I think this is because IList in C# has Count as a signed integer.

So probably the right thing here would be changing mSize to int32_t.

Are you having warnings about this?

Yes (but the warnings are on my side), I was cleaning up the signed and unsigned integer comparisons (in the for loops for example). It's not a big problem, but I was wondering why Count was signed, especially since all the other BaseCollection methods use unsigned indexes.

Having a look at IList in C#, it is interesting that we decided to put int only in Count but not in the other functions also available from C# like RemoveAt(Int32). Not sure why, this is probably a mistake.