Merge "Add bazel_module properties to cc_defaults"
diff --git a/android/Android.bp b/android/Android.bp
index 773aa6a..a32e8f2 100644
--- a/android/Android.bp
+++ b/android/Android.bp
@@ -67,6 +67,7 @@
         "rule_builder.go",
         "sandbox.go",
         "sdk.go",
+        "sdk_version.go",
         "singleton.go",
         "singleton_module.go",
         "soong_config_modules.go",
diff --git a/android/apex.go b/android/apex.go
index 01ac9b3..7f9f0f5 100644
--- a/android/apex.go
+++ b/android/apex.go
@@ -809,8 +809,10 @@
 	"androidx.arch.core_core-common-nodeps":                    29,
 	"androidx.collection_collection-nodeps":                    29,
 	"androidx.collection_collection-ktx-nodeps":                30,
+	"androidx.concurrent_concurrent-futures-nodeps":            30,
 	"androidx.lifecycle_lifecycle-common-java8-nodeps":         30,
 	"androidx.lifecycle_lifecycle-common-nodeps":               29,
+	"androidx.room_room-common-nodeps":                         30,
 	"androidx-constraintlayout_constraintlayout-solver-nodeps": 29,
 	"apache-commons-compress":                                  29,
 	"bouncycastle_ike_digests":                                 30,
@@ -820,6 +822,7 @@
 	"flatbuffer_headers":                                       30,
 	"framework-permission":                                     30,
 	"gemmlowp_headers":                                         30,
+	"guava-listenablefuture-prebuilt-jar":                      30,
 	"ike-internals":                                            30,
 	"kotlinx-coroutines-android":                               28,
 	"kotlinx-coroutines-android-nodeps":                        30,
diff --git a/android/api_levels.go b/android/api_levels.go
index 2f6a9d2..9bc7e83 100644
--- a/android/api_levels.go
+++ b/android/api_levels.go
@@ -31,9 +31,9 @@
 // ApiLevelFromUser or ApiLevelOrPanic.
 //
 // The different *types* of API levels are handled separately. Currently only
-// Java has these, and they're managed with the sdkKind enum of the sdkSpec. A
-// future cleanup should be to migrate sdkSpec to using ApiLevel instead of its
-// sdkVersion int, and to move sdkSpec into this package.
+// Java has these, and they're managed with the SdkKind enum of the SdkSpec. A
+// future cleanup should be to migrate SdkSpec to using ApiLevel instead of its
+// SdkVersion int, and to move SdkSpec into this package.
 type ApiLevel struct {
 	// The string representation of the API level.
 	value string
diff --git a/android/arch.go b/android/arch.go
index 20b4ab0..3eff5d5 100644
--- a/android/arch.go
+++ b/android/arch.go
@@ -1709,3 +1709,90 @@
 	}
 	return archToProp
 }
+
+// GetTargetProperties returns a map of OS target (e.g. android, windows) to the
+// values of the properties of the 'dst' struct that are specific to that OS
+// target.
+//
+// For example, passing a struct { Foo bool, Bar string } will return an
+// interface{} that can be type asserted back into the same struct, containing
+// the os-specific property value specified by the module if defined.
+//
+// While this looks similar to GetArchProperties, the internal representation of
+// the properties have a slightly different layout to warrant a standalone
+// lookup function.
+func (m *ModuleBase) GetTargetProperties(dst interface{}) map[OsType]interface{} {
+	// Return value of the arch types to the prop values for that arch.
+	osToProp := map[OsType]interface{}{}
+
+	// Nothing to do for non-OS/arch-specific modules.
+	if !m.ArchSpecific() {
+		return osToProp
+	}
+
+	// archProperties has the type of [][]interface{}. Looks complicated, so
+	// let's explain this step by step.
+	//
+	// Loop over the outer index, which determines the property struct that
+	// contains a matching set of properties in dst that we're interested in.
+	// For example, BaseCompilerProperties or BaseLinkerProperties.
+	for i := range m.archProperties {
+		if m.archProperties[i] == nil {
+			continue
+		}
+
+		// Iterate over the supported OS types
+		for _, os := range OsTypeList {
+			// e.g android, linux_bionic
+			field := os.Field
+
+			// If it's not nil, loop over the inner index, which determines the arch variant
+			// of the prop type. In an Android.bp file, this is like looping over:
+			//
+			// target: { android: { key: value, ... }, linux_bionic: { key: value, ... } }
+			for _, archProperties := range m.archProperties[i] {
+				archPropValues := reflect.ValueOf(archProperties).Elem()
+
+				// This is the archPropRoot struct. Traverse into the Targetnested struct.
+				src := archPropValues.FieldByName("Target").Elem()
+
+				// Step into non-nil pointers to structs in the src value.
+				if src.Kind() == reflect.Ptr {
+					if src.IsNil() {
+						continue
+					}
+					src = src.Elem()
+				}
+
+				// Find the requested field (e.g. android, linux_bionic) in the src struct.
+				src = src.FieldByName(field)
+
+				// Validation steps. We want valid non-nil pointers to structs.
+				if !src.IsValid() || src.IsNil() {
+					continue
+				}
+
+				if src.Kind() != reflect.Ptr || src.Elem().Kind() != reflect.Struct {
+					continue
+				}
+
+				// Clone the destination prop, since we want a unique prop struct per arch.
+				dstClone := reflect.New(reflect.ValueOf(dst).Elem().Type()).Interface()
+
+				// Copy the located property struct into the cloned destination property struct.
+				err := proptools.ExtendMatchingProperties([]interface{}{dstClone}, src.Interface(), nil, proptools.OrderReplace)
+				if err != nil {
+					// This is fine, it just means the src struct doesn't match.
+					continue
+				}
+
+				// Found the prop for the os, you have.
+				osToProp[os] = dstClone
+
+				// Go to the next prop.
+				break
+			}
+		}
+	}
+	return osToProp
+}
diff --git a/android/bazel.go b/android/bazel.go
index 51ff3cb..2587328 100644
--- a/android/bazel.go
+++ b/android/bazel.go
@@ -108,6 +108,11 @@
 type BazelConversionConfigEntry int
 
 const (
+	// A sentinel value to be used as a key in Bp2BuildConfig for modules with
+	// no package path. This is also the module dir for top level Android.bp
+	// modules.
+	BP2BUILD_TOPLEVEL = "."
+
 	// iota + 1 ensures that the int value is not 0 when used in the Bp2buildAllowlist map,
 	// which can also mean that the key doesn't exist in a lookup.
 
@@ -224,10 +229,15 @@
 func bp2buildDefaultTrueRecursively(packagePath string, config Bp2BuildConfig) bool {
 	ret := false
 
+	// Return exact matches in the config.
+	if config[packagePath] == Bp2BuildDefaultTrueRecursively {
+		return true
+	}
 	if config[packagePath] == Bp2BuildDefaultFalse {
 		return false
 	}
 
+	// If not, check for the config recursively.
 	packagePrefix := ""
 	// e.g. for x/y/z, iterate over x, x/y, then x/y/z, taking the final value from the allowlist.
 	for _, part := range strings.Split(packagePath, "/") {
diff --git a/android/bazel_handler.go b/android/bazel_handler.go
index abc793f..04b70d6 100644
--- a/android/bazel_handler.go
+++ b/android/bazel_handler.go
@@ -270,13 +270,23 @@
 	cmdFlags = append(cmdFlags, labels...)
 	cmdFlags = append(cmdFlags, "--package_path=%workspace%/"+context.intermediatesDir())
 	cmdFlags = append(cmdFlags, "--profile="+shared.BazelMetricsFilename(context, runName))
-	// Set default platforms to canonicalized values for mixed builds requests. If these are set
-	// in the bazelrc, they will have values that are non-canonicalized, and thus be invalid.
-	// The actual platform values here may be overridden by configuration transitions from the buildroot.
+
+	// Set default platforms to canonicalized values for mixed builds requests.
+	// If these are set in the bazelrc, they will have values that are
+	// non-canonicalized to @sourceroot labels, and thus be invalid when
+	// referenced from the buildroot.
+	//
+	// The actual platform values here may be overridden by configuration
+	// transitions from the buildroot.
 	cmdFlags = append(cmdFlags,
-		fmt.Sprintf("--platforms=%s", canonicalizeLabel("//build/bazel/platforms:generic_x86_64")))
+		fmt.Sprintf("--platforms=%s", canonicalizeLabel("//build/bazel/platforms:android_x86_64")))
 	cmdFlags = append(cmdFlags,
 		fmt.Sprintf("--extra_toolchains=%s", canonicalizeLabel("//prebuilts/clang/host/linux-x86:all")))
+	// This should be parameterized on the host OS, but let's restrict to linux
+	// to keep things simple for now.
+	cmdFlags = append(cmdFlags,
+		fmt.Sprintf("--host_platform=%s", canonicalizeLabel("//build/bazel/platforms:linux_x86_64")))
+
 	// Explicitly disable downloading rules (such as canonical C++ and Java rules) from the network.
 	cmdFlags = append(cmdFlags, "--experimental_repository_disable_download")
 	cmdFlags = append(cmdFlags, extraFlags...)
@@ -328,7 +338,7 @@
 
 def _config_node_transition_impl(settings, attr):
     return {
-        "//command_line_option:platforms": "@sourceroot//build/bazel/platforms:generic_%s" % attr.arch,
+        "//command_line_option:platforms": "@sourceroot//build/bazel/platforms:android_%s" % attr.arch,
     }
 
 _config_node_transition = transition(
@@ -504,10 +514,10 @@
   platform_name = build_options(target)["//command_line_option:platforms"][0].name
   if platform_name == "host":
     return "HOST"
-  elif not platform_name.startswith("generic_"):
-    fail("expected platform name of the form 'generic_<arch>', but was " + str(platforms))
+  elif not platform_name.startswith("android_"):
+    fail("expected platform name of the form 'android_<arch>', but was " + str(platforms))
     return "UNKNOWN"
-  return platform_name[len("generic_"):]
+  return platform_name[len("android_"):]
 
 def format(target):
   id_string = str(target.label) + "|" + get_arch(target)
@@ -692,6 +702,10 @@
 			cmd.Implicit(PathForBazelOut(ctx, inputPath))
 		}
 
+		if depfile := buildStatement.Depfile; depfile != nil {
+			cmd.ImplicitDepFile(PathForBazelOut(ctx, *depfile))
+		}
+
 		// This is required to silence warnings pertaining to unexpected timestamps. Particularly,
 		// some Bazel builtins (such as files in the bazel_tools directory) have far-future
 		// timestamps. Without restat, Ninja would emit warnings that the input files of a
diff --git a/android/sdk_version.go b/android/sdk_version.go
new file mode 100644
index 0000000..ce22b5f
--- /dev/null
+++ b/android/sdk_version.go
@@ -0,0 +1,311 @@
+// Copyright 2021 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package android
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+type SdkContext interface {
+	// SdkVersion returns SdkSpec that corresponds to the sdk_version property of the current module
+	SdkVersion() SdkSpec
+	// SystemModules returns the system_modules property of the current module, or an empty string if it is not set.
+	SystemModules() string
+	// MinSdkVersion returns SdkSpec that corresponds to the min_sdk_version property of the current module,
+	// or from sdk_version if it is not set.
+	MinSdkVersion() SdkSpec
+	// TargetSdkVersion returns the SdkSpec that corresponds to the target_sdk_version property of the current module,
+	// or from sdk_version if it is not set.
+	TargetSdkVersion() SdkSpec
+}
+
+// SdkKind represents a particular category of an SDK spec like public, system, test, etc.
+type SdkKind int
+
+const (
+	SdkInvalid SdkKind = iota
+	SdkNone
+	SdkCore
+	SdkCorePlatform
+	SdkPublic
+	SdkSystem
+	SdkTest
+	SdkModule
+	SdkSystemServer
+	SdkPrivate
+)
+
+// String returns the string representation of this SdkKind
+func (k SdkKind) String() string {
+	switch k {
+	case SdkPrivate:
+		return "private"
+	case SdkNone:
+		return "none"
+	case SdkPublic:
+		return "public"
+	case SdkSystem:
+		return "system"
+	case SdkTest:
+		return "test"
+	case SdkCore:
+		return "core"
+	case SdkCorePlatform:
+		return "core_platform"
+	case SdkModule:
+		return "module-lib"
+	case SdkSystemServer:
+		return "system-server"
+	default:
+		return "invalid"
+	}
+}
+
+// SdkVersion represents a specific version number of an SDK spec of a particular kind
+type SdkVersion int
+
+const (
+	// special version number for a not-yet-frozen SDK
+	SdkVersionCurrent SdkVersion = SdkVersion(FutureApiLevelInt)
+	// special version number to be used for SDK specs where version number doesn't
+	// make sense, e.g. "none", "", etc.
+	SdkVersionNone SdkVersion = SdkVersion(0)
+)
+
+// IsCurrent checks if the SdkVersion refers to the not-yet-published version of an SdkKind
+func (v SdkVersion) IsCurrent() bool {
+	return v == SdkVersionCurrent
+}
+
+// IsNumbered checks if the SdkVersion refers to the published (a.k.a numbered) version of an SdkKind
+func (v SdkVersion) IsNumbered() bool {
+	return !v.IsCurrent() && v != SdkVersionNone
+}
+
+// String returns the string representation of this SdkVersion.
+func (v SdkVersion) String() string {
+	if v.IsCurrent() {
+		return "current"
+	} else if v.IsNumbered() {
+		return strconv.Itoa(int(v))
+	}
+	return "(no version)"
+}
+
+func (v SdkVersion) ApiLevel(ctx EarlyModuleContext) ApiLevel {
+	return ApiLevelOrPanic(ctx, v.String())
+}
+
+// AsNumberString directly converts the numeric value of this sdk version as a string.
+// When isNumbered() is true, this method is the same as String(). However, for SdkVersionCurrent
+// and SdkVersionNone, this returns 10000 and 0 while String() returns "current" and "(no version"),
+// respectively.
+func (v SdkVersion) AsNumberString() string {
+	return strconv.Itoa(int(v))
+}
+
+// SdkSpec represents the kind and the version of an SDK for a module to build against
+type SdkSpec struct {
+	Kind    SdkKind
+	Version SdkVersion
+	Raw     string
+}
+
+func (s SdkSpec) String() string {
+	return fmt.Sprintf("%s_%s", s.Kind, s.Version)
+}
+
+// Valid checks if this SdkSpec is well-formed. Note however that true doesn't mean that the
+// specified SDK actually exists.
+func (s SdkSpec) Valid() bool {
+	return s.Kind != SdkInvalid
+}
+
+// Specified checks if this SdkSpec is well-formed and is not "".
+func (s SdkSpec) Specified() bool {
+	return s.Valid() && s.Kind != SdkPrivate
+}
+
+// whether the API surface is managed and versioned, i.e. has .txt file that
+// get frozen on SDK freeze and changes get reviewed by API council.
+func (s SdkSpec) Stable() bool {
+	if !s.Specified() {
+		return false
+	}
+	switch s.Kind {
+	case SdkNone:
+		// there is nothing to manage and version in this case; de facto stable API.
+		return true
+	case SdkCore, SdkPublic, SdkSystem, SdkModule, SdkSystemServer:
+		return true
+	case SdkCorePlatform, SdkTest, SdkPrivate:
+		return false
+	default:
+		panic(fmt.Errorf("unknown SdkKind=%v", s.Kind))
+	}
+	return false
+}
+
+// PrebuiltSdkAvailableForUnbundledBuilt tells whether this SdkSpec can have a prebuilt SDK
+// that can be used for unbundled builds.
+func (s SdkSpec) PrebuiltSdkAvailableForUnbundledBuild() bool {
+	// "", "none", and "core_platform" are not available for unbundled build
+	// as we don't/can't have prebuilt stub for the versions
+	return s.Kind != SdkPrivate && s.Kind != SdkNone && s.Kind != SdkCorePlatform
+}
+
+func (s SdkSpec) ForVendorPartition(ctx EarlyModuleContext) SdkSpec {
+	// If BOARD_CURRENT_API_LEVEL_FOR_VENDOR_MODULES has a numeric value,
+	// use it instead of "current" for the vendor partition.
+	currentSdkVersion := ctx.DeviceConfig().CurrentApiLevelForVendorModules()
+	if currentSdkVersion == "current" {
+		return s
+	}
+
+	if s.Kind == SdkPublic || s.Kind == SdkSystem {
+		if s.Version.IsCurrent() {
+			if i, err := strconv.Atoi(currentSdkVersion); err == nil {
+				version := SdkVersion(i)
+				return SdkSpec{s.Kind, version, s.Raw}
+			}
+			panic(fmt.Errorf("BOARD_CURRENT_API_LEVEL_FOR_VENDOR_MODULES must be either \"current\" or a number, but was %q", currentSdkVersion))
+		}
+	}
+	return s
+}
+
+// UsePrebuilt determines whether prebuilt SDK should be used for this SdkSpec with the given context.
+func (s SdkSpec) UsePrebuilt(ctx EarlyModuleContext) bool {
+	if s.Version.IsCurrent() {
+		// "current" can be built from source and be from prebuilt SDK
+		return ctx.Config().AlwaysUsePrebuiltSdks()
+	} else if s.Version.IsNumbered() {
+		// validation check
+		if s.Kind != SdkPublic && s.Kind != SdkSystem && s.Kind != SdkTest && s.Kind != SdkModule {
+			panic(fmt.Errorf("prebuilt SDK is not not available for SdkKind=%q", s.Kind))
+			return false
+		}
+		// numbered SDKs are always from prebuilt
+		return true
+	}
+	// "", "none", "core_platform" fall here
+	return false
+}
+
+// EffectiveVersion converts an SdkSpec into the concrete SdkVersion that the module
+// should use. For modules targeting an unreleased SDK (meaning it does not yet have a number)
+// it returns FutureApiLevel(10000).
+func (s SdkSpec) EffectiveVersion(ctx EarlyModuleContext) (SdkVersion, error) {
+	if !s.Valid() {
+		return s.Version, fmt.Errorf("invalid sdk version %q", s.Raw)
+	}
+
+	if ctx.DeviceSpecific() || ctx.SocSpecific() {
+		s = s.ForVendorPartition(ctx)
+	}
+	if s.Version.IsNumbered() {
+		return s.Version, nil
+	}
+	return SdkVersion(ctx.Config().DefaultAppTargetSdk(ctx).FinalOrFutureInt()), nil
+}
+
+// EffectiveVersionString converts an SdkSpec into the concrete version string that the module
+// should use. For modules targeting an unreleased SDK (meaning it does not yet have a number)
+// it returns the codename (P, Q, R, etc.)
+func (s SdkSpec) EffectiveVersionString(ctx EarlyModuleContext) (string, error) {
+	ver, err := s.EffectiveVersion(ctx)
+	if err == nil && int(ver) == ctx.Config().DefaultAppTargetSdk(ctx).FinalOrFutureInt() {
+		return ctx.Config().DefaultAppTargetSdk(ctx).String(), nil
+	}
+	return ver.String(), err
+}
+
+func SdkSpecFrom(str string) SdkSpec {
+	switch str {
+	// special cases first
+	case "":
+		return SdkSpec{SdkPrivate, SdkVersionNone, str}
+	case "none":
+		return SdkSpec{SdkNone, SdkVersionNone, str}
+	case "core_platform":
+		return SdkSpec{SdkCorePlatform, SdkVersionNone, str}
+	default:
+		// the syntax is [kind_]version
+		sep := strings.LastIndex(str, "_")
+
+		var kindString string
+		if sep == 0 {
+			return SdkSpec{SdkInvalid, SdkVersionNone, str}
+		} else if sep == -1 {
+			kindString = ""
+		} else {
+			kindString = str[0:sep]
+		}
+		versionString := str[sep+1 : len(str)]
+
+		var kind SdkKind
+		switch kindString {
+		case "":
+			kind = SdkPublic
+		case "core":
+			kind = SdkCore
+		case "system":
+			kind = SdkSystem
+		case "test":
+			kind = SdkTest
+		case "module":
+			kind = SdkModule
+		case "system_server":
+			kind = SdkSystemServer
+		default:
+			return SdkSpec{SdkInvalid, SdkVersionNone, str}
+		}
+
+		var version SdkVersion
+		if versionString == "current" {
+			version = SdkVersionCurrent
+		} else if i, err := strconv.Atoi(versionString); err == nil {
+			version = SdkVersion(i)
+		} else {
+			return SdkSpec{SdkInvalid, SdkVersionNone, str}
+		}
+
+		return SdkSpec{kind, version, str}
+	}
+}
+
+func (s SdkSpec) ValidateSystemSdk(ctx EarlyModuleContext) bool {
+	// Ensures that the specified system SDK version is one of BOARD_SYSTEMSDK_VERSIONS (for vendor/product Java module)
+	// Assuming that BOARD_SYSTEMSDK_VERSIONS := 28 29,
+	// sdk_version of the modules in vendor/product that use system sdk must be either system_28, system_29 or system_current
+	if s.Kind != SdkSystem || !s.Version.IsNumbered() {
+		return true
+	}
+	allowedVersions := ctx.DeviceConfig().PlatformSystemSdkVersions()
+	if ctx.DeviceSpecific() || ctx.SocSpecific() || (ctx.ProductSpecific() && ctx.Config().EnforceProductPartitionInterface()) {
+		systemSdkVersions := ctx.DeviceConfig().SystemSdkVersions()
+		if len(systemSdkVersions) > 0 {
+			allowedVersions = systemSdkVersions
+		}
+	}
+	if len(allowedVersions) > 0 && !InList(s.Version.String(), allowedVersions) {
+		ctx.PropertyErrorf("sdk_version", "incompatible sdk version %q. System SDK version should be one of %q",
+			s.Raw, allowedVersions)
+		return false
+	}
+	return true
+}
diff --git a/apex/builder.go b/apex/builder.go
index da800d4..2df380b 100644
--- a/apex/builder.go
+++ b/apex/builder.go
@@ -950,6 +950,10 @@
 				if v := m.MinSdkVersion(); v != "" {
 					toMinSdkVersion = v
 				}
+			} else if m, ok := to.(interface{ MinSdkVersionString() string }); ok {
+				if v := m.MinSdkVersionString(); v != "" {
+					toMinSdkVersion = v
+				}
 			}
 
