[project @ 1996-01-18 16:33:17 by partain]

[ghc-hetmet.git] / ghc / compiler / typecheck / Unify.lhs

diff --git a/ghc/compiler/typecheck/Unify.lhs b/ghc/compiler/typecheck/Unify.lhs
index cd218cb..e97f59d 100644 (file)
--- a/ghc/compiler/typecheck/Unify.lhs
+++ b/ghc/compiler/typecheck/Unify.lhs
@@ -19,6 +19,7 @@ import AbsSyn
 import TcMonad
 
 import CmdLineOpts     ( GlobalSwitch(..) )
+import CoreLift                ( isUnboxedButNotState )
 import Errors          ( unifyErr, UnifyErrInfo(..), UnifyErrContext  )
 import Id              ( Id, DataCon(..), Inst )
 import Maybes          ( Maybe(..) )
@@ -350,11 +351,11 @@ uVar tv1 ps_ty2 ty2 err_ctxt
     tyvar1 `bindTo` ty2 
        = extendSubstTc tyvar1 ty2 err_ctxt
 
-    tyvar1 `bindToUnboxed` ty2
+    tyvar1 `bindToUnboxed` ty2 
        = getSwitchCheckerTc    `thenNF_Tc` \ sw_chkr ->
-         if sw_chkr SpecialiseUnboxed then
+         if sw_chkr SpecialiseUnboxed && isUnboxedButNotState ty2 then
              extendSubstTc tyvar1 ty2 err_ctxt
          else
              getSrcLocTc       `thenNF_Tc` \ src_loc ->
-              failTc (unifyErr (UnifyMisMatch ty1 ps_ty2) err_ctxt src_loc)
+              failTc (unifyErr (UnifyUnboxedMisMatch ty1 ps_ty2) err_ctxt src_loc)
 \end{code}