==19==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x7fbd5d6f2d94 in grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::StartCall() /proc/self/cwd/include/grpcpp/impl/codegen/client_callback.h:318:9
    #1 0x7663d6 in grpc::experimental::ClientBidiReactor<grpc::ByteBuffer, grpc::ByteBuffer>::StartCall() /proc/self/cwd/external/com_github_grpc_grpc/include/grpcpp/impl/codegen/client_callback.h:166:31
    #2 0x5688e2 in grpc::testing::(anonymous namespace)::ClientCallbackEnd2endTest::SendGenericEchoAsBidi(int)::Client::Client(grpc::testing::(anonymous namespace)::ClientCallbackEnd2endTest*, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) /proc/self/cwd/test/cpp/end2end/client_callback_end2end_test.cc:201:11
    #3 0x563a2b in grpc::testing::(anonymous namespace)::ClientCallbackEnd2endTest::SendGenericEchoAsBidi(int) /proc/self/cwd/test/cpp/end2end/client_callback_end2end_test.cc:229:9
    #4 0x5625ee in grpc::testing::(anonymous namespace)::ClientCallbackEnd2endTest_SequentialGenericRpcsAsBidi_Test::TestBody() /proc/self/cwd/test/cpp/end2end/client_callback_end2end_test.cc:265:3
    #5 0xf0cdd8 in void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:2402:10
    #6 0xd376d7 in void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:2438:14
    #7 0xa9fb66 in testing::Test::Run() /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:2474:5
    #8 0xaad90b in testing::TestInfo::Run() /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:2656:11
    #9 0xac3ac4 in testing::TestCase::Run() /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:2774:28
    #10 0xb75ce1 in testing::internal::UnitTestImpl::RunAllTests() /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:4649:43
    #11 0xf571b3 in bool testing::internal::HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:2402:10
    #12 0xd5841f in bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:2438:14
    #13 0xb725b8 in testing::UnitTest::Run() /proc/self/cwd/external/com_github_google_googletest/googletest/src/gtest.cc:4257:10
    #14 0x6205a5 in RUN_ALL_TESTS() /proc/self/cwd/external/com_github_google_googletest/googletest/include/gtest/gtest.h:2233:46
    #15 0x4e9a3f in main /proc/self/cwd/test/cpp/end2end/client_callback_end2end_test.cc:500:10
    #16 0x7fbd545b182f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f)
    #17 0x463978 in _start (/b/f/w/bazel-out/k8-fastbuild/bin/test/cpp/end2end/client_callback_end2end_test@poller=epoll1.runfiles/com_github_grpc_grpc/test/cpp/end2end/client_callback_end2end_test+0x463978)
  Memory was marked as uninitialized
    #0 0x48ee1f in __sanitizer_dtor_callback /tmp/clang-build/src/compiler-rt/lib/msan/msan_interceptors.cc:931:3
    #1 0x7fbd5d6f1380 in grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::~ClientCallbackReaderWriterImpl() /proc/self/cwd/include/grpcpp/impl/codegen/client_callback.h:240:7
    #2 0x7fbd5d722a88 in grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::MaybeFinish() /proc/self/cwd/include/grpcpp/impl/codegen/client_callback.h:260:14
    #3 0x7fbd5d750b29 in grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::StartCall()::'lambda2'(bool)::operator()(bool) const /proc/self/cwd/include/grpcpp/impl/codegen/client_callback.h:308:53
    #4 0x7fbd5d7508b5 in __invoke<(lambda at include/grpcpp/impl/codegen/client_callback.h:308:35) &, bool> /usr/local/bin/../include/c++/v1/type_traits:4356:1
    #5 0x7fbd5d7508b5 in void std::__1::__invoke_void_return_wrapper<void>::__call<grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::StartCall()::'lambda2'(bool)&, bool>(grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::StartCall()::'lambda2'(bool)&, bool&&) /usr/local/bin/../include/c++/v1/__functional_base:349
    #6 0x7fbd5d74f670 in std::__1::__function::__func<grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::StartCall()::'lambda2'(bool), std::__1::allocator<grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::StartCall()::'lambda2'(bool)>, void (bool)>::operator()(bool&&) /usr/local/bin/../include/c++/v1/functional:1563:12
    #7 0x6c2a7f in std::__1::function<void (bool)>::operator()(bool) const /usr/local/bin/../include/c++/v1/functional:1914:12
    #8 0x6c23e1 in void grpc::internal::CatchingCallback<std::__1::function<void (bool)>&, bool&>(std::__1::function<void (bool)>&, bool&) /proc/self/cwd/external/com_github_grpc_grpc/include/grpcpp/impl/codegen/callback_common.h:39:5
    #9 0x6c1f2f in grpc::internal::CallbackWithSuccessTag::Run(bool) /proc/self/cwd/external/com_github_grpc_grpc/include/grpcpp/impl/codegen/callback_common.h:192:7
    #10 0x6c1522 in grpc::internal::CallbackWithSuccessTag::StaticRun(grpc_experimental_completion_queue_functor*, int) /proc/self/cwd/external/com_github_grpc_grpc/include/grpcpp/impl/codegen/callback_common.h:182:47
    #11 0x7fbd5b11029c in cq_end_op_for_callback(grpc_completion_queue*, void*, grpc_error*, void (*)(void*, grpc_cq_completion*), void*, grpc_cq_completion*) /proc/self/cwd/src/core/lib/surface/completion_queue.cc:871:3
    #12 0x7fbd5b0fbf06 in grpc_cq_end_op(grpc_completion_queue*, void*, grpc_error*, void (*)(void*, grpc_cq_completion*), void*, grpc_cq_completion*) /proc/self/cwd/src/core/lib/surface/completion_queue.cc:877:3
    #13 0x7fbd5b0c690e in post_batch_completion(batch_control*) /proc/self/cwd/src/core/lib/surface/call.cc:1209:5
    #14 0x7fbd5b0b9e89 in finish_batch_step(batch_control*) /proc/self/cwd/src/core/lib/surface/call.cc:1217:5
    #15 0x7fbd5b0b39ef in receiving_trailing_metadata_ready(void*, grpc_error*) /proc/self/cwd/src/core/lib/surface/call.cc:1472:3
    #16 0x7fbd5af219d8 in exec_ctx_run(grpc_closure*, grpc_error*) /proc/self/cwd/src/core/lib/iomgr/exec_ctx.cc:40:3
    #17 0x7fbd5d3b71a8 in grpc_closure_run(char const*, int, grpc_closure*, grpc_error*) /proc/self/cwd/./src/core/lib/iomgr/closure.h:259:5
    #18 0x7fbd5d3a2092 in recv_trailing_metadata_ready(void*, grpc_error*) /proc/self/cwd/src/core/ext/filters/message_size/message_size_filter.cc:221:3
    #19 0x7fbd5af219d8 in exec_ctx_run(grpc_closure*, grpc_error*) /proc/self/cwd/src/core/lib/iomgr/exec_ctx.cc:40:3
    #20 0x7fbd5d3b71a8 in grpc_closure_run(char const*, int, grpc_closure*, grpc_error*) /proc/self/cwd/./src/core/lib/iomgr/closure.h:259:5
SUMMARY: MemorySanitizer: use-of-uninitialized-value /proc/self/cwd/include/grpcpp/impl/codegen/client_callback.h:318:9 in grpc::internal::ClientCallbackReaderWriterImpl<grpc::ByteBuffer, grpc::ByteBuffer>::StartCall()