[PATCH] Fix 32-bit getcwd() on filesystems with 64-bit inodes.

[Nick Alcock]

On 26 Feb 2018, Nix said:

> I'll raise one, probably tomorrow (it's late, I'm tired, and I don't
> want to get it wrong :) ).

Nah, I can't sleep with work outstanding! (or something like that).

This is now #22899 (taken). I have a rather better explanation there,
too, including precisely when it goes wrong (though the fact that it
depends on directory search order makes it hard to reliably reproduce
unless you have lots of > 2^32 inodes in your disconnected subtree).

I'd say that if you ranked bugs by their likely impact, this one is
waaay down there in unimportant territory (you need a 32-bit libc and a
big fs with 64-bit inodes *and* a disconnected subtree). But hey, let's
fix it anyway.

I'll have another patch posted in a few minutes.