 			depInfos[to.Name()] = android.ApexModuleDepInfo{
diff --git a/bazel/aquery.go b/bazel/aquery.go
index c82b464..555f1dc 100644
--- a/bazel/aquery.go
+++ b/bazel/aquery.go
@@ -74,6 +74,7 @@
 // with a Bazel action from Bazel's action graph.
 type BuildStatement struct {
 	Command     string
+	Depfile     *string
 	OutputPaths []string
 	InputPaths  []string
 	Env         []KeyValuePair
@@ -133,12 +134,22 @@
 			continue
 		}
 		outputPaths := []string{}
+		var depfile *string
 		for _, outputId := range actionEntry.OutputIds {
 			outputPath, exists := artifactIdToPath[outputId]
 			if !exists {
 				return nil, fmt.Errorf("undefined outputId %d", outputId)
 			}
-			outputPaths = append(outputPaths, outputPath)
+			ext := filepath.Ext(outputPath)
+			if ext == ".d" {
+				if depfile != nil {
+					return nil, fmt.Errorf("found multiple potential depfiles %q, %q", *depfile, outputPath)
+				} else {
+					depfile = &outputPath
+				}
+			} else {
+				outputPaths = append(outputPaths, outputPath)
+			}
 		}
 		inputPaths := []string{}
 		for _, inputDepSetId := range actionEntry.InputDepSetIds {
@@ -161,12 +172,13 @@
 		}
 		buildStatement := BuildStatement{
 			Command:     strings.Join(proptools.ShellEscapeList(actionEntry.Arguments), " "),
+			Depfile:     depfile,
 			OutputPaths: outputPaths,
 			InputPaths:  inputPaths,
 			Env:         actionEntry.EnvironmentVariables,
 			Mnemonic:    actionEntry.Mnemonic}
 		if len(actionEntry.Arguments) < 1 {
-			return nil, fmt.Errorf("received action with no command: [%s]", buildStatement)
+			return nil, fmt.Errorf("received action with no command: [%v]", buildStatement)
 			continue
 		}
 		buildStatements = append(buildStatements, buildStatement)
diff --git a/bazel/aquery_test.go b/bazel/aquery_test.go
index a48e083..fa8810f 100644
--- a/bazel/aquery_test.go
+++ b/bazel/aquery_test.go
@@ -393,6 +393,109 @@
 	assertError(t, err, "undefined path fragment id 3")
 }
 
+func TestDepfiles(t *testing.T) {
+	const inputString = `
+{
+  "artifacts": [{
+    "id": 1,
+    "pathFragmentId": 1
+  }, {
+    "id": 2,
+    "pathFragmentId": 2
+  }, {
+    "id": 3,
+    "pathFragmentId": 3
+  }],
+  "actions": [{
+    "targetId": 1,
+    "actionKey": "x",
+    "mnemonic": "x",
+    "arguments": ["touch", "foo"],
+    "inputDepSetIds": [1],
+    "outputIds": [2, 3],
+    "primaryOutputId": 2
+  }],
+  "depSetOfFiles": [{
+    "id": 1,
+    "directArtifactIds": [1, 2, 3]
+  }],
+  "pathFragments": [{
+    "id": 1,
+    "label": "one"
+  }, {
+    "id": 2,
+    "label": "two"
+  }, {
+    "id": 3,
+    "label": "two.d"
+  }]
+}`
+
+	actual, err := AqueryBuildStatements([]byte(inputString))
+	if err != nil {
+		t.Errorf("Unexpected error %q", err)
+	}
+	if expected := 1; len(actual) != expected {
+		t.Fatalf("Expected %d build statements, got %d", expected, len(actual))
+	}
+
+	bs := actual[0]
+	expectedDepfile := "two.d"
+	if bs.Depfile == nil {
+		t.Errorf("Expected depfile %q, but there was none found", expectedDepfile)
+	} else if *bs.Depfile != expectedDepfile {
+		t.Errorf("Expected depfile %q, but got %q", expectedDepfile, *bs.Depfile)
+	}
+}
+
+func TestMultipleDepfiles(t *testing.T) {
+	const inputString = `
+{
+  "artifacts": [{
+    "id": 1,
+    "pathFragmentId": 1
+  }, {
+    "id": 2,
+    "pathFragmentId": 2
+  }, {
+    "id": 3,
+    "pathFragmentId": 3
+  }, {
+    "id": 4,
+    "pathFragmentId": 4
+  }],
+  "actions": [{
+    "targetId": 1,
+    "actionKey": "x",
+    "mnemonic": "x",
+    "arguments": ["touch", "foo"],
+    "inputDepSetIds": [1],
+    "outputIds": [2,3,4],
+    "primaryOutputId": 2
+  }],
+  "depSetOfFiles": [{
+    "id": 1,
+    "directArtifactIds": [1, 2, 3, 4]
+  }],
+  "pathFragments": [{
+    "id": 1,
+    "label": "one"
+  }, {
+    "id": 2,
+    "label": "two"
+  }, {
+    "id": 3,
+    "label": "two.d"
+  }, {
+    "id": 4,
+    "label": "other.d"
+  }]
+}`
+
+	_, err := AqueryBuildStatements([]byte(inputString))
+	assertError(t, err, `found multiple potential depfiles "two.d", "other.d"`)
+}
+
 func TestTransitiveInputDepsets(t *testing.T) {
 	// The input aquery for this test comes from a proof-of-concept starlark rule which registers
 	// a single action with many inputs given via a deep depset.
@@ -627,7 +730,7 @@
 // Build statement equivalence is determined using buildStatementEquals.
 func assertBuildStatements(t *testing.T, expected []BuildStatement, actual []BuildStatement) {
 	if len(expected) != len(actual) {
-		t.Errorf("expected %d build statements, but got %d,\n expected: %s,\n actual: %s",
+		t.Errorf("expected %d build statements, but got %d,\n expected: %v,\n actual: %v",
 			len(expected), len(actual), expected, actual)
 		return
 	}
@@ -638,7 +741,7 @@
 				continue ACTUAL_LOOP
 			}
 		}
-		t.Errorf("unexpected build statement %s.\n expected: %s",
+		t.Errorf("unexpected build statement %v.\n expected: %v",
 			actualStatement, expected)
 		return
 	}
diff --git a/bazel/cquery/request_type.go b/bazel/cquery/request_type.go
index 864db3d..bd1ece1 100644
--- a/bazel/cquery/request_type.go
+++ b/bazel/cquery/request_type.go
@@ -6,7 +6,6 @@
 
 var (
 	GetOutputFiles                 RequestType = &getOutputFilesRequestType{}
-	GetCcObjectFiles               RequestType = &getCcObjectFilesRequestType{}
 	GetOutputFilesAndCcObjectFiles RequestType = &getOutputFilesAndCcObjectFilesType{}
 )
 
@@ -16,7 +15,9 @@
 }
 
 var RequestTypes []RequestType = []RequestType{
-	GetOutputFiles, GetCcObjectFiles, GetOutputFilesAndCcObjectFiles}
+	GetOutputFiles,
+	GetOutputFilesAndCcObjectFiles,
+}
 
 type RequestType interface {
 	// Name returns a string name for this request type. Such request type names must be unique,
@@ -55,28 +56,6 @@
 	return strings.Split(rawString, ", ")
 }
 
-type getCcObjectFilesRequestType struct{}
-
-func (g getCcObjectFilesRequestType) Name() string {
-	return "getCcObjectFiles"
-}
-
-func (g getCcObjectFilesRequestType) StarlarkFunctionBody() string {
-	return `
-result = []
-linker_inputs = providers(target)["CcInfo"].linking_context.linker_inputs.to_list()
-
-for linker_input in linker_inputs:
-  for library in linker_input.libraries:
-    for object in library.objects:
-      result += [object.path]
-return ', '.join(result)`
-}
-
-func (g getCcObjectFilesRequestType) ParseResult(rawString string) interface{} {
-	return strings.Split(rawString, ", ")
-}
-
 type getOutputFilesAndCcObjectFilesType struct{}
 
 func (g getOutputFilesAndCcObjectFilesType) Name() string {
diff --git a/bazel/properties.go b/bazel/properties.go
index 1763f2d..250fea4 100644
--- a/bazel/properties.go
+++ b/bazel/properties.go
@@ -80,10 +80,19 @@
 }
 
 const (
-	ARCH_X86    = "x86"
-	ARCH_X86_64 = "x86_64"
+	// ArchType names in arch.go
 	ARCH_ARM    = "arm"
 	ARCH_ARM64  = "arm64"
+	ARCH_X86    = "x86"
+	ARCH_X86_64 = "x86_64"
+
+	// OsType names in arch.go
+	OS_ANDROID      = "android"
+	OS_DARWIN       = "darwin"
+	OS_FUCHSIA      = "fuchsia"
+	OS_LINUX        = "linux_glibc"
+	OS_LINUX_BIONIC = "linux_bionic"
+	OS_WINDOWS      = "windows"
 )
 
 var (
@@ -92,6 +101,36 @@
 	// android package depends on the bazel package, so a cyclic dependency
 	// prevents using that here.
 	selectableArchs = []string{ARCH_X86, ARCH_X86_64, ARCH_ARM, ARCH_ARM64}
+
+	// Likewise, this is the list of target operating systems.
+	selectableTargetOs = []string{
+		OS_ANDROID,
+		OS_DARWIN,
+		OS_FUCHSIA,
+		OS_LINUX,
+		OS_LINUX_BIONIC,
+		OS_WINDOWS,
+	}
+
+	// A map of architectures to the Bazel label of the constraint_value
+	// for the @platforms//cpu:cpu constraint_setting
+	PlatformArchMap = map[string]string{
+		ARCH_ARM:    "//build/bazel/platforms/arch:arm",
+		ARCH_ARM64:  "//build/bazel/platforms/arch:arm64",
+		ARCH_X86:    "//build/bazel/platforms/arch:x86",
+		ARCH_X86_64: "//build/bazel/platforms/arch:x86_64",
+	}
+
+	// A map of target operating systems to the Bazel label of the
+	// constraint_value for the @platforms//os:os constraint_setting
+	PlatformOsMap = map[string]string{
+		OS_ANDROID:      "//build/bazel/platforms/os:android",
+		OS_DARWIN:       "//build/bazel/platforms/os:darwin",
+		OS_FUCHSIA:      "//build/bazel/platforms/os:fuchsia",
+		OS_LINUX:        "//build/bazel/platforms/os:linux",
+		OS_LINUX_BIONIC: "//build/bazel/platforms/os:linux_bionic",
+		OS_WINDOWS:      "//build/bazel/platforms/os:windows",
+	}
 )
 
 // Arch-specific label_list typed Bazel attribute values. This should correspond
@@ -101,8 +140,16 @@
 	X86_64 LabelList
 	Arm    LabelList
 	Arm64  LabelList
-	// TODO(b/181299724): this is currently missing the "common" arch, which
-	// doesn't have an equivalent platform() definition yet.
+	Common LabelList
+}
+
+type labelListOsValues struct {
+	Android     LabelList
+	Darwin      LabelList
+	Fuchsia     LabelList
+	Linux       LabelList
+	LinuxBionic LabelList
+	Windows     LabelList
 }
 
 // LabelListAttribute is used to represent a list of Bazel labels as an
@@ -115,6 +162,11 @@
 	// are generated in a select statement and appended to the non-arch specific
 	// label list Value.
 	ArchValues labelListArchValues
+
+	// The os-specific attribute label list values. Optional. If used, these
+	// are generated in a select statement and appended to the non-os specific
+	// label list Value.
+	OsValues labelListOsValues
 }
 
 // MakeLabelListAttribute initializes a LabelListAttribute with the non-arch specific value.
@@ -124,45 +176,75 @@
 
 // HasArchSpecificValues returns true if the attribute contains
 // architecture-specific label_list values.
-func (attrs *LabelListAttribute) HasArchSpecificValues() bool {
+func (attrs *LabelListAttribute) HasConfigurableValues() bool {
 	for _, arch := range selectableArchs {
-		if len(attrs.GetValueForArch(arch).Includes) > 0 || len(attrs.GetValueForArch(arch).Excludes) > 0 {
+		if len(attrs.GetValueForArch(arch).Includes) > 0 {
+			return true
+		}
+	}
+
+	for _, os := range selectableTargetOs {
+		if len(attrs.GetValueForOS(os).Includes) > 0 {
 			return true
 		}
 	}
 	return false
 }
 
+func (attrs *LabelListAttribute) archValuePtrs() map[string]*LabelList {
+	return map[string]*LabelList{
+		ARCH_X86:    &attrs.ArchValues.X86,
+		ARCH_X86_64: &attrs.ArchValues.X86_64,
+		ARCH_ARM:    &attrs.ArchValues.Arm,
+		ARCH_ARM64:  &attrs.ArchValues.Arm64,
+	}
+}
+
 // GetValueForArch returns the label_list attribute value for an architecture.
 func (attrs *LabelListAttribute) GetValueForArch(arch string) LabelList {
-	switch arch {
-	case ARCH_X86:
-		return attrs.ArchValues.X86
-	case ARCH_X86_64:
-		return attrs.ArchValues.X86_64
-	case ARCH_ARM:
-		return attrs.ArchValues.Arm
-	case ARCH_ARM64:
-		return attrs.ArchValues.Arm64
-	default:
+	var v *LabelList
+	if v = attrs.archValuePtrs()[arch]; v == nil {
 		panic(fmt.Errorf("Unknown arch: %s", arch))
 	}
+	return *v
 }
 
 // SetValueForArch sets the label_list attribute value for an architecture.
 func (attrs *LabelListAttribute) SetValueForArch(arch string, value LabelList) {
-	switch arch {
-	case "x86":
-		attrs.ArchValues.X86 = value
-	case "x86_64":
-		attrs.ArchValues.X86_64 = value
-	case "arm":
-		attrs.ArchValues.Arm = value
-	case "arm64":
-		attrs.ArchValues.Arm64 = value
-	default:
+	var v *LabelList
+	if v = attrs.archValuePtrs()[arch]; v == nil {
 		panic(fmt.Errorf("Unknown arch: %s", arch))
 	}
+	*v = value
+}
+
+func (attrs *LabelListAttribute) osValuePtrs() map[string]*LabelList {
+	return map[string]*LabelList{
+		OS_ANDROID:      &attrs.OsValues.Android,
+		OS_DARWIN:       &attrs.OsValues.Darwin,
+		OS_FUCHSIA:      &attrs.OsValues.Fuchsia,
+		OS_LINUX:        &attrs.OsValues.Linux,
+		OS_LINUX_BIONIC: &attrs.OsValues.LinuxBionic,
+		OS_WINDOWS:      &attrs.OsValues.Windows,
+	}
+}
+
+// GetValueForOS returns the label_list attribute value for an OS target.
+func (attrs *LabelListAttribute) GetValueForOS(os string) LabelList {
+	var v *LabelList
+	if v = attrs.osValuePtrs()[os]; v == nil {
+		panic(fmt.Errorf("Unknown os: %s", os))
+	}
+	return *v
+}
+
+// SetValueForArch sets the label_list attribute value for an OS target.
+func (attrs *LabelListAttribute) SetValueForOS(os string, value LabelList) {
+	var v *LabelList
+	if v = attrs.osValuePtrs()[os]; v == nil {
+		panic(fmt.Errorf("Unknown os: %s", os))
+	}
+	*v = value
 }
 
