Including GDC in nixpkgs

[Johannes Pfau]

Hi Stefan,

Am Fri, 20 Sep 2019 10:29:10 +0000 schrieb Stefan Frijters:

> As a fan of both D and the nixpkgs package manager I wanted to try and
> help include GDC in nixpkgs, but I have been running into some problems.
> 

Thank you a lot for looking at this and helping the D ecosystem!

> If anyone could help by taking a look at my pull request at
> https://github.com/NixOS/nixpkgs/pull/69144 that would be greatly
> appreciated.
> 
> Current issues include:
> 
> * When compiling without forcing --disable-shared, there are linker
> errors about needing to compile with -fPIC. It seems that some files are
> built using that flag, but not all, and I'm not sure how to go about
> forcing it for the rest.

This should not happen, -fPIC should be added automatically where 
required. Maybe it's caused by --enable-default-pie or any of the other 
flags which are not really needed?

> * When invoking nix-build without specifying --cores 1 there are
> problems when building libphobos; it looks like object files are moved
> before they are generated. This problem goes away when I build on a
> single core, but of course everything takes a very long time to try out.

Is this a problem during the make step or during make install? I don't 
think make install is multi-thread safe, but make should actually be fine.

> * I have disabled bootstrapping for now to speed up the debugging
> process, hopefully it can be enabled again later on.
> 
> I have taken the compiler flags to be used from
> https://aur.archlinux.org/cgit/aur.git/tree/PKGBUILD?h=gdc-git, which
> was linked in another thread on this forum, but maybe this is too
> specific for Arch?

Yes, these are actually arch and not gdc specific. You do not need any 
special flags for gdc, just add d to --enable-languages= and you should 
be fine. --with-target-system-zlib=yes is the only D specific flag in 
your github pull request, and it forces libphobos to link against the 
system zlib instead of including a copy. You'll have to decide whether 
this is the behavior you want.


-- 
Johannes