12.1 Build system overview

Build system is currently GNU make, with an extra "stepmake" layer on top. Look at files in ‘make/’ and ‘stepmake/’ and all ‘GNUmakefile’s.

There is wide-spread dissatisfaction with this system, and we are considering changing. This would be a huge undertaking (estimated 200+ hours). This change will probably involve not using GNU make any more – but a discussion about the precise build system will have to wait. Before we reach that point, we need to figure out (at least approximately) what the current build system does.

Fundamentally, a build system does two things:

  1. Constructs command-line commands, for example:
    lilypond-book \
      --tons --of --options \
    texi2pdf \
      --more --imperial --and --metric --tons --of --options \
  2. If there was a previous build, it decides which parts of the system need to be rebuilt.

When I try to do anything in the build system, it helps to remind myself of this. The "end result" is just a series of command-line commands. All the black magick is just an attempt to construct those commands.

LilyPond — Contributor’s Guide v2.19.10 (development-branch).