1 files changed, 76 insertions, 24 deletions

diff --git a/internal/rosa/rosa.go b/internal/rosa/rosa.go
index c1f71cfa..e83d7097 100644
--- a/internal/rosa/rosa.go
+++ b/internal/rosa/rosa.go
@@ -268,11 +268,10 @@ function apply {
 
 	return t.New(name+"-src", Unversioned, nil, &PackageAttr{
 		Paths: paths,
+		Tools: P{_patch},
 	}, &GenericHelper{
 		Build: buf.String(),
-	},
-		_patch,
-	)
+	})
 }
 
 // helperInPlace is a special directory value for omitting the cd statement.
@@ -338,6 +337,8 @@ type PackageAttr struct {
 	// Whether to create [pkg.KindExecNet] instead of [pkg.KindExec].
 	HostNet bool
 
+	// Inputs added only during cross-compilation.
+	Cross P
 	// Native utilities used by the build process.
 	Tools P
 	// Unregistered extras.
@@ -419,9 +420,16 @@ func (t Toolchain) New(
 	root := make([]pkg.Artifact, 0, 1<<3+
 		len(attr.Extra)+
 		len(attr.Tools)+
+		len(attr.Cross)+
 		len(inputs))
 	root = append(root, attr.Extra...)
 
+	cross := t.cross()
+	var rootCross []pkg.Artifact
+	if cross {
+		rootCross = make([]pkg.Artifact, 0, len(inputs)+len(attr.Cross))
+	}
+
 	const lcMessages = "LC_MESSAGES=C.UTF-8"
 	srn := rn
 	env := slices.Clone(attr.Env)
@@ -490,24 +498,51 @@ func (t Toolchain) New(
 
 	wantsChmod, wantsWrite := helper.wantsChmod(), helper.wantsWrite()
 	{
+		native := t.native()
 		pv := paGet()
+		spv := pv
+		if cross {
+			spv = paGet()
+		}
 		for _, p := range helper.tools() {
-			root = t.appendHandle(root, pv, p)
+			root = native.appendHandle(root, pv, p)
 		}
-		for _, p := range helper.inputs() {
-			root = t.appendHandle(root, pv, p)
+
+		if !cross {
+			for _, p := range helper.inputs() {
+				root = t.appendHandle(root, spv, p)
+			}
+		} else {
+			for _, p := range helper.inputs() {
+				rootCross = t.appendHandle(rootCross, spv, p)
+			}
 		}
+
 		for _, p := range attr.Tools {
-			root = t.appendHandle(root, pv, p)
+			root = native.appendHandle(root, pv, p)
 		}
-		for _, p := range inputs {
-			root = t.appendHandle(root, pv, p)
+
+		if !cross {
+			for _, p := range inputs {
+				root = t.appendHandle(root, spv, p)
+			}
+		} else {
+			for _, p := range inputs {
+				rootCross = t.appendHandle(rootCross, spv, p)
+			}
+			for _, p := range attr.Cross {
+				rootCross = t.appendHandle(rootCross, spv, p)
+			}
 		}
-		boot := t.S.New(t.stage - 1)
+
+		boot := native.S.New(t.stage - 1)
 		for _, p := range extraBoot {
 			root = boot.appendHandle(root, pv, p)
 		}
 		paPut(pv)
+		if cross {
+			paPut(spv)
+		}
 	}
 
 	if t.stage == stageGentoo {
@@ -569,37 +604,51 @@ ln -s ../bin /usr/`
 		scriptEarly += " /bin/)\n"
 	}
 
+	arch := t.Arch()
+	sys := []pkg.ExecPath{pkg.Path(
+		fhs.AbsRoot, true,
+		root...,
+	), pkg.Path(
+		absCureScript, false,
+		pkg.NewFile(scriptName, []byte(
+			"#!/system/bin/sh\n"+
+				"set -eu -o pipefail\n"+
+				scriptEarly+helper.script(t, name),
+		)),
+	)}
+	if cross {
+		var _arch string
+		_arch, arch = arch, t.S.native.Arch()
+		if len(rootCross) > 0 {
+			sys = append(sys, pkg.Path(
+				AbsSystem.Append(_arch), true,
+				rootCross...,
+			))
+		}
+		srn += "-cross-" + _arch
+	}
+
 	return pkg.NewExec(
-		srn, t.arch, attr.KnownChecksum, pkg.ExecTimeoutMax,
+		srn, arch, attr.KnownChecksum, pkg.ExecTimeoutMax,
 		attr.HostNet,
 		attr.Exclusive,
 		fhs.AbsRoot, env,
 		absCureScript,
 		nil,
 
-		slices.Concat([]pkg.ExecPath{pkg.Path(
-			fhs.AbsRoot, true,
-			root...,
-		), pkg.Path(
-			absCureScript, false,
-			pkg.NewFile(scriptName, []byte(
-				"#!/system/bin/sh\n"+
-					"set -eu -o pipefail\n"+
-					scriptEarly+helper.script(t, name),
-			)),
-		)}, paths)...,
+		slices.Concat(sys, paths)...,
 	)
 }
 
 // GenericHelper directly passes build script segments for invocations of
 // one-off build scripts too specific to fit into any other [Helper]
-// implementation, but can still benefit from [Toolchain.NewPackage].
+// implementation, but can still benefit from [Toolchain.New].
 type GenericHelper struct {
 	// Remain in current directory.
 	InPlace bool
 
 	// Concatenated for [Toolchain].
-	Build, Check, Install string
+	Cross, Build, Check, Install string
 }
 
 var _ Helper = new(GenericHelper)
@@ -634,6 +683,9 @@ func (attr *GenericHelper) script(t Toolchain, _ string) string {
 	}
 
 	script := attr.Build
+	if t.cross() {
+		script = attr.Cross + script
+	}
 	if t.opts&OptSkipCheck == 0 {
 		script += attr.Check
 	}