From dbbd409b15bce1d29e6bb188f334efdbc6684d91 Mon Sep 17 00:00:00 2001
From: Ben Langmuir <blangmuir@apple.com>
Date: Sun, 4 May 2014 05:20:54 +0000
Subject: [PATCH] Fix a use-after-free bug I recently introduced in
 lookupModuleFile

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@207932 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Serialization/ModuleManager.cpp | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/lib/Serialization/ModuleManager.cpp b/lib/Serialization/ModuleManager.cpp
index 9b3159e170..66f18158a6 100644
--- a/lib/Serialization/ModuleManager.cpp
+++ b/lib/Serialization/ModuleManager.cpp
@@ -390,11 +390,10 @@ bool ModuleManager::lookupModuleFile(StringRef FileName,
   }
 
   if ((ExpectedSize && ExpectedSize != File->getSize()) ||
-      (ExpectedModTime && ExpectedModTime != File->getModificationTime())) {
-    FileMgr.invalidateCache(File);
-    File = nullptr;
+      (ExpectedModTime && ExpectedModTime != File->getModificationTime()))
+    // Do not destroy File, as it may be referenced. If we need to rebuild it,
+    // it will be destroyed by removeModules.
     return true;
-  }
 
   return false;
 }
-- 
2.40.0