Problem when compiling and loading on Alpine with Mosquitto 1.5.5

[danielfaust]

I'm trying to use this plugin in an Alpine Docker image but I'm having a problem where I'm getting the message mosquitto_log_printf: symbol not found

/usr/lib # mosquitto -c /mosquitto/config/mosquitto.conf
1547298826: mosquitto version 1.5.5 starting
1547298826: Config loaded from /mosquitto/config/mosquitto.conf.
1547298826: Error: Unable to load auth plugin "/usr/lib/auth_plugin_pyauth.so".
1547298826: Load error: Error relocating /usr/lib/auth_plugin_pyauth.so: mosquitto_log_printf: symbol not found

Here is some further info about the compiled plugin.

/usr/lib # ldd auth_plugin_pyauth.so
ldd (0x7f7476986000)
libpython2.7.so.1.0 => /usr/lib/libpython2.7.so.1.0 (0x7f74763de000)
libmosquitto.so.1 => /usr/lib/libmosquitto.so.1 (0x7f74761cf000)
libc.musl-x86_64.so.1 => ldd (0x7f7476986000)
libssl.so.45 => /lib/libssl.so.45 (0x7f7475f83000)
libcrypto.so.43 => /lib/libcrypto.so.43 (0x7f7475bd8000)
Error relocating auth_plugin_pyauth.so: mosquitto_log_printf: symbol not found
Error relocating auth_plugin_pyauth.so: mosquitto_client_username: symbol not found
Error relocating auth_plugin_pyauth.so: mosquitto_client_id: symbol not found
/usr/lib #

What could be causing this, and how can I resolve this issue?

I'm compiling it during Docker build, right after compiling Mosquitto. It's only those three symbols which are not found, I would have expected all of the mosquitto_* symbols not getting found, but not just a couple of them.