CMake Warning:
  Manually-specified variables were not used by the project:

    CMAKE_EXPORT_NO_PACKAGE_REGISTRY


In file included from /home/conan/w/cci_PR-4776/.conan/data/protobuf/3.15.4/_/_/build/4f56a9e98bd6d90e81c4ef9d30b23b876aee5a2e/source_subfolder/src/google/protobuf/any.cc:36:
/home/conan/w/cci_PR-4776/.conan/data/protobuf/3.15.4/_/_/build/4f56a9e98bd6d90e81c4ef9d30b23b876aee5a2e/source_subfolder/src/google/protobuf/message.h:234:13: error: constexpr constructor never produces a constant expression [-Winvalid-constexpr]
  constexpr Message() {}
            ^
/home/conan/w/cci_PR-4776/.conan/data/protobuf/3.15.4/_/_/build/4f56a9e98bd6d90e81c4ef9d30b23b876aee5a2e/source_subfolder/src/google/protobuf/message.h:234:13: note: non-literal type 'google::protobuf::MessageLite' cannot be used in a constant expression
1 error generated.
make[2]: *** [source_subfolder/cmake/CMakeFiles/libprotobuf.dir/__/src/google/protobuf/any.cc.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [source_subfolder/cmake/CMakeFiles/libprotobuf.dir/all] Error 2
make: *** [all] Error 2
protobuf/3.15.4: WARN: Build folder is dirty, removing it: /home/conan/w/cci_PR-4776/.conan/data/protobuf/3.15.4/_/_/build/4f56a9e98bd6d90e81c4ef9d30b23b876aee5a2e
protobuf/3.15.4: ERROR: Package '4f56a9e98bd6d90e81c4ef9d30b23b876aee5a2e' build failed
protobuf/3.15.4: WARN: Build folder /home/conan/w/cci_PR-4776/.conan/data/protobuf/3.15.4/_/_/build/4f56a9e98bd6d90e81c4ef9d30b23b876aee5a2e
ERROR: protobuf/3.15.4: Error in build() method, line 157
	cmake.build()
	ConanException: Error 2 while executing cmake --build '/home/conan/w/cci_PR-4776/.conan/data/protobuf/3.15.4/_/_/build/4f56a9e98bd6d90e81c4ef9d30b23b876aee5a2e/build_subfolder' '--' '-j3'