Add method to determine variations from a Target

The arch variants are hardcoded in every module type.  Refactor
them out into a Target.Variations() method in preparation for
splitting the arch mutator into two, which will require using
different variations.

Test: m checkbuild
Change-Id: I28ef7cd5168095ac888fe77f04e27f9ad81978c0

15 files changed, 92 insertions, 99 deletions

diff --git a/android/androidmk.go b/android/androidmk.go
index 90713477..b66fd183 100644
--- a/android/androidmk.go
+++ b/android/androidmk.go
@@ -199,19 +199,19 @@ func (a *AndroidMkEntries) fillInEntries(config Config, bpPath string, mod bluep
 	switch amod.Os().Class {
 	case Host:
 		// Make cannot identify LOCAL_MODULE_HOST_ARCH:= common.
-		if archStr != "common" {
+		if amod.Arch().ArchType != Common {
 			a.SetString("LOCAL_MODULE_HOST_ARCH", archStr)
 		}
 		host = true
 	case HostCross:
 		// Make cannot identify LOCAL_MODULE_HOST_CROSS_ARCH:= common.
-		if archStr != "common" {
+		if amod.Arch().ArchType != Common {
 			a.SetString("LOCAL_MODULE_HOST_CROSS_ARCH", archStr)
 		}
 		host = true
 	case Device:
 		// Make cannot identify LOCAL_MODULE_TARGET_ARCH:= common.
-		if archStr != "common" {
+		if amod.Arch().ArchType != Common {
 			if amod.Target().NativeBridge {
 				hostArchStr := amod.Target().NativeBridgeHostArchName
 				if hostArchStr != "" {
diff --git a/android/arch.go b/android/arch.go
index 348b0649..5887744e 100644
--- a/android/arch.go
+++ b/android/arch.go
@@ -22,9 +22,12 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/google/blueprint"
 	"github.com/google/blueprint/proptools"
 )
 
+const COMMON_VARIANT = "common"
+
 var (
 	archTypeList []ArchType
 
@@ -36,7 +39,7 @@ var (
 	X86_64 = newArch("x86_64", "lib64")
 
 	Common = ArchType{
-		Name: "common",
+		Name: COMMON_VARIANT,
 	}
 )
 
@@ -702,11 +705,23 @@ type Target struct {
 }
 
 func (target Target) String() string {
-	variant := ""
+	return target.ArchVariation()
+}
+
+func (target Target) ArchVariation() string {
+	var variation string
 	if target.NativeBridge {
-		variant = "native_bridge_"
+		variation = "native_bridge_"
+	}
+	variation += target.Arch.String()
+
+	return target.Os.String() + "_" + variation
+}
+
+func (target Target) Variations() []blueprint.Variation {
+	return []blueprint.Variation{
+		{Mutator: "arch", Variation: target.ArchVariation()},
 	}
-	return target.Os.String() + "_" + variant + target.Arch.String()
 }
 
 // archMutator splits a module into a variant for each Target requested by the module.  Target selection
diff --git a/android/config.go b/android/config.go
index 26c4e6eb..57737f17 100644
--- a/android/config.go
+++ b/android/config.go
@@ -89,9 +89,10 @@ type config struct {
 	ConfigFileName           string
 	ProductVariablesFileName string
 
-	Targets              map[OsType][]Target
-	BuildOsVariant       string
-	BuildOsCommonVariant string
+	Targets             map[OsType][]Target
+	BuildOSTarget       Target // the Target for tools run on the build machine
+	BuildOSCommonTarget Target // the Target for common (java) tools run on the build machine
+	AndroidCommonTarget Target // the Target for common modules for the Android device
 
 	// multilibConflicts for an ArchType is true if there is earlier configured device architecture with the same
 	// multilib value.
@@ -289,8 +290,9 @@ func TestArchConfig(buildDir string, env map[string]string) Config {
 		config.Targets[BuildOs] = config.Targets[BuildOs][:1]
 	}
 
