Re: [lwip-devel] byte order, packing, optimizations

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Stéphane Lesage wrote:
> Well, I recently documented that on the wiki, but there is still no
> documentation for checksum/byte swapping in doc/sys_arch.txt.
>    
Yeah, that could be improved, but I'm an opponent of adding warnings 
where we only give a hint to optimization: the code as it is works 
perfectly well - on platforms where performance isn't the main goal, 
there's no need to issue a warning! Also, not everyone has the 
possibility to generate a LWIP_PLATFORM_BYTESWAP macro that is really 
faster than the default C code we have.
> Can we also create a new cc.txt file to separate processor architecture
> and OS ?
>    
Feel free to post your proposals!
> BTW, I'll add something about set_errno on the wiki.
>    
About set_errno? What?
> These warnings are output only once, so it's not so annoying...
>    
That depends on whether the developer changes something or not. If he 
decides he is OK with the current status, the warning will be shown with 
every compilation and warnings==errors doesn't work.
> What do you think about choosing checksum algo 2 as default ?
>    
I'm OK with that. But people shouldn't rely on that as it's a very 
crucial function regarding performance and on most platforms can be 
improved by writing an assembler version.

Simon