Use MD5 checksums for recompilation checking (fixes #1372, #1959)

[ghc-hetmet.git] / compiler / coreSyn / CoreLint.lhs

diff --git a/compiler/coreSyn/CoreLint.lhs b/compiler/coreSyn/CoreLint.lhs
index f7c63f8..de9830b 100644 (file)
--- a/compiler/coreSyn/CoreLint.lhs
+++ b/compiler/coreSyn/CoreLint.lhs
@@ -363,6 +363,17 @@ lintCoreExpr e@(Case scrut var alt_ty alts) =
   do { scrut_ty <- lintCoreExpr scrut
      ; alt_ty   <- lintTy alt_ty  
      ; var_ty   <- lintTy (idType var) 
   do { scrut_ty <- lintCoreExpr scrut
      ; alt_ty   <- lintTy alt_ty  
      ; var_ty   <- lintTy (idType var) 

+
+     ; let mb_tc_app = splitTyConApp_maybe (idType var)
+     ; case mb_tc_app of 
+         Just (tycon, _)
+              | debugIsOn &&
+                isAlgTyCon tycon && 
+                null (tyConDataCons tycon) -> 
+                  pprTrace "case binder's type has no constructors" (ppr e)
+                      $ return ()
+         _otherwise -> return ()
+

        -- Don't use lintIdBndr on var, because unboxed tuple is legitimate
 
      ; subst <- getTvSubst 
        -- Don't use lintIdBndr on var, because unboxed tuple is legitimate
 
      ; subst <- getTvSubst