From 0fc35d72840ca5ca1ce7de00437e4aab258f6a09 Mon Sep 17 00:00:00 2001
From: Daniel Dunbar <daniel@zuster.org>
Date: Tue, 17 Aug 2010 22:32:34 +0000
Subject: [PATCH] CrashRecovery: Make CrashRecoveryContext static methods
 thread safe.

llvm-svn: 111307
---
 include/llvm/Support/CrashRecoveryContext.h |  6 ++----
 lib/Support/CrashRecoveryContext.cpp        | 10 ++++++++++
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/include/llvm/Support/CrashRecoveryContext.h b/include/llvm/Support/CrashRecoveryContext.h
index d44d24ac95e..45a43fa1950 100644
--- a/include/llvm/Support/CrashRecoveryContext.h
+++ b/include/llvm/Support/CrashRecoveryContext.h
@@ -47,12 +47,10 @@ public:
   CrashRecoveryContext() : Impl(0) {}
   ~CrashRecoveryContext();
 
-  /// \brief Enable crash recovery. This function is not thread safe, clients
-  /// should call it during startup or with a lock held.
+  /// \brief Enable crash recovery.
   static void Enable();
 
-  /// \brief Disable crash recovery. This function is not thread safe, clients
-  /// should call it during startup or with a lock held.
+  /// \brief Disable crash recovery.
   static void Disable();
 
   /// \brief Execute the provide callback function (with the given arguments) in
diff --git a/lib/Support/CrashRecoveryContext.cpp b/lib/Support/CrashRecoveryContext.cpp
index de981325394..d1ecbb74dac 100644
--- a/lib/Support/CrashRecoveryContext.cpp
+++ b/lib/Support/CrashRecoveryContext.cpp
@@ -10,6 +10,7 @@
 #include "llvm/Support/CrashRecoveryContext.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Config/config.h"
+#include "llvm/System/Mutex.h"
 #include "llvm/System/ThreadLocal.h"
 #include <setjmp.h>
 #include <cstdio>
@@ -47,6 +48,7 @@ public:
 
 }
 
+static sys::Mutex gCrashRecoveryContexMutex;
 static bool gCrashRecoveryEnabled = false;
 
 CrashRecoveryContext::~CrashRecoveryContext() {
@@ -59,6 +61,8 @@ CrashRecoveryContext::~CrashRecoveryContext() {
 // FIXME: No real Win32 implementation currently.
 
 void CrashRecoveryContext::Enable() {
+  sys::ScopedLock L(gCrashRecoveryContexMutex);
+
   if (gCrashRecoveryEnabled)
     return;
 
@@ -66,6 +70,8 @@ void CrashRecoveryContext::Enable() {
 }
 
 void CrashRecoveryContext::Disable() {
+  sys::ScopedLock L(gCrashRecoveryContexMutex);
+
   if (!gCrashRecoveryEnabled)
     return;
 
@@ -121,6 +127,8 @@ static void CrashRecoverySignalHandler(int Signal) {
 }
 
 void CrashRecoveryContext::Enable() {
+  sys::ScopedLock L(gCrashRecoveryContexMutex);
+
   if (gCrashRecoveryEnabled)
     return;
 
@@ -138,6 +146,8 @@ void CrashRecoveryContext::Enable() {
 }
 
 void CrashRecoveryContext::Disable() {
+  sys::ScopedLock L(gCrashRecoveryContexMutex);
+
   if (!gCrashRecoveryEnabled)
     return;