Cygwin not respecting --without-newlib?

[Nathanael Nerode]

I've been trying to untangle yet more of the hairy code in top level
configure.in, and I found an interesting item.

When the target is one of 
*-*-cygwin*
powerpc*-*-winnt*
powerpc*-*-pe*
ppc*-*-pe

Newlib is 'always' built, according to the comments.

In fact, if --without-newlib was specified and host=target,
newlib is *not* built.

If --without-newlib was specified and host!=target, newlib *is* built.

However, --with-newlib *isn't* passed down to subconfigures, and
FLAGS_FOR_TARGET isn't set up for newlib.  So it's built but not used by
anything else.

Similar behavior occurs if --without-newlib wasn't specified, but
--with-headers and --with-libs were specified.

I'm quite sure this isn't the correct behavior.  Anyone know what the
correct behavior is?

I'd guess we should never build newlib if --without-newlib is specified,
and the 'always' in the comments should simply mean that we should build
newlib even when host=target.  But that's just my guess.

--Nathanael
neroden@gcc.gnu.org