Merge "Stop exporting systemserverclasspath_fragment when targeting S" into tm-dev am: 0147aca453

Original change: https://googleplex-android-review.googlesource.com/c/platform/build/soong/+/19135262

Change-Id: I9039499819e938deb9d13557bdee26fc56bd6f4c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/android/defaults.go b/android/defaults.go
index 8b121f6..54f44bc 100644
--- a/android/defaults.go
+++ b/android/defaults.go
@@ -15,6 +15,8 @@
 package android
 
 import (
+	"bytes"
+	"fmt"
 	"reflect"
 
 	"github.com/google/blueprint"
@@ -67,9 +69,11 @@
 	// Set the property structures into which defaults will be added.
 	setProperties(props []interface{}, variableProperties interface{})
 
-	// Apply defaults from the supplied Defaults to the property structures supplied to
+	// Apply defaults from the supplied DefaultsModule to the property structures supplied to
 	// setProperties(...).
-	applyDefaults(TopDownMutatorContext, []Defaults)
+	applyDefaults(TopDownMutatorContext, []DefaultsModule)
+
+	applySingleDefaultsWithTracker(EarlyModuleContext, DefaultsModule, defaultsTrackerFunc)
 
 	// Set the hook to be called after any defaults have been applied.
 	//
@@ -115,9 +119,23 @@
 	Defaults_visibility []string
 }
 
+// AdditionalDefaultsProperties contains properties of defaults modules which
+// can have other defaults applied.
+type AdditionalDefaultsProperties struct {
+
+	// The list of properties set by the default whose values must not be changed by any module that
+	// applies these defaults. It is an error if a property is not supported by the defaults module or
+	// has not been set to a non-zero value. If this contains "*" then that must be the only entry in
+	// which case all properties that are set on this defaults will be protected (except the
+	// protected_properties and visibility.
+	Protected_properties []string
+}
+
 type DefaultsModuleBase struct {
 	DefaultableModuleBase
 
+	defaultsProperties AdditionalDefaultsProperties
+
 	// Included to support setting bazel_module.label for multiple Soong modules to the same Bazel
 	// target. This is primarily useful for modules that were architecture specific and instead are
 	// handled in Bazel as a select().
@@ -151,6 +169,18 @@
 	// DefaultsModuleBase will type-assert to the Defaults interface.
 	isDefaults() bool
 
+	// additionalDefaultableProperties returns additional properties provided by the defaults which
+	// can themselves have defaults applied.
+	additionalDefaultableProperties() []interface{}
+
+	// protectedProperties returns the names of the properties whose values cannot be changed by a
+	// module that applies these defaults.
+	protectedProperties() []string
+
+	// setProtectedProperties sets the names of the properties whose values cannot be changed by a
+	// module that applies these defaults.
+	setProtectedProperties(protectedProperties []string)
+
 	// Get the structures containing the properties for which defaults can be provided.
 	properties() []interface{}
 
@@ -167,6 +197,18 @@
 	Bazelable
 }
 
+func (d *DefaultsModuleBase) additionalDefaultableProperties() []interface{} {
+	return []interface{}{&d.defaultsProperties}
+}
+
+func (d *DefaultsModuleBase) protectedProperties() []string {
+	return d.defaultsProperties.Protected_properties
+}
+
+func (d *DefaultsModuleBase) setProtectedProperties(protectedProperties []string) {
+	d.defaultsProperties.Protected_properties = protectedProperties
+}
+
 func (d *DefaultsModuleBase) properties() []interface{} {
 	return d.defaultableProperties
 }
@@ -190,6 +232,10 @@
 		&ApexProperties{},
 		&distProperties{})
 
+	// Additional properties of defaults modules that can themselves have
+	// defaults applied.
+	module.AddProperties(module.additionalDefaultableProperties()...)
+
 	// Bazel module must be initialized _before_ Defaults to be included in cc_defaults module.
 	InitBazelModule(module)
 	initAndroidModuleBase(module)
@@ -218,6 +264,57 @@
 	// The applicable licenses property for defaults is 'licenses'.
 	setPrimaryLicensesProperty(module, "licenses", &commonProperties.Licenses)
 
+	AddLoadHook(module, func(ctx LoadHookContext) {
+
+		protectedProperties := module.protectedProperties()
+		if len(protectedProperties) == 0 {
+			return
+		}
+
+		propertiesAvailable := map[string]struct{}{}
+		propertiesSet := map[string]struct{}{}
+
+		// A defaults tracker which will keep track of which properties have been set on this module.
+		collector := func(defaults DefaultsModule, property string, dstValue interface{}, srcValue interface{}) bool {
+			value := reflect.ValueOf(dstValue)
+			propertiesAvailable[property] = struct{}{}
+			if !value.IsZero() {
+				propertiesSet[property] = struct{}{}
+			}
+			// Skip all the properties so that there are no changes to the defaults.
+			return false
+		}
+
+		// Try and apply this module's defaults to itself, so that the properties can be collected but
+		// skip all the properties so it doesn't actually do anything.
+		module.applySingleDefaultsWithTracker(ctx, module, collector)
+
+		if InList("*", protectedProperties) {
+			if len(protectedProperties) != 1 {
+				ctx.PropertyErrorf("protected_properties", `if specified then "*" must be the only property listed`)
+				return
+			}
+
+			// Do not automatically protect the protected_properties property.
+			delete(propertiesSet, "protected_properties")
+
+			// Or the visibility property.
+			delete(propertiesSet, "visibility")
+
+			// Replace the "*" with the names of all the properties that have been set.
+			protectedProperties = SortedStringKeys(propertiesSet)
+			module.setProtectedProperties(protectedProperties)
+		} else {
+			for _, property := range protectedProperties {
+				if _, ok := propertiesAvailable[property]; !ok {
+					ctx.PropertyErrorf(property, "property is not supported by this module type %q",
+						ctx.ModuleType())
+				} else if _, ok := propertiesSet[property]; !ok {
+					ctx.PropertyErrorf(property, "is not set; protected properties must be explicitly set")
+				}
+			}
+		}
+	})
 }
 
 var _ Defaults = (*DefaultsModuleBase)(nil)
@@ -269,35 +366,204 @@
 	b.setNamespacedVariableProps(dst)
 }
 
+// defaultValueInfo contains information about each default value that applies to a protected
+// property.
+type defaultValueInfo struct {
+	// The DefaultsModule providing the value, which may be defined on that module or applied as a
+	// default from other modules.
+	module Module
+
+	// The default value, as returned by getComparableValue
+	defaultValue reflect.Value
+}
+
+// protectedPropertyInfo contains information about each property that has to be protected when
+// applying defaults.
+type protectedPropertyInfo struct {
+	// True if the property was set on the module to which defaults are applied, this is an error.
+	propertySet bool
+
+	// The original value of the property on the module, as returned by getComparableValue.
+	originalValue reflect.Value
+
+	// A list of defaults for the property that are being applied.
+	defaultValues []defaultValueInfo
+}
+
+// getComparableValue takes a reflect.Value that may be a pointer to another value and returns a
+// reflect.Value to the underlying data or the original if was not a pointer or was nil. The
+// returned values can then be compared for equality.
+func getComparableValue(value reflect.Value) reflect.Value {
+	if value.IsZero() {
+		return value
+	}
+	for value.Kind() == reflect.Ptr {
+		value = value.Elem()
+	}
+	return value
+}
+
 func (defaultable *DefaultableModuleBase) applyDefaults(ctx TopDownMutatorContext,
-	defaultsList []Defaults) {
+	defaultsList []DefaultsModule) {
+
+	// Collate information on all the properties protected by each of the default modules applied
+	// to this module.
+	allProtectedProperties := map[string]*protectedPropertyInfo{}
+	for _, defaults := range defaultsList {
+		for _, property := range defaults.protectedProperties() {
+			info := allProtectedProperties[property]
+			if info == nil {
+				info = &protectedPropertyInfo{}
+				allProtectedProperties[property] = info
+			}
+		}
+	}
+
+	// If there are any protected properties then collate information about attempts to change them.
+	var protectedPropertyInfoCollector defaultsTrackerFunc
+	if len(allProtectedProperties) > 0 {
+		protectedPropertyInfoCollector = func(defaults DefaultsModule, property string,
+			dstValue interface{}, srcValue interface{}) bool {
+
+			// If the property is not protected then return immediately.
+			info := allProtectedProperties[property]
+			if info == nil {
+				return true
+			}
+
+			currentValue := reflect.ValueOf(dstValue)
+			if info.defaultValues == nil {
+				info.propertySet = !currentValue.IsZero()
+				info.originalValue = getComparableValue(currentValue)
+			}
+
+			defaultValue := reflect.ValueOf(srcValue)
+			if !defaultValue.IsZero() {
+				info.defaultValues = append(info.defaultValues,
+					defaultValueInfo{defaults, getComparableValue(defaultValue)})
+			}
+
+			return true
+		}
+	}
 
