[boost] Problem building Ceph 14.2.15 with libboost 1.74.0

7 Jan 2021

      Hi,

I'm the Debian package maintainer for Ceph. Ceph currently fails to
build with latest libbost. Here's the build log:

/root/ceph/src/common/async/completion.h:194:29: error:
'boost::asio::executor_work_guardboost::asio::execution_context&,
boost::asio::execution::detail::blocking::never_t<0>,
boost::asio::execution::prefer_only
...
,
boost::asio::execution::prefer_only
,
boost::asio::execution::prefer_only
,
boost::asio::execution::prefer_only
,
boost::asio::execution::prefer_only
...
, void>::executor_type' {aka 'class
boost::asio::execution::any_executorboost::asio::execution_context&,
boost::asio::execution::detail::blocking::never_t<0>,
boost::asio::execution::prefer_only
,
boost::asio::execution::prefer_only
,
boost::asio::execution::prefer_only
,
boost::asio::execution::prefer_only
,
boost::asio::execution::prefer_only
'} has no member named 'defer'; did you mean 'prefer'?
  194 |     w.second.get_executor().defer(std::move(f), alloc2);
and 3 more like this. The code doing this is in
src/common/async/completion.h:

  void destroy_defer(std::tuple&& args) override {
    auto w = std::move(work);
    auto f = bind_and_forward(std::move(handler), std::move(args));
    RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler);
    RebindTraits2::destroy(alloc2, this);
    RebindTraits2::deallocate(alloc2, this, 1);
    w.second.get_executor().defer(std::move(f), alloc2);
  }
  void destroy_dispatch(std::tuple&& args) override {
    auto w = std::move(work);
    auto f = bind_and_forward(std::move(handler), std::move(args));
    RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler);
    RebindTraits2::destroy(alloc2, this);
    RebindTraits2::deallocate(alloc2, this, 1);
    w.second.get_executor().dispatch(std::move(f), alloc2);
  }
  void destroy_post(std::tuple&& args) override {
    auto w = std::move(work);
    auto f = bind_and_forward(std::move(handler), std::move(args));
    RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler);
    RebindTraits2::destroy(alloc2, this);
    RebindTraits2::deallocate(alloc2, this, 1);
    w.second.get_executor().post(std::move(f), alloc2);
  }

Has the boost API changed? If so, how to fix the above code?

Thanks a lot to anyone helping me fixing this,
Cheers,

Thomas Goirand (zigo)