Re: [RFC] Switching implementation language to C++

[Toon Moene <toon at moene dot org>]

On 05/31/2010 06:22 PM, Diego Novillo wrote:

> Now that the SC and the FSF have agreed to this, we should decide
> whether we switch and how. So, I would like comments on the following
> questions:

Hmmmm, when I voted "yes" on the question "Requiring C++ Compiler for 
GCC Builds" (that was the subject of the mail to the Steering Committee 
mailing list to discuss this), I had the following in mind:

> 1- Should we switch to C++?

Yes, otherwise I wouldn't have taken the time to ponder this.  In fact, 
if not for the hordes of people that are only too eager to use every 
nook and cranny of the C++ language, I would have been much more 
supportive, as the situation we're finding ourselves in today is as if 
we were to write a Fortran 2003 compiler using only features from 
Fortran 77 plus (DE)ALLOCATE.

This simply isn't leading us into a maintainable future.

> 2- What is the cost in terms of build time?

Vladimir Makarov already addressed this.

> 3- What coding guidelines should we use?

We might need some time to find the right coding standards for *our* use.

What I wrote in my e-mail to the SC mailing list to support my stance 
was the following:

"The useful part is to be able to use stl data structures and functions 
to do the hard work in the compiler instead of using specially-written 
tree-, list-, bitmap-, queue- and stack-creators, destroyers and walkers."

because I think that would be *immediately* useful, as in ...

> 4- Should we make the switch during the 4.6 stage 1?

... version 4.6.

Of course I agree with Richard Guenther that - *if done well and 
completely* - turning the tree data type into a class is desirable.

However, that might simply be too much for the approximately 6 months 
remaining of 4.6's stage 1.

Cheers,

--
Toon Moene - e-mail: toon@moene.org - phone: +31 346 214290
Saturnushof 14, 3738 XG  Maartensdijk, The Netherlands
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