 	for _, defaults := range defaultsList {
 		if ctx.Config().runningAsBp2Build {
 			applyNamespacedVariableDefaults(defaults, ctx)
 		}
-		for _, prop := range defaultable.defaultableProperties {
-			if prop == defaultable.defaultableVariableProperties {
-				defaultable.applyDefaultVariableProperties(ctx, defaults, prop)
-			} else {
-				defaultable.applyDefaultProperties(ctx, defaults, prop)
+
+		defaultable.applySingleDefaultsWithTracker(ctx, defaults, protectedPropertyInfoCollector)
+	}
+
+	// Check the status of any protected properties.
+	for property, info := range allProtectedProperties {
+		if len(info.defaultValues) == 0 {
+			// No defaults were applied to the protected properties. Possibly because this module type
+			// does not support any of them.
+			continue
+		}
+
+		// Check to make sure that there are no conflicts between the defaults.
+		conflictingDefaults := false
+		previousDefaultValue := reflect.ValueOf(false)
+		for _, defaultInfo := range info.defaultValues {
+			defaultValue := defaultInfo.defaultValue
+			if previousDefaultValue.IsZero() {
+				previousDefaultValue = defaultValue
+			} else if !reflect.DeepEqual(previousDefaultValue.Interface(), defaultValue.Interface()) {
+				conflictingDefaults = true
+				break
 			}
 		}
+
+		if conflictingDefaults {
+			var buf bytes.Buffer
+			for _, defaultInfo := range info.defaultValues {
+				buf.WriteString(fmt.Sprintf("\n    defaults module %q provides value %#v",
+					ctx.OtherModuleName(defaultInfo.module), defaultInfo.defaultValue))
+			}
+			result := buf.String()
+			ctx.ModuleErrorf("has conflicting default values for protected property %q:%s", property, result)
+			continue
+		}
+
+		// Now check to see whether there the current module tried to override/append to the defaults.
+		if info.propertySet {
+			originalValue := info.originalValue
+			// Just compare against the first defaults.
+			defaultValue := info.defaultValues[0].defaultValue
+			defaults := info.defaultValues[0].module
+
+			if originalValue.Kind() == reflect.Slice {
+				ctx.ModuleErrorf("attempts to append %q to protected property %q's value of %q defined in module %q",
+					originalValue,
+					property,
+					defaultValue,
+					ctx.OtherModuleName(defaults))
+			} else {
+				same := reflect.DeepEqual(originalValue.Interface(), defaultValue.Interface())
+				message := ""
+				if same {
+					message = fmt.Sprintf(" with a matching value (%#v) so this property can simply be removed.", originalValue)
+				} else {
+					message = fmt.Sprintf(" with a different value (override %#v with %#v) so removing the property may necessitate other changes.", defaultValue, originalValue)
+				}
+				ctx.ModuleErrorf("attempts to override protected property %q defined in module %q%s",
+					property,
+					ctx.OtherModuleName(defaults), message)
+			}
+		}
+	}
+}
+
+func (defaultable *DefaultableModuleBase) applySingleDefaultsWithTracker(ctx EarlyModuleContext, defaults DefaultsModule, tracker defaultsTrackerFunc) {
+	for _, prop := range defaultable.defaultableProperties {
+		var err error
+		if prop == defaultable.defaultableVariableProperties {
+			err = defaultable.applyDefaultVariableProperties(defaults, prop, tracker)
+		} else {
+			err = defaultable.applyDefaultProperties(defaults, prop, tracker)
+		}
+		if err != nil {
+			if propertyErr, ok := err.(*proptools.ExtendPropertyError); ok {
+				ctx.PropertyErrorf(propertyErr.Property, "%s", propertyErr.Err.Error())
+			} else {
+				panic(err)
+			}
+		}
+	}
+}
+
+// defaultsTrackerFunc is the type of a function that can be used to track how defaults are applied.
+type defaultsTrackerFunc func(defaults DefaultsModule, property string,
+	dstValue interface{}, srcValue interface{}) bool
+
+// filterForTracker wraps a defaultsTrackerFunc in a proptools.ExtendPropertyFilterFunc
+func filterForTracker(defaults DefaultsModule, tracker defaultsTrackerFunc) proptools.ExtendPropertyFilterFunc {
+	if tracker == nil {
+		return nil
+	}
+	return func(property string,
+		dstField, srcField reflect.StructField,
+		dstValue, srcValue interface{}) (bool, error) {
+
+		apply := tracker(defaults, property, dstValue, srcValue)
+		return apply, nil
 	}
 }
 
 // Product variable properties need special handling, the type of the filtered product variable
 // property struct may not be identical between the defaults module and the defaultable module.
 // Use PrependMatchingProperties to apply whichever properties match.
-func (defaultable *DefaultableModuleBase) applyDefaultVariableProperties(ctx TopDownMutatorContext,
-	defaults Defaults, defaultableProp interface{}) {
+func (defaultable *DefaultableModuleBase) applyDefaultVariableProperties(defaults DefaultsModule,
+	defaultableProp interface{}, tracker defaultsTrackerFunc) error {
 	if defaultableProp == nil {
-		return
+		return nil
 	}
 
 	defaultsProp := defaults.productVariableProperties()
 	if defaultsProp == nil {
-		return
+		return nil
 	}
 
 	dst := []interface{}{
@@ -307,31 +573,26 @@
 		proptools.CloneEmptyProperties(reflect.ValueOf(defaultsProp)).Interface(),
 	}
 
-	err := proptools.PrependMatchingProperties(dst, defaultsProp, nil)
-	if err != nil {
-		if propertyErr, ok := err.(*proptools.ExtendPropertyError); ok {
-			ctx.PropertyErrorf(propertyErr.Property, "%s", propertyErr.Err.Error())
-		} else {
-			panic(err)
-		}
-	}
+	filter := filterForTracker(defaults, tracker)
+
+	return proptools.PrependMatchingProperties(dst, defaultsProp, filter)
 }
 
-func (defaultable *DefaultableModuleBase) applyDefaultProperties(ctx TopDownMutatorContext,
-	defaults Defaults, defaultableProp interface{}) {
+func (defaultable *DefaultableModuleBase) applyDefaultProperties(defaults DefaultsModule,
+	defaultableProp interface{}, checker defaultsTrackerFunc) error {
+
+	filter := filterForTracker(defaults, checker)
 
 	for _, def := range defaults.properties() {
 		if proptools.TypeEqual(defaultableProp, def) {
-			err := proptools.PrependProperties(defaultableProp, def, nil)
+			err := proptools.PrependProperties(defaultableProp, def, filter)
 			if err != nil {
-				if propertyErr, ok := err.(*proptools.ExtendPropertyError); ok {
-					ctx.PropertyErrorf(propertyErr.Property, "%s", propertyErr.Err.Error())
-				} else {
-					panic(err)
-				}
+				return err
 			}
 		}
 	}
+
+	return nil
 }
 
 func RegisterDefaultsPreArchMutators(ctx RegisterMutatorsContext) {
@@ -348,12 +609,12 @@
 func defaultsMutator(ctx TopDownMutatorContext) {
 	if defaultable, ok := ctx.Module().(Defaultable); ok {
 		if len(defaultable.defaults().Defaults) > 0 {
-			var defaultsList []Defaults
+			var defaultsList []DefaultsModule
 			seen := make(map[Defaults]bool)
 