-	config.BuildOsVariant = config.Targets[BuildOs][0].String()
-	config.BuildOsCommonVariant = getCommonTargets(config.Targets[BuildOs])[0].String()
+	config.BuildOSTarget = config.Targets[BuildOs][0]
+	config.BuildOSCommonTarget = getCommonTargets(config.Targets[BuildOs])[0]
+	config.AndroidCommonTarget = getCommonTargets(config.Targets[Android])[0]
 	config.TestProductVariables.DeviceArch = proptools.StringPtr("arm64")
 	config.TestProductVariables.DeviceArchVariant = proptools.StringPtr("armv8-a")
 	config.TestProductVariables.DeviceSecondaryArch = proptools.StringPtr("arm")
@@ -374,8 +376,11 @@ func NewConfig(srcDir, buildDir string) (Config, error) {
 	}
 
 	config.Targets = targets
-	config.BuildOsVariant = targets[BuildOs][0].String()
-	config.BuildOsCommonVariant = getCommonTargets(targets[BuildOs])[0].String()
+	config.BuildOSTarget = config.Targets[BuildOs][0]
+	config.BuildOSCommonTarget = getCommonTargets(config.Targets[BuildOs])[0]
+	if len(config.Targets[Android]) > 0 {
+		config.AndroidCommonTarget = getCommonTargets(config.Targets[Android])[0]
+	}
 
 	if err := config.fromEnv(); err != nil {
 		return Config{}, err
diff --git a/android/proto.go b/android/proto.go
index c8ade456..b712258e 100644
--- a/android/proto.go
+++ b/android/proto.go
@@ -52,9 +52,8 @@ func ProtoDeps(ctx BottomUpMutatorContext, p *ProtoProperties) {
 	}
 
 	if plugin := String(p.Proto.Plugin); plugin != "" {
-		ctx.AddFarVariationDependencies([]blueprint.Variation{
-			{Mutator: "arch", Variation: ctx.Config().BuildOsVariant},
-		}, ProtoPluginDepTag, "protoc-gen-"+plugin)
+		ctx.AddFarVariationDependencies(ctx.Config().BuildOSTarget.Variations(),
+			ProtoPluginDepTag, "protoc-gen-"+plugin)
 	}
 }
 
diff --git a/apex/apex.go b/apex/apex.go
index 5f714259..b02346a7 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -589,28 +589,25 @@ type apexBundle struct {
 
 func addDependenciesForNativeModules(ctx android.BottomUpMutatorContext,
 	native_shared_libs []string, binaries []string, tests []string,
-	arch string, imageVariation string) {
+	target android.Target, imageVariation string) {
 	// Use *FarVariation* to be able to depend on modules having
 	// conflicting variations with this module. This is required since
 	// arch variant of an APEX bundle is 'common' but it is 'arm' or 'arm64'
 	// for native shared libs.
-	ctx.AddFarVariationDependencies([]blueprint.Variation{
-		{Mutator: "arch", Variation: arch},
+	ctx.AddFarVariationDependencies(append(target.Variations(), []blueprint.Variation{
 		{Mutator: "image", Variation: imageVariation},
 		{Mutator: "link", Variation: "shared"},
 		{Mutator: "version", Variation: ""}, // "" is the non-stub variant
-	}, sharedLibTag, native_shared_libs...)
+	}...), sharedLibTag, native_shared_libs...)
 
-	ctx.AddFarVariationDependencies([]blueprint.Variation{
-		{Mutator: "arch", Variation: arch},
-		{Mutator: "image", Variation: imageVariation},
-	}, executableTag, binaries...)
+	ctx.AddFarVariationDependencies(append(target.Variations(),
+		blueprint.Variation{Mutator: "image", Variation: imageVariation}),
+		executableTag, binaries...)
 
-	ctx.AddFarVariationDependencies([]blueprint.Variation{
-		{Mutator: "arch", Variation: arch},
+	ctx.AddFarVariationDependencies(append(target.Variations(), []blueprint.Variation{
 		{Mutator: "image", Variation: imageVariation},
 		{Mutator: "test_per_src", Variation: ""}, // "" is the all-tests variant
-	}, testTag, tests...)
+	}...), testTag, tests...)
 }
 
 func (a *apexBundle) combineProperties(ctx android.BottomUpMutatorContext) {
@@ -642,49 +639,45 @@ func (a *apexBundle) DepsMutator(ctx android.BottomUpMutatorContext) {
 	for i, target := range targets {
 		// When multilib.* is omitted for native_shared_libs, it implies
 		// multilib.both.
-		ctx.AddFarVariationDependencies([]blueprint.Variation{
-			{Mutator: "arch", Variation: target.String()},
+		ctx.AddFarVariationDependencies(append(target.Variations(), []blueprint.Variation{
 			{Mutator: "image", Variation: a.getImageVariation(config)},
 			{Mutator: "link", Variation: "shared"},
-		}, sharedLibTag, a.properties.Native_shared_libs...)
+		}...), sharedLibTag, a.properties.Native_shared_libs...)
 
