partial fix for #1119

[ghc-hetmet.git] / compiler / iface / LoadIface.lhs

diff --git a/compiler/iface/LoadIface.lhs b/compiler/iface/LoadIface.lhs
index cfb8f12..6b2660d 100644 (file)
--- a/compiler/iface/LoadIface.lhs
+++ b/compiler/iface/LoadIface.lhs
@@ -51,6 +51,7 @@ import Outputable
 import BinIface
 import Panic
 
+import Control.Monad (when)
 import Data.List
 import Data.Maybe
 import Data.IORef
@@ -175,9 +176,9 @@ loadInterface doc_str mod from
                        -- The (src_imp == mi_boot iface) test checks that the already-loaded
                        -- interface isn't a boot iface.  This can conceivably happen,
                        -- if an earlier import had a before we got to real imports.   I think.
-           other -> do
+           other -> do {
 
-       { let { hi_boot_file = case from of
+          let { hi_boot_file = case from of
                                ImportByUser usr_boot -> usr_boot
                                ImportBySystem        -> sys_boot
 
@@ -412,18 +413,25 @@ findAndReadIface doc_str mod hi_boot_file
 
        -- Look for the file
        ; hsc_env <- getTopEnv
-       ; mb_found <- ioToIOEnv (findHiFile hsc_env mod hi_boot_file)
+       ; mb_found <- ioToIOEnv (findExactModule hsc_env mod)
        ; case mb_found of {
-             Failed err -> do
+              
+             err | notFound err -> do
                { traceIf (ptext SLIT("...not found"))
                ; dflags <- getDOpts
                ; returnM (Failed (cannotFindInterface dflags 
                                        (moduleName mod) err)) } ;
-
-             Succeeded file_path -> do 
+             Found loc mod -> do 
 
        -- Found file, so read it
-       { traceIf (ptext SLIT("readIFace") <+> text file_path)
+       { let { file_path = addBootSuffix_maybe hi_boot_file (ml_hi_file loc) }
+
+        ; if thisPackage dflags == modulePackageId mod
+                && not (isOneShot (ghcMode dflags))
+            then returnM (Failed (homeModError mod loc))
+            else do {
+
+        ; traceIf (ptext SLIT("readIFace") <+> text file_path)
        ; read_result <- readIface mod file_path hi_boot_file
        ; case read_result of
            Failed err -> returnM (Failed (badIfaceFile file_path err))
@@ -433,18 +441,10 @@ findAndReadIface doc_str mod hi_boot_file
                | otherwise ->
                  returnM (Succeeded (iface, file_path))
                        -- Don't forget to fill in the package name...
-       }}}
-
-findHiFile :: HscEnv -> Module -> IsBootInterface
-          -> IO (MaybeErr FindResult FilePath)
-findHiFile hsc_env mod hi_boot_file
-  = do
-      maybe_found <- findExactModule hsc_env mod
-      case maybe_found of
-       Found loc mod -> return (Succeeded path)
-               where
-                  path = addBootSuffix_maybe hi_boot_file (ml_hi_file loc)
-       err -> return (Failed err)
+       }}}}
+
+notFound (Found _ _) = False
+notFound _ = True
 \end{code}
 
 @readIface@ tries just the one file.
@@ -689,5 +689,12 @@ wrongIfaceModErr iface mod_name file_path
            ]
        ]
   where iface_file = doubleQuotes (text file_path)
+
+homeModError mod location
+  = ptext SLIT("attempting to use module ") <> quotes (ppr mod)
+    <> (case ml_hs_file location of
+           Just file -> space <> parens (text file)
+           Nothing   -> empty)
+    <+> ptext SLIT("which is not loaded")
 \end{code}