 			ctx.WalkDeps(func(module, parent Module) bool {
 				if ctx.OtherModuleDependencyTag(module) == DefaultsDepTag {
-					if defaults, ok := module.(Defaults); ok {
+					if defaults, ok := module.(DefaultsModule); ok {
 						if !seen[defaults] {
 							seen[defaults] = true
 							defaultsList = append(defaultsList, defaults)
diff --git a/android/defaults_test.go b/android/defaults_test.go
index a7542ab..d80f40c 100644
--- a/android/defaults_test.go
+++ b/android/defaults_test.go
@@ -19,7 +19,14 @@
 )
 
 type defaultsTestProperties struct {
-	Foo []string
+	Foo    []string
+	Bar    []string
+	Nested struct {
+		Fizz *bool
+	}
+	Other struct {
+		Buzz *string
+	}
 }
 
 type defaultsTestModule struct {
@@ -130,3 +137,167 @@
 	// TODO: missing transitive defaults is currently not handled
 	_ = missingTransitiveDefaults
 }
+
+func TestProtectedProperties_ProtectedPropertyNotSet(t *testing.T) {
+	bp := `
+		defaults {
+			name: "transitive",
+			protected_properties: ["foo"],
+		}
+	`
+
+	GroupFixturePreparers(
+		prepareForDefaultsTest,
+		FixtureWithRootAndroidBp(bp),
+	).ExtendWithErrorHandler(FixtureExpectsAtLeastOneErrorMatchingPattern(
+		"module \"transitive\": foo: is not set; protected properties must be explicitly set")).
+		RunTest(t)
+}
+
+func TestProtectedProperties_ProtectedPropertyNotLeaf(t *testing.T) {
+	bp := `
+		defaults {
+			name: "transitive",
+			protected_properties: ["nested"],
+			nested: {
+				fizz: true,
+			},
+		}
+	`
+
+	GroupFixturePreparers(
+		prepareForDefaultsTest,
+		FixtureWithRootAndroidBp(bp),
+	).ExtendWithErrorHandler(FixtureExpectsAtLeastOneErrorMatchingPattern(
+		`\Qmodule "transitive": nested: property is not supported by this module type "defaults"\E`)).
+		RunTest(t)
+}
+
+// TestProtectedProperties_ApplyDefaults makes sure that the protected_properties property has
+// defaults applied.
+func TestProtectedProperties_HasDefaultsApplied(t *testing.T) {
+
+	bp := `
+		defaults {
+			name: "transitive",
+			protected_properties: ["foo"],
+			foo: ["transitive"],
+		}
+
+		defaults {
+			name: "defaults",
+			defaults: ["transitive"],
+			protected_properties: ["bar"],
+			bar: ["defaults"],
+		}
+	`
+
+	result := GroupFixturePreparers(
+		prepareForDefaultsTest,
+		FixtureWithRootAndroidBp(bp),
+	).RunTest(t)
+
+	defaults := result.Module("defaults", "").(DefaultsModule)
+	AssertDeepEquals(t, "defaults protected properties", []string{"foo", "bar"}, defaults.protectedProperties())
+}
+
+// TestProtectedProperties_ProtectAllProperties makes sure that protected_properties: ["*"] protects
+// all properties.
+func TestProtectedProperties_ProtectAllProperties(t *testing.T) {
+
+	bp := `
+		defaults {
+			name: "transitive",
+			protected_properties: ["other.buzz"],
+			other: {
+				buzz: "transitive",
+			},
+		}
+
+		defaults {
+			name: "defaults",
+			defaults: ["transitive"],
+			visibility: ["//visibility:private"],
+			protected_properties: ["*"],
+			foo: ["other"],
+			bar: ["defaults"],
+			nested: {
+				fizz: true,
+			}
+		}
+	`
+
+	result := GroupFixturePreparers(
+		prepareForDefaultsTest,
+		FixtureWithRootAndroidBp(bp),
+	).RunTest(t)
+
+	defaults := result.Module("defaults", "").(DefaultsModule)
+	AssertDeepEquals(t, "defaults protected properties", []string{"other.buzz", "bar", "foo", "nested.fizz"},
+		defaults.protectedProperties())
+}
+
+func TestProtectedProperties_DetectedOverride(t *testing.T) {
+	bp := `
+		defaults {
+			name: "defaults",
+			protected_properties: ["foo", "nested.fizz"],
+			foo: ["defaults"],
+			nested: {
+				fizz: true,
+			},
+		}
+
+		test {
+			name: "foo",
+			defaults: ["defaults"],
+			foo: ["module"],
+			nested: {
+				fizz: false,
+			},
+		}
+	`
+
+	GroupFixturePreparers(
+		prepareForDefaultsTest,
+		FixtureWithRootAndroidBp(bp),
+	).ExtendWithErrorHandler(FixtureExpectsAllErrorsToMatchAPattern(
+		[]string{
+			`\Qmodule "foo": attempts to append ["module"] to protected property "foo"'s value of ["defaults"] defined in module "defaults"\E`,
+			`\Qmodule "foo": attempts to override protected property "nested.fizz" defined in module "defaults" with a different value (override true with false) so removing the property may necessitate other changes.\E`,
+		})).RunTest(t)
+}
+
+func TestProtectedProperties_DefaultsConflict(t *testing.T) {
+	bp := `
+		defaults {
+			name: "defaults1",
+			protected_properties: ["other.buzz"],
+			other: {
+				buzz: "value",
+			},
+		}
+
+		defaults {
+			name: "defaults2",
+			protected_properties: ["other.buzz"],
+			other: {
+				buzz: "another",
+			},
+		}
+
+		test {
+			name: "foo",
+			defaults: ["defaults1", "defaults2"],
+		}
+	`
+
+	GroupFixturePreparers(
+		prepareForDefaultsTest,
+		FixtureWithRootAndroidBp(bp),
+	).ExtendWithErrorHandler(FixtureExpectsAtLeastOneErrorMatchingPattern(
+		`\Qmodule "foo": has conflicting default values for protected property "other.buzz":
+    defaults module "defaults1" provides value "value"
+    defaults module "defaults2" provides value "another"\E`,
+	)).RunTest(t)
+}
diff --git a/android/sdk.go b/android/sdk.go
index 1967a32..20ed794 100644
--- a/android/sdk.go
+++ b/android/sdk.go
@@ -974,3 +974,10 @@
 }
 
 var ExportedComponentsInfoProvider = blueprint.NewProvider(ExportedComponentsInfo{})
+
+// AdditionalSdkInfo contains additional properties to add to the generated SDK info file.
+type AdditionalSdkInfo struct {
+	Properties map[string]interface{}
+}
+
+var AdditionalSdkInfoProvider = blueprint.NewProvider(AdditionalSdkInfo{})
diff --git a/apex/Android.bp b/apex/Android.bp
index 41224ec..c4e6456 100644
--- a/apex/Android.bp
+++ b/apex/Android.bp
@@ -24,6 +24,7 @@
         "apex.go",
         "apex_singleton.go",
         "builder.go",
+        "constants.go",
         "deapexer.go",
         "key.go",
         "prebuilt.go",
diff --git a/apex/builder.go b/apex/builder.go
index a21fcb8..e3c4476 100644
--- a/apex/builder.go
+++ b/apex/builder.go
@@ -82,6 +82,11 @@
 		Description: "prepare ${out}",
 	}, "provideNativeLibs", "requireNativeLibs", "opt")
 
