Re: Switching to C++ by default in 4.8

[Lawrence Crowl <crowl at google dot com>]

On 4/4/12, Richard Guenther <richard.guenther@gmail.com> wrote:
> On Apr 4, 2012 Bernd Schmidt <bernds@codesourcery.com> wrote:
> > On 04/04/2012 11:06 AM, Richard Guenther wrote:
> > > So - I'll veto the switch unless I see 1) and 2).  1) and 2)
> > > can be combined by transitioning vec.h to a C++ template class,
> > > with proper GC support.  (not sure that I can veto anything
> > > - heh)
> >
> > I don't think I can veto anything, but I'll go on the record
> > again saying that I don't think this entire plan is a good
> > idea. Write a new project in C++? Absolutely. Convert a large
> > existing one to a different language? A huge waste of time that
> > will distract us for years from actual user-visible changes.
>
> I agree for the idea of converting all of GCC to C++ (whatever
> that means).  I disagree for the part making the internal
> infrastructure easier to use, understand and maintain.  Which
> means targeting mostly isolated sub-systems, like vec.h (and
> other various containers), double-int.[ch] (and other various
> way of representing and working with constants).  Making tree
> or gimple a C++ class with inheritance and whatever is indeed
> a huge waste of time and existing developer ressources (that,
> if only because they have to adapt and maintain two completely
> different code-bases over some time).

Trees are presently a significant problem in that many static errors
become dynamic errors, which entails more debugging.

> I expect the GCC core to maintain written in C, compiled by C++.

Converting VECs to C++ vectors vector would provide significant code
clarity benefits.  The files in which that is done would necessarily
be C++ only.

> > I also find debugging C++ in gdb somewhat more annoying than
> > debugging plain C, and at the moment I always go back to a
> > stage1 compiler.
>
> Indeed - I'd be worried if my debugging efficiency decreases by
> more than 5%.

If the number of debugging sessions was reduced by the same amount,
the result would be a net wash.

-- 
Lawrence Crowl