 		// When multilib.* is omitted for tests, it implies
 		// multilib.both.
-		ctx.AddFarVariationDependencies([]blueprint.Variation{
-			{Mutator: "arch", Variation: target.String()},
+		ctx.AddFarVariationDependencies(append(target.Variations(), []blueprint.Variation{
 			{Mutator: "image", Variation: a.getImageVariation(config)},
 			{Mutator: "test_per_src", Variation: ""}, // "" is the all-tests variant
-		}, testTag, a.properties.Tests...)
+		}...), testTag, a.properties.Tests...)
 
 		// Add native modules targetting both ABIs
 		addDependenciesForNativeModules(ctx,
 			a.properties.Multilib.Both.Native_shared_libs,
 			a.properties.Multilib.Both.Binaries,
 			a.properties.Multilib.Both.Tests,
-			target.String(),
+			target,
 			a.getImageVariation(config))
 
 		isPrimaryAbi := i == 0
 		if isPrimaryAbi {
 			// When multilib.* is omitted for binaries, it implies
 			// multilib.first.
-			ctx.AddFarVariationDependencies([]blueprint.Variation{
-				{Mutator: "arch", Variation: target.String()},
-				{Mutator: "image", Variation: a.getImageVariation(config)},
-			}, executableTag, a.properties.Binaries...)
+			ctx.AddFarVariationDependencies(append(target.Variations(),
+				blueprint.Variation{Mutator: "image", Variation: a.getImageVariation(config)}),
+				executableTag, a.properties.Binaries...)
 
 			// Add native modules targetting the first ABI
 			addDependenciesForNativeModules(ctx,
 				a.properties.Multilib.First.Native_shared_libs,
 				a.properties.Multilib.First.Binaries,
 				a.properties.Multilib.First.Tests,
-				target.String(),
+				target,
 				a.getImageVariation(config))
 
 			// When multilib.* is omitted for prebuilts, it implies multilib.first.
-			ctx.AddFarVariationDependencies([]blueprint.Variation{
-				{Mutator: "arch", Variation: target.String()},
-			}, prebuiltTag, a.properties.Prebuilts...)
+			ctx.AddFarVariationDependencies(target.Variations(),
+				prebuiltTag, a.properties.Prebuilts...)
 		}
 
 		switch target.Arch.ArchType.Multilib {
@@ -694,14 +687,14 @@ func (a *apexBundle) DepsMutator(ctx android.BottomUpMutatorContext) {
 				a.properties.Multilib.Lib32.Native_shared_libs,
 				a.properties.Multilib.Lib32.Binaries,
 				a.properties.Multilib.Lib32.Tests,
-				target.String(),
+				target,
 				a.getImageVariation(config))
 
 			addDependenciesForNativeModules(ctx,
 				a.properties.Multilib.Prefer32.Native_shared_libs,
 				a.properties.Multilib.Prefer32.Binaries,
 				a.properties.Multilib.Prefer32.Tests,
-				target.String(),
+				target,
 				a.getImageVariation(config))
 		case "lib64":
 			// Add native modules targetting 64-bit ABI
@@ -709,7 +702,7 @@ func (a *apexBundle) DepsMutator(ctx android.BottomUpMutatorContext) {
 				a.properties.Multilib.Lib64.Native_shared_libs,
 				a.properties.Multilib.Lib64.Binaries,
 				a.properties.Multilib.Lib64.Tests,
-				target.String(),
+				target,
 				a.getImageVariation(config))
 
 			if !has32BitTarget {
@@ -717,7 +710,7 @@ func (a *apexBundle) DepsMutator(ctx android.BottomUpMutatorContext) {
 					a.properties.Multilib.Prefer32.Native_shared_libs,
 					a.properties.Multilib.Prefer32.Binaries,
 					a.properties.Multilib.Prefer32.Tests,
-					target.String(),
+					target,
 					a.getImageVariation(config))
 			}
 
@@ -726,7 +719,7 @@ func (a *apexBundle) DepsMutator(ctx android.BottomUpMutatorContext) {
 					if sanitizer == "hwaddress" {
 						addDependenciesForNativeModules(ctx,
 							[]string{"libclang_rt.hwasan-aarch64-android"},
-							nil, nil, target.String(), a.getImageVariation(config))
+							nil, nil, target, a.getImageVariation(config))
 						break
 					}
 				}
@@ -735,13 +728,11 @@ func (a *apexBundle) DepsMutator(ctx android.BottomUpMutatorContext) {
 
 	}
 
-	ctx.AddFarVariationDependencies([]blueprint.Variation{
-		{Mutator: "arch", Variation: "android_common"},
-	}, javaLibTag, a.properties.Java_libs...)
+	ctx.AddFarVariationDependencies(ctx.Config().AndroidCommonTarget.Variations(),
+		javaLibTag, a.properties.Java_libs...)
 