+	stripCommentsApexManifestRule = pctx.StaticRule("stripCommentsApexManifestRule", blueprint.RuleParams{
+		Command:     `sed '/^\s*\/\//d' $in > $out`,
+		Description: "strip lines starting with // ${in}=>${out}",
+	})
+
 	stripApexManifestRule = pctx.StaticRule("stripApexManifestRule", blueprint.RuleParams{
 		Command:     `rm -f $out && ${conv_apex_manifest} strip $in -o $out`,
 		CommandDeps: []string{"${conv_apex_manifest}"},
@@ -107,6 +112,7 @@
 			`--canned_fs_config ${canned_fs_config} ` +
 			`--include_build_info ` +
 			`--payload_type image ` +
+			`--apex_version ${apex_version} ` +
 			`--key ${key} ${opt_flags} ${image_dir} ${out} `,
 		CommandDeps: []string{"${apexer}", "${avbtool}", "${e2fsdroid}", "${merge_zips}",
 			"${mke2fs}", "${resize2fs}", "${sefcontext_compile}", "${make_f2fs}", "${sload_f2fs}", "${make_erofs}",
@@ -114,7 +120,7 @@
 		Rspfile:        "${out}.copy_commands",
 		RspfileContent: "${copy_commands}",
 		Description:    "APEX ${image_dir} => ${out}",
-	}, "tool_path", "image_dir", "copy_commands", "file_contexts", "canned_fs_config", "key", "opt_flags", "manifest", "payload_fs_type")
+	}, "tool_path", "image_dir", "copy_commands", "file_contexts", "canned_fs_config", "key", "opt_flags", "manifest", "payload_fs_type", "apex_version")
 
 	zipApexRule = pctx.StaticRule("zipApexRule", blueprint.RuleParams{
 		Command: `rm -rf ${image_dir} && mkdir -p ${image_dir} && ` +
@@ -122,12 +128,13 @@
 			`APEXER_TOOL_PATH=${tool_path} ` +
 			`${apexer} --force --manifest ${manifest} ` +
 			`--payload_type zip ` +
+			`--apex_version ${apex_version} ` +
 			`${image_dir} ${out} `,
 		CommandDeps:    []string{"${apexer}", "${merge_zips}", "${soong_zip}", "${zipalign}", "${aapt2}"},
 		Rspfile:        "${out}.copy_commands",
 		RspfileContent: "${copy_commands}",
 		Description:    "ZipAPEX ${image_dir} => ${out}",
-	}, "tool_path", "image_dir", "copy_commands", "manifest")
+	}, "tool_path", "image_dir", "copy_commands", "manifest", "apex_version")
 
 	apexProtoConvertRule = pctx.AndroidStaticRule("apexProtoConvertRule",
 		blueprint.RuleParams{
@@ -205,10 +212,17 @@
 		optCommands = append(optCommands, "-a jniLibs "+strings.Join(jniLibs, " "))
 	}
 
+	manifestJsonCommentsStripped := android.PathForModuleOut(ctx, "apex_manifest_comments_stripped.json")
+	ctx.Build(pctx, android.BuildParams{
+		Rule:   stripCommentsApexManifestRule,
+		Input:  src,
+		Output: manifestJsonCommentsStripped,
+	})
+
 	manifestJsonFullOut := android.PathForModuleOut(ctx, "apex_manifest_full.json")
 	ctx.Build(pctx, android.BuildParams{
 		Rule:   apexManifestRule,
-		Input:  src,
+		Input:  manifestJsonCommentsStripped,
 		Output: manifestJsonFullOut,
 		Args: map[string]string{
 			"provideNativeLibs": strings.Join(provideNativeLibs, " "),
@@ -670,6 +684,7 @@
 				"file_contexts":    fileContexts.String(),
 				"canned_fs_config": cannedFsConfig.String(),
 				"key":              a.privateKeyFile.String(),
+				"apex_version":     defaultManifestVersion,
 				"opt_flags":        strings.Join(optFlags, " "),
 			},
 		})
@@ -766,6 +781,7 @@
 				"image_dir":     imageDir.String(),
 				"copy_commands": strings.Join(copyCommands, " && "),
 				"manifest":      a.manifestPbOut.String(),
+				"apex_version":  defaultManifestVersion,
 			},
 		})
 	}
diff --git a/apex/constants.go b/apex/constants.go
new file mode 100644
index 0000000..c68edb7
--- /dev/null
+++ b/apex/constants.go
@@ -0,0 +1,36 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// 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 apex
+
+// This file contains branch specific constants. They are stored in a separate
+// file to minimise the potential of merge conflicts between branches when
+// the code from the package is changed.
+
+// The default manifest version for all the modules on this branch.
+// This version code will be used only if there is no version field in the
+// module's apex_manifest.json. Release branches have their version injected
+// into apex_manifest.json by the tooling and will not use the version set
+// here. Developers can also set the version field locally in the
+// apex_manifest.json to build a module with a specific version.
+//
+// The value follows the schema from go/mainline-version-codes, and is chosen
+// based on the branch such that the builds from testing and development
+// branches will have a version higher than the prebuilts.
+// Versions per branch:
+// * x-dev           - xx0090000 (where xx is the branch SDK level)
+// * AOSP            - xx9990000
+// * x-mainline-prod - xx9990000
+// * master          - 990090000
+const defaultManifestVersion = "339990000"
diff --git a/cc/cc_test.go b/cc/cc_test.go
index 09cc352..893c52e 100644
--- a/cc/cc_test.go
+++ b/cc/cc_test.go
@@ -4076,7 +4076,7 @@
 		{
 			name:     "assemble",
 			src:      "foo.s",
-			expected: combineSlices(baseExpectedFlags, []string{"-D__ASSEMBLY__"}, expectedIncludes, lastIncludes),
+			expected: combineSlices(baseExpectedFlags, []string{"-D__ASSEMBLY__", "-fdebug-default-version=4"}, expectedIncludes, lastIncludes),
 		},
 	}
 
diff --git a/cc/compiler.go b/cc/compiler.go
index eb5458f..383eed0 100644
--- a/cc/compiler.go
+++ b/cc/compiler.go
@@ -491,6 +491,10 @@
 
 	flags.Global.AsFlags = append(flags.Global.AsFlags, "-D__ASSEMBLY__")
 
+	// TODO(b/235105792): override global -fdebug-default-version=5, it is causing $TMPDIR to
+	// end up in the dwarf data for crtend_so.S.
+	flags.Global.AsFlags = append(flags.Global.AsFlags, "-fdebug-default-version=4")
+
 	flags.Global.CppFlags = append(flags.Global.CppFlags, tc.Cppflags())
 
 	flags.Global.YasmFlags = append(flags.Global.YasmFlags, tc.YasmFlags())
diff --git a/cmd/soong_build/main.go b/cmd/soong_build/main.go
index 4b3161b..3f8105c 100644
--- a/cmd/soong_build/main.go
+++ b/cmd/soong_build/main.go
@@ -183,8 +183,7 @@
 	touch(shared.JoinPath(topDir, queryviewMarker))
 }
 
-func writeMetrics(configuration android.Config, eventHandler metrics.EventHandler) {
-	metricsDir := configuration.Getenv("LOG_DIR")
+func writeMetrics(configuration android.Config, eventHandler metrics.EventHandler, metricsDir string) {
 	if len(metricsDir) < 1 {
 		fmt.Fprintf(os.Stderr, "\nMissing required env var for generating soong metrics: LOG_DIR\n")
 		os.Exit(1)
@@ -238,7 +237,7 @@
 // doChosenActivity runs Soong for a specific activity, like bp2build, queryview
 // or the actual Soong build for the build.ninja file. Returns the top level
 // output file of the specific activity.
-func doChosenActivity(configuration android.Config, extraNinjaDeps []string) string {
+func doChosenActivity(configuration android.Config, extraNinjaDeps []string, logDir string) string {
 	mixedModeBuild := configuration.BazelContext.BazelEnabled()
 	generateBazelWorkspace := bp2buildMarker != ""
 	generateQueryView := bazelQueryViewDir != ""
@@ -302,7 +301,7 @@
 		}
 	}
 
-	writeMetrics(configuration, *ctx.EventHandler)
+	writeMetrics(configuration, *ctx.EventHandler, logDir)
 	return cmdlineArgs.OutFile
 }
 
@@ -358,7 +357,11 @@
 		extraNinjaDeps = append(extraNinjaDeps, filepath.Join(configuration.SoongOutDir(), "always_rerun_for_delve"))
 	}
 
-	finalOutputFile := doChosenActivity(configuration, extraNinjaDeps)
+	// Bypass configuration.Getenv, as LOG_DIR does not need to be dependency tracked. By definition, it will
+	// change between every CI build, so tracking it would require re-running Soong for every build.
+	logDir := availableEnv["LOG_DIR"]
+
+	finalOutputFile := doChosenActivity(configuration, extraNinjaDeps, logDir)
 
 	writeUsedEnvironmentFile(configuration, finalOutputFile)
 }
diff --git a/java/base.go b/java/base.go
index 7aa2814..717c727 100644
--- a/java/base.go
+++ b/java/base.go
@@ -1419,17 +1419,18 @@
 	j.implementationAndResourcesJar = implementationAndResourcesJar
 
