--- content/media/MediaEngineDefault.cpp~
+++ content/media/MediaEngineDefault.cpp
@@ -232,12 +232,12 @@ nsresult
 MediaEngineDefaultAudioSource::Start(SourceMediaStream* aStream, TrackID aID)
 {
   if (mState != kAllocated) {
-    return NULL;
+    return 0;
   }
 
   mTimer = do_CreateInstance(NS_TIMER_CONTRACTID);
   if (!mTimer) {
-    return NULL;
+    return 0;
   }
 
   mSource = aStream;
--- gfx/layers/opengl/ImageLayerOGL.cpp~
+++ gfx/layers/opengl/ImageLayerOGL.cpp
@@ -936,7 +936,7 @@ ShadowImageLayerOGL::CleanupResources()
 {
   if (mSharedHandle) {
     gl()->ReleaseSharedHandle(mShareType, mSharedHandle);
-    mSharedHandle = NULL;
+    mSharedHandle = 0;
   }
 
   mYUVTexture[0].Release();
--- intl/locale/src/unix/nsDateTimeFormatUnix.cpp~
+++ intl/locale/src/unix/nsDateTimeFormatUnix.cpp
@@ -100,7 +100,7 @@ void nsDateTimeFormatUnix::LocalePreferr
   struct tm *tmc;
   int i;
 
-  tt = time((time_t)NULL);
+  tt = time(NULL);
   tmc = localtime(&tt);
 
   tmc->tm_hour=22;    // put the test sample hour to 22:00 which is 10PM
--- ipc/glue/CrossProcessMutex_unimplemented.cpp~
+++ ipc/glue/CrossProcessMutex_unimplemented.cpp
@@ -40,7 +40,7 @@ CrossProcessMutexHandle
 CrossProcessMutex::ShareToProcess(base::ProcessHandle aHandle)
 {
   NS_RUNTIMEABORT("Cross-process mutices not allowed on this platform - woah! We should've aborted by now!");
-  return NULL;
+  return 0;
 }
 
 }