[RFC][AArch64] Support in-tree building with libgloss and linker scripts (specs files)

[Marcus Shawcroft]

On 24 January 2014 14:46, Richard Earnshaw <rearnsha@arm.com> wrote:
> When using libgloss and linker scripts unified source tree builds
> (gcc+newlib+binutils) fail when building the libraries because the
> linker scripts have not been installed at that time.
>
> A suitable solution to this is to make copies of the scripts in the
> build area, which the compiler is configured to search during the build.
>  Then using LDFLAGS_FOR_TARGET=-specs=<spec-file> flag will correctly
> pick up the appropriate libgloss specs file.
>
> I've marked this as an RFC as I'm not sure if the pattern-based rule is
> GNUmake specific, and if it is, whether this is not appropriate for
> newlib -- it could be written out long-hand, but this rule makes the
> construct trivial to port to other libgloss targets.
>
> This was the only patch I needed to make an aarch64-elf unified tree
> build and run the gcc testsuite.
>
> Thoughts please?

Installing the scripts in the build area makes sense to me, but I
think we need an ack from Jeff or Corinna w.r.t the use of GNU make
extensions.

Cheers
/Marcus