From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bruce Richardson <bruce.richardson@intel.com>
Subject: Re: [PATCH] ring: fix build with icc
Date: Wed, 5 Apr 2017 16:56:52 +0100
Message-ID: <20170405155652.GA15156@bricha3-MOBL3.ger.corp.intel.com>
References: <20170405150312.20960-1-ferruh.yigit@intel.com>
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Cc: Ferruh Yigit <ferruh.yigit@intel.com>, dev@dpdk.org
To: Thomas Monjalon <thomas.monjalon@6wind.com>
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On Wed, Apr 05, 2017 at 05:29:48PM +0200, Thomas Monjalon wrote:
> 2017-04-05 16:03, Ferruh Yigit:
> > build error:
> > In file included from .../lib/librte_ring/rte_ring.c(90):
> > .../lib/librte_ring/rte_ring.h(162):
> > error #1366: a reduction in alignment without the "packed" attribute
> > is ignored
> >   } __rte_cache_aligned;
> >       ^
> > 
> > Alignment attribute moved to first element of the struct
> 
> The fix is surprising.
> Is it really doing the same thing as
> 	} __rte_cache_aligned;
> at the end of the struct?
> 
It should be. Aligning the whole structure to start on a cache-line
boundary should be exactly the same as telling the compiler to put
the first field of the structure on a cacheline boundary.

/Bruce