-	ctx.AddFarVariationDependencies([]blueprint.Variation{
-		{Mutator: "arch", Variation: "android_common"},
-	}, androidAppTag, a.properties.Apps...)
+	ctx.AddFarVariationDependencies(ctx.Config().AndroidCommonTarget.Variations(),
+		androidAppTag, a.properties.Apps...)
 
 	if String(a.properties.Key) == "" {
 		ctx.ModuleErrorf("key is missing")
@@ -1645,17 +1636,17 @@ func (a *apexBundle) androidMkForFiles(w io.Writer, name, moduleDir string, apex
 			host := false
 			switch fi.module.Target().Os.Class {
 			case android.Host:
-				if archStr != "common" {
+				if fi.module.Target().Arch.ArchType != android.Common {
 					fmt.Fprintln(w, "LOCAL_MODULE_HOST_ARCH :=", archStr)
 				}
 				host = true
 			case android.HostCross:
-				if archStr != "common" {
+				if fi.module.Target().Arch.ArchType != android.Common {
 					fmt.Fprintln(w, "LOCAL_MODULE_HOST_CROSS_ARCH :=", archStr)
 				}
 				host = true
 			case android.Device:
-				if archStr != "common" {
+				if fi.module.Target().Arch.ArchType != android.Common {
 					fmt.Fprintln(w, "LOCAL_MODULE_TARGET_ARCH :=", archStr)
 				}
 			}
diff --git a/cc/cc.go b/cc/cc.go
index 0f2cb4c9..5c0aeb2a 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -1387,10 +1387,9 @@ func (c *Module) DepsMutator(actx android.BottomUpMutatorContext) {
 			depTag = headerExportDepTag
 		}
 		if buildStubs {
-			actx.AddFarVariationDependencies([]blueprint.Variation{
-				{Mutator: "arch", Variation: ctx.Target().String()},
-				{Mutator: "image", Variation: c.imageVariation()},
-			}, depTag, lib)
+			actx.AddFarVariationDependencies(append(ctx.Target().Variations(),
+				blueprint.Variation{Mutator: "image", Variation: c.imageVariation()}),
+				depTag, lib)
 		} else {
 			actx.AddVariationDependencies(nil, depTag, lib)
 		}
diff --git a/cc/sanitize.go b/cc/sanitize.go
index c0a7c63e..f568d5a6 100644
--- a/cc/sanitize.go
+++ b/cc/sanitize.go
@@ -878,18 +878,16 @@ func sanitizerRuntimeMutator(mctx android.BottomUpMutatorContext) {
 			// added to libFlags and LOCAL_SHARED_LIBRARIES by cc.Module
 			if c.staticBinary() {
 				// static executable gets static runtime libs
-				mctx.AddFarVariationDependencies([]blueprint.Variation{
+				mctx.AddFarVariationDependencies(append(mctx.Target().Variations(), []blueprint.Variation{
 					{Mutator: "link", Variation: "static"},
 					{Mutator: "image", Variation: c.imageVariation()},
-					{Mutator: "arch", Variation: mctx.Target().String()},
-				}, staticDepTag, runtimeLibrary)
+				}...), staticDepTag, runtimeLibrary)
 			} else if !c.static() && !c.header() {
 				// dynamic executable and shared libs get shared runtime libs
-				mctx.AddFarVariationDependencies([]blueprint.Variation{
+				mctx.AddFarVariationDependencies(append(mctx.Target().Variations(), []blueprint.Variation{
 					{Mutator: "link", Variation: "shared"},
 					{Mutator: "image", Variation: c.imageVariation()},
-					{Mutator: "arch", Variation: mctx.Target().String()},
-				}, earlySharedDepTag, runtimeLibrary)
+				}...), earlySharedDepTag, runtimeLibrary)
 			}
 			// static lib does not have dependency to the runtime library. The
 			// dependency will be added to the executables or shared libs using
diff --git a/genrule/genrule.go b/genrule/genrule.go
index c21df4c5..a7c5d65f 100644
--- a/genrule/genrule.go
+++ b/genrule/genrule.go
@@ -172,9 +172,7 @@ func (g *Module) DepsMutator(ctx android.BottomUpMutatorContext) {
 			if m := android.SrcIsModule(tool); m != "" {
 				tool = m
 			}
-			ctx.AddFarVariationDependencies([]blueprint.Variation{
-				{Mutator: "arch", Variation: ctx.Config().BuildOsVariant},
-			}, tag, tool)
+			ctx.AddFarVariationDependencies(ctx.Config().BuildOSTarget.Variations(), tag, tool)
 		}
 	}
 }
diff --git a/java/app.go b/java/app.go
index e0336617..6b640f1c 100644
--- a/java/app.go
+++ b/java/app.go
@@ -167,10 +167,8 @@ func (a *AndroidApp) DepsMutator(ctx android.BottomUpMutatorContext) {
 
 	embedJni := a.shouldEmbedJnis(ctx)
 	for _, jniTarget := range ctx.MultiTargets() {
-		variation := []blueprint.Variation{
-			{Mutator: "arch", Variation: jniTarget.String()},
-			{Mutator: "link", Variation: "shared"},
-		}
+		variation := append(jniTarget.Variations(),
+			blueprint.Variation{Mutator: "link", Variation: "shared"})
 		tag := &jniDependencyTag{
 			target: jniTarget,
 		}
diff --git a/java/device_host_converter.go b/java/device_host_converter.go
index 030b0106..14db5215 100644
--- a/java/device_host_converter.go
+++ b/java/device_host_converter.go
@@ -18,8 +18,6 @@ import (
 	"fmt"
 	"io"
 
-	"github.com/google/blueprint"
-
 	"android/soong/android"
 )
 
@@ -83,13 +81,13 @@ func HostForDeviceFactory() android.Module {
 var deviceHostConverterDepTag = dependencyTag{name: "device_host_converter"}
 
 func (d *DeviceForHost) DepsMutator(ctx android.BottomUpMutatorContext) {
-	variation := []blueprint.Variation{{Mutator: "arch", Variation: "android_common"}}
-	ctx.AddFarVariationDependencies(variation, deviceHostConverterDepTag, d.properties.Libs...)
+	ctx.AddFarVariationDependencies(ctx.Config().AndroidCommonTarget.Variations(),
+		deviceHostConverterDepTag, d.properties.Libs...)
 }
 
 func (d *HostForDevice) DepsMutator(ctx android.BottomUpMutatorContext) {
-	variation := []blueprint.Variation{{Mutator: "arch", Variation: ctx.Config().BuildOsCommonVariant}}
-	ctx.AddFarVariationDependencies(variation, deviceHostConverterDepTag, d.properties.Libs...)
+	ctx.AddFarVariationDependencies(ctx.Config().BuildOSCommonTarget.Variations(),
+		deviceHostConverterDepTag, d.properties.Libs...)
 }
 
 func (d *DeviceHostConverter) GenerateAndroidBuildActions(ctx android.ModuleContext) {
diff --git a/java/device_host_converter_test.go b/java/device_host_converter_test.go
index 44aae9b3..3c9a0f3f 100644
--- a/java/device_host_converter_test.go
+++ b/java/device_host_converter_test.go
@@ -60,7 +60,7 @@ func TestDeviceForHost(t *testing.T) {
 	deviceImportModule := ctx.ModuleForTests("device_import_module", "android_common")
 	deviceImportCombined := deviceImportModule.Output("combined/device_import_module.jar")
 
-	hostModule := ctx.ModuleForTests("host_module", config.BuildOsCommonVariant)
+	hostModule := ctx.ModuleForTests("host_module", config.BuildOSCommonTarget.String())
 	hostJavac := hostModule.Output("javac/host_module.jar")
 	hostRes := hostModule.Output("res/host_module.jar")
 	combined := hostModule.Output("combined/host_module.jar")
@@ -133,11 +133,11 @@ func TestHostForDevice(t *testing.T) {
 
 	ctx, config := testJava(t, bp)
 
-	hostModule := ctx.ModuleForTests("host_module", config.BuildOsCommonVariant)
+	hostModule := ctx.ModuleForTests("host_module", config.BuildOSCommonTarget.String())
 	hostJavac := hostModule.Output("javac/host_module.jar")
 	hostRes := hostModule.Output("res/host_module.jar")
 
-	hostImportModule := ctx.ModuleForTests("host_import_module", config.BuildOsCommonVariant)
+	hostImportModule := ctx.ModuleForTests("host_import_module", config.BuildOSCommonTarget.String())
 	hostImportCombined := hostImportModule.Output("combined/host_import_module.jar")
 
 	deviceModule := ctx.ModuleForTests("device_module", "android_common")
diff --git a/java/java.go b/java/java.go
index 4264ba90..47fb1a7b 100644
--- a/java/java.go
+++ b/java/java.go
@@ -546,9 +546,7 @@ func (j *Module) deps(ctx android.BottomUpMutatorContext) {
 	ctx.AddVariationDependencies(nil, libTag, j.properties.Libs...)
 	ctx.AddVariationDependencies(nil, staticLibTag, j.properties.Static_libs...)
 
