[dpdk-dev] [PATCH v5 2/2] doc: add a guide doc for cross compiling from x86

[Gavin Hu]

Hi Jerin, Bruce and Thomas,

To fix the meson cross build issue(host clang + cross gcc), we have to decouple clang options from gcc ones.
Currently the options for gcc and clang tightly coupled as they share a single meson project and both added to the project arguments, this is the root cause.

I have a patch to remove the specific options from the project arguments and add it individually to C_FLAGS. It basically work, but it changed a lot of meson.build files.

Any comments are welcome.

Best Regards,
Gavin

> -----Original Message-----
> From: Gavin Hu
> Sent: Tuesday, June 12, 2018 9:28 AM
> To: 'Jerin Jacob' <jerin.jacob at caviumnetworks.com>
> Cc: Bruce Richardson <bruce.richardson at intel.com>; Thomas Monjalon
> <thomas at monjalon.net>; dev at dpdk.org; nd <nd at arm.com>
> Subject: RE: [dpdk-dev] [PATCH v5 2/2] doc: add a guide doc for cross
> compiling from x86
> 
> 
> 
> > -----Original Message-----
> > From: Jerin Jacob <jerin.jacob at caviumnetworks.com>
> > Sent: Monday, June 4, 2018 8:51 PM
> > To: Gavin Hu <Gavin.Hu at arm.com>
> > Cc: Bruce Richardson <bruce.richardson at intel.com>; Thomas Monjalon
> > <thomas at monjalon.net>; dev at dpdk.org
> > Subject: Re: [dpdk-dev] [PATCH v5 2/2] doc: add a guide doc for cross
> > compiling from x86
> >
> > -----Original Message-----
> > > Date: Mon, 4 Jun 2018 06:03:34 +0000
> > > From: Gavin Hu <Gavin.Hu at arm.com>
> > > To: Jerin Jacob <jerin.jacob at caviumnetworks.com>, Bruce Richardson
> > > <bruce.richardson at intel.com>, Thomas Monjalon
> <thomas at monjalon.net>
> > > CC: "dev at dpdk.org" <dev at dpdk.org>
> > > Subject: RE: [dpdk-dev] [PATCH v5 2/2] doc: add a guide doc for
> > > cross compiling from x86
> > >
> > > See my inline comments:
> > >
> > > > -----Original Message-----
> > > > From: Jerin Jacob <jerin.jacob at caviumnetworks.com>
> > > > Sent: Thursday, May 31, 2018 3:36 AM
> > > > To: Gavin Hu <Gavin.Hu at arm.com>
> > > > Cc: dev at dpdk.org
> > > > Subject: Re: [dpdk-dev] [PATCH v5 2/2] doc: add a guide doc for
> > > > cross compiling from x86
> > > >
> > > > -----Original Message-----
> > > > > Date: Tue, 29 May 2018 18:43:36 +0800
> > > > > From: Gavin Hu <gavin.hu at arm.com>
> > > > > To: dev at dpdk.org
> > > > > CC: gavin.hu at arm.com
> > > > > Subject: [dpdk-dev] [PATCH v5 2/2] doc: add a guide doc for
> > > > > cross compiling  from x86
> > > > > X-Mailer: git-send-email 2.1.4
> > > > >
> > > > > +   1. EXTRA_CFLAGS and EXTRA_LDFLAGS should be added to include
> > > > > + the
> > > > NUMA headers and link the library respectively,
> > > > > +   if the step
> > > > > + :ref:`argment_the_cross_toolcain_with_numa_support` was
> > > > skipped therefore the toolchain was not
> > > > > +   argmented with NUMA support.
> > > > > +
> > > > > +   2. RTE_DEVEL_BUILD has to be disabled, otherwise the numa.h
> > > > > + file gets
> > > >
> > > > If the warnings are from numa.h then please use -isystem <numa
> > > > install dir> instead of disabling RTE_DEVEL_BUILD.
> > > >
> > > [Gavin Hu] This is a good advice, I verified it okay and can upload
> > > a new
> > patch.
> > >
> > > > > +   a lot of compiling errors of Werror=cast-qual,
> > > > > + Werror=strict-prototypes
> > > > and Werror=old-style-definition.
> > > > > +   An example is given below:
> > > > > +
> > > > > +   .. code-block:: console
> > > > > +
> > > > > +      make -j CROSS=aarch64-linux-gnu- CONFIG_RTE_KNI_KMOD=n
> > > > CONFIG_RTE_EAL_IGB_UIO=n
> > > > > +      RTE_DEVEL_BUILD=n EXTRA_CFLAGS="-
> > I<numa_install_dir>/include"
> > > > EXTRA_LDFLAGS=
> > > > > +      "-L<numa_install_dir>/lib -lnuma"
> > > > > +
> > > >
> > > > As discussed earlier, meson cross build instruction is missing.
> > > >
> > > [Gavin Hu] I reproduced the meson build issue Bruce reported, as
> > > shown
> > below.
> > > It was not introduced by gcc, nor clang, it was actually introduced
