diff --git a/lib/Analysis/CFG.cpp b/lib/Analysis/CFG.cpp
index 2818cf6..18bbbb1 100644
--- a/lib/Analysis/CFG.cpp
+++ b/lib/Analysis/CFG.cpp
@@ -2774,6 +2774,7 @@
 
 const CXXDestructorDecl *CFGImplicitDtor::getDestructorDecl() const {
   switch (getKind()) {
+    default: assert(0 && "Unknown CFGElement");
     case CFGElement::Invalid:
     case CFGElement::Statement:
     case CFGElement::Initializer: