Hello Guix, ‘rust-ring-0.16-sources’ & co. are origins that use ‘computed-origin-method’ (the thing that’s internal and undocumented) to generate object files from assembly source, things like that.
An origin is supposed to represent source code, and clearly, the end result here is not source by any stretch. I believe it’s done this way simply because ‘cargo-build-system’ then embarks that “source” to build leaf package(s) that use ‘rust-ring’, directly or indirectly; this is where Rust compilation actually takes place and, IIUC, the reason why a build phase in ‘rust-ring’ would be of no use. Anyway, the ‘computed-origin-method’ hack prevents input rewriting from working as expected because the inputs of that big gexp aren’t visible by just traversing the package graph. That’s a problem. Ideas on how to fix that? An idea that comes to mind is to turn ‘rust-ring-0.16-sources’ into a package using ‘trivial-build-system’, though I’m not sure it would work well with ‘cargo-build-system’. Ludo’.
