From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH] eal: remove variable length array
Date: Wed, 19 Dec 2018 22:45:58 +0100
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References: <20181214163827.9403-1-jeffrey.b.shaw@intel.com>
 <20181214190713.GB9964@ae13-28.jf.intel.com>
 <3a573b56-6ea0-812c-4641-830fbd3c59cc@ericsson.com>
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Cc: dev@dpdk.org, Jeff Shaw <jeffrey.b.shaw@intel.com>,
 stephen@networkplumber.org, harini.ramakrishnan@microsoft.com
To: Mattias =?ISO-8859-1?Q?R=F6nnblom?= <mattias.ronnblom@ericsson.com>,
 Jason Messer <jmesser@microsoft.com>
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14/12/2018 21:28, Mattias R=C3=B6nnblom:
> On 2018-12-14 20:07, Jeff Shaw wrote:
> >>> The code prior to this commit produced the following warning when
> >>> compiled with "-Wvla -std=3Dc90".
> >>>
> >>>     warning: ISO C90 forbids variable length array =E2=80=98array=E2=
=80=99 [-Wvla]
> >>>
> >>> This commit removes the variable length array from the PMD debug
> >>> trace function by allocating memory dynamically on the stack using
> >>> alloca().
> >>
> >> Is alloca() even included in *any* C standard? As far as I see, it just
> >> achieves the same thing in an uglier, less portable way than VLAs.
> >=20
> > I agree that it is much less elegant than a VLA. This is in preparation
> > for DPDK on Windows, which using the Microsoft Visual C++ (MSVC) compil=
er.
> > MSVC does not support variable length arrays. It does, however, support
> > alloca(), as does GCC/ICC.
> >=20
> > For this particular instance, the point is moot, since the function is
> > not used anywhere and can just as easily be removed. Though it does not
> > address the issue for the ~100 other instances where VLAs are used. We
> > will be submitting patches for those as more common files are ported to
> > Windows.
>=20
> If Microsoft's C compiler doesn't support C99, some 20 years after its=20
> release, maybe it's time to find a new compiler, instead of messing up=20
> the DPDK code in a ~100 instances.

If think there is no reasonnable compiler for Windows.
Yes I know, it's crazy.

Microsoft, should we wait 10 more years to have C99 supported in MSVC?