Re: [dpdk-dev] [PATCH v2] mk: link combined shared lib using CC

["Gonzalez Monroy, Sergio" <sergio.gonzalez.monroy@intel.com>]

> From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> Sent: Tuesday, December 16, 2014 11:43 PM
> 
> 2014-12-16 19:48, Thomas Monjalon:
> > 2014-10-28 15:48, Sergio Gonzalez Monroy:
> > > If we set EXTRA_CFLAGS=-O0, build fails with following error:
> > >
> > > /usr/bin/ld: test: hidden symbol `mknod' in
> > > /usr/lib64/libc_nonshared.a(mknod.oS) is referenced by DSO
> > >
> > > Fix: link combined shared lib using CC if LINK_USING_CC is enabled.
> > >
> > > Signed-off-by: Sergio Gonzalez Monroy
> > > <sergio.gonzalez.monroy@intel.com>
> > > ---
> > >  mk/rte.lib.mk      |  1 -
> > >  mk/rte.sharelib.mk | 12 +++++++++++-
> > [...]
> > > --- a/mk/rte.lib.mk
> > > +++ b/mk/rte.lib.mk
> > > @@ -63,7 +63,6 @@ ifeq ($(LINK_USING_CC),1)  # Override the
> > > definition of LD here, since we're linking with CC  LD := $(CC)
> > > LD_MULDEFS := $(call linkerprefix,-z$(comma)muldefs) -CPU_LDFLAGS :=
> > > $(call linkerprefix,$(CPU_LDFLAGS))  endif
> >
> > Why are you removing this line?
> 
Hi Thomas,

Basically the problem is when CPU_LDFLAGS has a value, which in the currently only happens if we set CPU_LDFLAGS in the command line or build i686 (setting CPU_LDFLAGS=-melf_i386).
In those cases, given the way the makefiles are being included, CPU_LDFLAGS is being 'linkerprefixed' twice, resulting in build error.
Removing that line avoided the second linker prefix of the CPU_LDFLAGS (note that we reset the original var instead of using a different var name).

There probably is a better way but I could not see an straightforward fix for it.
I planned to improve the current build system (already sent an RFC) and was waiting until 1.8 release to resume the work on it.

Thanks,
Sergio

> If it's really needed, it could be another patch.
> 
> > > --- a/mk/rte.sharelib.mk
> > > +++ b/mk/rte.sharelib.mk
> > [...]
> 
> Acked-by: Thomas Monjalon <thomas.monjalon@6wind.com>
> 
> Applied without the change to rte.lib.mk.
> 
> Thanks
> --
> Thomas