[bazel/ci] spliced mask_rom depends on meson built software

[drewmacrae]

This will also include a structured release artifact, with https://github.com/bazelbuild/rules_pkg/releases

[drewmacrae]

@cfrantz @a-will Am I reading the documentation for rules_pkg correctly that it doesn't support wildcards for artifacts? In the meantime I think it might be appropriate in CI use a copying shell script until we have a better notion of what we want to add to a release and make some filesets that point to it.

[a-will]

Hm... I'm not sure what you mean by "wildcards for artifacts." What are you looking to do with a wildcard?

[drewmacrae]

meson seems to wrap up all the products of sw/... that it knows how to build. It doesn't look to me like there's a way to do that without dropping an entry into each of 300 BUILD files.

[a-will]

meson seems to wrap up all the products of sw/... that it knows how to build. It doesn't look to me like there's a way to do that without dropping an entry into each of 300 BUILD files.

Mostly, meson allows us to distinguish between an OBJ_DIR and a BIN_DIR, and it happens to be convenient that the contents of the BIN_DIR is what you'd want in this case.

By contrast, bazel does not have that separation, so there isn't that convenient directory to simply copy over (without a lot of extra baggage, that is).

For what it's worth, we likely could get a representative list of targets with a bazel query, followed by some quick processing to extract the base directories and output those as prefixes to pkg_files rules. These don't need to be spread out across the BUILD files -- From any given BUILD file, we can grab any target from the workspace with the path (assuming the target doesn't restrict visibility... but we probably haven't paid close attention to that).