[project @ 2004-02-25 13:54:30 by simonpj]

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

diff --git a/ghc/compiler/typecheck/TcType.lhs b/ghc/compiler/typecheck/TcType.lhs
index 43e8cd2..753ad4f 100644 (file)
--- a/ghc/compiler/typecheck/TcType.lhs
+++ b/ghc/compiler/typecheck/TcType.lhs
@@ -73,6 +73,7 @@ module TcType (
   isFFILabelTy,        -- :: Type -> Bool
   isFFIDotnetTy,       -- :: DynFlags -> Type -> Bool
   isFFIDotnetObjTy,    -- :: Type -> Bool
+  isFFITy,            -- :: Type -> Bool
   
   toDNType,            -- :: Type -> DNType
 
@@ -770,6 +771,10 @@ restricted set of types as arguments and results (the restricting factor
 being the )
 
 \begin{code}
+isFFITy :: Type -> Bool
+-- True for any TyCon that can possibly be an arg or result of an FFI call
+isFFITy ty = checkRepTyCon legalFFITyCon ty
+
 isFFIArgumentTy :: DynFlags -> Safety -> Type -> Bool
 -- Checks for valid argument type for a 'foreign import'
 isFFIArgumentTy dflags safety ty 
@@ -909,6 +914,11 @@ legalOutgoingTyCon dflags safety tc
   | otherwise
   = marshalableTyCon dflags tc
 
+legalFFITyCon :: TyCon -> Bool
+-- True for any TyCon that can possibly be an arg or result of an FFI call
+legalFFITyCon tc
+  = isUnLiftedTyCon tc || boxedMarshalableTyCon tc || tc == unitTyCon
+
 marshalableTyCon dflags tc
   =  (dopt Opt_GlasgowExts dflags && isUnLiftedTyCon tc)
   || boxedMarshalableTyCon tc