diff --git a/src/wasm-builder.h b/src/wasm-builder.h
index 0c3cec5c2b6..4b5df766d0c 100644
--- a/src/wasm-builder.h
+++ b/src/wasm-builder.h
@@ -1338,11 +1338,14 @@ class Builder {
       block = any->dynCast<Block>();
     }
     if (!block || block->name.is()) {
-      block = makeBlock(any);
+      block = makeBlock(name, any);
+    } else {
+      block->name = name;
     }
-    block->name = name;
     if (append) {
       block->list.push_back(append);
+    }
+    if (append || type) {
       block->finalize(type);
     }
     return block;