Hi Jens, Sorry for the slow reply.
This error indicates that the KJ EventLoop (which is part of the objects returned by kj::setupAsyncIo()) was destroyed while some kj::Promise objects still existed. Ideally, you should set things up so that when the stack unwinds, all Promise objects are destroyed before the EventLoop is destroyed. Alternatively, make sure to catch all exceptions at the top level such that the EventLoop is never destroyed. -Kenton On Mon, May 23, 2022 at 6:15 PM Jens Alfke <j...@mooseyard.com> wrote: > I’m in the midst of improving the error handling in my code, but there’s a > warning logged by KJ that I can’t figure out. I’d appreciate any advice or > insight. > > It happens when my client code fails to connect because server-side auth > fails, so it gets an abrupt "Connection reset by peer” error that’s thrown > from the first Promise::wait() call. That exception causes my client object > to get destructed, and during its destructor the warning gets logged (with > a bunch of backtrace.) > > The message as logged from my onRecoverableException handler looks like: > > expected head == nullptr [10bf07390 == nullptr]; EventLoop destroyed with > events still in the queue. Memory leak?; head->traceEvent() = 10152fc4c > 101548a28 > kj::_::ImmediatePromiseNode<kj::Own<capnp::ClientHook> > >::get(kj::_::ExceptionOrValue&) (in myapp) + 0: returning here > > The call stack is pretty long, so I’ve tried to clean it up a bit. “myapp” > is app code. “snej::shs” is my implementation of the SecretHandshake > secure-socket protocol, including CapnP glue code adapted from ez-rpc.c++. > > myapp::KJExceptionCallback::onRecoverableException() at Logging.cc:80 > <http://logging.cc:80>:28 > kj::_::Debug::Fault::~Fault() + 172 > kj::EventLoop::~EventLoop() + 432 > kj::_::HeapDisposer<kj::() const + 56 > kj::Disposer::Dispose_<kj::LowLevelAsyncIoProvider, true>::dispose() at > memory.h:522:14 > void kj::Disposer::dispose<kj::LowLevelAsyncIoProvider>() const at > memory.h:534:3 > kj::Own<kj::LowLevelAsyncIoProvider>::dispose() at memory.h:278:17 > kj::Own<kj::LowLevelAsyncIoProvider>::~Own() at memory.h:204:28 > kj::Own<kj::LowLevelAsyncIoProvider>::~Own() at memory.h:204:26 > kj::AsyncIoContext::~AsyncIoContext() at async-io.h:876:8 > kj::AsyncIoContext::~AsyncIoContext() at async-io.h:876:8 > snej::shs::SecretRPCContext::~SecretRPCContext() at SecretRPC.cc:56 > <http://secretrpc.cc:56>:9 > snej::shs::SecretRPCContext::~SecretRPCContext() at SecretRPC.cc:50 > <http://secretrpc.cc:50>:45 > snej::shs::SecretRPCContext::~SecretRPCContext() at SecretRPC.cc:50 > <http://secretrpc.cc:50>:45 > kj::Disposer::Dispose_<snej::shs::SecretRPCContext, true>::dispose() at > memory.h:522:14 > void kj::Disposer::dispose<snej::shs::SecretRPCContext>() const at > memory.h:534:3 > kj::Own<snej::shs::SecretRPCContext>::dispose() at memory.h:278:17 > kj::Own<snej::shs::SecretRPCContext>::~Own() at memory.h:204:28 > kj::Own<snej::shs::SecretRPCContext>::~Own() at memory.h:204:26 > snej::shs::SecretRPCClient::Impl::~Impl() at SecretRPC.cc:283 > <http://secretrpc.cc:283>:29 > snej::shs::SecretRPCClient::Impl::~Impl() at SecretRPC.cc:283 > <http://secretrpc.cc:283>:29 > kj::_::HeapDisposer<snej::shs::SecretRPCClient::Impl>::disposeImpl() const > at memory.h:433:60 > kj::Disposer::Dispose_<snej::shs::SecretRPCClient::Impl, false>::dispose() > at memory.h:528:14 > void kj::Disposer::dispose<snej::shs::SecretRPCClient::Impl>() const at > memory.h:534:3 > kj::Own<snej::shs::SecretRPCClient::Impl>::dispose() at memory.h:278:17 > kj::Own<snej::shs::SecretRPCClient::Impl>::~Own() at memory.h:204:28 > kj::Own<snej::shs::SecretRPCClient::Impl>::~Own() at memory.h:204:26 > snej::shs::SecretRPCClient::~SecretRPCClient() at SecretRPC.cc:383 > <http://secretrpc.cc:383>:59 > snej::shs::SecretRPCClient::~SecretRPCClient() at SecretRPC.cc:383 > <http://secretrpc.cc:383>:57 > kj::_::HeapDisposer<snej::shs::SecretRPCClient>::disposeImpl() const at > memory.h:433:60 > kj::Disposer::Dispose_<snej::shs::SecretRPCClient, false>::dispose() at > memory.h:528:14 > void kj::Disposer::dispose<snej::shs::SecretRPCClient>() const at > memory.h:534:3 > kj::Own<snej::shs::SecretRPCClient>::dispose() at memory.h:278:17 > kj::Own<snej::shs::SecretRPCClient>::~Own() at memory.h:204:28 > kj::Own<snej::shs::SecretRPCClient>::~Own() at memory.h:204:26 > myapp::net::Client::ConnectionImpl::~ConnectionImpl() at Client.cc:281 > <http://client.cc:281>:19 > myapp::net::Client::ConnectionImpl::~ConnectionImpl() at Client.cc:281 > <http://client.cc:281>:19 > myapp::net::Client::ConnectionImpl::~ConnectionImpl() at Client.cc:281 > <http://client.cc:281>:19 > std::__1::default_delete<myapp::net::Client::Impl>::operator() const at > unique_ptr.h:57:5 > std::__1::unique_ptr<myapp::net::Client::Impl, > std::__1::default_delete<myapp::net::Client::Impl> >::reset() at > unique_ptr.h:318:7 > std::__1::unique_ptr<myapp::net::Client::Impl, > std::__1::default_delete<myapp::net::Client::Impl> >::~unique_ptr() at > unique_ptr.h:272:19 > std::__1::unique_ptr<myapp::net::Client::Impl, > std::__1::default_delete<myapp::net::Client::Impl> >::~unique_ptr() at > unique_ptr.h:272:17 > myapp::net::Client::~Client() at Client.cc:314 <http://client.cc:314>:21 > myapp::net::Client::~Client() at Client.cc:314 <http://client.cc:314>:21 > myapp::SyncTask::_run() at SyncTask.cc:166 <http://synctask.cc:166>:5 > myapp::SyncTask::run() const at SyncTask.cc:82 <http://synctask.cc:82>:9 > kj::_::RunnableImpl<myapp::SyncTask::run() at exception.h:319:5 > kj::_::runCatchingExceptions() + 36 > kj::Maybe<kj::Exception> kj::runCatchingExceptions<myapp::SyncTask::run() > at exception.h:332:10 > myapp::SyncTask::run() at SyncTask.cc:82 <http://synctask.cc:82>:9 > SyncCommand::runSubcommand() at ClientMain.cc:842 > <http://clientmain.cc:842>:24 > InteractiveTool::runSubcommand() at InteractiveTool.cc:72 > <http://interactivetool.cc:72>:29 > myappClient::run() at ClientMain.cc:178 <http://clientmain.cc:178>:13 > Tool::main() at Tool.hh:63:20 > main() at ClientMain.cc:188 <http://clientmain.cc:188>:28 > > -- > You received this message because you are subscribed to the Google Groups > "Cap'n Proto" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to capnproto+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/capnproto/59C02C00-95D1-4357-8F26-9E3F8A1C35DC%40mooseyard.com > <https://groups.google.com/d/msgid/capnproto/59C02C00-95D1-4357-8F26-9E3F8A1C35DC%40mooseyard.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Cap'n Proto" group. To unsubscribe from this group and stop receiving emails from it, send an email to capnproto+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/capnproto/CAJouXQnksfei9ZiAn6hKn99Kxse-5U_xvN0jtcZ0aGfaH2wzvg%40mail.gmail.com.
