The add_sysuser macro in /usr/lib/rpm/macros does not handle 'm' or 'r' type lines from sysuser config files. These are valid types, defined as such in the sysusers.d manpage:

m    Add a user to a group. If the user or group do not exist yet, they will be implicitly created.

r    Add a range of numeric UIDs/GIDs to the pool to allocate new UIDs and GIDs from. If no line of this type is specified, the range of UIDs/GIDs is set to some compiled-in default. Note that both UIDs and GIDs are allocated from the same pool, in order to ensure that users and groups of the same name are likely to carry the same numeric UID and GID.

I don't know if the macro can do anything with r, but it seems it should at least handle g. At the very least it should not claim it's "invalid".

The macro also doesn't ignore comments - lines starting with # - which it probably should. It calls these lines "invalid" as well.

Putting it all together, when building openQA, which includes a sysusers file with this content:

# Type Name            ID     GECOS           [HOME]    Shell
u   _openqa-worker   -     "openQA worker" /var/lib/empty  /bin/bash
m   _openqa-worker  nogroup
m   _openqa-worker  kvm

I see these errors in the build messages:

error: lua script failed: [string "add_sysuser"]:16: invalid sysuser type: #
  3<        (%lua)
  2<      (%add_sysuser)
error: lua script failed: [string "add_sysuser"]:16: invalid sysuser type: m
  3<        (%lua)
  2<      (%add_sysuser)

they don't appear to be fatal, but it seems at least that the user might not be getting the correct groups.