This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Fwd: C++ PATCH: PR 20599 (1/3)


On 19/09/06, Doug Gregor <doug.gregor@gmail.com> wrote:
I don't think this made it to the list...

---------- Forwarded message ----------
From: Doug Gregor <doug.gregor@gmail.com>
Date: Sep 19, 2006 10:34 AM
Subject: Re: C++ PATCH: PR 20599 (1/3)
To: Gennaro Prota <gennaro_prota@yahoo.com>
Cc: gcc-patches@gcc.gnu.org, libstdc++@gcc.gnu.org


On 9/19/06, Gennaro Prota <gennaro_prota@yahoo.com> wrote:


>
 On Mon, 18 Sep 2006 19:27:09 -0400, "Doug Gregor"
>GCC could break this stale-mate by including experimental
>implementations of these features. Then, the community at large can
>experiment and better understand these features, finding (and fixing!)
>problems before the ink dries on C++0x.

I mostly agree without your analysis. But I think it also matters
having a relatively long period of experimentation.

 I don't think it's the length of time for experimentation, but the
amount of time spent in aggregate. If 100 people play with the feature
for 2-3 hours, we'll get a much better sense of its capabilities and
limitations than if one person spends 300 hours using that feature.
It's extremely hard to get people to download and install a new
compiler to try out a language feature. I've found this with
ConceptGCC: each time I give a talk or a demonstration, people would
come up to me and say how much they want to have this feature in their
compiler. But few... very few... actually go download the compiler to
try it. The barrier of installing a new compiler is just to high. But
if they could just flip a switch in their current compiler, they will
try it.

Connected to this, being on a branch means very little exposure (I have contributed to libstdc++, yet managed to miss for a long time that I ConceptGCC was available).

Perhaps the flag to enable the features should be something like
-UNSTABLE_c++0x? That is very ugly looking, but surely that is partly
the point, and it should be clear it will be removed later.

What I would personally like to see would be the ability to enable
these flags for certain headers. I'm not sure if this is feasable, but
I imagine it would be of benefit both to g++ and to the features
themselves if libstdc++ can start using them as soon as possible.

Chris


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]