On Saturday, 20 December 2014 at 08:36:15 UTC, Russel Winder via
Digitalmars-d-learn wrote:
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.
Thanks for the info everyone.
I've used dub for just on two days now and I'm hooked!
At first I was very unsure about giving up my Makefiles, being
the build system control freak that I am, but it really shines at
rapid development.
As for out of source builds, it is a non-issue really. I like
running the build outside the project tree but I can use
gitignore and targetPath. For larger projects where we need to
manage dependencies, generate code, run SWIG etc. I'd still use
both SCons or CMake.
Regarding parallel builds, make -j on CMake Makefiles and "dub
build" feel about the same, and that's all I care about.
I'm still not sure how dub would scale for large projects with
100s-1000s of source modules. DMD ran out of memory in the VM
(1Gb) at around 70 modules but CMake works due to separate
compilation of each module ... I think. However, I didn't
investigate due to lack of time so I wouldn't score this against
dub. I am sure it can do it if I take the time to figure it out
properly.
Cheers,
uri
