[wwwdocs] RFC - mention Cilk Plus in the GCC 4.9 release notes

[Andi Kleen]

Andi Kleen <andi@firstfloor.org> writes:

> "Iyer, Balaji V" <balaji.v.iyer@intel.com> writes:
>>
>> The sentence "Current only..." should be changed to something like this:
>>
>> Currently all the features except _Cilk_for has been implemented.
>
> It would be also good if the documentation mentioned that you have to
> specify -lcilkrts

Also it would be good to specify exactly what parts of Cilk are
supported currently. It's some what hard to figure out.

One trap I ran into (perhaps naively) is that I tried to use 
cilk_spawn (as documented in some tutorials) instead of _Cilk_spawn 

-Andi