Hi,

I tried on Mageia Cauldron to build latest 1.30.0 release but it fails to build with:

In file included from ./src/compiler/python_generator_helpers.h:29,
from ./src/compiler/protobuf_plugin.h:24,
from src/compiler/python_generator.cc:35:
./src/compiler/python_generator.h:47:12: error: 'uint64_t grpc_python_generator::PythonGrpcGenerator::GetSupportedFeatures() const' marked 'override', but does not override
47 | uint64_t GetSupportedFeatures() const override;
| ^~~~~~~~~~~~~~~~~~~~
src/compiler/python_generator.cc: In member function 'uint64_t grpc_python_generator::PythonGrpcGenerator::GetSupportedFeatures() const':
src/compiler/python_generator.cc:881:10: error: 'FEATURE_PROTO3_OPTIONAL' was not declared in this scope
881 | return FEATURE_PROTO3_OPTIONAL;
| ^~~~~~~~~~~~~~~~~~~~~~~
make: *** [Makefile:2945: /home/iurt/rpmbuild/BUILD/grpc-1.30.0/objs/opt/src/compiler/python_generator.o] Error 1
make: *** Waiting for unfinished jobs....

Full build log:
build.0.20200625044101.log