Added how? You must do more than simply changing the compile flags.
README of e.g. smbk5pwd for an example of the necessary steps.
I have followed the below instructions:
'If you need to build the overlay statically, you will have to move it into the
slapd/overlays directory and edit the Makefile and overlays.c to reference
it. You will also have to define SLAPD_OVER_SMBK5PWD to SLAPD_MOD_STATIC,
and add the relevant libraries to the main slapd link command.'
However, the above instructions don't seem to 'sufficient' to make use of a
contrib module linked statically. What am I missing here?