Skip ld/lto tests if plugins is disabled for binutils?

[Alan Modra]

On Tue, Aug 12, 2014 at 10:51:56AM +0800, Bin.Cheng wrote:
> On Mon, Aug 11, 2014 at 8:59 PM, Alan Modra <amodra@gmail.com> wrote:
> > So ld plugin support is always enabled, even when you configure with
> > --disable-plugins.  That seems wrong to me.
> 
> Hi Alan, I searched around and found out that there was bug report on
> this before at https://sourceware.org/bugzilla/show_bug.cgi?id=12402
> 
> It was resolved as invalid and said this is designed behavior, though

Yeah, Richard Henderson thought it best that way
https://sourceware.org/ml/binutils/2010-10/msg00074.html

> I am not convinced.
> With this, the only choice is to enable-plugin for binutils?

Yes.

Nowadays, with gcc defaulting to -fno-fat-lto-objects you really don't
have a fully functional lto toolchain unless the ar/nm/ranlib plugin
is enabled.

I think we should make --enable-plugins default to yes, and make
ld/configure.ac respect --enable-plugins=no.

-- 
Alan Modra
Australia Development Lab, IBM