error on make

[rforcen]

cmake --version cmake version 3.22.1

[ mkdir build; cd build; cmake .. ]

cmake .. CMake Deprecation Warning at CMakeLists.txt:1 (cmake_minimum_required): Compatibility with CMake < 2.8.12 will be removed from a future version of CMake.

Update the VERSION argument value or use a ... suffix to tell CMake that the project does not need compatibility with older versions.

-- The C compiler identification is GNU 11.4.0 -- The CXX compiler identification is GNU 11.4.0 -- Detecting C compiler ABI info -- Detecting C compiler ABI info - done -- Check for working C compiler: /usr/bin/cc - skipped -- Detecting C compile features -- Detecting C compile features - done -- Detecting CXX compiler ABI info -- Detecting CXX compiler ABI info - done -- Check for working CXX compiler: /usr/bin/c++ - skipped -- Detecting CXX compile features -- Detecting CXX compile features - done -- Configuring done -- Generating done -- Build files have been written to: /home/asd/Downloads/cbor-cpp/build

asd@pop-os:~/Downloads/cbor-cpp/build$ make [ 6%] Building CXX object CMakeFiles/cborcpp.dir/src/encoder.cpp.o [ 13%] Building CXX object CMakeFiles/cborcpp.dir/src/decoder.cpp.o [ 20%] Building CXX object CMakeFiles/cborcpp.dir/src/input.cpp.o [ 26%] Building CXX object CMakeFiles/cborcpp.dir/src/listener_debug.cpp.o [ 33%] Building CXX object CMakeFiles/cborcpp.dir/src/output_dynamic.cpp.o [ 40%] Building CXX object CMakeFiles/cborcpp.dir/src/output_static.cpp.o [ 46%] Linking CXX shared library libcborcpp.so [ 46%] Built target cborcpp [ 53%] Building CXX object CMakeFiles/testing.dir/src/encoder.cpp.o [ 60%] Building CXX object CMakeFiles/testing.dir/src/decoder.cpp.o [ 66%] Building CXX object CMakeFiles/testing.dir/src/input.cpp.o [ 73%] Building CXX object CMakeFiles/testing.dir/src/listener_debug.cpp.o [ 80%] Building CXX object CMakeFiles/testing.dir/src/output_dynamic.cpp.o [ 86%] Building CXX object CMakeFiles/testing.dir/src/output_static.cpp.o [ 93%] Building CXX object CMakeFiles/testing.dir/src/tests.cpp.o /home/asd/Downloads/cbor-cpp/src/tests.cpp: In function ‘int main()’: /home/asd/Downloads/cbor-cpp/src/tests.cpp:42:30: error: cannot declare variable ‘listener’ to be of abstract type ‘cbor::listener_debug’ 42 | cbor::listener_debug listener; | ^~~~~~~~ In file included from /home/asd/Downloads/cbor-cpp/src/cbor.h:26, from /home/asd/Downloads/cbor-cpp/src/tests.cpp:19: /home/asd/Downloads/cbor-cpp/src/listener_debug.h:25:11: note: because the following virtual functions are pure within ‘cbor::listener_debug’: 25 | class listener_debug : public listener { | ^~~~~~~~~~~~~~ In file included from /home/asd/Downloads/cbor-cpp/src/decoder.h:21, from /home/asd/Downloads/cbor-cpp/src/cbor.h:22, from /home/asd/Downloads/cbor-cpp/src/tests.cpp:19: /home/asd/Downloads/cbor-cpp/src/listener.h:27:22: note: ‘virtual void cbor::listener::on_float32(float)’ 27 | virtual void on_float32(float value) = 0; | ^~~~~~~~~~ /home/asd/Downloads/cbor-cpp/src/listener.h:28:22: note: ‘virtual void cbor::listener::on_double(double)’ 28 | virtual void on_double(double value) = 0; | ^~~~~~~~~ make[2]: *** [CMakeFiles/testing.dir/build.make:160: CMakeFiles/testing.dir/src/tests.cpp.o] Error 1 make[1]: *** [CMakeFiles/Makefile2:111: CMakeFiles/testing.dir/all] Error 2 make: *** [Makefile:91: all] Error 2