Hi,
I'm trying to build and package my D application using the Nix "purely functional" package manager (
https://nixos.org/nix/).
A LITTLE INTRODUCTION
This package manager determines a unique hash from everything that goes into a build cycle (build scripts, sources, versions of dependencies, etc) and builds every derivation into a directory identified by that hash. Conversely, if a directory with that hash already exists, the package doesn't need to be built because it's up-to-date, by definition.
Because those hashes are very unlikely to occur by chance, the package manager crawls all files in the newly built directory for references to hashes of the input dependencies, and records those as run-time dependencies.
It's then possible to zip up a single package and all of its transitive run time dependencies, using the command nix-copy-closure (which for example includes the exact glibc the application was built against), and deploy it in a minimal busybox environment, for example.
MY ISSUE
This is all just a big preamble for my question: apparently, DMD leaves references to the compiler directory in a compiled binary. This causes the "dependency crawler" process to register DMD, and in turn all of _its_ dependencies, as run-time dependencies of my application, which is adding ~100MB to the size of my package bundle. Which, obviously, should not be necessary.
I can tell using 'strings' that they're all references to include files:
vagrant@vagrant-ubuntu-utopic-64:~$ strings webapp | grep dmd
/nix/store/3rj0sxwbp2lfddwya2smvkj4cl7y3lvs-dmd-2.066.1/include/d2/std/format.d-mixin-736
/nix/store/3rj0sxwbp2lfddwya2smvkj4cl7y3lvs-dmd-2.066.1/include/d2/std/format.d
/nix/store/3rj0sxwbp2lfddwya2smvkj4cl7y3lvs-dmd-2.066.1/include/d2/std/format.d
/nix/store/3rj0sxwbp2lfddwya2smvkj4cl7y3lvs-dmd-2.066.1/include/d2/std/uni.d
/nix/store/3rj0sxwbp2lfddwya2smvkj4cl7y3lvs-dmd-2.066.1/include/d2/std/variant.d
/nix/store/3rj0sxwbp2lfddwya2smvkj4cl7y3lvs-dmd-2.066.1/include/d2/core/demangle.d
/nix/store/3rj0sxwbp2lfddwya2smvkj4cl7y3lvs-dmd-2.066.1/include/d2/std/variant.d
But other than that, I'm at a loss as to what these strings are for, and more importantly, how I can get rid of them to cut my run-time dependency set.
Any ideas?
Thanks.