 // StringListAttribute corresponds to the string_list Bazel attribute type with
@@ -182,13 +264,12 @@
 	X86_64 []string
 	Arm    []string
 	Arm64  []string
-	// TODO(b/181299724): this is currently missing the "common" arch, which
-	// doesn't have an equivalent platform() definition yet.
+	Common []string
 }
 
-// HasArchSpecificValues returns true if the attribute contains
+// HasConfigurableValues returns true if the attribute contains
 // architecture-specific string_list values.
-func (attrs *StringListAttribute) HasArchSpecificValues() bool {
+func (attrs *StringListAttribute) HasConfigurableValues() bool {
 	for _, arch := range selectableArchs {
 		if len(attrs.GetValueForArch(arch)) > 0 {
 			return true
@@ -197,36 +278,31 @@
 	return false
 }
 
+func (attrs *StringListAttribute) archValuePtrs() map[string]*[]string {
+	return map[string]*[]string{
+		ARCH_X86:    &attrs.ArchValues.X86,
+		ARCH_X86_64: &attrs.ArchValues.X86_64,
+		ARCH_ARM:    &attrs.ArchValues.Arm,
+		ARCH_ARM64:  &attrs.ArchValues.Arm64,
+	}
+}
+
 // GetValueForArch returns the string_list attribute value for an architecture.
 func (attrs *StringListAttribute) GetValueForArch(arch string) []string {
-	switch arch {
-	case ARCH_X86:
-		return attrs.ArchValues.X86
-	case ARCH_X86_64:
-		return attrs.ArchValues.X86_64
-	case ARCH_ARM:
-		return attrs.ArchValues.Arm
-	case ARCH_ARM64:
-		return attrs.ArchValues.Arm64
-	default:
+	var v *[]string
+	if v = attrs.archValuePtrs()[arch]; v == nil {
 		panic(fmt.Errorf("Unknown arch: %s", arch))
 	}
+	return *v
 }
 
 // SetValueForArch sets the string_list attribute value for an architecture.
 func (attrs *StringListAttribute) SetValueForArch(arch string, value []string) {
-	switch arch {
-	case ARCH_X86:
-		attrs.ArchValues.X86 = value
-	case ARCH_X86_64:
-		attrs.ArchValues.X86_64 = value
-	case ARCH_ARM:
-		attrs.ArchValues.Arm = value
-	case ARCH_ARM64:
-		attrs.ArchValues.Arm64 = value
-	default:
+	var v *[]string
+	if v = attrs.archValuePtrs()[arch]; v == nil {
 		panic(fmt.Errorf("Unknown arch: %s", arch))
 	}
+	*v = value
 }
 
 // TryVariableSubstitution, replace string substitution formatting within each string in slice with
diff --git a/bp2build/build_conversion.go b/bp2build/build_conversion.go
index e93b3dc..1d254c8 100644
--- a/bp2build/build_conversion.go
+++ b/bp2build/build_conversion.go
@@ -416,63 +416,11 @@
 		// Special cases where the bp2build sends additional information to the codegenerator
 		// by wrapping the attributes in a custom struct type.
 		if labels, ok := propertyValue.Interface().(bazel.LabelListAttribute); ok {
-			// TODO(b/165114590): convert glob syntax
-			ret, err := prettyPrint(reflect.ValueOf(labels.Value.Includes), indent)
-			if err != nil {
-				return ret, err
-			}
-
-			if !labels.HasArchSpecificValues() {
-				// Select statement not needed.
-				return ret, nil
-			}
-
-			ret += " + " + "select({\n"
-			for _, arch := range android.ArchTypeList() {
-				value := labels.GetValueForArch(arch.Name)
-				if len(value.Includes) > 0 {
-					ret += makeIndent(indent + 1)
-					list, _ := prettyPrint(reflect.ValueOf(value.Includes), indent+1)
-					ret += fmt.Sprintf("\"%s\": %s,\n", platformArchMap[arch], list)
-				}
-			}
-
-			ret += makeIndent(indent + 1)
-			ret += fmt.Sprintf("\"%s\": [],\n", "//conditions:default")
-
-			ret += makeIndent(indent)
-			ret += "})"
-			return ret, err
+			return prettyPrintLabelListAttribute(labels, indent)
 		} else if label, ok := propertyValue.Interface().(bazel.Label); ok {
 			return fmt.Sprintf("%q", label.Label), nil
 		} else if stringList, ok := propertyValue.Interface().(bazel.StringListAttribute); ok {
-			// A Bazel string_list attribute that may contain a select statement.
-			ret, err := prettyPrint(reflect.ValueOf(stringList.Value), indent)
-			if err != nil {
-				return ret, err
-			}
-
-			if !stringList.HasArchSpecificValues() {
-				// Select statement not needed.
-				return ret, nil
-			}
-
-			ret += " + " + "select({\n"
-			for _, arch := range android.ArchTypeList() {
-				value := stringList.GetValueForArch(arch.Name)
-				if len(value) > 0 {
-					ret += makeIndent(indent + 1)
-					list, _ := prettyPrint(reflect.ValueOf(value), indent+1)
-					ret += fmt.Sprintf("\"%s\": %s,\n", platformArchMap[arch], list)
-				}
-			}
-
-			ret += makeIndent(indent + 1)
-			ret += fmt.Sprintf("\"%s\": [],\n", "//conditions:default")
-
-			ret += makeIndent(indent)
-			ret += "})"
-			return ret, err
+			return prettyPrintStringListAttribute(stringList, indent)
 		}
 
 		ret = "{\n"
diff --git a/bp2build/cc_library_headers_conversion_test.go b/bp2build/cc_library_headers_conversion_test.go
index 049f84a..d828168 100644
--- a/bp2build/cc_library_headers_conversion_test.go
+++ b/bp2build/cc_library_headers_conversion_test.go
@@ -110,13 +110,11 @@
 cc_library_headers {
     name: "lib-1",
     export_include_dirs: ["lib-1"],
-    bazel_module: { bp2build_available: true },
 }
 
 cc_library_headers {
     name: "lib-2",
     export_include_dirs: ["lib-2"],
-    bazel_module: { bp2build_available: true },
 }
 
 cc_library_headers {
@@ -125,7 +123,6 @@
     header_libs: ["lib-1", "lib-2"],
 
     // TODO: Also support export_header_lib_headers
-    bazel_module: { bp2build_available: true },
 }`,
 			expectedBazelTargets: []string{`cc_library_headers(
     name = "foo_headers",
@@ -163,6 +160,106 @@
     ],
 )`},
 		},
+		{
+			description:                        "cc_library_headers test with os-specific header_libs props",
+			moduleTypeUnderTest:                "cc_library_headers",
+			moduleTypeUnderTestFactory:         cc.LibraryHeaderFactory,
+			moduleTypeUnderTestBp2BuildMutator: cc.CcLibraryHeadersBp2Build,
+			depsMutators:                       []android.RegisterMutatorFunc{cc.RegisterDepsBp2Build},
+			filesystem:                         map[string]string{},
+			bp: soongCcLibraryPreamble + `
+cc_library_headers { name: "android-lib" }
+cc_library_headers { name: "base-lib" }
+cc_library_headers { name: "darwin-lib" }
+cc_library_headers { name: "fuchsia-lib" }
+cc_library_headers { name: "linux-lib" }
+cc_library_headers { name: "linux_bionic-lib" }
+cc_library_headers { name: "windows-lib" }
+cc_library_headers {
+    name: "foo_headers",
+    header_libs: ["base-lib"],
+    target: {
+        android: { header_libs: ["android-lib"] },
+        darwin: { header_libs: ["darwin-lib"] },
+        fuchsia: { header_libs: ["fuchsia-lib"] },
+        linux_bionic: { header_libs: ["linux_bionic-lib"] },
+        linux_glibc: { header_libs: ["linux-lib"] },
+        windows: { header_libs: ["windows-lib"] },
+    },
+    bazel_module: { bp2build_available: true },
+}`,
+			expectedBazelTargets: []string{`cc_library_headers(
+    name = "android-lib",
+)`, `cc_library_headers(
+    name = "base-lib",
+)`, `cc_library_headers(
+    name = "darwin-lib",
+)`, `cc_library_headers(
+    name = "foo_headers",
+    deps = [
+        ":base-lib",
+    ] + select({
+        "//build/bazel/platforms/os:android": [
+            ":android-lib",
+        ],
+        "//build/bazel/platforms/os:darwin": [
+            ":darwin-lib",
+        ],
+        "//build/bazel/platforms/os:fuchsia": [
+            ":fuchsia-lib",
+        ],
+        "//build/bazel/platforms/os:linux": [
+            ":linux-lib",
+        ],
+        "//build/bazel/platforms/os:linux_bionic": [
+            ":linux_bionic-lib",
+        ],
+        "//build/bazel/platforms/os:windows": [
+            ":windows-lib",
+        ],
+        "//conditions:default": [],
+    }),
+)`, `cc_library_headers(
+    name = "fuchsia-lib",
+)`, `cc_library_headers(
+    name = "linux-lib",
+)`, `cc_library_headers(
+    name = "linux_bionic-lib",
+)`, `cc_library_headers(
+    name = "windows-lib",
+)`},
+		},
+		{
+			description:                        "cc_library_headers test with os-specific header_libs and export_header_lib_headers props",
+			moduleTypeUnderTest:                "cc_library_headers",
+			moduleTypeUnderTestFactory:         cc.LibraryHeaderFactory,
+			moduleTypeUnderTestBp2BuildMutator: cc.CcLibraryHeadersBp2Build,
+			depsMutators:                       []android.RegisterMutatorFunc{cc.RegisterDepsBp2Build},
+			filesystem:                         map[string]string{},
+			bp: soongCcLibraryPreamble + `
+cc_library_headers { name: "android-lib" }
+cc_library_headers { name: "exported-lib" }
+cc_library_headers {
+    name: "foo_headers",
+    target: {
+        android: { header_libs: ["android-lib"], export_header_lib_headers: ["exported-lib"] },
+    },
+}`,
+			expectedBazelTargets: []string{`cc_library_headers(
+    name = "android-lib",
+)`, `cc_library_headers(
+    name = "exported-lib",
+)`, `cc_library_headers(
+    name = "foo_headers",
+    deps = [] + select({
+        "//build/bazel/platforms/os:android": [
+            ":android-lib",
+            ":exported-lib",
+        ],
+        "//conditions:default": [],
+    }),
+)`},
+		},
 	}
 
 	dir := "."
@@ -180,6 +277,9 @@
 		config := android.TestConfig(buildDir, nil, testCase.bp, filesystem)
 		ctx := android.NewTestContext(config)
 
+		// TODO(jingwen): make this default for all bp2build tests
+		ctx.RegisterBp2BuildConfig(bp2buildConfig)
+
 		cc.RegisterCCBuildComponents(ctx)
 		ctx.RegisterModuleType("toolchain_library", cc.ToolchainLibraryFactory)
 
diff --git a/bp2build/cc_object_conversion_test.go b/bp2build/cc_object_conversion_test.go
index 9461739..fcc3080 100644
--- a/bp2build/cc_object_conversion_test.go
+++ b/bp2build/cc_object_conversion_test.go
@@ -324,7 +324,7 @@
     copts = [
         "-fno-addrsig",
     ] + select({
-        "@bazel_tools//platforms:x86_32": [
+        "//build/bazel/platforms/arch:x86": [
             "-fPIC",
         ],
         "//conditions:default": [],
@@ -335,7 +335,7 @@
     srcs = [
         "a.cpp",
     ] + select({
-        "@bazel_tools//platforms:arm": [
+        "//build/bazel/platforms/arch:arm": [
             "arch/arm/file.S",
         ],
         "//conditions:default": [],
@@ -378,16 +378,16 @@
     copts = [
         "-fno-addrsig",
     ] + select({
-        "@bazel_tools//platforms:arm": [
+        "//build/bazel/platforms/arch:arm": [
             "-Wall",
         ],
-        "@bazel_tools//platforms:aarch64": [
+        "//build/bazel/platforms/arch:arm64": [
             "-Wall",
         ],
-        "@bazel_tools//platforms:x86_32": [
+        "//build/bazel/platforms/arch:x86": [
             "-fPIC",
         ],
-        "@bazel_tools//platforms:x86_64": [
+        "//build/bazel/platforms/arch:x86_64": [
             "-fPIC",
         ],
         "//conditions:default": [],
@@ -398,16 +398,16 @@
     srcs = [
         "base.cpp",
     ] + select({
-        "@bazel_tools//platforms:arm": [
+        "//build/bazel/platforms/arch:arm": [
             "arm.cpp",
         ],
-        "@bazel_tools//platforms:aarch64": [
+        "//build/bazel/platforms/arch:arm64": [
             "arm64.cpp",
         ],
-        "@bazel_tools//platforms:x86_32": [
+        "//build/bazel/platforms/arch:x86": [
             "x86.cpp",
         ],
-        "@bazel_tools//platforms:x86_64": [
+        "//build/bazel/platforms/arch:x86_64": [
             "x86_64.cpp",
         ],
         "//conditions:default": [],
diff --git a/bp2build/configurability.go b/bp2build/configurability.go
index 47cf3c6..6ca0d6d 100644
--- a/bp2build/configurability.go
+++ b/bp2build/configurability.go
@@ -1,15 +1,112 @@
 package bp2build
 
-import "android/soong/android"
+import (
+	"android/soong/android"
+	"android/soong/bazel"
+	"fmt"
+	"reflect"
+)
 
 // Configurability support for bp2build.
 
-var (
-	// A map of architectures to the Bazel label of the constraint_value.
-	platformArchMap = map[android.ArchType]string{
-		android.Arm:    "@bazel_tools//platforms:arm",
-		android.Arm64:  "@bazel_tools//platforms:aarch64",
-		android.X86:    "@bazel_tools//platforms:x86_32",
-		android.X86_64: "@bazel_tools//platforms:x86_64",
+// prettyPrintStringListAttribute converts a StringListAttribute to its Bazel
+// syntax. May contain a select statement.
+func prettyPrintStringListAttribute(stringList bazel.StringListAttribute, indent int) (string, error) {
+	ret, err := prettyPrint(reflect.ValueOf(stringList.Value), indent)
+	if err != nil {
+		return ret, err
 	}
-)
+
+	if !stringList.HasConfigurableValues() {
+		// Select statement not needed.
+		return ret, nil
+	}
+
+	// Create the selects for arch specific values.
+	selects := map[string]reflect.Value{}
+	for arch, selectKey := range bazel.PlatformArchMap {
+		selects[selectKey] = reflect.ValueOf(stringList.GetValueForArch(arch))
+	}
+
+	selectMap, err := prettyPrintSelectMap(selects, "[]", indent)
+	return ret + selectMap, err
+}
+
+// prettyPrintLabelListAttribute converts a LabelListAttribute to its Bazel
+// syntax. May contain select statements.
+func prettyPrintLabelListAttribute(labels bazel.LabelListAttribute, indent int) (string, error) {
+	// TODO(b/165114590): convert glob syntax
+	ret, err := prettyPrint(reflect.ValueOf(labels.Value.Includes), indent)
+	if err != nil {
+		return ret, err
+	}
+
+	if !labels.HasConfigurableValues() {
+		// Select statements not needed.
+		return ret, nil
+	}
+
+	// Create the selects for arch specific values.
+	archSelects := map[string]reflect.Value{}
+	for arch, selectKey := range bazel.PlatformArchMap {
+		archSelects[selectKey] = reflect.ValueOf(labels.GetValueForArch(arch).Includes)
+	}
+	selectMap, err := prettyPrintSelectMap(archSelects, "[]", indent)
+	if err != nil {
+		return "", err
+	}
+	ret += selectMap
+
+	// Create the selects for target os specific values.
+	osSelects := map[string]reflect.Value{}
+	for os, selectKey := range bazel.PlatformOsMap {
+		osSelects[selectKey] = reflect.ValueOf(labels.GetValueForOS(os).Includes)
+	}
+	selectMap, err = prettyPrintSelectMap(osSelects, "[]", indent)
+	return ret + selectMap, err
+}
+
+// prettyPrintSelectMap converts a map of select keys to reflected Values as a generic way
+// to construct a select map for any kind of attribute type.
+func prettyPrintSelectMap(selectMap map[string]reflect.Value, defaultValue string, indent int) (string, error) {
+	var selects string
+	for _, selectKey := range android.SortedStringKeys(selectMap) {
+		value := selectMap[selectKey]
+		if isZero(value) {
+			// Ignore zero values to not generate empty lists.
+			continue
+		}
+		s, err := prettyPrintSelectEntry(value, selectKey, indent)
+		if err != nil {
+			return "", err
+		}
+		selects += s + ",\n"
+	}
+
+	if len(selects) == 0 {
+		// No conditions (or all values are empty lists), so no need for a map.
+		return "", nil
+	}
+
+	// Create the map.
+	ret := " + select({\n"
+	ret += selects
+	// default condition comes last.
+	ret += fmt.Sprintf("%s\"%s\": %s,\n", makeIndent(indent+1), "//conditions:default", defaultValue)
+	ret += makeIndent(indent)
+	ret += "})"
+
+	return ret, nil
+}
+
+// prettyPrintSelectEntry converts a reflect.Value into an entry in a select map
+// with a provided key.
+func prettyPrintSelectEntry(value reflect.Value, key string, indent int) (string, error) {
+	s := makeIndent(indent + 1)
+	v, err := prettyPrint(value, indent+1)
+	if err != nil {
+		return "", err
+	}
+	s += fmt.Sprintf("\"%s\": %s", key, v)
+	return s, nil
+}
diff --git a/bp2build/conversion.go b/bp2build/conversion.go
index 787222d..6b47cd1 100644
--- a/bp2build/conversion.go
+++ b/bp2build/conversion.go
@@ -19,12 +19,13 @@
 	ruleShims map[string]RuleShim,
 	buildToTargets map[string]BazelTargets,
 	mode CodegenMode) []BazelFile {
-	files := make([]BazelFile, 0, len(ruleShims)+len(buildToTargets)+numAdditionalFiles)
 
-	// Write top level files: WORKSPACE. These files are empty.
-	files = append(files, newFile("", "WORKSPACE", ""))
+	var files []BazelFile
 
 	if mode == QueryView {
+		// Write top level WORKSPACE.
+		files = append(files, newFile("", "WORKSPACE", ""))
+
 		// Used to denote that the top level directory is a package.
 		files = append(files, newFile("", GeneratedBuildFileName, ""))
 
diff --git a/bp2build/conversion_test.go b/bp2build/conversion_test.go
index a115ddc..9fd6817 100644
--- a/bp2build/conversion_test.go
+++ b/bp2build/conversion_test.go
@@ -24,36 +24,6 @@
 	basename string
 }
 
