Non-docker build fails when gRPC installed via package manager

[ghost]

OS: Fedora 29. This is peculiar because it seems to cause the build to fail even though we are explicitly asking for an external project build.

How to reproduce:

• git clone
• Install grpc grpc-devel grpc-plugins protobuf protobuf-compiler protobuf-devel

Then:

mkdir .build && cd .build
cmake .. -DGOOGLE_CLOUD_CPP_DEPENDENCY_PROVIDER=external
make -j4

Output from grpc_project-build-err.log:

--grpc_out: src/proto/grpc/reflection/v1alpha/reflection.proto: cpp grpc proto compiler plugin does not work with generic services. To generate cpp grpc APIs, please set "cc_generic_service = false".
gmake[5]: *** [CMakeFiles/grpc++_reflection.dir/build.make:64: gens/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.cc] Error 1
gmake[4]: *** [CMakeFiles/Makefile2:533: CMakeFiles/grpc++_reflection.dir/all] Error 2
gmake[4]: *** Waiting for unfinished jobs....
--grpc_out: src/proto/grpc/channelz/channelz.proto: cpp grpc proto compiler plugin does not work with generic services. To generate cpp grpc APIs, please set "cc_generic_service = false".
--grpc_out: src/proto/grpc/status/status.proto: cpp grpc proto compiler plugin does not work with generic services. To generate cpp grpc APIs, please set "cc_generic_service = false".
gmake[5]: *** [CMakeFiles/grpc++_error_details.dir/build.make:64: gens/src/proto/grpc/status/status.grpc.pb.cc] Error 1
gmake[5]: *** [CMakeFiles/grpcpp_channelz.dir/build.make:64: gens/src/proto/grpc/channelz/channelz.grpc.pb.cc] Error 1
gmake[4]: *** [CMakeFiles/Makefile2:797: CMakeFiles/grpc++_error_details.dir/all] Error 2
gmake[4]: *** [CMakeFiles/Makefile2:185: CMakeFiles/grpcpp_channelz.dir/all] Error 2
gmake[3]: *** [Makefile:130: all] Error 2

[coryan]

I wonder if the gRPC CMakeLists.txt gets confused, we ask it to build with "package" as a source for Protobuf, because protobuf is installed in the .build/external/ directory, but maybe it is picking up some files from the system package and some from .build/external/?

[ghost]

This looks resolved now.

[ghost]

Spoke too soon. Probably should let the build finish completely before I comment. An improvement (?) is that it now only complains about one proto file instead of three:

--grpc_out: src/proto/grpc/channelz/channelz.proto: cpp grpc proto compiler plugin does not work with generic services. To generate cpp grpc APIs, please set "cc_generic_service = false".
gmake[5]: *** [CMakeFiles/grpcpp_channelz.dir/build.make:64: gens/src/proto/grpc/channelz/channelz.grpc.pb.cc] Error 1
gmake[4]: *** [CMakeFiles/Makefile2:185: CMakeFiles/grpcpp_channelz.dir/all] Error 2

[ghost]

Closing this since it will be superseded by #2802