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Date: Wed, 17 Jan 2024 10:52:40 +0300
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Subject: Re: [PATCH v3 5/5] eal: replace out of bounds VLA with static_assert
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To: Stephen Hemminger <stephen@networkplumber.org>, dev@dpdk.org
Cc: =?UTF-8?Q?Morten_Br=C3=B8rup?= <mb@smartsharesystems.com>,
 Tyler Retzlaff <roretzla@linux.microsoft.com>
References: <20231111172153.57461-1-stephen@networkplumber.org>
 <20240116184307.162882-1-stephen@networkplumber.org>
 <20240116184307.162882-6-stephen@networkplumber.org>
From: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Organization: OKTET Labs
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On 1/16/24 21:41, Stephen Hemminger wrote:
> Both Gcc, clang and MSVC have better way to do compile time
> assertions rather than using out of bounds array access.
> The old method would fail if -Wvla is enabled because compiler
> can't determine size in that code.  Also, the use of new
> _Static_assert will catch broken code that is passing non-constant
> expression to RTE_BUILD_BUG_ON().
> 
> Need to add brackets {} around the static_assert() to workaround
> a bug in clang. Clang was not handling static_assert() in
> a switch case properly.
> 
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> Acked-by: Morten Brørup <mb@smartsharesystems.com>
> Acked-by: Tyler Retzlaff <roretzla@linux.microsoft.com>

Acked-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>

Does it imply any limitations on Gcc / Clang versions to
be used? Is it documented somewhere in DPDK?