From: Matthijs Kooijman <m.kooijman@student.utwente.nl>
Date: Thu, 6 Aug 2009 17:19:52 +0000 (+0200)
Subject: Filter out empty-typed binders in selector cases.
X-Git-Url: https://git.stderr.nl/gitweb?p=matthijs%2Fmaster-project%2Fc%CE%BBash.git;a=commitdiff_plain;h=d947c778e6e6e95e896cfc6926a4fdf12f16806d

Filter out empty-typed binders in selector cases.

This makes sure that the non-empty binders are skipped when calculating
the field number, which prevents overflow when indexing the field names.
---

diff --git "a/c\316\273ash/CLasH/VHDL/Generate.hs" "b/c\316\273ash/CLasH/VHDL/Generate.hs"
index 827315c..5386e7e 100644
--- "a/c\316\273ash/CLasH/VHDL/Generate.hs"
+++ "b/c\316\273ash/CLasH/VHDL/Generate.hs"
@@ -166,7 +166,8 @@ mkConcSm (bndr, expr@(CoreSyn.Case (CoreSyn.Var scrut) b ty [alt]))
                 | otherwise =
   case alt of
     (CoreSyn.DataAlt dc, bndrs, (CoreSyn.Var sel_bndr)) -> do
-      case List.elemIndex sel_bndr bndrs of
+      bndrs' <- Monad.filterM hasNonEmptyType bndrs
+      case List.elemIndex sel_bndr bndrs' of
         Just i -> do
           labels <- MonadState.lift tsType $ getFieldLabels (Id.idType scrut)
           let label = labels!!i