-func assertFilecountsAreEqual(t *testing.T, actual []BazelFile, expected []filepath) {
-	if a, e := len(actual), len(expected); a != e {
-		t.Errorf("Expected %d files, got %d", e, a)
-	}
-}
-
-func assertFileContent(t *testing.T, actual []BazelFile, expected []filepath) {
-	for i := range actual {
-		if g, w := actual[i], expected[i]; g.Dir != w.dir || g.Basename != w.basename {
-			t.Errorf("Did not find expected file %s/%s", g.Dir, g.Basename)
-		} else if g.Basename == "BUILD" || g.Basename == "WORKSPACE" {
-			if g.Contents != "" {
-				t.Errorf("Expected %s to have no content.", g)
-			}
-		} else if g.Contents == "" {
-			t.Errorf("Contents of %s unexpected empty.", g)
-		}
-	}
-}
-
-func sortFiles(files []BazelFile) {
-	sort.Slice(files, func(i, j int) bool {
-		if dir1, dir2 := files[i].Dir, files[j].Dir; dir1 == dir2 {
-			return files[i].Basename < files[j].Basename
-		} else {
-			return dir1 < dir2
-		}
-	})
-}
-
 func TestCreateBazelFiles_QueryView_AddsTopLevelFiles(t *testing.T) {
 	files := CreateBazelFiles(map[string]RuleShim{}, map[string]BazelTargets{}, QueryView)
 	expectedFilePaths := []filepath{
@@ -79,21 +49,39 @@
 		},
 	}
 
-	assertFilecountsAreEqual(t, files, expectedFilePaths)
-	sortFiles(files)
-	assertFileContent(t, files, expectedFilePaths)
-}
-
-func TestCreateBazelFiles_Bp2Build_AddsTopLevelFiles(t *testing.T) {
-	files := CreateBazelFiles(map[string]RuleShim{}, map[string]BazelTargets{}, Bp2Build)
-	expectedFilePaths := []filepath{
-		{
-			dir:      "",
-			basename: "WORKSPACE",
-		},
+	// Compare number of files
+	if a, e := len(files), len(expectedFilePaths); a != e {
+		t.Errorf("Expected %d files, got %d", e, a)
 	}
 
-	assertFilecountsAreEqual(t, files, expectedFilePaths)
-	sortFiles(files)
-	assertFileContent(t, files, expectedFilePaths)
+	// Sort the files to be deterministic
+	sort.Slice(files, func(i, j int) bool {
+		if dir1, dir2 := files[i].Dir, files[j].Dir; dir1 == dir2 {
+			return files[i].Basename < files[j].Basename
+		} else {
+			return dir1 < dir2
+		}
+	})
+
+	// Compare the file contents
+	for i := range files {
+		actualFile, expectedFile := files[i], expectedFilePaths[i]
+
+		if actualFile.Dir != expectedFile.dir || actualFile.Basename != expectedFile.basename {
+			t.Errorf("Did not find expected file %s/%s", actualFile.Dir, actualFile.Basename)
+		} else if actualFile.Basename == "BUILD" || actualFile.Basename == "WORKSPACE" {
+			if actualFile.Contents != "" {
+				t.Errorf("Expected %s to have no content.", actualFile)
+			}
+		} else if actualFile.Contents == "" {
+			t.Errorf("Contents of %s unexpected empty.", actualFile)
+		}
+	}
+}
+
+func TestCreateBazelFiles_Bp2Build_CreatesNoFilesWithNoTargets(t *testing.T) {
+	files := CreateBazelFiles(map[string]RuleShim{}, map[string]BazelTargets{}, Bp2Build)
+	if len(files) != 0 {
+		t.Errorf("Expected no files, got %d", len(files))
+	}
 }
diff --git a/bp2build/testing.go b/bp2build/testing.go
index ede8044..ef3a78f 100644
--- a/bp2build/testing.go
+++ b/bp2build/testing.go
@@ -5,6 +5,13 @@
 	"android/soong/bazel"
 )
 
+var (
+	// A default configuration for tests to not have to specify bp2build_available on top level targets.
+	bp2buildConfig = android.Bp2BuildConfig{
+		android.BP2BUILD_TOPLEVEL: android.Bp2BuildDefaultTrueRecursively,
+	}
+)
+
 type nestedProps struct {
 	Nested_prop string
 }
diff --git a/cc/Android.bp b/cc/Android.bp
index 79e92cb..cc4d9bc 100644
--- a/cc/Android.bp
+++ b/cc/Android.bp
@@ -20,6 +20,7 @@
         "androidmk.go",
         "api_level.go",
         "builder.go",
+        "bp2build.go",
         "cc.go",
         "ccdeps.go",
         "check.go",
diff --git a/cc/bp2build.go b/cc/bp2build.go
new file mode 100644
index 0000000..2a590eb
--- /dev/null
+++ b/cc/bp2build.go
@@ -0,0 +1,106 @@
+// Copyright 2021 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package cc
+
+import (
+	"android/soong/android"
+	"android/soong/bazel"
+)
+
+// bp2build functions and helpers for converting cc_* modules to Bazel.
+
+func init() {
+	android.DepsBp2BuildMutators(RegisterDepsBp2Build)
+}
+
+func RegisterDepsBp2Build(ctx android.RegisterMutatorsContext) {
+	ctx.BottomUp("cc_bp2build_deps", depsBp2BuildMutator)
+}
+
+// A naive deps mutator to add deps on all modules across all combinations of
+// target props for cc modules. This is needed to make module -> bazel label
+// resolution work in the bp2build mutator later. This is probably
+// the wrong way to do it, but it works.
+//
+// TODO(jingwen): can we create a custom os mutator in depsBp2BuildMutator to do this?
+func depsBp2BuildMutator(ctx android.BottomUpMutatorContext) {
+	module, ok := ctx.Module().(*Module)
+	if !ok {
+		// Not a cc module
+		return
+	}
+
+	if !module.ConvertWithBp2build(ctx) {
+		return
+	}
+
+	var allDeps []string
+
+	for _, p := range module.GetTargetProperties(&BaseLinkerProperties{}) {
+		// arch specific linker props
+		if baseLinkerProps, ok := p.(*BaseLinkerProperties); ok {
+			allDeps = append(allDeps, baseLinkerProps.Header_libs...)
+			allDeps = append(allDeps, baseLinkerProps.Export_header_lib_headers...)
+		}
+	}
+
+	ctx.AddDependency(module, nil, android.SortedUniqueStrings(allDeps)...)
+}
+
+// bp2BuildParseHeaderLibs creates a label list attribute containing the header library deps of a module, including
+// configurable attribute values.
+func bp2BuildParseHeaderLibs(ctx android.TopDownMutatorContext, module *Module) bazel.LabelListAttribute {
+	var ret bazel.LabelListAttribute
+	for _, linkerProps := range module.linker.linkerProps() {
+		if baseLinkerProps, ok := linkerProps.(*BaseLinkerProperties); ok {
+			libs := baseLinkerProps.Header_libs
+			libs = append(libs, baseLinkerProps.Export_header_lib_headers...)
+			ret = bazel.MakeLabelListAttribute(
+				android.BazelLabelForModuleDeps(ctx, android.SortedUniqueStrings(libs)))
+			break
+		}
+	}
+
+	for os, p := range module.GetTargetProperties(&BaseLinkerProperties{}) {
+		if baseLinkerProps, ok := p.(*BaseLinkerProperties); ok {
+			libs := baseLinkerProps.Header_libs
+			libs = append(libs, baseLinkerProps.Export_header_lib_headers...)
+			libs = android.SortedUniqueStrings(libs)
+			ret.SetValueForOS(os.Name, android.BazelLabelForModuleDeps(ctx, libs))
+		}
+	}
+
+	return ret
+}
+
+// bp2BuildParseExportedIncludes creates a label list attribute contains the
+// exported included directories of a module.
+func bp2BuildParseExportedIncludes(ctx android.TopDownMutatorContext, module *Module) (bazel.LabelListAttribute, bazel.LabelListAttribute) {
+	libraryDecorator := module.linker.(*libraryDecorator)
+
+	includeDirs := libraryDecorator.flagExporter.Properties.Export_system_include_dirs
+	includeDirs = append(includeDirs, libraryDecorator.flagExporter.Properties.Export_include_dirs...)
+
+	includeDirsLabels := android.BazelLabelForModuleSrc(ctx, includeDirs)
+
+	var includeDirGlobs []string
+	for _, includeDir := range includeDirs {
+		includeDirGlobs = append(includeDirGlobs, includeDir+"/**/*.h")
+		includeDirGlobs = append(includeDirGlobs, includeDir+"/**/*.inc")
+		includeDirGlobs = append(includeDirGlobs, includeDir+"/**/*.hpp")
+	}
+
+	headersLabels := android.BazelLabelForModuleSrc(ctx, includeDirGlobs)
+	return bazel.MakeLabelListAttribute(includeDirsLabels), bazel.MakeLabelListAttribute(headersLabels)
+}
diff --git a/cc/builder.go b/cc/builder.go
index 4771b89..8c9743f 100644
--- a/cc/builder.go
+++ b/cc/builder.go
@@ -182,11 +182,11 @@
 		blueprint.RuleParams{
 			Depfile:     "${out}.d",
 			Deps:        blueprint.DepsGCC,
-			Command:     "CROSS_COMPILE=$crossCompile $tocPath $format -i ${in} -o ${out} -d ${out}.d",
+			Command:     "CLANG_BIN=$clangBin $tocPath $format -i ${in} -o ${out} -d ${out}.d",
 			CommandDeps: []string{"$tocPath"},
 			Restat:      true,
 		},
-		"crossCompile", "format")
+		"clangBin", "format")
 
 	// Rule for invoking clang-tidy (a clang-based linter).
 	clangTidy, clangTidyRE = pctx.RemoteStaticRules("clangTidy",
@@ -918,16 +918,12 @@
 	outputFile android.WritablePath, flags builderFlags) {
 
 	var format string
-	var crossCompile string
 	if ctx.Darwin() {
 		format = "--macho"
-		crossCompile = "${config.MacToolPath}"
 	} else if ctx.Windows() {
 		format = "--pe"
-		crossCompile = gccCmd(flags.toolchain, "")
 	} else {
 		format = "--elf"
-		crossCompile = gccCmd(flags.toolchain, "")
 	}
 
 	ctx.Build(pctx, android.BuildParams{
@@ -936,8 +932,8 @@
 		Output:      outputFile,
 		Input:       inputFile,
 		Args: map[string]string{
-			"crossCompile": crossCompile,
-			"format":       format,
+			"clangBin": "${config.ClangBin}",
+			"format":   format,
 		},
 	})
 }
diff --git a/cc/cc.go b/cc/cc.go
index 33dd177..0f9a556 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -1892,8 +1892,8 @@
 	}
 
 	for _, lib := range deps.ReexportStaticLibHeaders {
-		if !inList(lib, deps.StaticLibs) {
-			ctx.PropertyErrorf("export_static_lib_headers", "Static library not in static_libs: '%s'", lib)
+		if !inList(lib, deps.StaticLibs) && !inList(lib, deps.WholeStaticLibs) {
+			ctx.PropertyErrorf("export_static_lib_headers", "Static library not in static_libs or whole_static_libs: '%s'", lib)
 		}
 	}
 
diff --git a/cc/library.go b/cc/library.go
index 091acfe..50fff7f 100644
--- a/cc/library.go
+++ b/cc/library.go
@@ -2046,38 +2046,6 @@
 	return outputFile
 }
 
-func Bp2BuildParseHeaderLibs(ctx android.TopDownMutatorContext, module *Module) bazel.LabelListAttribute {
-	var headerLibs []string
-	for _, linkerProps := range module.linker.linkerProps() {
-		if baseLinkerProps, ok := linkerProps.(*BaseLinkerProperties); ok {
-			headerLibs = baseLinkerProps.Header_libs
-			// FIXME: re-export include dirs from baseLinkerProps.Export_header_lib_headers?
-			break
-		}
-	}
-	headerLibsLabels := bazel.MakeLabelListAttribute(android.BazelLabelForModuleDeps(ctx, headerLibs))
-	return headerLibsLabels
-}
-
-func Bp2BuildParseExportedIncludes(ctx android.TopDownMutatorContext, module *Module) (bazel.LabelListAttribute, bazel.LabelListAttribute) {
-	libraryDecorator := module.linker.(*libraryDecorator)
-
-	includeDirs := libraryDecorator.flagExporter.Properties.Export_system_include_dirs
-	includeDirs = append(includeDirs, libraryDecorator.flagExporter.Properties.Export_include_dirs...)
-
-	includeDirsLabels := android.BazelLabelForModuleSrc(ctx, includeDirs)
-
-	var includeDirGlobs []string
-	for _, includeDir := range includeDirs {
-		includeDirGlobs = append(includeDirGlobs, includeDir+"/**/*.h")
-		includeDirGlobs = append(includeDirGlobs, includeDir+"/**/*.inc")
-		includeDirGlobs = append(includeDirGlobs, includeDir+"/**/*.hpp")
-	}
-
-	headersLabels := android.BazelLabelForModuleSrc(ctx, includeDirGlobs)
-	return bazel.MakeLabelListAttribute(includeDirsLabels), bazel.MakeLabelListAttribute(headersLabels)
-}
-
 type bazelCcLibraryStaticAttributes struct {
 	Copts      []string
 	Srcs       bazel.LabelListAttribute
@@ -2149,10 +2117,10 @@
 	allIncludes = append(allIncludes, localIncludeDirs...)
 	includesLabels := android.BazelLabelForModuleSrc(ctx, allIncludes)
 
-	exportedIncludesLabels, exportedIncludesHeadersLabels := Bp2BuildParseExportedIncludes(ctx, module)
+	exportedIncludesLabels, exportedIncludesHeadersLabels := bp2BuildParseExportedIncludes(ctx, module)
 	includesLabels.Append(exportedIncludesLabels.Value)
 
-	headerLibsLabels := Bp2BuildParseHeaderLibs(ctx, module)
+	headerLibsLabels := bp2BuildParseHeaderLibs(ctx, module)
 	depsLabels.Append(headerLibsLabels.Value)
 
 	attrs := &bazelCcLibraryStaticAttributes{
diff --git a/cc/library_headers.go b/cc/library_headers.go
index 8286848..c8dd2c2 100644
--- a/cc/library_headers.go
+++ b/cc/library_headers.go
@@ -94,9 +94,9 @@
 		return
 	}
 
-	exportedIncludesLabels, exportedIncludesHeadersLabels := Bp2BuildParseExportedIncludes(ctx, module)
+	exportedIncludesLabels, exportedIncludesHeadersLabels := bp2BuildParseExportedIncludes(ctx, module)
 
-	headerLibsLabels := Bp2BuildParseHeaderLibs(ctx, module)
+	headerLibsLabels := bp2BuildParseHeaderLibs(ctx, module)
 
 	attrs := &bazelCcLibraryHeadersAttributes{
 		Includes: exportedIncludesLabels,
diff --git a/cc/stl.go b/cc/stl.go
index 75fab17..594231d 100644
--- a/cc/stl.go
+++ b/cc/stl.go
@@ -188,12 +188,7 @@
 		if needsLibAndroidSupport(ctx) {
 			deps.StaticLibs = append(deps.StaticLibs, "ndk_libandroid_support")
 		}
-		// TODO: Switch the NDK over to the LLVM unwinder for non-arm32 architectures.
-		if ctx.Arch().ArchType == android.Arm {
-			deps.StaticLibs = append(deps.StaticLibs, "ndk_libunwind")
-		} else {
-			deps.StaticLibs = append(deps.StaticLibs, "libgcc_stripped")
-		}
+		deps.StaticLibs = append(deps.StaticLibs, "ndk_libunwind")
 	default:
 		panic(fmt.Errorf("Unknown stl: %q", stl.Properties.SelectedStl))
 	}
diff --git a/filesystem/logical_partition.go b/filesystem/logical_partition.go
index dbbc1d8..739e609 100644
--- a/filesystem/logical_partition.go
+++ b/filesystem/logical_partition.go
@@ -40,7 +40,8 @@
 	// Set the name of the output. Defaults to <module_name>.img.
 	Stem *string
 
-	// Total size of the logical partition
+	// Total size of the logical partition. If set to "auto", total size is automatically
+	// calcaulted as minimum.
 	Size *string
 
 	// List of partitions for default group. Default group has no size limit and automatically
@@ -117,9 +118,8 @@
 	size := proptools.String(l.properties.Size)
 	if size == "" {
 		ctx.PropertyErrorf("size", "must be set")
-	}
-	if _, err := strconv.Atoi(size); err != nil {
-		ctx.PropertyErrorf("size", "must be a number")
+	} else if _, err := strconv.Atoi(size); err != nil && size != "auto" {
+		ctx.PropertyErrorf("size", `must be a number or "auto"`)
 	}
 	cmd.FlagWithArg("--device-size=", size)
 
diff --git a/java/aar.go b/java/aar.go
index 67b9ef0..a122a94 100644
--- a/java/aar.go
+++ b/java/aar.go
@@ -163,7 +163,7 @@
 		a.aaptProperties.RROEnforcedForDependent
 }
 
-func (a *aapt) aapt2Flags(ctx android.ModuleContext, sdkContext sdkContext,
+func (a *aapt) aapt2Flags(ctx android.ModuleContext, sdkContext android.SdkContext,
 	manifestPath android.Path) (compileFlags, linkFlags []string, linkDeps android.Paths,
 	resDirs, overlayDirs []globbedResourceDir, rroDirs []rroDir, resZips android.Paths) {
 
@@ -218,7 +218,7 @@
 	linkDeps = append(linkDeps, assetDeps...)
 
