From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kevin Traynor <ktraynor@redhat.com>
Subject: Re: [PATCH] meson: fix compilation with binutils version
 2.30
Date: Wed, 6 Feb 2019 16:16:55 +0000
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References: <20190117171744.63455-1-harry.van.haaren@intel.com>
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Cc: ferruh.yigit@intel.com, bruce.richardson@intel.com, thomas@monjalon.net
To: Harry van Haaren <harry.van.haaren@intel.com>, dev@dpdk.org
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On 01/17/2019 05:17 PM, Harry van Haaren wrote:
> This commit reworks the checks for binutils 2.30 and how
> the flags to disable AVX512F are passed to the compiler.
> 
> Previously the #define for including AVX512 code was set,
> while the -mno-avx512f argument was given to the compiler.
> This would cause gcc to correctly refuse to emit AVX512
> instructions, but the rte_memcpy code that includes AVX512
> optimizations was being added to the build.
> 
> The check for binutils check is now moved to x86 as it is
> irrelevant for other architectures, and the -mno-avx512f
> flag is passed to a march_opts array in meson. As the
> -mno-avx512 flag is added earlier in the build, the code
> in rte_memcpy is no longer attempted to be compiled.
> 
> This commit also adds a message print in the meson configure
> stage to alert the user of the workaround being employed.
> 
> Fixes: a32ca9a4ebc1 ("mk: fix scope of disabling AVX512F support")
> 

The patch this fixes is queued for 18.11 stable, so I presume this
should go there as well. I will send it as part of the normal queued
email anyway, so please let me know if there's a reason not to backport.

> Signed-off-by: Harry van Haaren <harry.van.haaren@intel.com>
> 
> ---