GOP-PROP 9 - behavior of make doc

If there are build problems, then it should be easier to find out why it’s failing. This will be achieved with log files, as well as possibly including scripts which automatically display portions of those log files for a failing build.

We will also add targets for building a specific manual (for quick+easy checking of doc work), as well as for building all documentation in a specific language (either English or a translated language).

When you run make doc,

If this proposal is accepted, none of these policies will be assumed to apply to any other aspect of the build system. Policies for any other aspect of the build system will be discussed in separate proposals.

Don’t cause more build problems

However, there is a danger in this approach, that vital error messages can also be lost, thus preventing the cause of the failure of a make being found. We therefore need to be exceptionally careful to move cautiously, include plenty of tests, and give time for people to experiment/find problems in each stage before proceeding to the next stage.

This will be done by starting from individual lilypond calls within lilypond-book, and slowly moving to “larger” targets of the build system – after the individual lilypond calls are are producing the appropriate amount of output and this is saved in the right place and we can automatically isolate parts of a failing build, we will work on lilypond-book in general, and only then will we look at the build system itself.

Implementation notes

There is an existing make variable QUIET_BUILD, which alter the amount of output being displayed (https://lilypond.org/doc/v2.15/Documentation/contributor/useful-make-variables ). We are not planning on keeping this make variable.

The standard way for GNU packages to give more output is with a V=x option. Presumably this is done by increasing x? If we support this option, we should still write log files; we would simply print more of the info in those log files to screen.

The command tee may be useful to write to a file and display to stdout (in the case of VERBOSE).

LilyPond — Contributor’s Guide v2.22.2 (stable-branch).