Make InstalledUnitId be ONLY a FastString.

It turns out that we don't really need to be able to
extract a ComponentId from UnitId, except in one case.
So compress UnitId into a single FastString.

The one case where we do need the ComponentId is when
we are compiling an instantiated version of a package;
we need the ComponentId to look up the indefinite
version of this package from the database.  So now we
just pass it in as an argument -this-component-id.

Also: ghc-pkg now no longer will unregister a package if
you register one with the same package name, if the
instantiations don't match.

Cabal submodule update which tracks the same data type
change.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

1 files changed, 4 insertions, 3 deletions

diff --git a/compiler/iface/LoadIface.hs b/compiler/iface/LoadIface.hs
index ca11c6f59b..6005ba5053 100644
--- a/compiler/iface/LoadIface.hs
+++ b/compiler/iface/LoadIface.hs
@@ -533,12 +533,12 @@ computeInterface doc_str hi_boot_file mod0 = do
     MASSERT( not (isHoleModule mod0) )
     dflags <- getDynFlags
     case splitModuleInsts mod0 of
-        (imod, Just insts) | not (unitIdIsDefinite (thisPackage dflags)) -> do
+        (imod, Just indef) | not (unitIdIsDefinite (thisPackage dflags)) -> do
             r <- findAndReadIface doc_str imod hi_boot_file
             case r of
                 Succeeded (iface0, path) -> do
                     hsc_env <- getTopEnv
-                    r <- liftIO (rnModIface hsc_env insts Nothing iface0)
+                    r <- liftIO (rnModIface hsc_env (indefUnitIdInsts (indefModuleUnitId indef)) Nothing iface0)
                     return (Succeeded (r, path))
                 Failed err -> return (Failed err)
         (mod, _) ->
@@ -560,7 +560,8 @@ moduleFreeHolesPrecise doc_str mod
  | moduleIsDefinite mod = return (Succeeded emptyUniqDSet)
  | otherwise =
    case splitModuleInsts mod of
-    (imod, Just insts) -> do
+    (imod, Just indef) -> do
+        let insts = indefUnitIdInsts (indefModuleUnitId indef)
         traceIf (text "Considering whether to load" <+> ppr mod <+>
                  text "to compute precise free module holes")
         (eps, hpt) <- getEpsAndHpt