The test program (compare-cap) that compares the C and Go library implementations in a single binary, when run via sudo, fails to exit in a state where compare-cap is free of file capabilities.
Looking at cleaning this up...
https://git.kernel.org/pub/scm/libs/libcap/libcap.git/commit/?id=ddbaa98412398a6766552285c8e3c0dcdf632dbb