Store a SrcSpan instead of a SrcLoc inside a Name

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

diff --git a/compiler/typecheck/TcSimplify.lhs b/compiler/typecheck/TcSimplify.lhs
index 911e2ff..b9ff789 100644 (file)
--- a/compiler/typecheck/TcSimplify.lhs
+++ b/compiler/typecheck/TcSimplify.lhs
@@ -889,7 +889,7 @@ makeImplicationBind loc all_tvs reft
  | otherwise                   -- Otherwise we must generate a binding
  = do  { uniq <- newUnique 
        ; span <- getSrcSpanM
-       ; let name = mkInternalName uniq (mkVarOcc "ic") (srcSpanStart span)
+       ; let name = mkInternalName uniq (mkVarOcc "ic") span
              implic_inst = ImplicInst { tci_name = name, tci_reft = reft,
                                         tci_tyvars = all_tvs, 
                                         tci_given = givens,
@@ -2577,7 +2577,7 @@ report_no_instances tidy_env mb_what insts
                                 quotes (pprWithCommas ppr (varSetElems (tyVarsOfInst dict))),
                              ptext SLIT("Use -fallow-incoherent-instances to use the first choice above")])]
       where
-       ispecs = [ispec | (_, ispec) <- matches]
+       ispecs = [ispec | (ispec, _) <- matches]
 
     mk_no_inst_err insts
       | null insts = empty
@@ -2650,6 +2650,10 @@ mkMonomorphismMsg tidy_env inst_tvs
   = findGlobals (mkVarSet inst_tvs) tidy_env   `thenM` \ (tidy_env, docs) ->
     returnM (tidy_env, mk_msg docs)
   where
+    mk_msg _ | any isRuntimeUnk inst_tvs
+        =  vcat [ptext SLIT("Cannot resolve unknown runtime types:") <+>
+                   (pprWithCommas ppr inst_tvs),
+                ptext SLIT("Use :print or :force to determine these types")]
     mk_msg []   = ptext SLIT("Probable fix: add a type signature that fixes these type variable(s)")
                        -- This happens in things like
                        --      f x = show (read "foo")
@@ -2658,6 +2662,11 @@ mkMonomorphismMsg tidy_env inst_tvs
                        nest 2 (vcat docs),
                        monomorphism_fix
                       ]
+
+isRuntimeUnk :: TcTyVar -> Bool
+isRuntimeUnk x | SkolemTv RuntimeUnkSkol <- tcTyVarDetails x = True
+               | otherwise = False
+
 monomorphism_fix :: SDoc
 monomorphism_fix = ptext SLIT("Probable fix:") <+> 
                   (ptext SLIT("give these definition(s) an explicit type signature")