当我试着为“clickhouse”构建“ninja”时，请帮我找出问题所在
https://clickhouse.yandex/docs/ru/development/build_osx/

SDKs/MacOSX10.15.sdk   -D OS_DARWIN -nostdinc++ -MD -MT dbms/CMakeFiles/dbms.dir/src/Storages/LiveView/StorageLiveView.cpp.o -MF dbms/CMakeFiles/dbms.dir/src/Storages/LiveView/StorageLiveView.cpp.o.d -o dbms/CMakeFiles/dbms.dir/src/Storages/LiveView/StorageLiveView.cpp.o -c ../dbms/src/Storages/LiveView/StorageLiveView.cpp
In file included from ../dbms/src/Storages/LiveView/StorageLiveView.cpp:31:
../dbms/src/Storages/LiveView/LiveViewBlockInputStream.h:188:57: error: use of undeclared identifier 'timestamp'
        last_event_timestamp_usec = static_cast<UInt64>(timestamp.epochMicroseconds());
                                                        ^
1 error generated.
[3313/4079] Building CXX object dbms/CMakeFiles/dbms.dir/src/Client/ConnectionPoolWithFailover.cpp.o
ninja: build stopped: subcommand failed.

另外，我在这里创建了一个请求：https://github.com/clickhouse/clickhouse/issues/8638