diff --git a/clang/lib/Basic/Sanitizers.cpp b/clang/lib/Basic/Sanitizers.cpp
--- a/clang/lib/Basic/Sanitizers.cpp
+++ b/clang/lib/Basic/Sanitizers.cpp
@@ -68,6 +68,8 @@
   case llvm::AsanDtorKind::Global:
     return "global";
   case llvm::AsanDtorKind::Invalid:
+    LLVM_FALLTHROUGH;
+  default:
     return "invalid";
   }
 }