--- a/widget/cocoa/nsClipboard.mm
+++ b/widget/cocoa/nsClipboard.mm
@@ -1,15 +1,17 @@
 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "prlog.h"
 
+#include "mozilla/unused.h"
+
 #include "gfxPlatform.h"
 #include "nsCOMPtr.h"
 #include "nsClipboard.h"
 #include "nsString.h"
 #include "nsISupportsPrimitives.h"
 #include "nsXPIDLString.h"
 #include "nsPrimitiveHelpers.h"
 #include "nsMemory.h"
@@ -43,27 +45,28 @@ nsClipboard::nsClipboard() : nsBaseClipb
   EnsureLogInitialized();
 }
 
 nsClipboard::~nsClipboard()
 {
 }
 
 // We separate this into its own function because after an @try, all local
-// variables within that function get marked as volatile, and our C++ type 
+// variables within that function get marked as volatile, and our C++ type
 // system doesn't like volatile things.
-static NSData* 
+static NSData*
 GetDataFromPasteboard(NSPasteboard* aPasteboard, NSString* aType)
 {
   NSData *data = nil;
   @try {
     data = [aPasteboard dataForType:aType];
   } @catch (NSException* e) {
-    NS_WARNING(nsPrintfCString("Exception raised while getting data from the pasteboard: \"%s - %s\"", 
+    NS_WARNING(nsPrintfCString("Exception raised while getting data from the pasteboard: \"%s - %s\"",
                                [[e name] UTF8String], [[e reason] UTF8String]).get());
+    mozilla::unused << e;
   }
   return data;
 }
 
 NS_IMETHODIMP
 nsClipboard::SetNativeClipboardData(int32_t aWhichClipboard)
 {
   NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;