Re: Applying patches for RISC-V in crosstool-ng

[Vijay Holimath <vijay.holimath@gmail.com>]

Got it Jim..:) Let me try...

On Tue, Jun 16, 2020 at 3:31 AM Jim Wilson <jimw@sifive.com> wrote:

> On Mon, Jun 15, 2020 at 6:59 AM Vijay Holimath via Gcc-help
> <gcc-help@gcc.gnu.org> wrote:
> > I need to apply this patch:
> >
> https://github.com/bespoke-silicon-group/bsg_manycore/blob/master/software/riscv-tools/newlib.patch
> > for
> > RISC-V and build compiler using crosstool-ng. Can you please tell me how
> to
> > do it?
>
> As Jonathan pointed out this is a crosstools-ng question not a gcc
> question.  But crosstools-ng handles patches like many other tools
> (buildroot, open-embedded, etc).  You just drop a numbered file into
> the package dir, and maybe update a patch file list if they have one.
> I don't think that crosstool-ng has a patch file list.  So trying just
> dropping a file in the right place.  See for instance
> packages/newlib/$VERSION and notice the 0* numbered patch list files.
> You need to know which newlib version you are building so that you put
> the patch file in the right place.
>
> But looking at the patch file, I see that it is a patch file for
> riscv-gnu-toolchain not for newlib.  And the patch file is replacing
> newlib with their own newlib port.  If you want to use crosstools-ng,
> and replace newlib with a different C library, then you need to make a
> change higher up in crosstools-ng.  I don't know offhand how to do
> that.  I would guess that you editing packages/newlib/package.desc to
> use the alternative git tree would work, but that isn't a clear way to
> implement this.  You probably should add the new C library as a new
> package, with a description that points at the alternative git tree,
> and then change the config to use the alternative C library instead of
> newlib.
>
> If you really need to use this patch file, it is probably easier to
> just use github.com/riscv/riscv-gnu-toolchain.  But the patch is from
> last year, so you might need to use a version of riscv-gnu-toolchain
> from last year.
>
> Jim
>