Index: lib/IR/Metadata.cpp
===================================================================
--- lib/IR/Metadata.cpp
+++ lib/IR/Metadata.cpp
@@ -301,7 +301,8 @@
   auto &Context = V->getContext();
   auto *&Entry = Context.pImpl->ValuesAsMetadata[V];
   if (!Entry) {
-    assert((isa<Constant>(V) || isa<Argument>(V) || isa<Instruction>(V)) &&
+    assert((isa<Constant>(V) || isa<Argument>(V) || isa<Instruction>(V) ||
+            isa<BasicBlock>(V)) &&
            "Expected constant or function-local value");
     assert(!V->IsUsedByMD &&
            "Expected this to be the only metadata use");