Hello,
I've noticed that with the uclibc-ng 1.0.39 the tests tst-cancel18 and tst-cancelx18 are failing in NPTL-enabled configs (on xtensa). Bisection pointed me to the commit 08d46f1ce21e ("librt: avoid compilation error") which effectively turned off cancellation for clock_nanosleep.
Reverting it fixes the tests for me, and does not break uclibc-ng build on nommu configs with or without threads support.
So I'm curious what was the original issue that mentioned commit tried to solve (what arch/config)?