 	// SDK version flags
-	minSdkVersion, err := sdkContext.minSdkVersion().effectiveVersionString(ctx)
+	minSdkVersion, err := sdkContext.MinSdkVersion().EffectiveVersionString(ctx)
 	if err != nil {
 		ctx.ModuleErrorf("invalid minSdkVersion: %s", err)
 	}
@@ -266,7 +266,7 @@
 		CommandDeps: []string{"${config.Zip2ZipCmd}"},
 	})
 
-func (a *aapt) buildActions(ctx android.ModuleContext, sdkContext sdkContext,
+func (a *aapt) buildActions(ctx android.ModuleContext, sdkContext android.SdkContext,
 	classLoaderContexts dexpreopt.ClassLoaderContextMap, extraLinkFlags ...string) {
 
 	transitiveStaticLibs, transitiveStaticLibManifests, staticRRODirs, assetPackages, libDeps, libFlags :=
@@ -397,7 +397,7 @@
 }
 
 // aaptLibs collects libraries from dependencies and sdk_version and converts them into paths
-func aaptLibs(ctx android.ModuleContext, sdkContext sdkContext, classLoaderContexts dexpreopt.ClassLoaderContextMap) (
+func aaptLibs(ctx android.ModuleContext, sdkContext android.SdkContext, classLoaderContexts dexpreopt.ClassLoaderContextMap) (
 	transitiveStaticLibs, transitiveStaticLibManifests android.Paths, staticRRODirs []rroDir, assets, deps android.Paths, flags []string) {
 
 	var sharedLibs android.Paths
@@ -498,7 +498,7 @@
 
 func (a *AndroidLibrary) DepsMutator(ctx android.BottomUpMutatorContext) {
 	a.Module.deps(ctx)
-	sdkDep := decodeSdkDep(ctx, sdkContext(a))
+	sdkDep := decodeSdkDep(ctx, android.SdkContext(a))
 	if sdkDep.hasFrameworkLibs() {
 		a.aapt.deps(ctx, sdkDep)
 	}
@@ -507,7 +507,7 @@
 func (a *AndroidLibrary) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	a.aapt.isLibrary = true
 	a.classLoaderContexts = make(dexpreopt.ClassLoaderContextMap)
-	a.aapt.buildActions(ctx, sdkContext(a), a.classLoaderContexts)
+	a.aapt.buildActions(ctx, android.SdkContext(a), a.classLoaderContexts)
 
 	a.hideApexVariantFromMake = !ctx.Provider(android.ApexInfoProvider).(android.ApexInfo).IsForPlatform()
 
@@ -625,23 +625,23 @@
 	}
 }
 
-func (a *AARImport) sdkVersion() sdkSpec {
-	return sdkSpecFrom(String(a.properties.Sdk_version))
+func (a *AARImport) SdkVersion() android.SdkSpec {
+	return android.SdkSpecFrom(String(a.properties.Sdk_version))
 }
 
-func (a *AARImport) systemModules() string {
+func (a *AARImport) SystemModules() string {
 	return ""
 }
 
-func (a *AARImport) minSdkVersion() sdkSpec {
+func (a *AARImport) MinSdkVersion() android.SdkSpec {
 	if a.properties.Min_sdk_version != nil {
-		return sdkSpecFrom(*a.properties.Min_sdk_version)
+		return android.SdkSpecFrom(*a.properties.Min_sdk_version)
 	}
-	return a.sdkVersion()
+	return a.SdkVersion()
 }
 
-func (a *AARImport) targetSdkVersion() sdkSpec {
-	return a.sdkVersion()
+func (a *AARImport) TargetSdkVersion() android.SdkSpec {
+	return a.SdkVersion()
 }
 
 func (a *AARImport) javaVersion() string {
@@ -700,7 +700,7 @@
 
 func (a *AARImport) DepsMutator(ctx android.BottomUpMutatorContext) {
 	if !ctx.Config().AlwaysUsePrebuiltSdks() {
-		sdkDep := decodeSdkDep(ctx, sdkContext(a))
+		sdkDep := decodeSdkDep(ctx, android.SdkContext(a))
 		if sdkDep.useModule && sdkDep.frameworkResModule != "" {
 			ctx.AddVariationDependencies(nil, frameworkResTag, sdkDep.frameworkResModule)
 		}
@@ -780,7 +780,7 @@
 	linkDeps = append(linkDeps, a.manifest)
 
 	transitiveStaticLibs, staticLibManifests, staticRRODirs, transitiveAssets, libDeps, libFlags :=
-		aaptLibs(ctx, sdkContext(a), nil)
+		aaptLibs(ctx, android.SdkContext(a), nil)
 
 	_ = staticLibManifests
 	_ = staticRRODirs
diff --git a/java/android_manifest.go b/java/android_manifest.go
index b30f3d2..6b7395b 100644
--- a/java/android_manifest.go
+++ b/java/android_manifest.go
@@ -43,7 +43,7 @@
 	"args", "libs")
 
 // Uses manifest_fixer.py to inject minSdkVersion, etc. into an AndroidManifest.xml
-func manifestFixer(ctx android.ModuleContext, manifest android.Path, sdkContext sdkContext,
+func manifestFixer(ctx android.ModuleContext, manifest android.Path, sdkContext android.SdkContext,
 	classLoaderContexts dexpreopt.ClassLoaderContextMap, isLibrary, useEmbeddedNativeLibs, usesNonSdkApis,
 	useEmbeddedDex, hasNoCode bool, loggingParent string) android.Path {
 
@@ -51,7 +51,7 @@
 	if isLibrary {
 		args = append(args, "--library")
 	} else {
-		minSdkVersion, err := sdkContext.minSdkVersion().effectiveVersion(ctx)
+		minSdkVersion, err := sdkContext.MinSdkVersion().EffectiveVersion(ctx)
 		if err != nil {
 			ctx.ModuleErrorf("invalid minSdkVersion: %s", err)
 		}
@@ -87,7 +87,7 @@
 		args = append(args, "--logging-parent", loggingParent)
 	}
 	var deps android.Paths
-	targetSdkVersion, err := sdkContext.targetSdkVersion().effectiveVersionString(ctx)
+	targetSdkVersion, err := sdkContext.TargetSdkVersion().EffectiveVersionString(ctx)
 	if err != nil {
 		ctx.ModuleErrorf("invalid targetSdkVersion: %s", err)
 	}
@@ -96,7 +96,7 @@
 		deps = append(deps, ApiFingerprintPath(ctx))
 	}
 
-	minSdkVersion, err := sdkContext.minSdkVersion().effectiveVersionString(ctx)
+	minSdkVersion, err := sdkContext.MinSdkVersion().EffectiveVersionString(ctx)
 	if err != nil {
 		ctx.ModuleErrorf("invalid minSdkVersion: %s", err)
 	}
diff --git a/java/androidmk.go b/java/androidmk.go
index 3d3eae5..75661a7 100644
--- a/java/androidmk.go
+++ b/java/androidmk.go
@@ -106,7 +106,7 @@
 					if len(library.dexpreopter.builtInstalled) > 0 {
 						entries.SetString("LOCAL_SOONG_BUILT_INSTALLED", library.dexpreopter.builtInstalled)
 					}
-					entries.SetString("LOCAL_SDK_VERSION", library.sdkVersion().raw)
+					entries.SetString("LOCAL_SDK_VERSION", library.SdkVersion().Raw)
 					entries.SetPath("LOCAL_SOONG_CLASSES_JAR", library.implementationAndResourcesJar)
 					entries.SetPath("LOCAL_SOONG_HEADER_JAR", library.headerJarFile)
 
@@ -255,7 +255,7 @@
 				entries.SetPath("LOCAL_SOONG_EXPORT_PROGUARD_FLAGS", prebuilt.proguardFlags)
 				entries.SetPath("LOCAL_SOONG_STATIC_LIBRARY_EXTRA_PACKAGES", prebuilt.extraAaptPackagesFile)
 				entries.SetPath("LOCAL_FULL_MANIFEST_FILE", prebuilt.manifest)
-				entries.SetString("LOCAL_SDK_VERSION", prebuilt.sdkVersion().raw)
+				entries.SetString("LOCAL_SDK_VERSION", prebuilt.SdkVersion().Raw)
 			},
 		},
 	}}
diff --git a/java/app.go b/java/app.go
index b849b98..ec30b49 100755
--- a/java/app.go
+++ b/java/app.go
@@ -213,16 +213,16 @@
 func (a *AndroidApp) DepsMutator(ctx android.BottomUpMutatorContext) {
 	a.Module.deps(ctx)
 
-	if String(a.appProperties.Stl) == "c++_shared" && !a.sdkVersion().specified() {
+	if String(a.appProperties.Stl) == "c++_shared" && !a.SdkVersion().Specified() {
 		ctx.PropertyErrorf("stl", "sdk_version must be set in order to use c++_shared")
 	}
 
-	sdkDep := decodeSdkDep(ctx, sdkContext(a))
+	sdkDep := decodeSdkDep(ctx, android.SdkContext(a))
 	if sdkDep.hasFrameworkLibs() {
 		a.aapt.deps(ctx, sdkDep)
 	}
 
-	usesSDK := a.sdkVersion().specified() && a.sdkVersion().kind != sdkCorePlatform
+	usesSDK := a.SdkVersion().Specified() && a.SdkVersion().Kind != android.SdkCorePlatform
 
 	if usesSDK && Bool(a.appProperties.Jni_uses_sdk_apis) {
 		ctx.PropertyErrorf("jni_uses_sdk_apis",
@@ -279,14 +279,14 @@
 
 func (a *AndroidApp) checkAppSdkVersions(ctx android.ModuleContext) {
 	if a.Updatable() {
-		if !a.sdkVersion().stable() {
-			ctx.PropertyErrorf("sdk_version", "Updatable apps must use stable SDKs, found %v", a.sdkVersion())
+		if !a.SdkVersion().Stable() {
+			ctx.PropertyErrorf("sdk_version", "Updatable apps must use stable SDKs, found %v", a.SdkVersion())
 		}
 		if String(a.deviceProperties.Min_sdk_version) == "" {
 			ctx.PropertyErrorf("updatable", "updatable apps must set min_sdk_version.")
 		}
 
-		if minSdkVersion, err := a.minSdkVersion().effectiveVersion(ctx); err == nil {
+		if minSdkVersion, err := a.MinSdkVersion().EffectiveVersion(ctx); err == nil {
 			a.checkJniLibsSdkVersion(ctx, minSdkVersion)
 			android.CheckMinSdkVersion(a, ctx, minSdkVersion.ApiLevel(ctx))
 		} else {
@@ -304,7 +304,7 @@
 // because, sdk_version is overridden by min_sdk_version (if set as smaller)
 // and sdkLinkType is checked with dependencies so we can be sure that the whole dependency tree
 // will meet the requirements.
-func (a *AndroidApp) checkJniLibsSdkVersion(ctx android.ModuleContext, minSdkVersion sdkVersion) {
+func (a *AndroidApp) checkJniLibsSdkVersion(ctx android.ModuleContext, minSdkVersion android.SdkVersion) {
 	// It's enough to check direct JNI deps' sdk_version because all transitive deps from JNI deps are checked in cc.checkLinkType()
 	ctx.VisitDirectDeps(func(m android.Module) {
 		if !IsJniDepTag(ctx.OtherModuleDependencyTag(m)) {
@@ -312,9 +312,9 @@
 		}
 		dep, _ := m.(*cc.Module)
 		// The domain of cc.sdk_version is "current" and <number>
-		// We can rely on sdkSpec to convert it to <number> so that "current" is handled
-		// properly regardless of sdk finalization.
-		jniSdkVersion, err := sdkSpecFrom(dep.SdkVersion()).effectiveVersion(ctx)
+		// We can rely on android.SdkSpec to convert it to <number> so that "current" is
+		// handled properly regardless of sdk finalization.
+		jniSdkVersion, err := android.SdkSpecFrom(dep.SdkVersion()).EffectiveVersion(ctx)
 		if err != nil || minSdkVersion < jniSdkVersion {
 			ctx.OtherModuleErrorf(dep, "sdk_version(%v) is higher than min_sdk_version(%v) of the containing android_app(%v)",
 				dep.SdkVersion(), minSdkVersion, ctx.ModuleName())
@@ -327,9 +327,9 @@
 // Returns true if the native libraries should be stored in the APK uncompressed and the
 // extractNativeLibs application flag should be set to false in the manifest.
 func (a *AndroidApp) useEmbeddedNativeLibs(ctx android.ModuleContext) bool {
-	minSdkVersion, err := a.minSdkVersion().effectiveVersion(ctx)
+	minSdkVersion, err := a.MinSdkVersion().EffectiveVersion(ctx)
 	if err != nil {
-		ctx.PropertyErrorf("min_sdk_version", "invalid value %q: %s", a.minSdkVersion(), err)
+		ctx.PropertyErrorf("min_sdk_version", "invalid value %q: %s", a.MinSdkVersion(), err)
 	}
 
 	apexInfo := ctx.Provider(android.ApexInfoProvider).(android.ApexInfo)
@@ -419,7 +419,7 @@
 
 	a.aapt.splitNames = a.appProperties.Package_splits
 	a.aapt.LoggingParent = String(a.overridableAppProperties.Logging_parent)
-	a.aapt.buildActions(ctx, sdkContext(a), a.classLoaderContexts, aaptLinkFlags...)
+	a.aapt.buildActions(ctx, android.SdkContext(a), a.classLoaderContexts, aaptLinkFlags...)
 
 	// apps manifests are handled by aapt, don't let Module see them
 	a.properties.Manifest = nil
@@ -720,8 +720,8 @@
 }
 
 type appDepsInterface interface {
-	sdkVersion() sdkSpec
-	minSdkVersion() sdkSpec
+	SdkVersion() android.SdkSpec
+	MinSdkVersion() android.SdkSpec
 	RequiresStableAPIs(ctx android.BaseModuleContext) bool
 }
 
@@ -734,8 +734,8 @@
 	seenModulePaths := make(map[string]bool)
 
 	if checkNativeSdkVersion {
-		checkNativeSdkVersion = app.sdkVersion().specified() &&
-			app.sdkVersion().kind != sdkCorePlatform && !app.RequiresStableAPIs(ctx)
+		checkNativeSdkVersion = app.SdkVersion().Specified() &&
+			app.SdkVersion().Kind != android.SdkCorePlatform && !app.RequiresStableAPIs(ctx)
 	}
 
 	ctx.WalkDeps(func(module android.Module, parent android.Module) bool {
@@ -829,6 +829,10 @@
 				if v := m.MinSdkVersion(); v != "" {
 					toMinSdkVersion = v
 				}
+			} else if m, ok := to.(interface{ MinSdkVersionString() string }); ok {
+				if v := m.MinSdkVersionString(); v != "" {
+					toMinSdkVersion = v
+				}
 			}
 			depsInfo[depName] = android.ApexModuleDepInfo{
 				To:            depName,
@@ -840,7 +844,7 @@
 		return true
 	})
 
-	a.ApexBundleDepsInfo.BuildDepsInfoLists(ctx, a.MinSdkVersion(), depsInfo)
+	a.ApexBundleDepsInfo.BuildDepsInfoLists(ctx, a.MinSdkVersionString(), depsInfo)
 }
 
 func (a *AndroidApp) Updatable() bool {
diff --git a/java/app_import.go b/java/app_import.go
index d4da64d..32cec23 100644
--- a/java/app_import.go
+++ b/java/app_import.go
@@ -394,12 +394,12 @@
 	return false
 }
 
-func (a *AndroidAppImport) sdkVersion() sdkSpec {
-	return sdkSpecFrom("")
+func (a *AndroidAppImport) SdkVersion() android.SdkSpec {
+	return android.SdkSpecFrom("")
 }
 
-func (a *AndroidAppImport) minSdkVersion() sdkSpec {
-	return sdkSpecFrom("")
+func (a *AndroidAppImport) MinSdkVersion() android.SdkSpec {
+	return android.SdkSpecFrom("")
 }
 
 var _ android.ApexModule = (*AndroidAppImport)(nil)
diff --git a/java/base.go b/java/base.go
index bd394af..73e5352 100644
--- a/java/base.go
+++ b/java/base.go
@@ -373,11 +373,11 @@
 }
 
 func (j *Module) CheckStableSdkVersion() error {
-	sdkVersion := j.sdkVersion()
-	if sdkVersion.stable() {
+	sdkVersion := j.SdkVersion()
+	if sdkVersion.Stable() {
 		return nil
 	}
-	if sdkVersion.kind == sdkCorePlatform {
+	if sdkVersion.Kind == android.SdkCorePlatform {
 		if useLegacyCorePlatformApiByName(j.BaseModuleName()) {
 			return fmt.Errorf("non stable SDK %v - uses legacy core platform", sdkVersion)
 		} else {
@@ -392,8 +392,8 @@
 // checkSdkVersions enforces restrictions around SDK dependencies.
 func (j *Module) checkSdkVersions(ctx android.ModuleContext) {
 	if j.RequiresStableAPIs(ctx) {
-		if sc, ok := ctx.Module().(sdkContext); ok {
-			if !sc.sdkVersion().specified() {
+		if sc, ok := ctx.Module().(android.SdkContext); ok {
+			if !sc.SdkVersion().Specified() {
 				ctx.PropertyErrorf("sdk_version",
 					"sdk_version must have a value when the module is located at vendor or product(only if PRODUCT_ENFORCE_PRODUCT_PARTITION_INTERFACE is set).")
 			}
@@ -416,9 +416,9 @@
 }
 
 func (j *Module) checkPlatformAPI(ctx android.ModuleContext) {
-	if sc, ok := ctx.Module().(sdkContext); ok {
+	if sc, ok := ctx.Module().(android.SdkContext); ok {
 		usePlatformAPI := proptools.Bool(j.deviceProperties.Platform_apis)
-		sdkVersionSpecified := sc.sdkVersion().specified()
+		sdkVersionSpecified := sc.SdkVersion().Specified()
 		if usePlatformAPI && sdkVersionSpecified {
 			ctx.PropertyErrorf("platform_apis", "platform_apis must be false when sdk_version is not empty.")
 		} else if !usePlatformAPI && !sdkVersionSpecified {
@@ -512,30 +512,30 @@
 	return false
 }
 
-func (j *Module) sdkVersion() sdkSpec {
-	return sdkSpecFrom(String(j.deviceProperties.Sdk_version))
+func (j *Module) SdkVersion() android.SdkSpec {
+	return android.SdkSpecFrom(String(j.deviceProperties.Sdk_version))
 }
 
-func (j *Module) systemModules() string {
+func (j *Module) SystemModules() string {
 	return proptools.String(j.deviceProperties.System_modules)
 }
 
-func (j *Module) minSdkVersion() sdkSpec {
+func (j *Module) MinSdkVersion() android.SdkSpec {
 	if j.deviceProperties.Min_sdk_version != nil {
-		return sdkSpecFrom(*j.deviceProperties.Min_sdk_version)
+		return android.SdkSpecFrom(*j.deviceProperties.Min_sdk_version)
 	}
-	return j.sdkVersion()
+	return j.SdkVersion()
 }
 
-func (j *Module) targetSdkVersion() sdkSpec {
+func (j *Module) TargetSdkVersion() android.SdkSpec {
 	if j.deviceProperties.Target_sdk_version != nil {
-		return sdkSpecFrom(*j.deviceProperties.Target_sdk_version)
+		return android.SdkSpecFrom(*j.deviceProperties.Target_sdk_version)
 	}
-	return j.sdkVersion()
+	return j.SdkVersion()
 }
 
-func (j *Module) MinSdkVersion() string {
-	return j.minSdkVersion().version.String()
+func (j *Module) MinSdkVersionString() string {
+	return j.MinSdkVersion().Version.String()
 }
 
 func (j *Module) AvailableFor(what string) bool {
@@ -552,7 +552,7 @@
 	if ctx.Device() {
 		j.linter.deps(ctx)
 
