty,tyargs,args,m) =
             | _ -> args |> List.map (fun arg -> UnknownValue,arg)     
         | _ -> args |> List.map (fun arg -> UnknownValue,arg) 
 
-    let args',arginfos = OptimizeExprsThenReshapeAndConsiderSplits cenv env shapes
+    let newArgs,arginfos = OptimizeExprsThenReshapeAndConsiderSplits cenv env shapes
     // beta reducing
-    let expr' = MakeApplicationAndBetaReduce cenv.g (f0',f0ty, [tyargs],args',m) 
+    let newExpr = MakeApplicationAndBetaReduce cenv.g (newf0,f0ty, [tyargs],newArgs,m) 
     
-    match f0', expr' with 
+    match newf0, newExpr with 
     | (Expr.Lambda _ | Expr.TyLambda _), Expr.Let _ -> 
        // we beta-reduced, hence reoptimize 
-        OptimizeExpr cenv env expr'
+        OptimizeExpr cenv env newExpr
     | _ -> 
         // regular
 
         // Determine if this application is a critical tailcall
         let mayBeCriticalTailcall = 
-            match f0' with 
+            match newf0 with 
             | KnownValApp(vref,_typeArgs,otherArgs)   ->
 
                  // Check if this is a call to a function of known arity that has been inferred to not be a critical tailcall when used as a direct call
@@ -2638,7 +2637,7 @@ and OptimizeApplication cenv env (f0,f0ty,tyargs,args,m) =
                      (let valInfoForVal = GetInfoForVal cenv env m vref  in valInfoForVal.ValMakesNoCriticalTailcalls) ||
                      (match env.functionVal with | None -> false | Some (v,_) -> valEq vref.Deref v)
                  if doesNotMakeCriticalTailcall then
-                    let numArgs = otherArgs.Length + args'.Length
+                    let numArgs = otherArgs.Length + newArgs.Length
                     match vref.ValReprInfo with 
                     | Some i -> numArgs > i.NumCurriedArgs 
                     | None -> 
@@ -2652,11 +2651,11 @@ and OptimizeApplication cenv env (f0,f0ty,tyargs,args,m) =
                 // All indirect calls (calls to unknown functions) are assumed to be critical tailcalls 
                 true
 
-        expr', { TotalSize=finfo.TotalSize + AddTotalSizes arginfos
-                 FunctionSize=finfo.FunctionSize + AddFunctionSizes arginfos
-                 HasEffect=true
-                 MightMakeCriticalTailcall = mayBeCriticalTailcall
-                 Info=ValueOfExpr expr' }
+        newExpr, { TotalSize=finfo.TotalSize + AddTotalSizes arginfos
+                   FunctionSize=finfo.FunctionSize + AddFunctionSizes arginfos
+                   HasEffect=true
+                   MightMakeCriticalTailcall = mayBeCriticalTailcall
+                   Info=ValueOfExpr newExpr }
 
 //-------------------------------------------------------------------------
 // Optimize/analyze a lambda expression