link error with SSL_* symbols

[zopyx]

I am trying to compile a fresh checkout on Ubuntu 20.10 and get this error while linking:

/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `ENGINE_cleanup'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `SSL_get_ex_new_index'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `SSLv23_method'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `ERR_free_strings'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `SSL_load_error_strings'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `SSL_library_init'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `OPENSSL_add_all_algorithms_noconf'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `EVP_cleanup'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `CRYPTO_set_id_callback'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `CRYPTO_set_locking_callback'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `CRYPTO_num_locks'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `CRYPTO_cleanup_all_ex_data'
/usr/bin/ld: ../../src/backend/polar_dma/lib//libpolar_consensus_wrapper.so: undefined reference to `CRYPTO_mem_leaks_fp'
collect2: error: ld returned 1 exit status
make[2]: *** [Makefile:71: postgres] Error 1
make[2]: Leaving directory '/home/ajung/src/PolarDB-for-PostgreSQL/src/backend'
make[1]: *** [Makefile:42: all-backend-recurse] Error 2
make[1]: Leaving directory '/home/ajung/src/PolarDB-for-PostgreSQL/src'
make: *** [GNUmakefile:11: all-src-recurse] Error 2

[polardb-open]

It needs openssl to be installed. See https://github.com/alibaba/PolarDB-for-PostgreSQL#deployment-from-source-code for dependency.

[polardb-open]

see #9 (comment) for more information

[yuwei-michael]

Paxos library will open source soon, please wait for a while.

[mengborong]

Hi, @zopyx. consensus dynamic lib has been replaced by source code. When running build.sh on top directory, it will be rebuilt.