From 29233802236f7fe1db20e00eca4f5cc8f3f64ade Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Wed, 23 Mar 2011 15:13:44 +0000
Subject: [PATCH] Teach DelayedDiagnostic to copy its string, rather than hope
 that the string itself lives longer than the DelayedDiagnostic. Fixes a
 recent use-after-free regression due to my availability attribute work.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@128148 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Sema/DelayedDiagnostic.h | 18 +--------
 lib/Sema/CMakeLists.txt                |  1 +
 lib/Sema/DelayedDiagnostic.cpp         | 51 ++++++++++++++++++++++++++
 lib/Sema/SemaDeclAttr.cpp              |  2 +-
 4 files changed, 55 insertions(+), 17 deletions(-)
 create mode 100644 lib/Sema/DelayedDiagnostic.cpp

diff --git a/include/clang/Sema/DelayedDiagnostic.h b/include/clang/Sema/DelayedDiagnostic.h
index 6e808de9a1..8395138ab6 100644
--- a/include/clang/Sema/DelayedDiagnostic.h
+++ b/include/clang/Sema/DelayedDiagnostic.h
@@ -119,25 +119,11 @@ public:
 
   SourceLocation Loc;
 
-  void destroy() {
-    switch (Kind) {
-    case Access: getAccessData().~AccessedEntity(); break;
-    case Deprecation: break;
-    }
-  }
+  void Destroy();
 
   static DelayedDiagnostic makeDeprecation(SourceLocation Loc,
                                            const NamedDecl *D,
-                                           llvm::StringRef Msg) {
-    DelayedDiagnostic DD;
-    DD.Kind = Deprecation;
-    DD.Triggered = false;
-    DD.Loc = Loc;
-    DD.DeprecationData.Decl = D;
-    DD.DeprecationData.Message = Msg.data();
-    DD.DeprecationData.MessageLen = Msg.size();
-    return DD;
-  }
+                                           llvm::StringRef Msg);
 
   static DelayedDiagnostic makeAccess(SourceLocation Loc,
                                       const AccessedEntity &Entity) {
diff --git a/lib/Sema/CMakeLists.txt b/lib/Sema/CMakeLists.txt
index 0d66e259d4..e1f0cb660b 100644
--- a/lib/Sema/CMakeLists.txt
+++ b/lib/Sema/CMakeLists.txt
@@ -5,6 +5,7 @@ add_clang_library(clangSema
   AttributeList.cpp
   CodeCompleteConsumer.cpp
   DeclSpec.cpp
+  DelayedDiagnostic.cpp
   IdentifierResolver.cpp
   JumpDiagnostics.cpp
   Sema.cpp
diff --git a/lib/Sema/DelayedDiagnostic.cpp b/lib/Sema/DelayedDiagnostic.cpp
new file mode 100644
index 0000000000..af548fe134
--- /dev/null
+++ b/lib/Sema/DelayedDiagnostic.cpp
@@ -0,0 +1,51 @@
+//===--- DelayedDiagnostic.cpp - Delayed declarator diagnostics -*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the DelayedDiagnostic class implementation, which
+// is used to record diagnostics that are being conditionally produced
+// during declarator parsing.
+//
+// This file also defines AccessedEntity.
+//
+//===----------------------------------------------------------------------===//
+#include "clang/Sema/DelayedDiagnostic.h"
+#include <string.h>
+using namespace clang;
+using namespace sema;
+
+DelayedDiagnostic DelayedDiagnostic::makeDeprecation(SourceLocation Loc,
+                                                     const NamedDecl *D,
+                                                     llvm::StringRef Msg) {
+  DelayedDiagnostic DD;
+  DD.Kind = Deprecation;
+  DD.Triggered = false;
+  DD.Loc = Loc;
+  DD.DeprecationData.Decl = D;
+  char *MessageData = 0;
+  if (Msg.size()) {
+    MessageData = new char [Msg.size()];
+    memcpy(MessageData, Msg.data(), Msg.size());
+  }
+
+  DD.DeprecationData.Message = MessageData;
+  DD.DeprecationData.MessageLen = Msg.size();
+  return DD;
+}
+
+void DelayedDiagnostic::Destroy() {
+  switch (Kind) {
+  case Access: 
+    getAccessData().~AccessedEntity(); 
+    break;
+
+  case Deprecation: 
+    delete [] DeprecationData.Message;
+    break;
+  }
+}
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 31523229c5..81bf230f94 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -3095,7 +3095,7 @@ void Sema::DelayedDiagnostics::popParsingDecl(Sema &S, ParsingDeclState state,
 
   // Destroy all the delayed diagnostics we're about to pop off.
   for (unsigned i = state.SavedStackSize, e = DD.StackSize; i != e; ++i)
-    DD.Stack[i].destroy();
+    DD.Stack[i].Destroy();
 
   DD.StackSize = state.SavedStackSize;
 }
-- 
2.40.0