[project @ 1997-01-17 00:32:23 by simonpj]

[ghc-hetmet.git] / ghc / compiler / rename / RnIfaces.lhs

diff --git a/ghc/compiler/rename/RnIfaces.lhs b/ghc/compiler/rename/RnIfaces.lhs
index 2a36802..b6f4521 100644 (file)
--- a/ghc/compiler/rename/RnIfaces.lhs
+++ b/ghc/compiler/rename/RnIfaces.lhs
@@ -287,8 +287,13 @@ getWiredInDecl :: Name -> RnMG AvailInfo
 getWiredInDecl name
   =    -- Force in the home module in case it has instance decls for
        -- the thing we are interested in
-    (if mod == gHC__ then
-       returnRn ()                     -- Mini hack; GHC is guaranteed not to have
+    (if not is_tycon || mod == gHC__ then
+       returnRn ()                     -- Mini hack 1: no point for non-tycons; and if we
+                                       -- do this we find PrelNum trying to import PackedString,
+                                       -- because PrelBase's .hi file mentions PackedString.unpackString
+                                       -- But PackedString.hi isn't built by that point!
+                                       --
+                                       -- Mini hack 2; GHC is guaranteed not to have
                                        -- instance decls, so it's a waste of time
                                        -- to read it
     else
@@ -296,7 +301,7 @@ getWiredInDecl name
        returnRn ()
     )                                          `thenRn_`
 
-    if (maybeToBool maybe_wired_in_tycon) then
+    if is_tycon then
        get_wired_tycon the_tycon
     else                               -- Must be a wired-in-Id
     if (isDataCon the_id) then         -- ... a wired-in data constructor
@@ -307,6 +312,7 @@ getWiredInDecl name
     doc_str = ppSep [ppStr "Need home module for wired in thing", ppr PprDebug name]
     (mod,_) = modAndOcc name
     maybe_wired_in_tycon = maybeWiredInTyConName name
+    is_tycon            = maybeToBool maybe_wired_in_tycon
     maybe_wired_in_id    = maybeWiredInIdName    name
     Just the_tycon      = maybe_wired_in_tycon
     Just the_id         = maybe_wired_in_id