You have to provide the following information whenever possible.

**Describe the bug**
This query fails with the latest stable version 21.5.5.12. It worked with the last stable version 21.4.7.3.

**Does it reproduce on recent release?**
yes

**How to reproduce**
21.5.5.12

```
SELECT
    label,
    number
FROM
(
    SELECT
        'a' AS label,
        number
    FROM
    (
        SELECT number
        FROM numbers(10)
    )
    UNION ALL
    SELECT
        'b' AS label,
        number
    FROM
    (
        SELECT number
        FROM numbers(10)
    )
)
WHERE number IN
(
    SELECT number
    FROM numbers(5)
)
```

**Expected behavior**
Query should run without errors

**Error message and/or stacktrace**
```
Received exception from server (version 21.5.5):
Code: 49. DB::Exception: Received from localhost:9000. DB::Exception: Block structure mismatch in Pipe::unitePipes stream: different names of columns:
label String String(size = 0), number UInt64 UInt64(size = 0), 'b' String Const(size = 0, String(size = 1))
label String String(size = 0), number UInt64 UInt64(size = 0), 'a' String Const(size = 0, String(size = 1)).
```

{
    for (auto & node : index)
        node = &materializeNode(*node);
}
const ActionsDAG::Node & ActionsDAG::materializeNode(const Node & node)
{
    FunctionOverloadResolverPtr func_builder_materialize = std::make_unique<FunctionToOverloadResolverAdaptor>(
                            std::make_shared<FunctionMaterialize>());
    const auto & name = node.result_name;
    const auto * func = &addFunction(func_builder_materialize, {&node}, {});
    return addAlias(*func, name);
}
ActionsDAGPtr ActionsDAG::makeConvertingActions(
    const ColumnsWithTypeAndName & source,
    const ColumnsWithTypeAndName & result,
    MatchColumnsMode mode,
    bool ignore_constant_values,
    bool add_casted_columns,
    NameToNameMap * new_names)
{
    size_t num_input_columns = source.size();
    size_t num_result_columns = result.size();
    if (mode == MatchColumnsMode::Position && num_input_columns != num_result_columns)
        throw Exception("Number of columns doesn't match", ErrorCodes::NUMBER_OF_COLUMNS_DOESNT_MATCH);
    if (add_casted_columns && mode != MatchColumnsMode::Name)
        throw Exception("Converting with add_casted_columns supported only for MatchColumnsMode::Name", ErrorCodes::LOGICAL_ERROR);
    auto actions_dag = std::make_shared<ActionsDAG>(source);