 	// Enable dex compilation for the APEX variants, unless it is disabled explicitly
+	compileDex := j.dexProperties.Compile_dex
 	apexInfo := ctx.Provider(android.ApexInfoProvider).(android.ApexInfo)
 	if j.DirectlyInAnyApex() && !apexInfo.IsForPlatform() {
-		if j.dexProperties.Compile_dex == nil {
-			j.dexProperties.Compile_dex = proptools.BoolPtr(true)
+		if compileDex == nil {
+			compileDex = proptools.BoolPtr(true)
 		}
 		if j.deviceProperties.Hostdex == nil {
 			j.deviceProperties.Hostdex = proptools.BoolPtr(true)
 		}
 	}
 
-	if ctx.Device() && (Bool(j.properties.Installable) || Bool(j.dexProperties.Compile_dex)) {
+	if ctx.Device() && (Bool(j.properties.Installable) || Bool(compileDex)) {
 		if j.hasCode(ctx) {
 			if j.shouldInstrumentStatic(ctx) {
 				j.dexer.extraProguardFlagFiles = append(j.dexer.extraProguardFlagFiles,
diff --git a/java/droidstubs.go b/java/droidstubs.go
index 3b1f7c0..20ea5ff 100644
--- a/java/droidstubs.go
+++ b/java/droidstubs.go
@@ -675,87 +675,16 @@
 
 	zipSyncCleanupCmd(rule, srcJarDir)
 
-	rule.Build("metalava", "metalava merged")
-
 	if apiCheckEnabled(ctx, d.properties.Check_api.Current, "current") {
+		d.generateCheckCurrentCheckedInApiIsUpToDateBuildRules(ctx)
 
-		if len(d.Javadoc.properties.Out) > 0 {
-			ctx.PropertyErrorf("out", "out property may not be combined with check_api")
-		}
-
-		apiFile := android.PathForModuleSrc(ctx, String(d.properties.Check_api.Current.Api_file))
-		removedApiFile := android.PathForModuleSrc(ctx, String(d.properties.Check_api.Current.Removed_api_file))
-		baselineFile := android.OptionalPathForModuleSrc(ctx, d.properties.Check_api.Current.Baseline_file)
-
-		if baselineFile.Valid() {
-			ctx.PropertyErrorf("baseline_file", "current API check can't have a baseline file. (module %s)", ctx.ModuleName())
-		}
-
-		d.checkCurrentApiTimestamp = android.PathForModuleOut(ctx, "metalava", "check_current_api.timestamp")
-
-		rule := android.NewRuleBuilder(pctx, ctx)
-
-		// Diff command line.
-		// -F matches the closest "opening" line, such as "package android {"
-		// and "  public class Intent {".
-		diff := `diff -u -F '{ *$'`
-
-		rule.Command().Text("( true")
-		rule.Command().
-			Text(diff).
-			Input(apiFile).Input(d.apiFile)
-
-		rule.Command().
-			Text(diff).
-			Input(removedApiFile).Input(d.removedApiFile)
-
-		msg := fmt.Sprintf(`\n******************************\n`+
-			`You have tried to change the API from what has been previously approved.\n\n`+
-			`To make these errors go away, you have two choices:\n`+
-			`   1. You can add '@hide' javadoc comments (and remove @SystemApi/@TestApi/etc)\n`+
-			`      to the new methods, etc. shown in the above diff.\n\n`+
-			`   2. You can update current.txt and/or removed.txt by executing the following command:\n`+
-			`         m %s-update-current-api\n\n`+
-			`      To submit the revised current.txt to the main Android repository,\n`+
-			`      you will need approval.\n`+
-			`******************************\n`, ctx.ModuleName())
-
-		rule.Command().
-			Text("touch").Output(d.checkCurrentApiTimestamp).
-			Text(") || (").
-			Text("echo").Flag("-e").Flag(`"` + msg + `"`).
-			Text("; exit 38").
-			Text(")")
-
-		rule.Build("metalavaCurrentApiCheck", "check current API")
-
-		d.updateCurrentApiTimestamp = android.PathForModuleOut(ctx, "metalava", "update_current_api.timestamp")
-
-		// update API rule
-		rule = android.NewRuleBuilder(pctx, ctx)
-
-		rule.Command().Text("( true")
-
-		rule.Command().
-			Text("cp").Flag("-f").
-			Input(d.apiFile).Flag(apiFile.String())
-
-		rule.Command().
-			Text("cp").Flag("-f").
-			Input(d.removedApiFile).Flag(removedApiFile.String())
-
-		msg = "failed to update public API"
-
-		rule.Command().
-			Text("touch").Output(d.updateCurrentApiTimestamp).
-			Text(") || (").
-			Text("echo").Flag("-e").Flag(`"` + msg + `"`).
-			Text("; exit 38").
-			Text(")")
-
-		rule.Build("metalavaCurrentApiUpdate", "update current API")
+		// Make sure that whenever the API stubs are generated that the current checked in API files are
+		// checked to make sure that they are up-to-date.
+		cmd.Validation(d.checkCurrentApiTimestamp)
 	}
 
+	rule.Build("metalava", "metalava merged")
+
 	if String(d.properties.Check_nullability_warnings) != "" {
 		if d.nullabilityWarningsFile == nil {
 			ctx.PropertyErrorf("check_nullability_warnings",
@@ -792,6 +721,84 @@
 	}
 }
 
+func (d *Droidstubs) generateCheckCurrentCheckedInApiIsUpToDateBuildRules(ctx android.ModuleContext) {
+	if len(d.Javadoc.properties.Out) > 0 {
+		ctx.PropertyErrorf("out", "out property may not be combined with check_api")
+	}
+
+	apiFile := android.PathForModuleSrc(ctx, String(d.properties.Check_api.Current.Api_file))
+	removedApiFile := android.PathForModuleSrc(ctx, String(d.properties.Check_api.Current.Removed_api_file))
+	baselineFile := android.OptionalPathForModuleSrc(ctx, d.properties.Check_api.Current.Baseline_file)
+
+	if baselineFile.Valid() {
+		ctx.PropertyErrorf("baseline_file", "current API check can't have a baseline file. (module %s)", ctx.ModuleName())
+	}
+
+	d.checkCurrentApiTimestamp = android.PathForModuleOut(ctx, "metalava", "check_current_api.timestamp")
+
+	rule := android.NewRuleBuilder(pctx, ctx)
+
+	// Diff command line.
+	// -F matches the closest "opening" line, such as "package android {"
+	// and "  public class Intent {".
+	diff := `diff -u -F '{ *$'`
+
+	rule.Command().Text("( true")
+	rule.Command().
+		Text(diff).
+		Input(apiFile).Input(d.apiFile)
+
+	rule.Command().
+		Text(diff).
+		Input(removedApiFile).Input(d.removedApiFile)
+
+	msg := fmt.Sprintf(`\n******************************\n`+
+		`You have tried to change the API from what has been previously approved.\n\n`+
+		`To make these errors go away, you have two choices:\n`+
+		`   1. You can add '@hide' javadoc comments (and remove @SystemApi/@TestApi/etc)\n`+
+		`      to the new methods, etc. shown in the above diff.\n\n`+
+		`   2. You can update current.txt and/or removed.txt by executing the following command:\n`+
+		`         m %s-update-current-api\n\n`+
+		`      To submit the revised current.txt to the main Android repository,\n`+
+		`      you will need approval.\n`+
+		`******************************\n`, ctx.ModuleName())
+
+	rule.Command().
+		Text("touch").Output(d.checkCurrentApiTimestamp).
+		Text(") || (").
+		Text("echo").Flag("-e").Flag(`"` + msg + `"`).
+		Text("; exit 38").
+		Text(")")
+
+	rule.Build("metalavaCurrentApiCheck", "check current API")
+
+	d.updateCurrentApiTimestamp = android.PathForModuleOut(ctx, "metalava", "update_current_api.timestamp")
+
+	// update API rule
+	rule = android.NewRuleBuilder(pctx, ctx)
+
+	rule.Command().Text("( true")
+
+	rule.Command().
+		Text("cp").Flag("-f").
+		Input(d.apiFile).Flag(apiFile.String())
+
+	rule.Command().
+		Text("cp").Flag("-f").
+		Input(d.removedApiFile).Flag(removedApiFile.String())
+
+	msg = "failed to update public API"
+
+	rule.Command().
+		Text("touch").Output(d.updateCurrentApiTimestamp).
+		Text(") || (").
+		Text("echo").Flag("-e").Flag(`"` + msg + `"`).
+		Text("; exit 38").
+		Text(")")
+
+	rule.Build("metalavaCurrentApiUpdate", "update current API")
+}
+
 func StubsDefaultsFactory() android.Module {
 	module := &DocDefaults{}
 
diff --git a/java/prebuilt_apis.go b/java/prebuilt_apis.go
index 44650a6..9449707 100644
--- a/java/prebuilt_apis.go
+++ b/java/prebuilt_apis.go
@@ -212,6 +212,10 @@
 	mctx.CreateModule(systemModulesImportFactory, &props)
 }
 
