Y2038: seventh draft of the design document and 1st WIP branch

[Albert ARIBAUD <albert.aribaud@3adev.fr>]

Hi all,

I have produced a seventh draft of the Y2038 design document:

https://sourceware.org/glibc/wiki/Y2038ProofnessDesign?rev=153

Relative to the previous draft (to which there were no comments
apparently):

 * Some precisions were added regarding implementation types

 * The location of a WIP implementation branch is provided  

As always, comments welcome on the document.

Regarding the branch, should I post it here as an [RFC] patch series?
Right now, I'm thinking it is not complete enough for a usual RFC,
but I need feedback to know what is in the right direction and what is
not.

For the moment, the branch only targets ARM, not all APIs are
implemented, and some (the stat family) are WIP because at the moment
there are no kernel patches available to provide Y2038-proof stat
syscalls, so the impelmentations skip the "try the 64-bit-time
syscalls if available" part and skip straight to the "fallback to
32-bit, non-Y2038-proof, syscalls" part.

Note: I have created a framework to test the branch, available at
https://github.com/3adev/y2038. It builds tests for an ARM
architecture and runs them in a QEMU ARM system containing a
Y2038-patched kernel, the Y2038 GLIBC WIP branch, a busybox-based
minimal root fs and system, and ad hoc test applications (one built
with -DTIME_BITS=64, one without, for comparison). This too is WIP, as
it progresses alongside the GLIBC branch.

Thanks in advance for your feedback.

Cordialement,
Albert ARIBAUD
3ADEV