Switch assert(0/false) llvm_unreachable.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@140367 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 48f2f96..34eb498 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -3205,7 +3205,7 @@
 
   switch (Attr.getKind()) {
     default:
-      assert(0 && "invalid ownership attribute");
+      llvm_unreachable("invalid ownership attribute");
       return;
     case AttributeList::AT_ns_returns_autoreleased:
       D->addAttr(::new (S.Context) NSReturnsAutoreleasedAttr(Attr.getRange(),