+func PrebuiltApiModuleName(module, scope, version string) string {
+	return module + ".api." + scope + "." + version
+}
+
 func prebuiltApiFiles(mctx android.LoadHookContext, p *prebuiltApis) {
 	// <apiver>/<scope>/api/<module>.txt
 	apiLevelFiles := globApiDirs(mctx, p, "api/*.txt")
@@ -220,12 +224,9 @@
 	}
 
 	// Create modules for all (<module>, <scope, <version>) triplets,
-	apiModuleName := func(module, scope, version string) string {
-		return module + ".api." + scope + "." + version
-	}
 	for _, f := range apiLevelFiles {
 		module, version, scope := parseFinalizedPrebuiltPath(mctx, f)
-		createApiModule(mctx, apiModuleName(module, scope, strconv.Itoa(version)), f)
+		createApiModule(mctx, PrebuiltApiModuleName(module, scope, strconv.Itoa(version)), f)
 	}
 
 	// Figure out the latest version of each module/scope
@@ -266,7 +267,7 @@
 	// Sort the keys in order to make build.ninja stable
 	for _, k := range android.SortedStringKeys(latest) {
 		info := latest[k]
-		name := apiModuleName(info.module, info.scope, "latest")
+		name := PrebuiltApiModuleName(info.module, info.scope, "latest")
 		createApiModule(mctx, name, info.path)
 	}
 
@@ -278,7 +279,7 @@
 			filename, _, scope := parsePrebuiltPath(mctx, f)
 			referencedModule := strings.TrimSuffix(filename, "-incompatibilities")
 
-			createApiModule(mctx, apiModuleName(referencedModule+"-incompatibilities", scope, "latest"), f)
+			createApiModule(mctx, PrebuiltApiModuleName(referencedModule+"-incompatibilities", scope, "latest"), f)
 
 			incompatibilities[referencedModule+"."+scope] = true
 		}
@@ -286,7 +287,7 @@
 	// Create empty incompatibilities files for remaining modules
 	for _, k := range android.SortedStringKeys(latest) {
 		if _, ok := incompatibilities[k]; !ok {
-			createEmptyFile(mctx, apiModuleName(latest[k].module+"-incompatibilities", latest[k].scope, "latest"))
+			createEmptyFile(mctx, PrebuiltApiModuleName(latest[k].module+"-incompatibilities", latest[k].scope, "latest"))
 		}
 	}
 }
diff --git a/java/sdk_library.go b/java/sdk_library.go
index 47ffc6a..591e90f 100644
--- a/java/sdk_library.go
+++ b/java/sdk_library.go
@@ -97,6 +97,13 @@
 	// The tag to use to depend on the stubs source and API module.
 	stubsSourceAndApiTag scopeDependencyTag
 
+	// The tag to use to depend on the module that provides the latest version of the API .txt file.
+	latestApiModuleTag scopeDependencyTag
+
+	// The tag to use to depend on the module that provides the latest version of the API removed.txt
+	// file.
+	latestRemovedApiModuleTag scopeDependencyTag
+
 	// The scope specific prefix to add to the api file base of "current.txt" or "removed.txt".
 	apiFilePrefix string
 
@@ -158,6 +165,16 @@
 		apiScope:         scope,
 		depInfoExtractor: (*scopePaths).extractStubsSourceAndApiInfoFromApiStubsProvider,
 	}
+	scope.latestApiModuleTag = scopeDependencyTag{
+		name:             name + "-latest-api",
+		apiScope:         scope,
+		depInfoExtractor: (*scopePaths).extractLatestApiPath,
+	}
+	scope.latestRemovedApiModuleTag = scopeDependencyTag{
+		name:             name + "-latest-removed-api",
+		apiScope:         scope,
+		depInfoExtractor: (*scopePaths).extractLatestRemovedApiPath,
+	}
 
 	// To get the args needed to generate the stubs source append all the args from
 	// this scope and all the scopes it extends as each set of args adds additional
@@ -203,6 +220,24 @@
 	return scope.name
 }
 
+// snapshotRelativeDir returns the snapshot directory into which the files related to scopes will
+// be stored.
+func (scope *apiScope) snapshotRelativeDir() string {
+	return filepath.Join("sdk_library", scope.name)
+}
+
+// snapshotRelativeCurrentApiTxtPath returns the snapshot path to the API .txt file for the named
+// library.
+func (scope *apiScope) snapshotRelativeCurrentApiTxtPath(name string) string {
+	return filepath.Join(scope.snapshotRelativeDir(), name+".txt")
+}
+
+// snapshotRelativeRemovedApiTxtPath returns the snapshot path to the removed API .txt file for the
+// named library.
+func (scope *apiScope) snapshotRelativeRemovedApiTxtPath(name string) string {
+	return filepath.Join(scope.snapshotRelativeDir(), name+"-removed.txt")
+}
+
 type apiScopes []*apiScope
 
 func (scopes apiScopes) Strings(accessor func(*apiScope) string) []string {
@@ -539,6 +574,12 @@
 
 	// Extracted annotations.
 	annotationsZip android.OptionalPath
+
+	// The path to the latest API file.
+	latestApiPath android.OptionalPath
+
+	// The path to the latest removed API file.
+	latestRemovedApiPath android.OptionalPath
 }
 
 func (paths *scopePaths) extractStubsLibraryInfoFromDependency(ctx android.ModuleContext, dep android.Module) error {
@@ -602,6 +643,31 @@
 	})
 }
 
+func extractSingleOptionalOutputPath(dep android.Module) (android.OptionalPath, error) {
+	var paths android.Paths
+	if sourceFileProducer, ok := dep.(android.SourceFileProducer); ok {
+		paths = sourceFileProducer.Srcs()
+	} else {
+		return android.OptionalPath{}, fmt.Errorf("module %q does not produce source files", dep)
+	}
+	if len(paths) != 1 {
+		return android.OptionalPath{}, fmt.Errorf("expected one path from %q, got %q", dep, paths)
+	}
+	return android.OptionalPathForPath(paths[0]), nil
+}
+
+func (paths *scopePaths) extractLatestApiPath(ctx android.ModuleContext, dep android.Module) error {
+	outputPath, err := extractSingleOptionalOutputPath(dep)
+	paths.latestApiPath = outputPath
+	return err
+}
+
+func (paths *scopePaths) extractLatestRemovedApiPath(ctx android.ModuleContext, dep android.Module) error {
+	outputPath, err := extractSingleOptionalOutputPath(dep)
+	paths.latestRemovedApiPath = outputPath
+	return err
+}
+
 type commonToSdkLibraryAndImportProperties struct {
 	// The naming scheme to use for the components that this module creates.
 	//
@@ -1174,6 +1240,16 @@
 
