DUB build questions

[Russel Winder via Digitalmars-d-learn]

On Sat, 2014-12-20 at 05:46 +0000, Dicebot via Digitalmars-d-learn wrote:
> On Saturday, 20 December 2014 at 04:15:00 UTC, Rikki Cattermole 
> wrote:
> > > b) Can I do parallel builds with dub. CMake gives me Makefiles 
> > > so I can
> > > make -j does dub have a similar option?
> > 
> > No
> 
> Worth noting that it is not actually a dub problem as much, it is 
> simply not worth adding parallel builds because separate
> compilation is much much slower with existing D front-end 
> implementation and even doing it in parallel is sub-optimal
> compared to "dump-it-all-at-once".

>From previous rounds of this sort of question (for the SCons D 
tooling), the consensus of the community appeared to be that the only 
time separate module compilation was really useful was for mixed D, C, 
C++, Fortran systems. For pure D systems, single call of the compiler 
is deemed far better than traditional C, C++, Fortran compilation 
strategy. This means the whole "make -j" thing is not an issue, it 
just means that Dub is only really dealing with the "all D" situation.

The corollary to this is that DMD, LDC and GDC really need to make use 
of all parallelism they can, which I suspect is more or less none.

Chapel has also gone the "compile all modules with a single compiler 
call" strategy as this enables global optimization from source to 
executable.
  
-- 
Russel.
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