[project @ 2001-12-17 12:32:05 by simonmar]

mkLocalNonRec bug fix: we always want to generate a case when the rhs
of a binding is an unlifted type.  Previously the two cases for an
unlifted rhs and a strict binding were handled together which caused
some confusion, so now the cases are separate.

diff --git a/ghc/compiler/coreSyn/CorePrep.lhs b/ghc/compiler/coreSyn/CorePrep.lhs
index 1948974..da19ebd 100644 (file)
--- a/ghc/compiler/coreSyn/CorePrep.lhs
+++ b/ghc/compiler/coreSyn/CorePrep.lhs
@@ -504,11 +504,17 @@ mkLocalNonRec :: Id  -> RhsDemand                         -- Lhs: id with demand
              -> UniqSM (OrdList FloatingBind)
 
 mkLocalNonRec bndr dem floats rhs
-  |  isUnLiftedType (idType bndr) || isStrict dem 
-       -- It's a strict let, or the binder is unlifted,
-       -- so we definitely float all the bindings
+  | isUnLiftedType (idType bndr)
+       -- If this is an unlifted binding, we always make a case for it.
   = ASSERT( not (isUnboxedTupleType (idType bndr)) )
-    let                -- Don't make a case for a value binding,
+    let
+       float = FloatCase bndr rhs (exprOkForSpeculation rhs)
+    in
+    returnUs (floats `snocOL` float)
+
+  | isStrict dem 
+       -- It's a strict let so we definitely float all the bindings
+ = let         -- Don't make a case for a value binding,
                -- even if it's strict.  Otherwise we get
                --      case (\x -> e) of ...!
        float | exprIsValue rhs = FloatLet (NonRec bndr rhs)