[gsoc] DUB - Ideas

[Jon Degenhardt]

On Thursday, 28 February 2019 at 15:50:49 UTC, Seb wrote:
> @community: what features do you miss the most from DUB?

Dub support for building code.dlang.org packages with LDC's LTO. 
The idea would be to support something analogous to the way LDC 
provides LTO support for druntime and phobos. See 
https://github.com/ldc-developers/ldc/releases/tag/v1.9.0 for a 
description.

Building with LTO against druntime/phobos is a substantial 
performance win for certain classes of programs. This would 
likely hold true for a number of code.dlang.org packages as well. 
My benchmarks involving druntime/phobos are here: 
https://github.com/eBay/tsv-utils/blob/master/docs/lto-pgo-study.md.

LDC supports druntime/phobos by shipping these prebuilt as LTO 
libraries (with IR code). For  packages it probably makes more 
sense to build them from source after being downloaded.

This is probably not a long project, but it might fit well as 
part of a suite of Dub changes. Dub may well have the necessary 
facilities already, I'm not sure, but this is not supported in a 
straightforward manner. There are likely some open questions, for 
example, should the package provider mark whether package 
supports LTO or not.