Use tcRnImports rather than rnImports with GHCi "import" statement: fixes #4832

[ghc-hetmet.git] / compiler / main / HscMain.lhs

diff --git a/compiler/main/HscMain.lhs b/compiler/main/HscMain.lhs
index 09db7a8..09f5130 100644 (file)
--- a/compiler/main/HscMain.lhs
+++ b/compiler/main/HscMain.lhs
@@ -97,7 +97,6 @@ import SrcLoc
 import TcRnDriver
 import TcIface         ( typecheckIface )
 import TcRnMonad
 import TcRnDriver
 import TcIface         ( typecheckIface )
 import TcRnMonad

-import RnNames          ( rnImports )

 import IfaceEnv                ( initNameCache )
 import LoadIface       ( ifaceStats, initExternalPackageState )
 import PrelInfo                ( wiredInThings, basicKnownKeyNames )
 import IfaceEnv                ( initNameCache )
 import LoadIface       ( ifaceStats, initExternalPackageState )
 import PrelInfo                ( wiredInThings, basicKnownKeyNames )

@@ -306,11 +305,12 @@ hscRnImportDecls
         -> [LImportDecl RdrName]
         -> IO GlobalRdrEnv
 
         -> [LImportDecl RdrName]
         -> IO GlobalRdrEnv
 

-hscRnImportDecls hsc_env this_mod import_decls = runHsc hsc_env $ do
-  (_, r, _, _) <- 
-       ioMsgMaybe $ initTc hsc_env HsSrcFile False this_mod $
-          rnImports import_decls
-  return r
+-- It is important that we use tcRnImports instead of calling rnImports directly
+-- because tcRnImports will force-load any orphan modules necessary, making extra
+-- instances/family instances visible (GHC #4832)
+hscRnImportDecls hsc_env this_mod import_decls
+  = runHsc hsc_env $ ioMsgMaybe $ initTc hsc_env HsSrcFile False this_mod $
+          fmap tcg_rdr_env $ tcRnImports hsc_env this_mod import_decls

 
 -- -----------------------------------------------------------------------------
 -- | parse a file, returning the abstract syntax
 
 -- -----------------------------------------------------------------------------
 -- | parse a file, returning the abstract syntax