[Buildroot] [PATCH v2 2/6] zstd: add host libzstd support

[Peter Seiderer <ps.report@gmx.net>]

Hello Yann,

On Wed, 11 Apr 2018 23:19:07 +0200, "Yann E. MORIN" <yann.morin.1998@free.fr> wrote:

> Peter, All,
> 
> On 2018-04-09 22:04 +0200, Peter Seiderer spake thusly:
> > Signed-off-by: Peter Seiderer <ps.report@gmx.net>
> > ---
> > Changes v1 -> v2:
> >   - split off host libzstd support (suggested by Yann E. MORIN)
> >   - no ZSTD_OPTS for host libarary build
> > ---
> >  package/zstd/zstd.mk | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> > diff --git a/package/zstd/zstd.mk b/package/zstd/zstd.mk
> > index c0fa88026c..1b76b0164c 100644
> > --- a/package/zstd/zstd.mk
> > +++ b/package/zstd/zstd.mk
> > @@ -46,4 +46,16 @@ define ZSTD_INSTALL_TARGET_CMDS
> >  		DESTDIR=$(TARGET_DIR) PREFIX=/usr -C $(@D)/programs install
> >  endef
> >  
> > +# note: no 'HAVE_...' options for host library build only 
> > +define HOST_ZSTD_BUILD_CMDS
> > +	$(HOST_MAKE_ENV) $(HOST_CONFIGURE_OPTS) $(MAKE) \
> > +		-C $(@D) lib
> > +endef
> > +
> > +define HOST_ZSTD_INSTALL_CMDS
> > +	$(HOST_MAKE_ENV) $(HOST_CONFIGURE_OPTS) $(MAKE) \
> > +		DESTDIR=$(HOST_DIR) PREFIX=/usr -C $(@D)/lib install
> > +endef
> > +
> >  $(eval $(generic-package))
> > +$(eval $(host-generic-package))  
> 
> The target variant has optional dependencies on zlib, xz, and lz4, which
> all have host variants.

The zlibx/xz/lz4 support options apply only to the cmdline tools, not
to the libzst libary (the only build target for the host variant),
see the (short) comment about the 'HAVE_...' options...
> 
> So, if you don;t specify the dependency in the host-zstd, you get a
> host-zstd that may or may not have support for zlib, xz, or lz4,
> depending on hether another package a dependency on them.
> 
> We don't have spport for optional host dependencies (because there are
> not config options for those host packages), so I don't see a solution
> but to always depend on all three. So:
> 
>     HOST_ZSTD_DEPENDENCIES = host-lz4 host-xz host-zlib

So no need for the host library build to depend on (unused) lz4/xz/zlib
host-builds....

Regards,
Peter

> 
> Regards,
> Yann E. MORIN.
>