errno constants may exceed the range of representable integers of type int

[glondu]

Hello,

Currently, ocaml-ctypes fails on hurd-i386 because ENOENT there is 1073741826 (0x40000002), which is greater than max_int (1073741823 aka 0x3fffffff). Actually, on Hurd, it seems that all errno constants are greater than 0x40000000.

[glondu]

There seems to be a fundamental problem in ocaml-ctypes: C's int are mapped to OCaml's int (as far as I understand). In Signed, Int.t should be abstract, like Long.t and LLong.t, and defined using pick and sizeof(int). I started to do this, but it requires many changes in the test-suite, which makes me think that change will break a lot of existing codebase. I'm tempted to try an alternative: leave Int.t concrete, and introduce a new abstract type for errno (that can of course be used elsewhere). Any opinions? Am I missing something?