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From: Thomas Monjalon <thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>
To: "Qiu,
	Michael" <michael.qiu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
	dev-VfR2kkLFssw@public.gmane.org
Subject: Re: [PATCH v3] test-pmd: Fix pointer aliasing error
Date: Thu, 11 Dec 2014 01:54:21 +0100	[thread overview]
Message-ID: <1930269.B5nWyJ5DBl@xps13> (raw)
In-Reply-To: <533710CFB86FA344BFBF2D6802E60286C9D683-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>

> > app/test-pmd/csumonly.c: In function ‘get_psd_sum’:
> > build/include/rte_ip.h:161: error: dereferencing pointer ‘u16’
> >         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-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> > ---
> > v3 --> v2:
> > 	use uintptr_t instead of unsigned long to
> > 	save pointer.
> >
> > v2 --> v1:
> > 	Workaround solution instead of shut off the
> > 	gcc params.
> 
> This workaround is to solve the compile issue of GCC strict-aliasing(Two
> different type pointers should not be point to the same memory address).
> 
> For GCC 4.4.7 it will definitely occurs if  flags "-fstrict-aliasing"
> and "-Wall" used.

Acked-by: Thomas Monjalon <thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>> 

Applied with a comment in the code.

Thanks
-- 
Thomas

  parent reply	other threads:[~2014-12-11  0:54 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1417606044-3432-1-git-send-email-michael.qiu@intel.com>
     [not found] ` <1417606099-3489-1-git-send-email-michael.qiu@intel.com>
     [not found]   ` <1417606099-3489-1-git-send-email-michael.qiu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
2014-12-03 11:42     ` [PATCH] test-pmd: Fix pointer aliasing error Bruce Richardson
2014-12-03 13:59       ` Qiu, Michael
     [not found]         ` <533710CFB86FA344BFBF2D6802E60286C9C531-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2014-12-03 14:51           ` Bruce Richardson
2014-12-03 15:19             ` Qiu, Michael
     [not found]               ` <533710CFB86FA344BFBF2D6802E60286C9C5BA-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2014-12-03 15:36                 ` Bruce Richardson
2014-12-04  2:38                   ` Qiu, Michael
     [not found]                     ` <533710CFB86FA344BFBF2D6802E60286C9C893-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2014-12-04  3:28                       ` [PATCH v2] " Michael Qiu
     [not found]                         ` <1417663711-19576-1-git-send-email-michael.qiu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
2014-12-04  4:16                           ` [PATCH v3] " Michael Qiu
2014-12-05  5:34                             ` Qiu, Michael
     [not found]                               ` <533710CFB86FA344BFBF2D6802E60286C9CFE5-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2014-12-05  9:24                                 ` Thomas Monjalon
2014-12-08  1:28                                   ` Qiu, Michael
2014-12-08  1:30                             ` Qiu, Michael
2014-12-10  3:44                               ` Qiu, Michael
     [not found]                               ` <533710CFB86FA344BFBF2D6802E60286C9D683-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2014-12-11  0:54                                 ` Thomas Monjalon [this message]
2014-12-11 17:51                                   ` r k
2014-12-12  6:49                                     ` Qiu, Michael
2014-12-04 12:54                           ` [PATCH v2] " Ananyev, Konstantin
2014-12-03 15:24       ` [PATCH] " Olivier MATZ
     [not found]         ` <547F2B37.5060500-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>
2014-12-03 16:03           ` Dayu Qiu
2014-12-03 15:57       ` Dayu Qiu
2014-12-03 16:26 ` [PATCH] test-pmd: Fix "__BYTE_ORDER__" not defined error Qiu, Michael
     [not found]   ` <533710CFB86FA344BFBF2D6802E60286C9C636-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2014-12-03 19:59     ` Thomas Monjalon
2014-12-03 20:47       ` [PATCH 0/2] fix endianness in EAL Thomas Monjalon
     [not found]         ` <1417639668-23500-1-git-send-email-thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>
2014-12-03 20:47           ` [PATCH 1/2] eal: detect endianness Thomas Monjalon
2014-12-04  2:28             ` Qiu, Michael
     [not found]               ` <533710CFB86FA344BFBF2D6802E60286C9C86D-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2014-12-04  9:00                 ` Thomas Monjalon
2014-12-04 10:28                   ` Qiu, Michael
     [not found]                     ` <533710CFB86FA344BFBF2D6802E60286C9CB38-0J0gbvR4kThpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2014-12-04 12:19                       ` Thomas Monjalon
2014-12-04 12:50                         ` Qiu, Michael
2014-12-03 20:47           ` [PATCH 2/2] app/testpmd: fix endianness detection Thomas Monjalon
2014-12-04  9:28           ` [PATCH 0/2] fix endianness in EAL Chao Zhu
     [not found]             ` <54802955.2090104-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
2014-12-05 16:01               ` Thomas Monjalon

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