> > > by meson.build, see line #65 of
> > > http://www.dpdk.org/browse/dpdk/tree/config/meson.build
> > > Even worse, "has_argument" is not reliable(refer here:
> > http://mesonbuild.com/Compiler-properties.html#has-argument) for
> some
> > compilers.
> > > This is the case of gcc and clang, which caused the 4 warning
> > > options were
> > included in the whole project, either the compiler is gcc or clang,
> > cross or native.
> > > This finally caused the unrecognized warning options.
> > >
> > > I tried to disable the warning options, then the compiling got lots
> > > of noisy
> > warnings and errors.
> > >
> > > To fix this issue, we need to create a meson subproject  for
> > > pmdinfogen,
> > the change is not little and I am not familiar with this.
> > >
> > > Any comments are welcome!
> >
> >
> > If I am not wrong, This is specific to host compiler issue with specific
> version.
> > Right? The build steps will remain same, so as far as this patch
> > concerned, you can add the meson build step in this patch.
> >
> [Gavin Hu] Hi Jerin,
> Sorry for late response, but I am still keeping working on that(some more
> patches are in process of internal review).
> The host compiler issue with specific version was fixed by one of my patch.
> 
> With all my patches applied:
> For GNU Makefile,
> 1. Host clang + cross gcc works
> 2. Host gcc + cross gcc works
> 
> For Meson/Ninja:
> 3. Host gcc + cross gcc works
> 4. Host clang + cross gcc does NOT work
> 
> The root cause of number 4  is clear, it is a meson build project issue.
> Both gcc and clang take all the 4 project arguments, but can NOT recognize
> this one: warning option '-Wno-format-truncation'
> For more details , please have a look at line #56~#67 of this file:
> http://www.dpdk.org/browse/dpdk/tree/config/meson.build
> http://mesonbuild.com/Compiler-properties.html#has-argument
> 
> The compiling error:
> clang  -Ibuildtools/pmdinfogen/pmdinfogen at exe -Ibuildtools/pmdinfogen -
> I../buildtools/pmdinfogen -Iconfig -I../config -I. -I../ -
> Ilib/librte_eal/common/include/arch/arm -
> I../lib/librte_eal/common/include/arch/arm -Ilib/librte_eal/common/include
> -I../lib/librte_eal/common/include -Ilib/librte_eal/common -
> I../lib/librte_eal/common -Ilib/librte_eal/linuxapp/eal/../../../librte_compat -
> I../lib/librte_eal/linuxapp/eal/../../../librte_compat -
> I../lib/librte_eal/linuxapp/eal/include -
> Ibuildtools/pmdinfogen/../../lib/librte_pci -
> I../buildtools/pmdinfogen/../../lib/librte_pci -Xclang -fcolor-diagnostics -pipe
> -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -Werror -O3 -include
> rte_config.h -Wsign-compare -Wcast-qual -Wno-address-of-packed-member
> -Wno-format-truncation -MD -MQ
> 'buildtools/pmdinfogen/pmdinfogen at exe/pmdinfogen.c.o' -MF
> 'buildtools/pmdinfogen/pmdinfogen at exe/pmdinfogen.c.o.d' -o
> 'buildtools/pmdinfogen/pmdinfogen at exe/pmdinfogen.c.o' -
> c ../buildtools/pmdinfogen/pmdinfogen.c
> error: unknown warning option '-Wno-format-truncation' [-Werror,-
> Wunknown-warning-option]
> [265/1011] Compiling C object
> 'lib/rte_pipeline at sta/librte_pipeline_rte_table_action.c.o'.
> 
> Best Regards,
> Gavin
> 
> 
> 
> 
> 
> > >
> > > [265/893] Compiling C object
> > 'buildtools/pmdinfogen/pmdinfogen at exe/pmdinfogen.c.o'.
> > > warning: unknown warning option '-Wno-format-truncation'
> > > [-Wunknown-warning-option]
> > > 1 warning generated.
> > >
> > > >
> > > > > diff --git a/doc/guides/linux_gsg/index.rst
> > > > > b/doc/guides/linux_gsg/index.rst index 2a7bdfe..077f930 100644
> > > > > --- a/doc/guides/linux_gsg/index.rst
> > > > > +++ b/doc/guides/linux_gsg/index.rst
> > > > > @@ -13,6 +13,7 @@ Getting Started Guide for Linux
> > > > >      intro
> > > > >      sys_reqs
> > > > >      build_dpdk
> > > > > +    cross_build_dpdk_for_arm64
> > > > >      linux_drivers
> > > > >      build_sample_apps
> > > > >      enable_func
> > > > > --
> > > > > 2.1.4
> > > > >