bfd/docs building on Cygwin

[Alan Modra]

On Mon, Feb 08, 2021 at 01:20:12PM +0100, Jan Beulich wrote:
> In bba33ab1e0f7 ("Fix build without makeinfo from release
> binutils tar") uses of "cp -p" were introduced, to work
> around a build problem (which arguably was easy enough to
> work around by passing MAKEINFO=true on the make command
> line, as I've been doing under Cygwin for a long time).
> The previous Cygwin version I had been using was quite old,
> so I've noticed the new issue only after recently having
> installed an up-to-date one.
> 
> The problem is with "cp -p" trying to preserve ownership:
> With the sources living on a Samba share I observe this
> failing with "Permission denied". Looking at the purpose of
> the copying I wonder why copies are being made in the first
> place. Would the change below (suitably propagated to
> Makefile.in of course) be an acceptable alternative?

Yes, "ln -s" should be OK (and of course $(LN_S) falls back to
"cp -p" where symbolic links are not supported).
Patch approved.

> (Seeing the not insignificant amount of redundancy here:
> Isn't the binutils build system implying GNU make anyway,
> for vpath support? If so, is there a reason all these
> individual rules couldn't be consolidated into a few
> pattern rules?)

I don't see a problem in requiring GNU make to build binutils, but
that should be formalised by saying so in binutils/README.

-- 
Alan Modra
Australia Development Lab, IBM