diff --git a/llvm/include/llvm/Support/VirtualFileSystem.h b/llvm/include/llvm/Support/VirtualFileSystem.h
index b718dbaf31895..d7abd1ff85521 100644
--- a/llvm/include/llvm/Support/VirtualFileSystem.h
+++ b/llvm/include/llvm/Support/VirtualFileSystem.h
@@ -678,6 +678,7 @@ class RedirectingFileSystem : public vfs::FileSystem {
       case EK_Directory:
         return false;
       }
+      llvm_unreachable("invalid entry kind");
     }
   };