Bug#1139641: ITP: scala-2.12-bootstrap -- Scala 2.12 bootstrap reference compiler (STARR seed)

Package: wnpp
Severity: wishlist
Owner: Juan Manuel Méndez Rey <[email protected]>
X-Debbugs-Cc: [email protected], [email protected]

* Package name : scala-2.12-bootstrap
Version : 2.12.20
Upstream Author : Scala team, EPFL and Lightbend (Martin Odersky et al.)
URL : https://www.scala-lang.org
Source repo : https://github.com/scala/scala (branch 2.12.x)
License : Apache-2.0
Programming Lang: Scala, Java
Description : Scala 2.12 bootstrap reference compiler (STARR seed)

The Scala compiler is written in Scala, so building Scala 2.12 from source
requires a pre-existing Scala 2.12 compiler (the STARR -- Scala To Aid
Recompilation). This is the classic self-hosting-compiler chicken-and-egg: you
cannot start from javac (scalac is Scala) nor from the Scala 2.11 already in
Debian (2.12 uses features 2.11 cannot compile).
.
This package ships the prebuilt Scala 2.12.20 reference compiler (library,
reflect and compiler jars) used ONLY to bootstrap the src:scala-2.12 package
from source. Once scala-2.12 is built it rebuilds itself (self-host) and this
seed drops out of the closure -- the same stage0 model used by rustc, GHC and
OpenJDK.
.
NOTE FOR FTP MASTERS / debian-devel: this is a deliberate, documented binary
bootstrap seed and needs a bootstrap exemption, exactly as rustc/GHC/OpenJDK
have. I am filing this ITP to make the package concrete; the exemption itself
is a separate up-front discussion (see RFP #1125161). The seed is reproducible
and is dropped after stage 1 (self-host demonstrated). Related ITPs:
scala-2.12, sbt-util-interface (#1139638), sbt-compiler-interface (#1139639).
Packaging:
https://salsa.debian.org/mendezr/scala-2.12-bootstrap