Re: [dpdk-stable] [dpdk-dev] [PATCH] mk: fix lib filtering

[Bruce Richardson <bruce.richardson@intel.com>]

On Thu, Apr 06, 2017 at 04:48:11PM +0200, Thomas Monjalon wrote:
> 2017-04-06 16:14, Olivier Matz:
> > I get the following error when linking the test application:
> >   build/lib/librte_pmd_thunderx_nicvf.a(nicvf_hw.o):
> >   In function `nicvf_qsize_regbit':
> >   drivers/net/thunderx/base/nicvf_hw.c:451: undefined reference to `log2'
> >   build/lib/librte_pmd_thunderx_nicvf.a(nicvf_hw.o):
> >   In function `nicvf_rss_reta_update':
> >   drivers/net/thunderx/base/nicvf_hw.c:804: undefined reference to `log2'
> >   build/lib/librte_pmd_thunderx_nicvf.a(nicvf_hw.o):
> >   In function `nicvf_rss_reta_query':
> >   drivers/net/thunderx/base/nicvf_hw.c:825: undefined reference to `log2'
> > 
> > While I don't know why it does not happen for a default build, the error
> > can be explained. The link command line is:
> > 
> >    gcc -o test ... *.o ... -Wl,-lm ... -Wl,-lrte_pmd_thunderx_nicvf ...
> > 
> > rte_pmd_thunderx_nicvf needs the math library, and it should be
> > added after. This is not the case because the test application also
> > adds the math library.
> > 
> > The makefile already filters the libraries, but it keeps the first
> > occurrence of the lib. Instead, the last one should be kept.
> > 
> > Fixes: edf4d331dcdb ("mk: eliminate duplicates from libraries list")
> > 
> > Cc: stable@dpdk.org
> > Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
> 
> Acked-by: Thomas Monjalon <thomas.monjalon@6wind.com>
> 
> It is a really nice Makefile recursive function :)
> 

"nice Makefile recursive function"

I recognise those words individually, but having them together just
doesn't make any sense :-)