From 032d7d78ca845983c334471a0583c0bf8165c3bf Mon Sep 17 00:00:00 2001
From: Jose Lorenzo Rodriguez <jose.zap@gmail.com>
Date: Thu, 20 Jun 2019 15:46:22 +0200
Subject: [PATCH 1/2] Fix a memory leak found by mpickering

---
 hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs b/hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs
index aa80778d2..6f7dad940 100644
--- a/hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs
+++ b/hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE BangPatterns #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE FlexibleContexts #-}
@@ -53,7 +54,8 @@ import           Haskell.Ide.Engine.PluginsIdeMonads
 modifyCache :: (HasGhcModuleCache m) => (GhcModuleCache -> GhcModuleCache) -> m ()
 modifyCache f = do
   mc <- getModuleCache
-  setModuleCache (f mc)
+  let !cached = f mc -- Avoid a space leak by forcing the cache calculation
+  setModuleCache cached
 
 -- ---------------------------------------------------------------------
 -- | Runs an IdeM action with the given Cradle

From b7fb445fa51154dcaac715094586cb1bdbe9e0ed Mon Sep 17 00:00:00 2001
From: Jose Lorenzo Rodriguez <jose.zap@gmail.com>
Date: Fri, 21 Jun 2019 09:50:55 +0200
Subject: [PATCH 2/2] Making setCache strict in it's first argument instead

---
 hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs      | 4 +---
 hie-plugin-api/Haskell/Ide/Engine/PluginsIdeMonads.hs | 3 ++-
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs b/hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs
index 6f7dad940..aa80778d2 100644
--- a/hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs
+++ b/hie-plugin-api/Haskell/Ide/Engine/ModuleCache.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE BangPatterns #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE FlexibleContexts #-}
@@ -54,8 +53,7 @@ import           Haskell.Ide.Engine.PluginsIdeMonads
 modifyCache :: (HasGhcModuleCache m) => (GhcModuleCache -> GhcModuleCache) -> m ()
 modifyCache f = do
   mc <- getModuleCache
-  let !cached = f mc -- Avoid a space leak by forcing the cache calculation
-  setModuleCache cached
+  setModuleCache (f mc)
 
 -- ---------------------------------------------------------------------
 -- | Runs an IdeM action with the given Cradle
diff --git a/hie-plugin-api/Haskell/Ide/Engine/PluginsIdeMonads.hs b/hie-plugin-api/Haskell/Ide/Engine/PluginsIdeMonads.hs
index 468d9cbce..06bf7b7eb 100644
--- a/hie-plugin-api/Haskell/Ide/Engine/PluginsIdeMonads.hs
+++ b/hie-plugin-api/Haskell/Ide/Engine/PluginsIdeMonads.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE BangPatterns #-}
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE DeriveFunctor #-}
 {-# LANGUAGE DeriveAnyClass #-}
@@ -499,7 +500,7 @@ instance HasGhcModuleCache IdeM where
     tvar <- lift ask
     state <- liftIO $ readTVarIO tvar
     return (moduleCache state)
-  setModuleCache mc = do
+  setModuleCache !mc = do
     tvar <- lift ask
     liftIO $ atomically $ modifyTVar' tvar (\st -> st { moduleCache = mc })