Appease -Wnon-virtual-dtor

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143965 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaPseudoObject.cpp b/lib/Sema/SemaPseudoObject.cpp
index 4dc6a18..b8497e5 100644
--- a/lib/Sema/SemaPseudoObject.cpp
+++ b/lib/Sema/SemaPseudoObject.cpp
@@ -141,6 +141,8 @@
       : S(S), ResultIndex(PseudoObjectExpr::NoResult),
         GenericLoc(genericLoc) {}
 
+    virtual ~PseudoOpBuilder() {}
+
     /// Add a normal semantic expression.
     void addSemanticExpr(Expr *semantic) {
       Semantics.push_back(semantic);