"warning: -jN forced in submake: disabling jobserver mode"

[janekmi]

Please provide a reproduction of the bug:

https://github.com/pmem/pmdk/actions/runs/5732771606/job/15536737481#step:5:3473

How often bug is revealed: always

Actual behavior:

make[1]: warning: -jN forced in submake: disabling jobserver mode.

Expected behavior:

No errors. No warnings.

Additional information about Priority and Help Requested:

Requested priority: Low