QCheck.Gen.{ui32,ui64} not unsigned

[jmid]

The current documentation https://c-cube.github.io/qcheck/0.22/qcheck-core/QCheck/Gen/index.html#val-ui32
says

val ui32 : int32 t
Generates (unsigned) int32 values.

val ui64 : int64 t
Generates (unsigned) int64 values.

However that seems off, as I'm seeing several negative outputs:

# QCheck.Gen.(generate ~n:10 ui32);;
- : int32 list =
[63427152l; 326131724l; 908231618l; -1692656491l; 676133865l; 1856308549l;
 -163216644l; -540852095l; -943426166l; 30873897l]
# QCheck.Gen.(generate ~n:10 ui64);;
- : int64 list =
[-3254598462914660785L; -6544335298499621736L; 6894849975125638767L;
 -4841072242772461851L; 5942088625874337353L; -4146767578361986769L;
 -6246245497190989365L; 2057086657278494593L; 1640197283483944504L;
 4458365409476190594L]