-		sdkDeps(ctx, sdkContext(j), j.dexer)
+		sdkDeps(ctx, android.SdkContext(j), j.dexer)
 
 		if j.deviceProperties.SyspropPublicStub != "" {
 			// This is a sysprop implementation library that has a corresponding sysprop public
@@ -702,7 +702,7 @@
 	var flags javaBuilderFlags
 
 	// javaVersion flag.
-	flags.javaVersion = getJavaVersion(ctx, String(j.properties.Java_version), sdkContext(j))
+	flags.javaVersion = getJavaVersion(ctx, String(j.properties.Java_version), android.SdkContext(j))
 
 	if ctx.Config().RunErrorProne() {
 		if config.ErrorProneClasspath == nil && ctx.Config().TestProductVariables == nil {
@@ -731,7 +731,7 @@
 	flags.processors = android.FirstUniqueStrings(flags.processors)
 
 	if len(flags.bootClasspath) == 0 && ctx.Host() && !flags.javaVersion.usesJavaModules() &&
-		decodeSdkDep(ctx, sdkContext(j)).hasStandardLibs() {
+		decodeSdkDep(ctx, android.SdkContext(j)).hasStandardLibs() {
 		// Give host-side tools a version of OpenJDK's standard libraries
 		// close to what they're targeting. As of Dec 2017, AOSP is only
 		// bundling OpenJDK 8 and 9, so nothing < 8 is available.
@@ -1209,7 +1209,7 @@
 			}
 			// Dex compilation
 			var dexOutputFile android.OutputPath
-			dexOutputFile = j.dexer.compileDex(ctx, flags, j.minSdkVersion(), outputFile, jarName)
+			dexOutputFile = j.dexer.compileDex(ctx, flags, j.MinSdkVersion(), outputFile, jarName)
 			if ctx.Failed() {
 				return
 			}
@@ -1254,8 +1254,8 @@
 	}
 
 	if ctx.Device() {
-		lintSDKVersionString := func(sdkSpec sdkSpec) string {
-			if v := sdkSpec.version; v.isNumbered() {
+		lintSDKVersionString := func(sdkSpec android.SdkSpec) string {
+			if v := sdkSpec.Version; v.IsNumbered() {
 				return v.String()
 			} else {
 				return ctx.Config().DefaultAppTargetSdk(ctx).String()
@@ -1267,9 +1267,9 @@
 		j.linter.srcJars = srcJars
 		j.linter.classpath = append(append(android.Paths(nil), flags.bootClasspath...), flags.classpath...)
 		j.linter.classes = j.implementationJarFile
-		j.linter.minSdkVersion = lintSDKVersionString(j.minSdkVersion())
-		j.linter.targetSdkVersion = lintSDKVersionString(j.targetSdkVersion())
-		j.linter.compileSdkVersion = lintSDKVersionString(j.sdkVersion())
+		j.linter.minSdkVersion = lintSDKVersionString(j.MinSdkVersion())
+		j.linter.targetSdkVersion = lintSDKVersionString(j.TargetSdkVersion())
+		j.linter.compileSdkVersion = lintSDKVersionString(j.SdkVersion())
 		j.linter.javaLanguageLevel = flags.javaVersion.String()
 		j.linter.kotlinLanguageLevel = "1.3"
 		if !apexInfo.IsForPlatform() && ctx.Config().UnbundledBuildApps() {
@@ -1471,14 +1471,14 @@
 // Implements android.ApexModule
 func (j *Module) ShouldSupportSdkVersion(ctx android.BaseModuleContext,
 	sdkVersion android.ApiLevel) error {
-	sdkSpec := j.minSdkVersion()
-	if !sdkSpec.specified() {
+	sdkSpec := j.MinSdkVersion()
+	if !sdkSpec.Specified() {
 		return fmt.Errorf("min_sdk_version is not specified")
 	}
-	if sdkSpec.kind == sdkCore {
+	if sdkSpec.Kind == android.SdkCore {
 		return nil
 	}
-	ver, err := sdkSpec.effectiveVersion(ctx)
+	ver, err := sdkSpec.EffectiveVersion(ctx)
 	if err != nil {
 		return err
 	}
@@ -1576,24 +1576,24 @@
 		return linkType, true
 	}
 
-	ver := m.sdkVersion()
-	switch ver.kind {
-	case sdkCore:
+	ver := m.SdkVersion()
+	switch ver.Kind {
+	case android.SdkCore:
 		return javaCore, false
-	case sdkSystem:
+	case android.SdkSystem:
 		return javaSystem, false
-	case sdkPublic:
+	case android.SdkPublic:
 		return javaSdk, false
-	case sdkModule:
+	case android.SdkModule:
 		return javaModule, false
-	case sdkSystemServer:
+	case android.SdkSystemServer:
 		return javaSystemServer, false
-	case sdkPrivate, sdkNone, sdkCorePlatform, sdkTest:
+	case android.SdkPrivate, android.SdkNone, android.SdkCorePlatform, android.SdkTest:
 		return javaPlatform, false
 	}
 
-	if !ver.valid() {
-		panic(fmt.Errorf("sdk_version is invalid. got %q", ver.raw))
+	if !ver.Valid() {
+		panic(fmt.Errorf("sdk_version is invalid. got %q", ver.Raw))
 	}
 	return javaSdk, false
 }
@@ -1625,7 +1625,7 @@
 	var deps deps
 
 	if ctx.Device() {
-		sdkDep := decodeSdkDep(ctx, sdkContext(j))
+		sdkDep := decodeSdkDep(ctx, android.SdkContext(j))
 		if sdkDep.invalidVersion {
 			ctx.AddMissingDependencies(sdkDep.bootclasspath)
 			ctx.AddMissingDependencies(sdkDep.java9Classpath)
@@ -1656,7 +1656,7 @@
 		if dep, ok := module.(SdkLibraryDependency); ok {
 			switch tag {
 			case libTag:
-				deps.classpath = append(deps.classpath, dep.SdkHeaderJars(ctx, j.sdkVersion())...)
+				deps.classpath = append(deps.classpath, dep.SdkHeaderJars(ctx, j.SdkVersion())...)
 			case staticLibTag:
 				ctx.ModuleErrorf("dependency on java_sdk_library %q can only be in libs", otherName)
 			}
diff --git a/java/config/kotlin.go b/java/config/kotlin.go
index fd8e3db..6cb61f3 100644
--- a/java/config/kotlin.go
+++ b/java/config/kotlin.go
@@ -35,11 +35,16 @@
 	pctx.SourcePathVariable("KotlinAnnotationJar", "external/kotlinc/lib/annotations-13.0.jar")
 	pctx.SourcePathVariable("KotlinStdlibJar", KotlinStdlibJar)
 
-	// These flags silence "Illegal reflective access" warnings when running kotlinc in OpenJDK9
-	pctx.StaticVariable("KotlincSuppressJDK9Warnings", strings.Join([]string{
+	// These flags silence "Illegal reflective access" warnings when running kapt in OpenJDK9+
+	pctx.StaticVariable("KaptSuppressJDK9Warnings", strings.Join([]string{
 		"-J--add-exports=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED",
 		"-J--add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED",
 		"-J--add-exports=jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED",
 		"-J--add-opens=java.base/sun.net.www.protocol.jar=ALL-UNNAMED",
 	}, " "))
+
+	// These flags silence "Illegal reflective access" warnings when running kotlinc in OpenJDK9+
+	pctx.StaticVariable("KotlincSuppressJDK9Warnings", strings.Join([]string{
+		"-J--add-opens=java.base/java.util=ALL-UNNAMED", // https://youtrack.jetbrains.com/issue/KT-43704
+	}, " "))
 }
diff --git a/java/dex.go b/java/dex.go
index b042f13..5c6d41d 100644
--- a/java/dex.go
+++ b/java/dex.go
@@ -157,7 +157,7 @@
 	}, []string{"outDir", "outDict", "outUsage", "outUsageZip", "outUsageDir",
 		"r8Flags", "zipFlags"}, []string{"implicits"})
 
-func (d *dexer) dexCommonFlags(ctx android.ModuleContext, minSdkVersion sdkSpec) []string {
+func (d *dexer) dexCommonFlags(ctx android.ModuleContext, minSdkVersion android.SdkSpec) []string {
 	flags := d.dexProperties.Dxflags
 	// Translate all the DX flags to D8 ones until all the build files have been migrated
 	// to D8 flags. See: b/69377755
@@ -174,12 +174,12 @@
 			"--verbose")
 	}
 
-	effectiveVersion, err := minSdkVersion.effectiveVersion(ctx)
+	effectiveVersion, err := minSdkVersion.EffectiveVersion(ctx)
 	if err != nil {
 		ctx.PropertyErrorf("min_sdk_version", "%s", err)
 	}
 
-	flags = append(flags, "--min-api "+effectiveVersion.asNumberString())
+	flags = append(flags, "--min-api "+effectiveVersion.AsNumberString())
 	return flags
 }
 
@@ -266,7 +266,7 @@
 	return r8Flags, r8Deps
 }
 
-func (d *dexer) compileDex(ctx android.ModuleContext, flags javaBuilderFlags, minSdkVersion sdkSpec,
+func (d *dexer) compileDex(ctx android.ModuleContext, flags javaBuilderFlags, minSdkVersion android.SdkSpec,
 	classesJar android.Path, jarName string) android.OutputPath {
 
 	// Compile classes.jar into classes.dex and then javalib.jar
diff --git a/java/droiddoc.go b/java/droiddoc.go
index f7595b1..a0d99a7 100644
--- a/java/droiddoc.go
+++ b/java/droiddoc.go
@@ -265,25 +265,25 @@
 
 var _ android.OutputFileProducer = (*Javadoc)(nil)
 
-func (j *Javadoc) sdkVersion() sdkSpec {
-	return sdkSpecFrom(String(j.properties.Sdk_version))
+func (j *Javadoc) SdkVersion() android.SdkSpec {
+	return android.SdkSpecFrom(String(j.properties.Sdk_version))
 }
 
-func (j *Javadoc) systemModules() string {
+func (j *Javadoc) SystemModules() string {
 	return proptools.String(j.properties.System_modules)
 }
 
-func (j *Javadoc) minSdkVersion() sdkSpec {
-	return j.sdkVersion()
+func (j *Javadoc) MinSdkVersion() android.SdkSpec {
+	return j.SdkVersion()
 }
 
-func (j *Javadoc) targetSdkVersion() sdkSpec {
-	return j.sdkVersion()
+func (j *Javadoc) TargetSdkVersion() android.SdkSpec {
+	return j.SdkVersion()
 }
 
 func (j *Javadoc) addDeps(ctx android.BottomUpMutatorContext) {
 	if ctx.Device() {
-		sdkDep := decodeSdkDep(ctx, sdkContext(j))
+		sdkDep := decodeSdkDep(ctx, android.SdkContext(j))
 		if sdkDep.useModule {
 			ctx.AddVariationDependencies(nil, bootClasspathTag, sdkDep.bootclasspath...)
 			ctx.AddVariationDependencies(nil, systemModulesTag, sdkDep.systemModules)
@@ -361,7 +361,7 @@
 func (j *Javadoc) collectDeps(ctx android.ModuleContext) deps {
 	var deps deps
 
-	sdkDep := decodeSdkDep(ctx, sdkContext(j))
+	sdkDep := decodeSdkDep(ctx, android.SdkContext(j))
 	if sdkDep.invalidVersion {
 		ctx.AddMissingDependencies(sdkDep.bootclasspath)
 		ctx.AddMissingDependencies(sdkDep.java9Classpath)
@@ -390,7 +390,7 @@
 			}
 		case libTag:
 			if dep, ok := module.(SdkLibraryDependency); ok {
-				deps.classpath = append(deps.classpath, dep.SdkHeaderJars(ctx, j.sdkVersion())...)
+				deps.classpath = append(deps.classpath, dep.SdkHeaderJars(ctx, j.SdkVersion())...)
 			} else if ctx.OtherModuleHasProvider(module, JavaInfoProvider) {
 				dep := ctx.OtherModuleProvider(module, JavaInfoProvider).(JavaInfo)
 				deps.classpath = append(deps.classpath, dep.HeaderJars...)
@@ -555,7 +555,7 @@
 
 	srcJarList := zipSyncCmd(ctx, rule, srcJarDir, j.srcJars)
 
-	javaVersion := getJavaVersion(ctx, String(j.properties.Java_version), sdkContext(j))
+	javaVersion := getJavaVersion(ctx, String(j.properties.Java_version), android.SdkContext(j))
 
 	cmd := javadocSystemModulesCmd(ctx, rule, j.srcFiles, outDir, srcJarDir, srcJarList,
 		deps.systemModules, deps.classpath, j.sourcepaths)
diff --git a/java/droidstubs.go b/java/droidstubs.go
index d7a0668..3469616 100644
--- a/java/droidstubs.go
+++ b/java/droidstubs.go
@@ -474,7 +474,7 @@
 func (d *Droidstubs) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	deps := d.Javadoc.collectDeps(ctx)
 
-	javaVersion := getJavaVersion(ctx, String(d.Javadoc.properties.Java_version), sdkContext(d))
+	javaVersion := getJavaVersion(ctx, String(d.Javadoc.properties.Java_version), android.SdkContext(d))
 
 	// Create rule for metalava
 
diff --git a/java/java.go b/java/java.go
index 26e5091..5fe8814 100644
--- a/java/java.go
+++ b/java/java.go
@@ -304,7 +304,7 @@
 	unstrippedFile android.Path
 }
 
-func sdkDeps(ctx android.BottomUpMutatorContext, sdkContext sdkContext, d dexer) {
+func sdkDeps(ctx android.BottomUpMutatorContext, sdkContext android.SdkContext, d dexer) {
 	sdkDep := decodeSdkDep(ctx, sdkContext)
 	if sdkDep.useModule {
 		ctx.AddVariationDependencies(nil, bootClasspathTag, sdkDep.bootclasspath...)
@@ -352,11 +352,11 @@
 	}
 }
 
-func getJavaVersion(ctx android.ModuleContext, javaVersion string, sdkContext sdkContext) javaVersion {
+func getJavaVersion(ctx android.ModuleContext, javaVersion string, sdkContext android.SdkContext) javaVersion {
 	if javaVersion != "" {
 		return normalizeJavaVersion(ctx, javaVersion)
 	} else if ctx.Device() {
-		return sdkContext.sdkVersion().defaultJavaLanguageVersion(ctx)
+		return defaultJavaLanguageVersion(ctx, sdkContext.SdkVersion())
 	} else {
 		return JAVA_VERSION_9
 	}
@@ -776,7 +776,7 @@
 func (j *Test) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	if j.testProperties.Test_options.Unit_test == nil && ctx.Host() {
 		// TODO(b/): Clean temporary heuristic to avoid unexpected onboarding.
-		defaultUnitTest := !inList("tradefed", j.properties.Static_libs) && !inList("tradefed", j.properties.Libs) && !inList("cts", j.testProperties.Test_suites)
+		defaultUnitTest := !inList("tradefed", j.properties.Libs) && !inList("cts", j.testProperties.Test_suites)
 		j.testProperties.Test_options.Unit_test = proptools.BoolPtr(defaultUnitTest)
 	}
 	j.testConfig = tradefed.AutoGenJavaTestConfig(ctx, j.testProperties.Test_config, j.testProperties.Test_config_template,
@@ -1132,31 +1132,31 @@
 	hideApexVariantFromMake bool
 }
 
-func (j *Import) sdkVersion() sdkSpec {
-	return sdkSpecFrom(String(j.properties.Sdk_version))
+func (j *Import) SdkVersion() android.SdkSpec {
+	return android.SdkSpecFrom(String(j.properties.Sdk_version))
 }
 
 func (j *Import) makeSdkVersion() string {
-	return j.sdkVersion().raw
+	return j.SdkVersion().Raw
 }
 
-func (j *Import) systemModules() string {
+func (j *Import) SystemModules() string {
 	return "none"
 }
 
-func (j *Import) minSdkVersion() sdkSpec {
+func (j *Import) MinSdkVersion() android.SdkSpec {
 	if j.properties.Min_sdk_version != nil {
-		return sdkSpecFrom(*j.properties.Min_sdk_version)
+		return android.SdkSpecFrom(*j.properties.Min_sdk_version)
 	}
-	return j.sdkVersion()
+	return j.SdkVersion()
 }
 
-func (j *Import) targetSdkVersion() sdkSpec {
-	return j.sdkVersion()
+func (j *Import) TargetSdkVersion() android.SdkSpec {
+	return j.SdkVersion()
 }
 
-func (j *Import) MinSdkVersion() string {
-	return j.minSdkVersion().version.String()
+func (j *Import) MinSdkVersionString() string {
+	return j.MinSdkVersion().Version.String()
 }
 
 func (j *Import) Prebuilt() *android.Prebuilt {
@@ -1187,7 +1187,7 @@
 	ctx.AddVariationDependencies(nil, libTag, j.properties.Libs...)
 
 	if ctx.Device() && Bool(j.dexProperties.Compile_dex) {
-		sdkDeps(ctx, sdkContext(j), j.dexer)
+		sdkDeps(ctx, android.SdkContext(j), j.dexer)
 	}
 }
 
@@ -1230,7 +1230,7 @@
 		} else if dep, ok := module.(SdkLibraryDependency); ok {
 			switch tag {
 			case libTag:
-				flags.classpath = append(flags.classpath, dep.SdkHeaderJars(ctx, j.sdkVersion())...)
+				flags.classpath = append(flags.classpath, dep.SdkHeaderJars(ctx, j.SdkVersion())...)
 			}
 		}
 
