Put full ImportDecls in ModSummary instead of just ModuleNames

... and use it to make ghc -M generate correct cross-package
dependencies when using package-qualified imports (needed for the new
build system).  Since we're already parsing the ImportDecl from the
source file, there seems no good reason not to keep it in the
ModSummary, it might be useful for other things too.

1 files changed, 17 insertions, 15 deletions

diff --git a/compiler/main/DriverMkDepend.hs b/compiler/main/DriverMkDepend.hs
index 5b63392bf3..adfcbbdbf0 100644
--- a/compiler/main/DriverMkDepend.hs
+++ b/compiler/main/DriverMkDepend.hs
@@ -17,6 +17,7 @@ module DriverMkDepend (
 
 import qualified GHC
 import GHC              ( ModSummary(..), GhcMonad )
+import HsSyn            ( ImportDecl(..) )
 import PrelNames
 import DynFlags
 import Util
@@ -186,8 +187,8 @@ processDeps dflags hsc_env excl_mods hdl (AcyclicSCC node)
               obj_file  = msObjFilePath node
               obj_files = insertSuffixes obj_file extra_suffixes
 
-              do_imp is_boot imp_mod
-                = do { mb_hi <- findDependency hsc_env src_file imp_mod
+              do_imp is_boot pkg_qual imp_mod
+                = do { mb_hi <- findDependency hsc_env pkg_qual imp_mod
                                                is_boot include_pkg_deps
                      ; case mb_hi of {
                            Nothing      -> return () ;
@@ -207,29 +208,30 @@ processDeps dflags hsc_env excl_mods hdl (AcyclicSCC node)
 
                 -- Emit a dependency for each import
 
-        -- SOURCE imports
-        ; mapM_ (do_imp True)
-                (filter (`notElem` excl_mods) (map unLoc (ms_srcimps node)))
+        ; let do_imps is_boot idecls = sequence_
+                    [ do_imp is_boot (ideclPkgQual i) mod
+                    | L _ i <- idecls,
+                      let mod = unLoc (ideclName i),
+                      mod `notElem` excl_mods ]
 
-        -- regular imports
-        ; mapM_ (do_imp False)
-                (filter (`notElem` excl_mods) (map unLoc (ms_imps node)))
+        ; do_imps True  (ms_srcimps node)
+        ; do_imps False (ms_imps node)
 
         ; when (dopt Opt_ImplicitPrelude (ms_hspp_opts node)) $
-            do_imp False pRELUDE_NAME
+            do_imp False Nothing pRELUDE_NAME
         }
 
 
 findDependency  :: HscEnv
-                -> FilePath             -- Importing module: used only for error msg
+                -> Maybe FastString     -- package qualifier, if any
                 -> ModuleName           -- Imported module
                 -> IsBootInterface      -- Source import
                 -> Bool                 -- Record dependency on package modules
                 -> IO (Maybe FilePath)  -- Interface file file
-findDependency hsc_env _ imp is_boot include_pkg_deps
+findDependency hsc_env pkg imp is_boot include_pkg_deps
   = do  {       -- Find the module; this will be fast because
                 -- we've done it once during downsweep
-          r <- findImportedModule hsc_env imp Nothing
+          r <- findImportedModule hsc_env imp pkg
         ; case r of
             Found loc _
                 -- Home package: just depend on the .hi or hi-boot file
@@ -359,7 +361,7 @@ pprCycle summaries = pp_group (CyclicSCC summaries)
           pp_ms loop_breaker $$ vcat (map pp_group groups)
         where
           (boot_only, others) = partition is_boot_only mss
-          is_boot_only ms = not (any in_group (ms_imps ms))
+          is_boot_only ms = not (any in_group (map (ideclName.unLoc) (ms_imps ms)))
           in_group (L _ m) = m `elem` group_mods
           group_mods = map (moduleName . ms_mod) mss
 
@@ -368,8 +370,8 @@ pprCycle summaries = pp_group (CyclicSCC summaries)
           groups = GHC.topSortModuleGraph True all_others Nothing
 
     pp_ms summary = text mod_str <> text (take (20 - length mod_str) (repeat ' '))
-                       <+> (pp_imps empty (ms_imps summary) $$
-                            pp_imps (ptext (sLit "{-# SOURCE #-}")) (ms_srcimps summary))
+                       <+> (pp_imps empty (map (ideclName.unLoc) (ms_imps summary)) $$
+                            pp_imps (ptext (sLit "{-# SOURCE #-}")) (map (ideclName.unLoc) (ms_srcimps summary)))
         where
           mod_str = moduleNameString (moduleName (ms_mod summary))