-	ctx.AddFarVariationDependencies([]blueprint.Variation{
-		{Mutator: "arch", Variation: ctx.Config().BuildOsCommonVariant},
-	}, pluginTag, j.properties.Plugins...)
+	ctx.AddFarVariationDependencies(ctx.Config().BuildOSCommonTarget.Variations(), pluginTag, j.properties.Plugins...)
 
 	android.ProtoDeps(ctx, &j.protoProperties)
 	if j.hasSrcExt(".proto") {
diff --git a/python/python.go b/python/python.go
index ad089090..1b606cbb 100644
--- a/python/python.go
+++ b/python/python.go
@@ -306,22 +306,17 @@ func (p *Module) DepsMutator(ctx android.BottomUpMutatorContext) {
 			if p.bootstrapper.autorun() {
 				launcherModule = "py2-launcher-autorun"
 			}
-			ctx.AddFarVariationDependencies([]blueprint.Variation{
-				{Mutator: "arch", Variation: ctx.Target().String()},
-			}, launcherTag, launcherModule)
+			ctx.AddFarVariationDependencies(ctx.Target().Variations(), launcherTag, launcherModule)
 
 			// Add py2-launcher shared lib dependencies. Ideally, these should be
 			// derived from the `shared_libs` property of "py2-launcher". However, we
 			// cannot read the property at this stage and it will be too late to add
 			// dependencies later.
-			ctx.AddFarVariationDependencies([]blueprint.Variation{
-				{Mutator: "arch", Variation: ctx.Target().String()},
-			}, launcherSharedLibTag, "libsqlite")
+			ctx.AddFarVariationDependencies(ctx.Target().Variations(), launcherSharedLibTag, "libsqlite")
 
 			if ctx.Target().Os.Bionic() {
-				ctx.AddFarVariationDependencies([]blueprint.Variation{
-					{Mutator: "arch", Variation: ctx.Target().String()},
-				}, launcherSharedLibTag, "libc", "libdl", "libm")
+				ctx.AddFarVariationDependencies(ctx.Target().Variations(), launcherSharedLibTag,
+					"libc", "libdl", "libm")
 			}
 		}
 
diff --git a/rust/rust.go b/rust/rust.go
index 61b51e54..4f5e7fb9 100644
--- a/rust/rust.go
+++ b/rust/rust.go
@@ -496,7 +496,7 @@ func (mod *Module) DepsMutator(actx android.BottomUpMutatorContext) {
 	}
 
 	// proc_macros are compiler plugins, and so we need the host arch variant as a dependendcy.
-	actx.AddFarVariationDependencies([]blueprint.Variation{{Mutator: "arch", Variation: ctx.Config().BuildOsVariant}}, procMacroDepTag, deps.ProcMacros...)
+	actx.AddFarVariationDependencies(ctx.Config().BuildOSTarget.Variations(), procMacroDepTag, deps.ProcMacros...)
 }
 
 func (mod *Module) Name() string {
diff --git a/sdk/sdk.go b/sdk/sdk.go
index fcb3fb7f..3736103f 100644
--- a/sdk/sdk.go
+++ b/sdk/sdk.go
@@ -101,11 +101,10 @@ func memberMutator(mctx android.BottomUpMutatorContext) {
 
 		targets := mctx.MultiTargets()
 		for _, target := range targets {
-			mctx.AddFarVariationDependencies([]blueprint.Variation{
-				{Mutator: "arch", Variation: target.String()},
+			mctx.AddFarVariationDependencies(append(target.Variations(), []blueprint.Variation{
 				{Mutator: "image", Variation: "core"},
 				{Mutator: "link", Variation: "shared"},
-			}, sdkMemberDepTag, m.properties.Native_shared_libs...)
+			}...), sdkMemberDepTag, m.properties.Native_shared_libs...)
 		}
 	}
 }