@@ -1272,7 +1272,7 @@
 				ctx.ModuleErrorf("internal error: no dex implementation jar available from prebuilt_apex %q", deapexerModule.Name())
 			}
 		} else if Bool(j.dexProperties.Compile_dex) {
-			sdkDep := decodeSdkDep(ctx, sdkContext(j))
+			sdkDep := decodeSdkDep(ctx, android.SdkContext(j))
 			if sdkDep.invalidVersion {
 				ctx.AddMissingDependencies(sdkDep.bootclasspath)
 				ctx.AddMissingDependencies(sdkDep.java9Classpath)
@@ -1291,7 +1291,7 @@
 			j.dexpreopter.uncompressedDex = *j.dexProperties.Uncompress_dex
 
 			var dexOutputFile android.OutputPath
-			dexOutputFile = j.dexer.compileDex(ctx, flags, j.minSdkVersion(), outputFile, jarName)
+			dexOutputFile = j.dexer.compileDex(ctx, flags, j.MinSdkVersion(), outputFile, jarName)
 			if ctx.Failed() {
 				return
 			}
@@ -1359,14 +1359,14 @@
 // Implements android.ApexModule
 func (j *Import) ShouldSupportSdkVersion(ctx android.BaseModuleContext,
 	sdkVersion android.ApiLevel) error {
-	sdkSpec := j.minSdkVersion()
-	if !sdkSpec.specified() {
+	sdkSpec := j.MinSdkVersion()
+	if !sdkSpec.Specified() {
 		return fmt.Errorf("min_sdk_version is not specified")
 	}
-	if sdkSpec.kind == sdkCore {
+	if sdkSpec.Kind == android.SdkCore {
 		return nil
 	}
-	ver, err := sdkSpec.effectiveVersion(ctx)
+	ver, err := sdkSpec.EffectiveVersion(ctx)
 	if err != nil {
 		return err
 	}
diff --git a/java/kotlin.go b/java/kotlin.go
index 2960f81..3a6fc0f 100644
--- a/java/kotlin.go
+++ b/java/kotlin.go
@@ -34,8 +34,9 @@
 			`${config.GenKotlinBuildFileCmd} --classpath "$classpath" --name "$name"` +
 			` --out_dir "$classesDir" --srcs "$out.rsp" --srcs "$srcJarDir/list"` +
 			` $commonSrcFilesArg --out "$kotlinBuildFile" && ` +
-			`${config.KotlincCmd} ${config.JavacHeapFlags} $kotlincFlags ` +
-			`-jvm-target $kotlinJvmTarget -Xbuild-file=$kotlinBuildFile -kotlin-home $emptyDir && ` +
+			`${config.KotlincCmd} ${config.KotlincSuppressJDK9Warnings} ${config.JavacHeapFlags} ` +
+			`$kotlincFlags -jvm-target $kotlinJvmTarget -Xbuild-file=$kotlinBuildFile ` +
+			`-kotlin-home $emptyDir && ` +
 			`${config.SoongZipCmd} -jar -o $out -C $classesDir -D $classesDir && ` +
 			`rm -rf "$srcJarDir"`,
 		CommandDeps: []string{
@@ -123,8 +124,8 @@
 			`${config.GenKotlinBuildFileCmd} --classpath "$classpath" --name "$name"` +
 			` --srcs "$out.rsp" --srcs "$srcJarDir/list"` +
 			` $commonSrcFilesArg --out "$kotlinBuildFile" && ` +
-			`${config.KotlincCmd} ${config.KotlincSuppressJDK9Warnings} ${config.JavacHeapFlags} $kotlincFlags ` +
-			`-Xplugin=${config.KotlinKaptJar} ` +
+			`${config.KotlincCmd} ${config.KaptSuppressJDK9Warnings} ${config.KotlincSuppressJDK9Warnings} ` +
+			`${config.JavacHeapFlags} $kotlincFlags -Xplugin=${config.KotlinKaptJar} ` +
 			`-P plugin:org.jetbrains.kotlin.kapt3:sources=$kaptDir/sources ` +
 			`-P plugin:org.jetbrains.kotlin.kapt3:classes=$kaptDir/classes ` +
 			`-P plugin:org.jetbrains.kotlin.kapt3:stubs=$kaptDir/stubs ` +
diff --git a/java/rro.go b/java/rro.go
index aafa88e..4ae0014 100644
--- a/java/rro.go
+++ b/java/rro.go
@@ -91,7 +91,7 @@
 }
 
 func (r *RuntimeResourceOverlay) DepsMutator(ctx android.BottomUpMutatorContext) {
-	sdkDep := decodeSdkDep(ctx, sdkContext(r))
+	sdkDep := decodeSdkDep(ctx, android.SdkContext(r))
 	if sdkDep.hasFrameworkLibs() {
 		r.aapt.deps(ctx, sdkDep)
 	}
@@ -141,23 +141,23 @@
 	ctx.InstallFile(r.installDir, r.outputFile.Base(), r.outputFile)
 }
 
-func (r *RuntimeResourceOverlay) sdkVersion() sdkSpec {
-	return sdkSpecFrom(String(r.properties.Sdk_version))
+func (r *RuntimeResourceOverlay) SdkVersion() android.SdkSpec {
+	return android.SdkSpecFrom(String(r.properties.Sdk_version))
 }
 
-func (r *RuntimeResourceOverlay) systemModules() string {
+func (r *RuntimeResourceOverlay) SystemModules() string {
 	return ""
 }
 
-func (r *RuntimeResourceOverlay) minSdkVersion() sdkSpec {
+func (r *RuntimeResourceOverlay) MinSdkVersion() android.SdkSpec {
 	if r.properties.Min_sdk_version != nil {
-		return sdkSpecFrom(*r.properties.Min_sdk_version)
+		return android.SdkSpecFrom(*r.properties.Min_sdk_version)
 	}
-	return r.sdkVersion()
+	return r.SdkVersion()
 }
 
-func (r *RuntimeResourceOverlay) targetSdkVersion() sdkSpec {
-	return r.sdkVersion()
+func (r *RuntimeResourceOverlay) TargetSdkVersion() android.SdkSpec {
+	return r.SdkVersion()
 }
 
 func (r *RuntimeResourceOverlay) Certificate() Certificate {
diff --git a/java/sdk.go b/java/sdk.go
index 74d5a81..b546ca0 100644
--- a/java/sdk.go
+++ b/java/sdk.go
@@ -19,7 +19,6 @@
 	"path/filepath"
 	"sort"
 	"strconv"
-	"strings"
 
 	"android/soong/android"
 	"android/soong/java/config"
@@ -38,19 +37,6 @@
 var nonUpdatableFrameworkAidlPathKey = android.NewOnceKey("nonUpdatableFrameworkAidlPathKey")
 var apiFingerprintPathKey = android.NewOnceKey("apiFingerprintPathKey")
 
-type sdkContext interface {
-	// sdkVersion returns sdkSpec that corresponds to the sdk_version property of the current module
-	sdkVersion() sdkSpec
-	// systemModules returns the system_modules property of the current module, or an empty string if it is not set.
-	systemModules() string
-	// minSdkVersion returns sdkSpec that corresponds to the min_sdk_version property of the current module,
-	// or from sdk_version if it is not set.
-	minSdkVersion() sdkSpec
-	// targetSdkVersion returns the sdkSpec that corresponds to the target_sdk_version property of the current module,
-	// or from sdk_version if it is not set.
-	targetSdkVersion() sdkSpec
-}
-
 func UseApiFingerprint(ctx android.BaseModuleContext) bool {
 	if ctx.Config().UnbundledBuild() &&
 		!ctx.Config().AlwaysUsePrebuiltSdks() &&
@@ -60,209 +46,8 @@
 	return false
 }
 
-// sdkKind represents a particular category of an SDK spec like public, system, test, etc.
-type sdkKind int
-
-const (
-	sdkInvalid sdkKind = iota
-	sdkNone
-	sdkCore
-	sdkCorePlatform
-	sdkPublic
-	sdkSystem
-	sdkTest
-	sdkModule
-	sdkSystemServer
-	sdkPrivate
-)
-
-// String returns the string representation of this sdkKind
-func (k sdkKind) String() string {
-	switch k {
-	case sdkPrivate:
-		return "private"
-	case sdkNone:
-		return "none"
-	case sdkPublic:
-		return "public"
-	case sdkSystem:
-		return "system"
-	case sdkTest:
-		return "test"
-	case sdkCore:
-		return "core"
-	case sdkCorePlatform:
-		return "core_platform"
-	case sdkModule:
-		return "module-lib"
-	case sdkSystemServer:
-		return "system-server"
-	default:
-		return "invalid"
-	}
-}
-
-// sdkVersion represents a specific version number of an SDK spec of a particular kind
-type sdkVersion int
-
-const (
-	// special version number for a not-yet-frozen SDK
-	sdkVersionCurrent sdkVersion = sdkVersion(android.FutureApiLevelInt)
-	// special version number to be used for SDK specs where version number doesn't
-	// make sense, e.g. "none", "", etc.
-	sdkVersionNone sdkVersion = sdkVersion(0)
-)
-
-// isCurrent checks if the sdkVersion refers to the not-yet-published version of an sdkKind
-func (v sdkVersion) isCurrent() bool {
-	return v == sdkVersionCurrent
-}
-
-// isNumbered checks if the sdkVersion refers to the published (a.k.a numbered) version of an sdkKind
-func (v sdkVersion) isNumbered() bool {
-	return !v.isCurrent() && v != sdkVersionNone
-}
-
-// String returns the string representation of this sdkVersion.
-func (v sdkVersion) String() string {
-	if v.isCurrent() {
-		return "current"
-	} else if v.isNumbered() {
-		return strconv.Itoa(int(v))
-	}
-	return "(no version)"
-}
-
-func (v sdkVersion) ApiLevel(ctx android.EarlyModuleContext) android.ApiLevel {
-	return android.ApiLevelOrPanic(ctx, v.String())
-}
-
-// asNumberString directly converts the numeric value of this sdk version as a string.
-// When isNumbered() is true, this method is the same as String(). However, for sdkVersionCurrent
-// and sdkVersionNone, this returns 10000 and 0 while String() returns "current" and "(no version"),
-// respectively.
-func (v sdkVersion) asNumberString() string {
-	return strconv.Itoa(int(v))
-}
-
-// sdkSpec represents the kind and the version of an SDK for a module to build against
-type sdkSpec struct {
-	kind    sdkKind
-	version sdkVersion
-	raw     string
-}
-
-func (s sdkSpec) String() string {
-	return fmt.Sprintf("%s_%s", s.kind, s.version)
-}
-
-// valid checks if this sdkSpec is well-formed. Note however that true doesn't mean that the
-// specified SDK actually exists.
-func (s sdkSpec) valid() bool {
-	return s.kind != sdkInvalid
-}
-
-// specified checks if this sdkSpec is well-formed and is not "".
-func (s sdkSpec) specified() bool {
-	return s.valid() && s.kind != sdkPrivate
-}
-
-// whether the API surface is managed and versioned, i.e. has .txt file that
-// get frozen on SDK freeze and changes get reviewed by API council.
-func (s sdkSpec) stable() bool {
-	if !s.specified() {
-		return false
-	}
-	switch s.kind {
-	case sdkNone:
-		// there is nothing to manage and version in this case; de facto stable API.
-		return true
-	case sdkCore, sdkPublic, sdkSystem, sdkModule, sdkSystemServer:
-		return true
-	case sdkCorePlatform, sdkTest, sdkPrivate:
-		return false
-	default:
-		panic(fmt.Errorf("unknown sdkKind=%v", s.kind))
-	}
-	return false
-}
-
-// prebuiltSdkAvailableForUnbundledBuilt tells whether this sdkSpec can have a prebuilt SDK
-// that can be used for unbundled builds.
-func (s sdkSpec) prebuiltSdkAvailableForUnbundledBuild() bool {
-	// "", "none", and "core_platform" are not available for unbundled build
-	// as we don't/can't have prebuilt stub for the versions
-	return s.kind != sdkPrivate && s.kind != sdkNone && s.kind != sdkCorePlatform
-}
-
-func (s sdkSpec) forVendorPartition(ctx android.EarlyModuleContext) sdkSpec {
-	// If BOARD_CURRENT_API_LEVEL_FOR_VENDOR_MODULES has a numeric value,
-	// use it instead of "current" for the vendor partition.
-	currentSdkVersion := ctx.DeviceConfig().CurrentApiLevelForVendorModules()
-	if currentSdkVersion == "current" {
-		return s
-	}
-
-	if s.kind == sdkPublic || s.kind == sdkSystem {
-		if s.version.isCurrent() {
-			if i, err := strconv.Atoi(currentSdkVersion); err == nil {
-				version := sdkVersion(i)
-				return sdkSpec{s.kind, version, s.raw}
-			}
-			panic(fmt.Errorf("BOARD_CURRENT_API_LEVEL_FOR_VENDOR_MODULES must be either \"current\" or a number, but was %q", currentSdkVersion))
-		}
-	}
-	return s
-}
-
-// usePrebuilt determines whether prebuilt SDK should be used for this sdkSpec with the given context.
-func (s sdkSpec) usePrebuilt(ctx android.EarlyModuleContext) bool {
-	if s.version.isCurrent() {
-		// "current" can be built from source and be from prebuilt SDK
-		return ctx.Config().AlwaysUsePrebuiltSdks()
-	} else if s.version.isNumbered() {
-		// validation check
-		if s.kind != sdkPublic && s.kind != sdkSystem && s.kind != sdkTest && s.kind != sdkModule {
-			panic(fmt.Errorf("prebuilt SDK is not not available for sdkKind=%q", s.kind))
-			return false
-		}
-		// numbered SDKs are always from prebuilt
-		return true
-	}
-	// "", "none", "core_platform" fall here
-	return false
-}
-
-// effectiveVersion converts an sdkSpec into the concrete sdkVersion that the module
-// should use. For modules targeting an unreleased SDK (meaning it does not yet have a number)
-// it returns android.FutureApiLevel(10000).
-func (s sdkSpec) effectiveVersion(ctx android.EarlyModuleContext) (sdkVersion, error) {
-	if !s.valid() {
-		return s.version, fmt.Errorf("invalid sdk version %q", s.raw)
-	}
-
-	if ctx.DeviceSpecific() || ctx.SocSpecific() {
-		s = s.forVendorPartition(ctx)
-	}
-	if s.version.isNumbered() {
-		return s.version, nil
-	}
-	return sdkVersion(ctx.Config().DefaultAppTargetSdk(ctx).FinalOrFutureInt()), nil
-}
-
-// effectiveVersionString converts an sdkSpec into the concrete version string that the module
-// should use. For modules targeting an unreleased SDK (meaning it does not yet have a number)
-// it returns the codename (P, Q, R, etc.)
-func (s sdkSpec) effectiveVersionString(ctx android.EarlyModuleContext) (string, error) {
-	ver, err := s.effectiveVersion(ctx)
-	if err == nil && int(ver) == ctx.Config().DefaultAppTargetSdk(ctx).FinalOrFutureInt() {
-		return ctx.Config().DefaultAppTargetSdk(ctx).String(), nil
-	}
-	return ver.String(), err
-}
-
-func (s sdkSpec) defaultJavaLanguageVersion(ctx android.EarlyModuleContext) javaVersion {
-	sdk, err := s.effectiveVersion(ctx)
+func defaultJavaLanguageVersion(ctx android.EarlyModuleContext, s android.SdkSpec) javaVersion {
+	sdk, err := s.EffectiveVersion(ctx)
 	if err != nil {
 		ctx.PropertyErrorf("sdk_version", "%s", err)
 	}
@@ -275,103 +60,27 @@
 	}
 }
 
-func sdkSpecFrom(str string) sdkSpec {
-	switch str {
-	// special cases first
-	case "":
-		return sdkSpec{sdkPrivate, sdkVersionNone, str}
-	case "none":
-		return sdkSpec{sdkNone, sdkVersionNone, str}
-	case "core_platform":
-		return sdkSpec{sdkCorePlatform, sdkVersionNone, str}
-	default:
-		// the syntax is [kind_]version
-		sep := strings.LastIndex(str, "_")
-
-		var kindString string
-		if sep == 0 {
-			return sdkSpec{sdkInvalid, sdkVersionNone, str}
-		} else if sep == -1 {
-			kindString = ""
-		} else {
-			kindString = str[0:sep]
-		}
-		versionString := str[sep+1 : len(str)]
-
-		var kind sdkKind
-		switch kindString {
-		case "":
-			kind = sdkPublic
-		case "core":
-			kind = sdkCore
-		case "system":
-			kind = sdkSystem
-		case "test":
-			kind = sdkTest
-		case "module":
-			kind = sdkModule
-		case "system_server":
-			kind = sdkSystemServer
-		default:
-			return sdkSpec{sdkInvalid, sdkVersionNone, str}
-		}
-
-		var version sdkVersion
-		if versionString == "current" {
-			version = sdkVersionCurrent
-		} else if i, err := strconv.Atoi(versionString); err == nil {
-			version = sdkVersion(i)
-		} else {
-			return sdkSpec{sdkInvalid, sdkVersionNone, str}
-		}
-
-		return sdkSpec{kind, version, str}
-	}
-}
-
-func (s sdkSpec) validateSystemSdk(ctx android.EarlyModuleContext) bool {
-	// Ensures that the specified system SDK version is one of BOARD_SYSTEMSDK_VERSIONS (for vendor/product Java module)
-	// Assuming that BOARD_SYSTEMSDK_VERSIONS := 28 29,
-	// sdk_version of the modules in vendor/product that use system sdk must be either system_28, system_29 or system_current
-	if s.kind != sdkSystem || !s.version.isNumbered() {
-		return true
-	}
-	allowedVersions := ctx.DeviceConfig().PlatformSystemSdkVersions()
-	if ctx.DeviceSpecific() || ctx.SocSpecific() || (ctx.ProductSpecific() && ctx.Config().EnforceProductPartitionInterface()) {
-		systemSdkVersions := ctx.DeviceConfig().SystemSdkVersions()
-		if len(systemSdkVersions) > 0 {
-			allowedVersions = systemSdkVersions
-		}
-	}
-	if len(allowedVersions) > 0 && !android.InList(s.version.String(), allowedVersions) {
-		ctx.PropertyErrorf("sdk_version", "incompatible sdk version %q. System SDK version should be one of %q",
-			s.raw, allowedVersions)
-		return false
-	}
-	return true
-}
-
-func decodeSdkDep(ctx android.EarlyModuleContext, sdkContext sdkContext) sdkDep {
-	sdkVersion := sdkContext.sdkVersion()
-	if !sdkVersion.valid() {
-		ctx.PropertyErrorf("sdk_version", "invalid version %q", sdkVersion.raw)
+func decodeSdkDep(ctx android.EarlyModuleContext, sdkContext android.SdkContext) sdkDep {
+	sdkVersion := sdkContext.SdkVersion()
+	if !sdkVersion.Valid() {
+		ctx.PropertyErrorf("sdk_version", "invalid version %q", sdkVersion.Raw)
 		return sdkDep{}
 	}
 
 	if ctx.DeviceSpecific() || ctx.SocSpecific() {
-		sdkVersion = sdkVersion.forVendorPartition(ctx)
+		sdkVersion = sdkVersion.ForVendorPartition(ctx)
 	}
 
-	if !sdkVersion.validateSystemSdk(ctx) {
+	if !sdkVersion.ValidateSystemSdk(ctx) {
 		return sdkDep{}
 	}
 
