Thanks Paul and Andreas for raising this, I starting working on migrating scala to 2.12 and scala-asm is on the roadmap of the needed dependencies.
I have packages prepared to make it possible, but I need sponsors to move them forward. Here is the status: I can confirm Adam's diagnosis. The fix in progress is a bump of src:scala from 2.11.12 to 2.12.21+ds. 2.12 is the last series buildable without sbt (sbt was removed from Debian in 2023, #1035929, and 2.12+ requires it upstream). See this MR: https://salsa.debian.org/java-team/scala/-/merge_requests/2 The new scala embeds a transient 2.12.20 STARR seed as a build-time-only source input and self-hosts in a two-pass build; the seed is dropped after the first pass and scala self-bootstraps from the archive afterwards, so nothing prebuilt ships in the resulting binaries. It builds cleanly (sbuild unshare/unstable, lintian --pedantic clean) against scala-asm 9.9.0. It is still in draft pending review (the embedded seed needs a bootstrap exemption conversation with the FTP masters (not yet started), since prebuilt jars are present in the source for the first build even though they are not shipped). Review and a sponsor upload would unblock this bug's underlying migration issue, besides the version. This open the path to retire Scala 2.11 (scala-asm 9.x drops 5.x support), and the 14 reverse-dependencies of the old scala/scala-asm 5.x pair will need to follow; that is being tracked separately, and some of that work is already ongoing. Best, Juan PS: I would appreciate any advice on how to deal with the FTP masters conversation for the bootstrap exemption.

