Looks like isUV flag isn't set when ULL PDL is converted to Perl scalars

[vadim-160102]

This conversion is implicit in stringification (e.g. in REPL), and therefore easy to demonstrate:

Perl executable: C:\berrybrew\strawberry-perl-5.38.0.1-64bit-PDL\perl\bin\perl.exe
Perl version   : 5.38.0 / MSWin32-x64-multi-thread
PDL version    : 2.084

pdl> p $u = pdl(ulonglong, [0,1])
[0 1]
pdl> p $u-> info
PDL: ULongLong D [2]
pdl> p $uu = ~ $u
[-1 -2]
pdl> p $uu-> info
PDL: ULongLong D [2]
pdl> p abs $uu
[-1 -2]
pdl> p $uu > 0
[1 1]
pdl> p $uu-> unpdl-> @*
-1 -2

[mohawk2]

Thank you for the report! This will be getting released quite soon.