diff --git a/src/Client/QueryFuzzer.cpp b/src/Client/QueryFuzzer.cpp
index bfcfe659982..39ca7a5ed88 100644
--- a/src/Client/QueryFuzzer.cpp
+++ b/src/Client/QueryFuzzer.cpp
@@ -1244,7 +1244,7 @@ void QueryFuzzer::fuzzMain(ASTPtr & ast)
     std::cout << std::endl;
     WriteBufferFromOStream ast_buf(std::cout, 4096);
     formatAST(*ast, ast_buf, false /*highlight*/);
-    ast_buf.next();
+    ast_buf.finalize();
     std::cout << std::endl << std::endl;
 }
 
diff --git a/src/Parsers/MySQL/tests/gtest_create_parser.cpp b/src/Parsers/MySQL/tests/gtest_create_parser.cpp
index 554b3f0a67d..2f65eb6e592 100644
--- a/src/Parsers/MySQL/tests/gtest_create_parser.cpp
+++ b/src/Parsers/MySQL/tests/gtest_create_parser.cpp
@@ -40,5 +40,5 @@ TEST(CreateTableParser, SS)
     ASTPtr ast = parseQuery(p_create_query, input.data(), input.data() + input.size(), "", 0, 0);
     WriteBufferFromOStream buf(std::cerr, 4096);
     ast->dumpTree(buf);
-
+    buf.finalize();
 }