Re: [dpdk-dev] [PATCH v6 2/5] build: use dependency() instead of find_library()

[Thomas Monjalon <thomas@monjalon.net>]

12/02/2019 16:03, Bruce Richardson:
> On Tue, Feb 12, 2019 at 03:47:56PM +0100, Thomas Monjalon wrote:
> > 12/02/2019 12:43, Bruce Richardson:
> > > On Tue, Feb 12, 2019 at 12:36:17PM +0100, Thomas Monjalon wrote:
> > > > 12/02/2019 12:31, Bruce Richardson:
> > > > > On Tue, Feb 12, 2019 at 12:15:43PM +0100, Thomas Monjalon wrote:
> > > > > > 06/02/2019 18:08, Luca Boccassi:
> > > > > > > Whenever possible (if the library ships a pkg-config file) use meson's
> > > > > > > dependency() function to look for it, as it will automatically add it
> > > > > > > to the Requires.private list if needed, to allow for static builds to
> > > > > > > succeed for reverse dependencies of DPDK. Otherwise the recursive
> > > > > > > dependencies are not parsed, and users doing static builds have to
> > > > > > > resolve them manually by themselves.
> > > > > > > When using this API avoid additional checks that are superfluous and
> > > > > > > take extra time, and avoid adding the linker flag manually which causes
> > > > > > > it to be duplicated.
> > > > > > > 
> > > > > > > Signed-off-by: Luca Boccassi <bluca@debian.org>
> > > > > > > Acked-by: Bruce Richardson <bruce.richardson@intel.com>
> > > > > > 
> > > > > > This patch breaks compilation on my machine with a lot of strange errors:
> > > > > > 
> > > > > > from drivers/net/pcap/rte_eth_pcap.c
> > > > > > 
> > > > > > /usr/include/stdint.h:109: error: "__INT64_C" redefined
> > > > > > /usr/include/bits/stdlib-bsearch.h:32:13: error: cast discards 'const' qualifier from pointer target type
> > > > > > /usr/include/pthread.h:682:6: error: 'regparm' attribute directive ignored
> > > > > > etc
> > > > > >
> > > > > Is this on Arch linux again? I just reverified these first two patches and
> > > > > they work fine for me on Fedora (I assume Luca probably tested them already on
> > > > > Debian) 
> > > > > 
> > > > > Anything unusual about your setup?
> > > > 
> > > > Nothing unusual. Just using the best environment ever ;)
> > > > I will try to debug it.
> > > > 
> > > It may be something pcap-specific, since pcap has to have it's own special
> > > query mechanims outside the normal pkg-config one. If you remove the
> > > pcap-driver changes, does the rest of the patch work for you?
> > 
> > Yes, the issue happens only with pcap on Arm.
> > Reverting the pcap related changes, it builds fine.
> > 
> > More infos about my setup:
> > 	meson-0.49.1
> > 	aarch64-linux-gnu-gcc-8.2.0
> > 	libpcap-1.9.0 (32 and 64-bit) for x86
> > 
> > I think there is a mix between libcap for x86 and Arm compilation.
> > Probably a meson bug?
> > 
> Could well be a meson issue. It may be using the local pcap-config rather
> than the cross-compilation version [assuming cross-compilation here, though
> I don't see the issue with my setup].
> 
> Thomas, can you apply this set with the pcap driver change dropped,
> or is it better if Luca does a new version of this set?

I think we need a comment about the pcap miss.
Probably better to do a new version.

Luca, please could you test cross-compilation?