From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: [PATCH] eal/x86: fix clang build with -O0
Date: Fri, 03 Jun 2016 10:46:44 +0200
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Cc: Olivier MATZ <olivier.matz@6wind.com>, Damjan Marion <damarion@cisco.com>
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2016-06-03 10:16, Olivier MATZ:
> On 06/03/2016 10:15 AM, Thomas Monjalon wrote:
> > From: Damjan Marion <damarion@cisco.com>
> > 
> > Clang seems to have a bug with asm inside inline function rte_xabort():
> > 
> > rte_rtm.h:56:15: error: invalid operand for inline asm constraint 'i'
> >         asm volatile(".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory");
> >                      ^
> > 
> > It is seen only when building with EXTRA_CFLAGS=-O0.
> > 
> > The workaround is to replace the inline function by a macro.
> > 
> > Fixes: ba7468997ea6 ("spinlock: add HTM lock elision for x86")
> > 
> > Signed-off-by: Damjan Marion <damarion@cisco.com>
> > Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
> 
> Generally speaking, it's not a good idea to replace a static inline by a
> macro because it relaxes type checking. Looks ok in that case to
> workaround the clang issue.
> 
> Acked-by: Olivier Matz <olivier.matz@6wind.com>

Thanks,
This patch has been appplied very quickly for the purpose of a live demo
at a VPP event: https://wiki.fd.io/view/Events