From ce2d8254c2130bd61fceffaeae57caea51b9e24a Mon Sep 17 00:00:00 2001
From: Shao Cheng <astrohavoc@gmail.com>
Date: Tue, 3 Apr 2018 00:40:44 +0800
Subject: [PATCH] Previous TTG approach of IR is a failure. Prep for a lower
 tech version that works

---
 asterius/src/Asterius/IR.hs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/asterius/src/Asterius/IR.hs b/asterius/src/Asterius/IR.hs
index e640db1d..2374a825 100644
--- a/asterius/src/Asterius/IR.hs
+++ b/asterius/src/Asterius/IR.hs
@@ -250,9 +250,11 @@ marshalCmmBranch mod_sym func_sym exit_node =
           , trueDest = encodeLabel mod_sym func_sym cml_true
           , falseDest = encodeLabel mod_sym func_sym cml_false
           }
-    GHC.CmmSwitch _ _ ->
+    GHC.CmmSwitch _ _ -> do
+      MarshalContext {..} <- ask
       pure
-        SwitchBranch {switch = ExpressionStub, defDest = undefined, dests = []}
+        SwitchBranch
+          {switch = ExpressionStub, defDest = unreachableBlock, dests = []}
     GHC.CmmCall {..} -> pure CallBranch {callee = ExpressionStub}
     GHC.CmmForeignCall {} -> pure ForeignCallStub