bug#50666: 28.0.50; Fix native compilation on Cygwin

[Eli Zaretskii]

> From: ASSI <Stromeko@nexgo.de>
> Cc: Ken Brown <kbrown@cornell.edu>,  50666@debbugs.gnu.org
> Date: Sun, 19 Sep 2021 09:00:46 +0200
> 
> Eli Zaretskii writes:
> > Isn't there a way to rebase a DLL on the fly, when it is loaded?
> 
> There is (of course), but then there is no guarantee that you can do a
> fork from the resulting memory image.  Which is exactly the problem that
> fixing the base addresses of all DLL was intended to solve and has the
> unfortunate side effect that you need to modify the on-disk
> representation.  On 64bit, marking the eln as ASLR w/ high-entropy and
> large address aware will probably work most of the time, but 32bit is
> much more prone to collisions (in fact I did use a shell inside an X11
> Emacs as my test case when I last unsuccessfully tried to make ASLR work
> for Cygwin).

So this basically means that native-compilation is unworkable for
32-bit Cygwin, right?