 		// Add a dependency on the stubs source in order to access both stubs source and api information.
 		ctx.AddVariationDependencies(nil, apiScope.stubsSourceAndApiTag, module.stubsSourceModuleName(apiScope))
+
+		if module.compareAgainstLatestApi(apiScope) {
+			// Add dependencies on the latest finalized version of the API .txt file.
+			latestApiModuleName := module.latestApiModuleName(apiScope)
+			ctx.AddDependency(module, apiScope.latestApiModuleTag, latestApiModuleName)
+
+			// Add dependencies on the latest finalized version of the remove API .txt file.
+			latestRemovedApiModuleName := module.latestRemovedApiModuleName(apiScope)
+			ctx.AddDependency(module, apiScope.latestRemovedApiModuleTag, latestRemovedApiModuleName)
+		}
 	}
 
 	if module.requiresRuntimeImplementationLibrary() {
@@ -1194,13 +1270,13 @@
 		if apiScope.unstable {
 			continue
 		}
-		if m := android.SrcIsModule(module.latestApiFilegroupName(apiScope)); !ctx.OtherModuleExists(m) {
+		if m := module.latestApiModuleName(apiScope); !ctx.OtherModuleExists(m) {
 			missingApiModules = append(missingApiModules, m)
 		}
-		if m := android.SrcIsModule(module.latestRemovedApiFilegroupName(apiScope)); !ctx.OtherModuleExists(m) {
+		if m := module.latestRemovedApiModuleName(apiScope); !ctx.OtherModuleExists(m) {
 			missingApiModules = append(missingApiModules, m)
 		}
-		if m := android.SrcIsModule(module.latestIncompatibilitiesFilegroupName(apiScope)); !ctx.OtherModuleExists(m) {
+		if m := module.latestIncompatibilitiesModuleName(apiScope); !ctx.OtherModuleExists(m) {
 			missingApiModules = append(missingApiModules, m)
 		}
 	}
@@ -1274,6 +1350,26 @@
 	// Make the set of components exported by this module available for use elsewhere.
 	exportedComponentInfo := android.ExportedComponentsInfo{Components: android.SortedStringKeys(exportedComponents)}
 	ctx.SetProvider(android.ExportedComponentsInfoProvider, exportedComponentInfo)
+
+	// Provide additional information for inclusion in an sdk's generated .info file.
+	additionalSdkInfo := map[string]interface{}{}
+	additionalSdkInfo["dist_stem"] = module.distStem()
+	baseModuleName := module.BaseModuleName()
+	scopes := map[string]interface{}{}
+	additionalSdkInfo["scopes"] = scopes
+	for scope, scopePaths := range module.scopePaths {
+		scopeInfo := map[string]interface{}{}
+		scopes[scope.name] = scopeInfo
+		scopeInfo["current_api"] = scope.snapshotRelativeCurrentApiTxtPath(baseModuleName)
+		scopeInfo["removed_api"] = scope.snapshotRelativeRemovedApiTxtPath(baseModuleName)
+		if p := scopePaths.latestApiPath; p.Valid() {
+			scopeInfo["latest_api"] = p.Path().String()
+		}
+		if p := scopePaths.latestRemovedApiPath; p.Valid() {
+			scopeInfo["latest_removed_api"] = p.Path().String()
+		}
+	}
+	ctx.SetProvider(android.AdditionalSdkInfoProvider, android.AdditionalSdkInfo{additionalSdkInfo})
 }
 
 func (module *SdkLibrary) AndroidMkEntries() []android.AndroidMkEntries {
@@ -1319,16 +1415,32 @@
 	return proptools.StringDefault(module.sdkLibraryProperties.Dist_group, "unknown")
 }
 
+func latestPrebuiltApiModuleName(name string, apiScope *apiScope) string {
+	return PrebuiltApiModuleName(name, apiScope.name, "latest")
+}
+
 func (module *SdkLibrary) latestApiFilegroupName(apiScope *apiScope) string {
-	return ":" + module.distStem() + ".api." + apiScope.name + ".latest"
+	return ":" + module.latestApiModuleName(apiScope)
+}
+
+func (module *SdkLibrary) latestApiModuleName(apiScope *apiScope) string {
+	return latestPrebuiltApiModuleName(module.distStem(), apiScope)
 }
 
 func (module *SdkLibrary) latestRemovedApiFilegroupName(apiScope *apiScope) string {
-	return ":" + module.distStem() + "-removed.api." + apiScope.name + ".latest"
+	return ":" + module.latestRemovedApiModuleName(apiScope)
+}
+
+func (module *SdkLibrary) latestRemovedApiModuleName(apiScope *apiScope) string {
+	return latestPrebuiltApiModuleName(module.distStem()+"-removed", apiScope)
 }
 
 func (module *SdkLibrary) latestIncompatibilitiesFilegroupName(apiScope *apiScope) string {
-	return ":" + module.distStem() + "-incompatibilities.api." + apiScope.name + ".latest"
+	return ":" + module.latestIncompatibilitiesModuleName(apiScope)
+}
+
+func (module *SdkLibrary) latestIncompatibilitiesModuleName(apiScope *apiScope) string {
+	return latestPrebuiltApiModuleName(module.distStem()+"-incompatibilities", apiScope)
 }
 
 func childModuleVisibility(childVisibility []string) []string {
@@ -1557,7 +1669,7 @@
 	props.Check_api.Current.Api_file = proptools.StringPtr(currentApiFileName)
 	props.Check_api.Current.Removed_api_file = proptools.StringPtr(removedApiFileName)
 
-	if !(apiScope.unstable || module.sdkLibraryProperties.Unsafe_ignore_missing_latest_api) {
+	if module.compareAgainstLatestApi(apiScope) {
 		// check against the latest released API
 		latestApiFilegroupName := proptools.StringPtr(module.latestApiFilegroupName(apiScope))
 		props.Previous_api = latestApiFilegroupName
@@ -1609,6 +1721,10 @@
 	mctx.CreateModule(DroidstubsFactory, &props)
 }
 
+func (module *SdkLibrary) compareAgainstLatestApi(apiScope *apiScope) bool {
+	return !(apiScope.unstable || module.sdkLibraryProperties.Unsafe_ignore_missing_latest_api)
+}
+
 // Implements android.ApexModule
 func (module *SdkLibrary) DepIsInSameApex(mctx android.BaseModuleContext, dep android.Module) bool {
 	depTag := mctx.OtherModuleDependencyTag(dep)
@@ -2906,7 +3022,7 @@
 		if properties, ok := s.Scopes[apiScope]; ok {
 			scopeSet := propertySet.AddPropertySet(apiScope.propertyName)
 
-			scopeDir := filepath.Join("sdk_library", s.OsPrefix(), apiScope.name)
+			scopeDir := apiScope.snapshotRelativeDir()
 
 			var jars []string
 			for _, p := range properties.Jars {
@@ -2930,13 +3046,13 @@
 			}
 
 			if properties.CurrentApiFile != nil {
-				currentApiSnapshotPath := filepath.Join(scopeDir, ctx.Name()+".txt")
+				currentApiSnapshotPath := apiScope.snapshotRelativeCurrentApiTxtPath(ctx.Name())
 				ctx.SnapshotBuilder().CopyToSnapshot(properties.CurrentApiFile, currentApiSnapshotPath)
 				scopeSet.AddProperty("current_api", currentApiSnapshotPath)
 			}
 
 			if properties.RemovedApiFile != nil {
-				removedApiSnapshotPath := filepath.Join(scopeDir, ctx.Name()+"-removed.txt")
+				removedApiSnapshotPath := apiScope.snapshotRelativeRemovedApiTxtPath(ctx.Name())
 				ctx.SnapshotBuilder().CopyToSnapshot(properties.RemovedApiFile, removedApiSnapshotPath)
 				scopeSet.AddProperty("removed_api", removedApiSnapshotPath)
 			}
diff --git a/java/sdk_library_test.go b/java/sdk_library_test.go
index 3500c84..805bc22 100644
--- a/java/sdk_library_test.go
+++ b/java/sdk_library_test.go
@@ -126,6 +126,10 @@
 
 	exportedComponentsInfo := result.ModuleProvider(foo.Module(), android.ExportedComponentsInfoProvider).(android.ExportedComponentsInfo)
 	expectedFooExportedComponents := []string{
+		"foo-removed.api.public.latest",
+		"foo-removed.api.system.latest",
+		"foo.api.public.latest",
+		"foo.api.system.latest",
 		"foo.stubs",
 		"foo.stubs.source",
 		"foo.stubs.source.system",
@@ -529,6 +533,8 @@
 
