Created by: Kontinuation

I encountered an error when building PaddleServing in CLIENT_ONLY mode:

[root@my_host_name build_client]# cmake -DCLIENT_ONLY=ON ..
-- Found Paddle host system: centos, version: 6.10
-- Found Paddle host system's CPU: 12 cores
-- CXX compiler: /opt/rh/devtoolset-2/root/usr/bin/c++, version: GNU 4.8.2
-- C compiler: /opt/rh/devtoolset-2/root/usr/bin/cc, version: GNU 4.8.2
-- Do not have AVX2 intrinsics and disabled MKL-DNN
-- BOOST_TAR: boost_1_41_0, BOOST_URL: http://paddlepaddledeps.cdn.bcebos.com/boost_1_41_0.tar.gz
-- Protobuf protoc executable: /home/Serving/build_client/third_party/install/protobuf/bin/protoc
-- Protobuf-lite library: /home/Serving/build_client/third_party/install/protobuf/lib/libprotobuf-lite.a
-- Protobuf library: /home/Serving/build_client/third_party/install/protobuf/lib/libprotobuf.a
-- Protoc library: /home/Serving/build_client/third_party/install/protobuf/lib/libprotoc.a
-- Protobuf version: 3.1
-- ssl:/usr/lib64/libssl.so
-- crypto:/usr/lib64/libcrypto.so
paddle serving source dir: /home/Serving
CMake Error at core/general-client/CMakeLists.txt:2 (add_subdirectory):
  The source directory

    /home/Serving/core/general-client/pybind11

  does not contain a CMakeLists.txt file.


CMake Error at core/general-client/CMakeLists.txt:3 (pybind11_add_module):
  Unknown CMake command "pybind11_add_module".

The error message says that /home/Serving/core/general-client/pybind11 directory does not contain a CMakeLists.txt file, and it turns out to be an empty directory. pybind11 has been changed to a git submodule in commit 546f1640 , but this submodule is not properly configured, which makes git submodule update command fail.

The folder icon of pybind11 submodule on github is also grey, which indicates that the submodule points to an unreachable location.