From: Simon Marlow <simonmar@microsoft.com>
Date: Wed, 26 Sep 2007 10:07:32 +0000 (+0000)
Subject: fix #1734, panic in :show modules after load failure
X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=commitdiff_plain;h=cf2ee54939510b1a64ad99ca7d00aeb8a862c06b

fix #1734, panic in :show modules after load failure
---

diff --git a/compiler/ghci/InteractiveUI.hs b/compiler/ghci/InteractiveUI.hs
index 7c64941..4d3d08d 100644
--- a/compiler/ghci/InteractiveUI.hs
+++ b/compiler/ghci/InteractiveUI.hs
@@ -933,10 +933,9 @@ doLoad session howmuch = do
 afterLoad ok session = do
   io (revertCAFs)  -- always revert CAFs on load.
   discardTickArrays
-  graph <- io (GHC.getModuleGraph session)
-  graph' <- filterM (io . GHC.isLoaded session . GHC.ms_mod_name) graph
-  setContextAfterLoad session graph'
-  modulesLoadedMsg ok (map GHC.ms_mod_name graph')
+  loaded_mods <- getLoadedModules session
+  setContextAfterLoad session loaded_mods
+  modulesLoadedMsg ok (map GHC.ms_mod_name loaded_mods)
 
 setContextAfterLoad session [] = do
   prel_mod <- getPrelude
@@ -1287,10 +1286,15 @@ showCmd str = do
 
 showModules = do
   session <- getSession
-  let show_one ms = do m <- io (GHC.showModule session ms)
-		       io (putStrLn m)
+  loaded_mods <- getLoadedModules session
+        -- we want *loaded* modules only, see #1734
+  let show_one ms = do m <- io (GHC.showModule session ms); io (putStrLn m)
+  mapM_ show_one loaded_mods
+
+getLoadedModules :: GHC.Session -> GHCi [GHC.ModSummary]
+getLoadedModules session = do
   graph <- io (GHC.getModuleGraph session)
-  mapM_ show_one graph
+  filterM (io . GHC.isLoaded session . GHC.ms_mod_name) graph
 
 showBindings = do
   s <- getSession