druntime

[Jonathan M Davis]

On 2011-07-08 15:23, Brad Roberts wrote:
> On Fri, 8 Jul 2011, Iain Buclaw wrote:
> > == Quote from Jonathan M Davis (jmdavisProg at gmx.com)'s article
> > 
> > > On 2011-07-08 10:42, bioinfornatics wrote:
> > > > @sean
> > > > if you install ldc2 like:
> > > > $ cmake . -DD_VERSION:STRING=2 -DCONF_INST_DIR:PATH=/etc
> > > > $ make -j4 VERBOSE=2
> > > > $ make -j4 install
> > > > 
> > > > and try install druntime from
> > > > https://github.com/D-Programming-Language/druntime.git I can't
> > > > because make file is only for dmd. What i try to said, yes we need 1
> > > > druntime so for this reason druntime installer need support at least
> > > > dmd, ldc, gdc. But is not case currently. And for this reason d2
> > > > can't go to Fedora 16. Because ldc2 use cmake for build 3 projects
> > > > (ldc, druntime, phobos) I need 3 installer separately. And ldc2 use
> > > > a druntime fork!
> > > > 
> > > > thanks for any answer :-)
> > > 
> > > I believe that it's _expected_ that other compilers will use forks of
> > > druntime. They may have to make changes to druntime to work, and Sean
> > > doesn't want to have to maintain all of the differences for every
> > > compiler. Rather, druntime is the reference implementation intended
> > > for dmd, and other compiler maintainers do whatever they need to with
> > > their own version of it to get it work with their compiler.
> > > - Jonathan M Davis
> > 
> > Exactly this, and the case is also vice versa with gdc. The druntime
> > reference library also does many things that are unreasonable and
> > incompatible with gdc (and I assume ditto ldc too).
> > 
> > One future plan on my list is the restructuring of core/stdc to be more
> > ports friendly (the source, not the installed files) - something to help
> > push along ARM development for D2 with GDC, and hopefully for other
> > archs to follow pursuit. The result being one elongated patch that won't
> > be accepted upstream for sure. :~)
> > 
> > Regards
> > Iain
> 
> This is one area that I disagree with Sean on. I think it's worth merging
> in as much as we can to the druntime code base. I'm not against having
> separate trees vended by each compiler, but I hope/expect those to be the
> lowest level details and not be detectably different from phobos or user
> code. Having core.stdc diverge, as just one example, is a recipe for
> having code that only works on top of one specific runtime, which is NOT
> what we want.
> 
> I _do_ want druntime to support more compilers than dmd an dmore platforms
> than dmd supports.

Well, I think that it makes sense to try and minimize what needs to be 
different between compilers, but it does risk being messy if we try and 
support the quirks of multiple compilers in the main druntime repository. And 
it's not like we're going to have the autotester dealing with all of that 
either. We need to try and minimize what needs to be changed between compilers 
in order to minimize the work for people porting druntime to other compilers 
and minimize the risk of code breakage due to those changes, but I'm highly 
skeptical that having druntime worry about multiple compilers is a good idea.

- Jonathan M Davis