From mboxrd@z Thu Jan  1 00:00:00 1970
From: Adrien Mazarguil <adrien.mazarguil@6wind.com>
Subject: Re: [PATCH v2 4/4] ethdev: Add metadata flow and action
 items support
Date: Fri, 6 Apr 2018 14:20:12 +0200
Message-ID: <20180406122012.GQ4957@6wind.com>
References: <20180405135148.16388-1-declan.doherty@intel.com>
 <20180405135148.16388-5-declan.doherty@intel.com>
 <2392634.y0Dprd7BRi@xps>
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Cc: Declan Doherty <declan.doherty@intel.com>, dev@dpdk.org,
 Alex Rosenbaum <alexr@mellanox.com>, Ferruh Yigit <ferruh.yigit@intel.com>,
 Shahaf Shuler <shahafs@mellanox.com>, Qi Zhang <qi.z.zhang@intel.com>,
 Alejandro Lucero <alejandro.lucero@netronome.com>,
 Andrew Rybchenko <arybchenko@solarflare.com>,
 Mohammad Abdul Awal <mohammad.abdul.awal@intel.com>,
 Remy Horton <remy.horton@intel.com>,
 John McNamara <john.mcnamara@intel.com>, Rony Efraim <ronye@mellanox.com>,
 Jingjing Wu <jingjing.wu@intel.com>, Wenzhuo Lu <wenzhuo.lu@intel.com>,
 Yuanhan Liu <yliu@fridaylinux.org>,
 Bruce Richardson <bruce.richardson@intel.com>
To: Thomas Monjalon <thomas@monjalon.net>
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On Thu, Apr 05, 2018 at 06:49:32PM +0200, Thomas Monjalon wrote:
> 05/04/2018 15:51, Declan Doherty:
> > +struct rte_flow_item_metadata {
> > +       uint32_t id;            /**< field identifier */
> > +       uint32_t size;          /**< field size */
> > +       uint8_t bytes[];        /**< field value */
> > +};
> 
> Spotted C99 syntax of flexible array.
> Are we OK with all supported compilers?

I also thought they were a good idea at first but got rid of them in
rte_flow [1] for the following reasons:

- Not valid/standard C++.
- Can't be statically initialized.

Both can be overcome by relying on compiler extensions, however their use
should be restricted to a minimum in public APIs for portability reasons.

[1] http://dpdk.org/ml/archives/dev/2018-April/095307.html

-- 
Adrien Mazarguil
6WIND