phc-discussions - Re: [PHC] C99 in reference implementations

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Message-ID: <52069E10.4080902@dei.uc.pt>
Date: Sat, 10 Aug 2013 21:09:52 +0100
From: Samuel Neves <sneves@....uc.pt>
To: discussions@...sword-hashing.net
CC: Daniel Franke <dfoxfranke@...il.com>
Subject: Re: [PHC] C99 in reference implementations

On 10-08-2013 18:45, Daniel Franke wrote:
> I have a reference implementation of a prospective PHC entry written in
> "portable" C99. By "portable", I mean that it uses only standard C99
> language features, has no external library dependencies, and should
> produce identical output regardless of host CPU architecture. However,
> it makes extensive use of C99 language features, including
> <stdint.h>/<stdbool.h>, mixed declarations and code, and variable-length
> arrays. Taking advantage of these features significantly improves
> readability, but will prevent the code from compiling on MSVC and any
> other compilers with poor C99 support. Does/should this pass muster for
> PHC submission requirements?
>

During the competition I don't think this is a problem, particularly for
a reference implementation that is meant to be readable. The call for
submissions asks for a Makefile with appropriate build instructions, so
making sure you pass -std=c99 should be enough.

That said, if your submission wins, there will be a number of people
adapting that code to run in whatever platform and compiler version they
favor or are forced to use. By then, there probably should be a more
"portable" implementation. I think the only contentious feature is VLAs,
since the other two can be worked around more or less easily.