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To: Jeff Shaw <jeffrey.b.shaw@intel.com>, dev@dpdk.org
References: <20181214163827.9403-1-jeffrey.b.shaw@intel.com>
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Subject: Re: [dpdk-dev] [PATCH] eal: remove variable length array
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On 2018-12-14 17:38, Jeff Shaw wrote:
> Compilers that do not support the C11 standard, or do not implement
> gcc extensions, may not support variable length arrays.
> 

VLAs are a C99 thing.

> The code prior to this commit produced the following warning when
> compiled with "-Wvla -std=c90".
> 
>    warning: ISO C90 forbids variable length array ‘array’ [-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.