internal/rosa: self-host stage0 tarball

This replaces gentoo stage3 tarballs.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/mbf/main.go

@@ -109,6 +109,10 @@ func main() {
 		)
 	}
 
+	{
+		var (
+			flagStage0 bool
+		)
 		c.NewCommand(
 			"stage3",
 			"Check for toolchain 3-stage non-determinism",
@@ -146,9 +150,25 @@ func main() {
 						"("+pkg.Encode(checksum[0].Value())+")",
 					)
 				}
+
+				if flagStage0 {
+					if pathname, _, err = cache.Cure(
+						rosa.Std.Load(rosa.Stage0),
+					); err != nil {
+						return err
+					}
+					log.Println(pathname)
+				}
+
 				return
 			},
+		).
+			Flag(
+				&flagStage0,
+				"stage0", command.BoolFlag(false),
+				"Create bootstrap stage0 tarball",
 			)
+	}
 
 	{
 		var (

internal/rosa/all.go

@@ -83,6 +83,10 @@ const (
 	// stages only. This preset and its direct output must never be exposed.
 	gcc
 
+	// Stage0 is a tarball containing all compile-time dependencies of artifacts
+	// part of the [Std] toolchain.
+	Stage0
+
 	// _presetEnd is the total number of presets and does not denote a preset.
 	_presetEnd
 )

internal/rosa/stage0.go

@@ -0,0 +1,39 @@
+package rosa
+
+import "hakurei.app/internal/pkg"
+
+func (t Toolchain) newStage0() pkg.Artifact {
+	musl, compilerRT, runtimes, clang := t.NewLLVM()
+	return t.New("rosa-stage0", 0, []pkg.Artifact{
+		musl,
+		compilerRT,
+		runtimes,
+		clang,
+
+		t.Load(Bzip2),
+
+		t.Load(Patch),
+		t.Load(Make),
+		t.Load(CMake),
+		t.Load(Ninja),
+
+		t.Load(Libffi),
+		t.Load(Python),
+		t.Load(Perl),
+		t.Load(Diffutils),
+		t.Load(Bash),
+		t.Load(Gawk),
+		t.Load(Coreutils),
+		t.Load(Findutils),
+
+		t.Load(KernelHeaders),
+	}, nil, nil, `
+umask 377
+tar \
+	-vjc \
+	-C / \
+	-f /work/stage0-`+triplet()+`.tar.bz2 \
+	system bin usr/bin/env
+`)
+}
+func init() { artifactsF[Stage0] = Toolchain.newStage0 }

internal/rosa/toybox.go

@@ -16,7 +16,9 @@ func (t Toolchain) newToybox(suffix, script string) pkg.Artifact {
 	), nil, stage0Concat(t, []string{},
 		"ROSA_CHECK=make USER=cure tests",
 	), `
-ln -s ../system/bin/bash /bin/ || true
+chmod +w /bin/
+ln -sf ../system/bin/bash /bin/
+
 cd /usr/src/toybox
 chmod +w kconfig tests
 rm \