-	if sdkVersion.usePrebuilt(ctx) {
-		dir := filepath.Join("prebuilts", "sdk", sdkVersion.version.String(), sdkVersion.kind.String())
+	if sdkVersion.UsePrebuilt(ctx) {
+		dir := filepath.Join("prebuilts", "sdk", sdkVersion.Version.String(), sdkVersion.Kind.String())
 		jar := filepath.Join(dir, "android.jar")
 		// There's no aidl for other SDKs yet.
 		// TODO(77525052): Add aidl files for other SDKs too.
-		publicDir := filepath.Join("prebuilts", "sdk", sdkVersion.version.String(), "public")
+		publicDir := filepath.Join("prebuilts", "sdk", sdkVersion.Version.String(), "public")
 		aidl := filepath.Join(publicDir, "framework.aidl")
 		jarPath := android.ExistentPathForSource(ctx, jar)
 		aidlPath := android.ExistentPathForSource(ctx, aidl)
@@ -380,23 +89,23 @@
 		if (!jarPath.Valid() || !aidlPath.Valid()) && ctx.Config().AllowMissingDependencies() {
 			return sdkDep{
 				invalidVersion: true,
-				bootclasspath:  []string{fmt.Sprintf("sdk_%s_%s_android", sdkVersion.kind, sdkVersion.version.String())},
+				bootclasspath:  []string{fmt.Sprintf("sdk_%s_%s_android", sdkVersion.Kind, sdkVersion.Version.String())},
 			}
 		}
 
 		if !jarPath.Valid() {
-			ctx.PropertyErrorf("sdk_version", "invalid sdk version %q, %q does not exist", sdkVersion.raw, jar)
+			ctx.PropertyErrorf("sdk_version", "invalid sdk version %q, %q does not exist", sdkVersion.Raw, jar)
 			return sdkDep{}
 		}
 
 		if !aidlPath.Valid() {
-			ctx.PropertyErrorf("sdk_version", "invalid sdk version %q, %q does not exist", sdkVersion.raw, aidl)
+			ctx.PropertyErrorf("sdk_version", "invalid sdk version %q, %q does not exist", sdkVersion.Raw, aidl)
 			return sdkDep{}
 		}
 
 		var systemModules string
-		if sdkVersion.defaultJavaLanguageVersion(ctx).usesJavaModules() {
-			systemModules = "sdk_public_" + sdkVersion.version.String() + "_system_modules"
+		if defaultJavaLanguageVersion(ctx, sdkVersion).usesJavaModules() {
+			systemModules = "sdk_public_" + sdkVersion.Version.String() + "_system_modules"
 		}
 
 		return sdkDep{
@@ -418,8 +127,8 @@
 		}
 	}
 
-	switch sdkVersion.kind {
-	case sdkPrivate:
+	switch sdkVersion.Kind {
+	case android.SdkPrivate:
 		return sdkDep{
 			useModule:          true,
 			systemModules:      corePlatformSystemModules(ctx),
@@ -427,8 +136,8 @@
 			classpath:          config.FrameworkLibraries,
 			frameworkResModule: "framework-res",
 		}
-	case sdkNone:
-		systemModules := sdkContext.systemModules()
+	case android.SdkNone:
+		systemModules := sdkContext.SystemModules()
 		if systemModules == "" {
 			ctx.PropertyErrorf("sdk_version",
 				`system_modules is required to be set to a non-empty value when sdk_version is "none", did you mean sdk_version: "core_platform"?`)
@@ -444,34 +153,34 @@
 			systemModules:  systemModules,
 			bootclasspath:  []string{systemModules},
 		}
-	case sdkCorePlatform:
+	case android.SdkCorePlatform:
 		return sdkDep{
 			useModule:        true,
 			systemModules:    corePlatformSystemModules(ctx),
 			bootclasspath:    corePlatformBootclasspathLibraries(ctx),
 			noFrameworksLibs: true,
 		}
-	case sdkPublic:
+	case android.SdkPublic:
 		return toModule([]string{"android_stubs_current"}, "framework-res", sdkFrameworkAidlPath(ctx))
-	case sdkSystem:
+	case android.SdkSystem:
 		return toModule([]string{"android_system_stubs_current"}, "framework-res", sdkFrameworkAidlPath(ctx))
-	case sdkTest:
+	case android.SdkTest:
 		return toModule([]string{"android_test_stubs_current"}, "framework-res", sdkFrameworkAidlPath(ctx))
-	case sdkCore:
+	case android.SdkCore:
 		return sdkDep{
 			useModule:        true,
 			bootclasspath:    []string{"core.current.stubs", config.DefaultLambdaStubsLibrary},
 			systemModules:    "core-current-stubs-system-modules",
 			noFrameworksLibs: true,
 		}
-	case sdkModule:
+	case android.SdkModule:
 		// TODO(146757305): provide .apk and .aidl that have more APIs for modules
 		return toModule([]string{"android_module_lib_stubs_current"}, "framework-res", nonUpdatableFrameworkAidlPath(ctx))
-	case sdkSystemServer:
+	case android.SdkSystemServer:
 		// TODO(146757305): provide .apk and .aidl that have more APIs for modules
 		return toModule([]string{"android_system_server_stubs_current"}, "framework-res", sdkFrameworkAidlPath(ctx))
 	default:
-		panic(fmt.Errorf("invalid sdk %q", sdkVersion.raw))
+		panic(fmt.Errorf("invalid sdk %q", sdkVersion.Raw))
 	}
 }
 
diff --git a/java/sdk_library.go b/java/sdk_library.go
index e1ca77d..ebb2154 100644
--- a/java/sdk_library.go
+++ b/java/sdk_library.go
@@ -814,22 +814,22 @@
 	return nil
 }
 
-func (c *commonToSdkLibraryAndImport) selectHeaderJarsForSdkVersion(ctx android.BaseModuleContext, sdkVersion sdkSpec) android.Paths {
+func (c *commonToSdkLibraryAndImport) selectHeaderJarsForSdkVersion(ctx android.BaseModuleContext, sdkVersion android.SdkSpec) android.Paths {
 
 	// If a specific numeric version has been requested then use prebuilt versions of the sdk.
-	if sdkVersion.version.isNumbered() {
+	if sdkVersion.Version.IsNumbered() {
 		return PrebuiltJars(ctx, c.moduleBase.BaseModuleName(), sdkVersion)
 	}
 
 	var apiScope *apiScope
-	switch sdkVersion.kind {
-	case sdkSystem:
+	switch sdkVersion.Kind {
+	case android.SdkSystem:
 		apiScope = apiScopeSystem
-	case sdkModule:
+	case android.SdkModule:
 		apiScope = apiScopeModuleLib
-	case sdkTest:
+	case android.SdkTest:
 		apiScope = apiScopeTest
-	case sdkSystemServer:
+	case android.SdkSystemServer:
 		apiScope = apiScopeSystemServer
 	default:
 		apiScope = apiScopePublic
@@ -932,14 +932,14 @@
 	//
 	// These are turbine generated jars so they only change if the externals of the
 	// class changes but it does not contain and implementation or JavaDoc.
-	SdkHeaderJars(ctx android.BaseModuleContext, sdkVersion sdkSpec) android.Paths
+	SdkHeaderJars(ctx android.BaseModuleContext, sdkVersion android.SdkSpec) android.Paths
 
 	// Get the implementation jars appropriate for the supplied sdk version.
 	//
 	// These are either the implementation jar for the whole sdk library or the implementation
 	// jars for the stubs. The latter should only be needed when generating JavaDoc as otherwise
 	// they are identical to the corresponding header jars.
-	SdkImplementationJars(ctx android.BaseModuleContext, sdkVersion sdkSpec) android.Paths
+	SdkImplementationJars(ctx android.BaseModuleContext, sdkVersion android.SdkSpec) android.Paths
 }
 
 type SdkLibrary struct {
@@ -1147,7 +1147,7 @@
 		return proptools.String(scopeProperties.Sdk_version)
 	}
 
-	sdkDep := decodeSdkDep(mctx, sdkContext(&module.Library))
+	sdkDep := decodeSdkDep(mctx, android.SdkContext(&module.Library))
 	if sdkDep.hasStandardLibs() {
 		// If building against a standard sdk then use the sdk version appropriate for the scope.
 		return apiScope.sdkVersion
@@ -1465,17 +1465,17 @@
 	mctx.CreateModule(sdkLibraryXmlFactory, &props)
 }
 
-func PrebuiltJars(ctx android.BaseModuleContext, baseName string, s sdkSpec) android.Paths {
-	var ver sdkVersion
-	var kind sdkKind
-	if s.usePrebuilt(ctx) {
-		ver = s.version
-		kind = s.kind
+func PrebuiltJars(ctx android.BaseModuleContext, baseName string, s android.SdkSpec) android.Paths {
+	var ver android.SdkVersion
+	var kind android.SdkKind
+	if s.UsePrebuilt(ctx) {
+		ver = s.Version
+		kind = s.Kind
 	} else {
 		// We don't have prebuilt SDK for the specific sdkVersion.
 		// Instead of breaking the build, fallback to use "system_current"
-		ver = sdkVersionCurrent
-		kind = sdkSystem
+		ver = android.SdkVersionCurrent
+		kind = android.SdkSystem
 	}
 
 	dir := filepath.Join("prebuilts", "sdk", ver.String(), kind.String())
@@ -1485,7 +1485,7 @@
 		if ctx.Config().AllowMissingDependencies() {
 			return android.Paths{android.PathForSource(ctx, jar)}
 		} else {
-			ctx.PropertyErrorf("sdk_library", "invalid sdk version %q, %q does not exist", s.raw, jar)
+			ctx.PropertyErrorf("sdk_library", "invalid sdk version %q, %q does not exist", s.Raw, jar)
 		}
 		return nil
 	}
@@ -1502,13 +1502,13 @@
 	return len(otherApexInfo.InApexes) > 0 && reflect.DeepEqual(apexInfo.InApexes, otherApexInfo.InApexes)
 }
 
-func (module *SdkLibrary) sdkJars(ctx android.BaseModuleContext, sdkVersion sdkSpec, headerJars bool) android.Paths {
+func (module *SdkLibrary) sdkJars(ctx android.BaseModuleContext, sdkVersion android.SdkSpec, headerJars bool) android.Paths {
 	// If the client doesn't set sdk_version, but if this library prefers stubs over
 	// the impl library, let's provide the widest API surface possible. To do so,
 	// force override sdk_version to module_current so that the closest possible API
 	// surface could be found in selectHeaderJarsForSdkVersion
-	if module.defaultsToStubs() && !sdkVersion.specified() {
-		sdkVersion = sdkSpecFrom("module_current")
+	if module.defaultsToStubs() && !sdkVersion.Specified() {
+		sdkVersion = android.SdkSpecFrom("module_current")
 	}
 
 	// Only provide access to the implementation library if it is actually built.
@@ -1518,7 +1518,7 @@
 		// Only allow access to the implementation library in the following condition:
 		// * No sdk_version specified on the referencing module.
 		// * The referencing module is in the same apex as this.
-		if sdkVersion.kind == sdkPrivate || withinSameApexesAs(ctx, module) {
+		if sdkVersion.Kind == android.SdkPrivate || withinSameApexesAs(ctx, module) {
 			if headerJars {
 				return module.HeaderJars()
 			} else {
@@ -1531,12 +1531,12 @@
 }
 
 // to satisfy SdkLibraryDependency interface
-func (module *SdkLibrary) SdkHeaderJars(ctx android.BaseModuleContext, sdkVersion sdkSpec) android.Paths {
+func (module *SdkLibrary) SdkHeaderJars(ctx android.BaseModuleContext, sdkVersion android.SdkSpec) android.Paths {
 	return module.sdkJars(ctx, sdkVersion, true /*headerJars*/)
 }
 
 // to satisfy SdkLibraryDependency interface
-func (module *SdkLibrary) SdkImplementationJars(ctx android.BaseModuleContext, sdkVersion sdkSpec) android.Paths {
+func (module *SdkLibrary) SdkImplementationJars(ctx android.BaseModuleContext, sdkVersion android.SdkSpec) android.Paths {
 	return module.sdkJars(ctx, sdkVersion, false /*headerJars*/)
 }
 
@@ -1568,7 +1568,7 @@
 
 	// If this builds against standard libraries (i.e. is not part of the core libraries)
 	// then assume it provides both system and test apis.
-	sdkDep := decodeSdkDep(mctx, sdkContext(&module.Library))
+	sdkDep := decodeSdkDep(mctx, android.SdkContext(&module.Library))
 	hasSystemAndTestApis := sdkDep.hasStandardLibs()
 	module.sdkLibraryProperties.Generate_system_and_test_apis = hasSystemAndTestApis
 
@@ -2069,7 +2069,7 @@
 	}
 }
 
-func (module *SdkLibraryImport) sdkJars(ctx android.BaseModuleContext, sdkVersion sdkSpec, headerJars bool) android.Paths {
+func (module *SdkLibraryImport) sdkJars(ctx android.BaseModuleContext, sdkVersion android.SdkSpec, headerJars bool) android.Paths {
 
 	// For consistency with SdkLibrary make the implementation jar available to libraries that
 	// are within the same APEX.
@@ -2086,13 +2086,13 @@
 }
 
 // to satisfy SdkLibraryDependency interface
-func (module *SdkLibraryImport) SdkHeaderJars(ctx android.BaseModuleContext, sdkVersion sdkSpec) android.Paths {
+func (module *SdkLibraryImport) SdkHeaderJars(ctx android.BaseModuleContext, sdkVersion android.SdkSpec) android.Paths {
 	// This module is just a wrapper for the prebuilt stubs.
 	return module.sdkJars(ctx, sdkVersion, true)
 }
 
 // to satisfy SdkLibraryDependency interface
-func (module *SdkLibraryImport) SdkImplementationJars(ctx android.BaseModuleContext, sdkVersion sdkSpec) android.Paths {
+func (module *SdkLibraryImport) SdkImplementationJars(ctx android.BaseModuleContext, sdkVersion android.SdkSpec) android.Paths {
 	// This module is just a wrapper for the stubs.
 	return module.sdkJars(ctx, sdkVersion, false)
 }
diff --git a/scripts/toc.sh b/scripts/toc.sh
index 8b1d25f..c6b7866 100755
--- a/scripts/toc.sh
+++ b/scripts/toc.sh
@@ -17,7 +17,7 @@
 # Script to handle generating a .toc file from a .so file
 # Inputs:
 #  Environment:
-#   CROSS_COMPILE: prefix added to readelf tool
+#   CLANG_BIN: path to the clang bin directory
 #  Arguments:
 #   -i ${file}: input file (required)
 #   -o ${file}: output file (required)
@@ -35,34 +35,34 @@
 }
 
 do_elf() {
-    ("${CROSS_COMPILE}readelf" -d "${infile}" | grep SONAME || echo "No SONAME for ${infile}") > "${outfile}.tmp"
-    "${CROSS_COMPILE}readelf" --dyn-syms "${infile}" | awk '{$2=""; $3=""; print}' >> "${outfile}.tmp"
+    ("${CLANG_BIN}/llvm-readelf" -d "${infile}" | grep SONAME || echo "No SONAME for ${infile}") > "${outfile}.tmp"
+    "${CLANG_BIN}/llvm-readelf" --dyn-syms "${infile}" | awk '{$2=""; $3=""; print}' >> "${outfile}.tmp"
 
     cat <<EOF > "${depsfile}"
 ${outfile}: \\
-  ${CROSS_COMPILE}readelf \\
+  ${CLANG_BIN}/llvm-readelf \\
 EOF
 }
 
 do_macho() {
-    "${CROSS_COMPILE}/otool" -l "${infile}" | grep LC_ID_DYLIB -A 5 > "${outfile}.tmp"
-    "${CROSS_COMPILE}/nm" -gP "${infile}" | cut -f1-2 -d" " | (grep -v 'U$' >> "${outfile}.tmp" || true)
+    "${CLANG_BIN}/llvm-objdump" -p "${infile}" | grep LC_ID_DYLIB -A 5 > "${outfile}.tmp"
+    "${CLANG_BIN}/llvm-nm" -gP "${infile}" | cut -f1-2 -d" " | (grep -v 'U$' >> "${outfile}.tmp" || true)
 
     cat <<EOF > "${depsfile}"
 ${outfile}: \\
-  ${CROSS_COMPILE}/otool \\
-  ${CROSS_COMPILE}/nm \\
+  ${CLANG_BIN}/llvm-objdump \\
+  ${CLANG_BIN}/llvm-nm \\
 EOF
 }
 
 do_pe() {
-    "${CROSS_COMPILE}objdump" -x "${infile}" | grep "^Name" | cut -f3 -d" " > "${outfile}.tmp"
-    "${CROSS_COMPILE}nm" -g -f p "${infile}" | cut -f1-2 -d" " >> "${outfile}.tmp"
+    "${CLANG_BIN}/llvm-objdump" -x "${infile}" | grep "^Name" | cut -f3 -d" " > "${outfile}.tmp"
+    "${CLANG_BIN}/llvm-nm" -gP "${infile}" | cut -f1-2 -d" " >> "${outfile}.tmp"
 
     cat <<EOF > "${depsfile}"
 ${outfile}: \\
-  ${CROSS_COMPILE}objdump \\
-  ${CROSS_COMPILE}nm \\
+  ${CLANG_BIN}/llvm-objdump \\
+  ${CLANG_BIN}/llvm-nm \\
 EOF
 }
 
@@ -98,8 +98,8 @@
     usage
 fi
 
-if [ -z "${CROSS_COMPILE:-}" ]; then
-    echo "CROSS_COMPILE environment variable must be set"
+if [ -z "${CLANG_BIN:-}" ]; then
+    echo "CLANG_BIN environment variable must be set"
     usage
 fi
 
@@ -107,7 +107,7 @@
 
 cat <<EOF > "${depsfile}"
 ${outfile}: \\
-  ${CROSS_COMPILE}readelf \\
+  ${CLANG_BIN}/llvm-readelf \\
 EOF
 
 if [ -n "${elf:-}" ]; then
diff --git a/sysprop/sysprop_test.go b/sysprop/sysprop_test.go
index e9d9051..f42f9e9 100644
--- a/sysprop/sysprop_test.go
+++ b/sysprop/sysprop_test.go
@@ -371,6 +371,6 @@
 	android.AssertStringEquals(t, "min_sdk_version forwarding to cc module", "29", propFromCc)
 
 	javaModule := result.ModuleForTests("sysprop-platform", "android_common").Module().(*java.Library)
-	propFromJava := javaModule.MinSdkVersion()
+	propFromJava := javaModule.MinSdkVersionString()
 	android.AssertStringEquals(t, "min_sdk_version forwarding to java module", "30", propFromJava)
 }
diff --git a/ui/build/bazel.go b/ui/build/bazel.go
index ec561d5..0ebfcd8 100644
--- a/ui/build/bazel.go
+++ b/ui/build/bazel.go
@@ -149,6 +149,9 @@
 		cmd.Args = append(cmd.Args, "--action_env=PATH="+pathEnvValue)
 	}
 
+	// Allow Bazel actions to see the SHELL variable (passed to Bazel above)
+	cmd.Args = append(cmd.Args, "--action_env=SHELL")
+
 	// Append custom build flags to the Bazel command. Changes to these flags
 	// may invalidate Bazel's analysis cache.
 	// These should be appended as the final args, so that they take precedence.