A virtual destructor for the class with virtual methods!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137400 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/LexicalScopes.h

@@ -44,7 +44,7 @@ typedef std::pair<const MachineInstr *, const MachineInstr *> InsnRange;
 class LexicalScopes {
 public:
   LexicalScopes() : MF(NULL),  CurrentFnLexicalScope(NULL) { }
-  ~LexicalScopes();
+  virtual ~LexicalScopes();
 
   /// initialize - Scan machine function and constuct lexical scope nest.
   virtual void initialize(const MachineFunction &);