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From: Thomas Monjalon <thomas.monjalon@6wind.com>
To: "Qiu, Michael" <michael.qiu@intel.com>, dev@dpdk.org
Date: Thu, 11 Dec 2014 01:54:21 +0100
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Subject: Re: [dpdk-dev] [PATCH v3] test-pmd: Fix pointer aliasing error
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> > app/test-pmd/csumonly.c: In function =E2=80=98get_psd_sum=E2=80=99:=

> > build/include/rte_ip.h:161: error: dereferencing pointer =E2=80=98u=
16=E2=80=99
> >         does break strict-aliasing rules
> > build/include/rte_ip.h:157: note: initialized from here
> >         ...
> >
> > The root cause is that, compile enable strict aliasing by default,
> > while in function rte_raw_cksum() try to convert 'const char *'
> > to 'const uint16_t *'.
> >
> > This patch is one workaround fix.
> >
> > Signed-off-by: Michael Qiu <michael.qiu@intel.com>
> > ---
> > v3 --> v2:
> > =09use uintptr_t instead of unsigned long to
> > =09save pointer.
> >
> > v2 --> v1:
> > =09Workaround solution instead of shut off the
> > =09gcc params.
>=20
> This workaround is to solve the compile issue of GCC strict-aliasing(=
Two
> different type pointers should not be point to the same memory addres=
s).
>=20
> For GCC 4.4.7 it will definitely occurs if  flags "-fstrict-aliasing"=

> and "-Wall" used.

Acked-by: Thomas Monjalon <thomas.monjalon@6wind.com>>=20

Applied with a comment in the code.

Thanks
--=20
Thomas