[C++11] Add 'override' keyword to virtual methods that override their base class.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202953 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/IPO/ExtractGV.cpp

@@ -68,7 +68,7 @@ namespace {
     explicit GVExtractorPass(std::vector<GlobalValue*>& GVs, bool deleteS = true)
       : ModulePass(ID), Named(GVs.begin(), GVs.end()), deleteStuff(deleteS) {}
 
-    bool runOnModule(Module &M) {
+    bool runOnModule(Module &M) override {
       // Visit the global inline asm.
       if (!deleteStuff)
         M.setModuleInlineAsm("");