 	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
 		`dex2oatd`,
+		`sdklib-removed.api.public.latest`,
+		`sdklib.api.public.latest`,
 		`sdklib.impl`,
 		`sdklib.stubs`,
 		`sdklib.stubs.source`,
@@ -851,6 +857,8 @@
 	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
 		`dex2oatd`,
 		`prebuilt_sdklib`,
+		`sdklib-removed.api.public.latest`,
+		`sdklib.api.public.latest`,
 		`sdklib.impl`,
 		`sdklib.stubs`,
 		`sdklib.stubs.source`,
@@ -894,6 +902,8 @@
 
 	CheckModuleDependencies(t, result.TestContext, "sdklib", "android_common", []string{
 		`prebuilt_sdklib`,
+		`sdklib-removed.api.public.latest`,
+		`sdklib.api.public.latest`,
 		`sdklib.impl`,
 		`sdklib.stubs`,
 		`sdklib.stubs.source`,
diff --git a/sdk/java_sdk_test.go b/sdk/java_sdk_test.go
index a99fa1f..f33aa26 100644
--- a/sdk/java_sdk_test.go
+++ b/sdk/java_sdk_test.go
@@ -651,7 +651,19 @@
 }
 
 func TestSnapshotWithJavaSystemModules(t *testing.T) {
-	result := android.GroupFixturePreparers(prepareForSdkTestWithJavaSdkLibrary).RunTestWithBp(t, `
+	result := android.GroupFixturePreparers(
+		prepareForSdkTestWithJava,
+		java.PrepareForTestWithJavaDefaultModules,
+		java.PrepareForTestWithJavaSdkLibraryFiles,
+		java.FixtureWithPrebuiltApisAndExtensions(map[string][]string{
+			"31":      {"myjavalib"},
+			"32":      {"myjavalib"},
+			"current": {"myjavalib"},
+		}, map[string][]string{
+			"1": {"myjavalib"},
+			"2": {"myjavalib"},
+		}),
+	).RunTestWithBp(t, `
 		sdk {
 			name: "mysdk",
 			java_header_libs: ["exported-system-module"],
@@ -796,6 +808,53 @@
 .intermediates/myjavalib.stubs.source/android_common/metalava/myjavalib.stubs.source_api.txt -> sdk_library/public/myjavalib.txt
 .intermediates/myjavalib.stubs.source/android_common/metalava/myjavalib.stubs.source_removed.txt -> sdk_library/public/myjavalib-removed.txt
 `),
+		checkInfoContents(result.Config, `
+[
+  {
+    "@type": "sdk",
+    "@name": "mysdk",
+    "java_header_libs": [
+      "exported-system-module",
+      "system-module"
+    ],
+    "java_sdk_libs": [
+      "myjavalib"
+    ],
+    "java_system_modules": [
+      "my-system-modules"
+    ]
+  },
+  {
+    "@type": "java_library",
+    "@name": "exported-system-module"
+  },
+  {
+    "@type": "java_system_modules",
+    "@name": "my-system-modules",
+    "@deps": [
+      "exported-system-module",
+      "system-module"
+    ]
+  },
+  {
+    "@type": "java_sdk_library",
+    "@name": "myjavalib",
+    "dist_stem": "myjavalib",
+    "scopes": {
+      "public": {
+        "current_api": "sdk_library/public/myjavalib.txt",
+        "latest_api": "out/soong/.intermediates/prebuilts/sdk/myjavalib.api.public.latest/gen/myjavalib.api.public.latest",
+        "latest_removed_api": "out/soong/.intermediates/prebuilts/sdk/myjavalib-removed.api.public.latest/gen/myjavalib-removed.api.public.latest",
+        "removed_api": "sdk_library/public/myjavalib-removed.txt"
+      }
+    }
+  },
+  {
+    "@type": "java_library",
+    "@name": "system-module"
+  }
+]
+`),
 	)
 }
 
diff --git a/sdk/sdk.go b/sdk/sdk.go
index c8c7b79..b37eaad 100644
--- a/sdk/sdk.go
+++ b/sdk/sdk.go
@@ -75,6 +75,8 @@
 
 	snapshotFile android.OptionalPath
 
+	infoFile android.OptionalPath
+
 	// The builder, preserved for testing.
 	builderForTests *snapshotBuilder
 }
@@ -191,27 +193,32 @@
 		}
 
 		// Generate the snapshot from the member info.
-		p := s.buildSnapshot(ctx, sdkVariants)
-		zip := ctx.InstallFile(android.PathForMainlineSdksInstall(ctx), p.Base(), p)
-		s.snapshotFile = android.OptionalPathForPath(zip)
+		s.buildSnapshot(ctx, sdkVariants)
 	}
 }
 
 func (s *sdk) AndroidMkEntries() []android.AndroidMkEntries {
-	if !s.snapshotFile.Valid() {
+	if !s.snapshotFile.Valid() != !s.infoFile.Valid() {
+		panic("Snapshot (%q) and info file (%q) should both be set or neither should be set.")
+	} else if !s.snapshotFile.Valid() {
 		return []android.AndroidMkEntries{}
 	}
 
 	return []android.AndroidMkEntries{android.AndroidMkEntries{
 		Class:      "FAKE",
 		OutputFile: s.snapshotFile,
-		DistFiles:  android.MakeDefaultDistFiles(s.snapshotFile.Path()),
+		DistFiles:  android.MakeDefaultDistFiles(s.snapshotFile.Path(), s.infoFile.Path()),
 		Include:    "$(BUILD_PHONY_PACKAGE)",
 		ExtraFooters: []android.AndroidMkExtraFootersFunc{
 			func(w io.Writer, name, prefix, moduleDir string) {
 				// Allow the sdk to be built by simply passing its name on the command line.
 				fmt.Fprintln(w, ".PHONY:", s.Name())
 				fmt.Fprintln(w, s.Name()+":", s.snapshotFile.String())
+
+				// Allow the sdk info to be built by simply passing its name on the command line.
+				infoTarget := s.Name() + ".info"
+				fmt.Fprintln(w, ".PHONY:", infoTarget)
+				fmt.Fprintln(w, infoTarget+":", s.infoFile.String())
 			},
 		},
 	}}
diff --git a/sdk/sdk_test.go b/sdk/sdk_test.go
index 40de150..ccbeb8d 100644
--- a/sdk/sdk_test.go
+++ b/sdk/sdk_test.go
@@ -263,7 +263,10 @@
 	result := testSdkWithFs(t, sdk, nil)
 
 	CheckSnapshot(t, result, "mysdk", "",
-		checkAllOtherCopyRules(`.intermediates/mysdk/common_os/mysdk-current.zip -> mysdk-current.zip`))
+		checkAllOtherCopyRules(`
+.intermediates/mysdk/common_os/mysdk-current.info -> mysdk-current.info
+.intermediates/mysdk/common_os/mysdk-current.zip -> mysdk-current.zip
+`))
 }
 
 type EmbeddedPropertiesStruct struct {
diff --git a/sdk/testing.go b/sdk/testing.go
index 062f200..72344de 100644
--- a/sdk/testing.go
+++ b/sdk/testing.go
@@ -142,6 +142,7 @@
 		androidBpContents:            sdk.GetAndroidBpContentsForTests(),
 		androidUnversionedBpContents: sdk.GetUnversionedAndroidBpContentsForTests(),
 		androidVersionedBpContents:   sdk.GetVersionedAndroidBpContentsForTests(),
+		infoContents:                 sdk.GetInfoContentsForTests(),
 		snapshotTestCustomizations:   map[snapshotTest]*snapshotTestCustomization{},
 		targetBuildRelease:           sdk.builderForTests.targetBuildRelease,
 	}
@@ -402,6 +403,17 @@
 	}
 }
 
+// Check that the snapshot's info contents are ciorrect.
+//
+// Both the expected and actual string are both trimmed before comparing.
+func checkInfoContents(config android.Config, expected string) snapshotBuildInfoChecker {
+	return func(info *snapshotBuildInfo) {
+		info.t.Helper()
+		android.AssertTrimmedStringEquals(info.t, "info contents do not match",
+			expected, android.StringRelativeToTop(config, info.infoContents))
+	}
+}
+
 type resultChecker func(t *testing.T, result *android.TestResult)
 
 // snapshotTestPreparer registers a preparer that will be used to customize the specified
@@ -479,6 +491,9 @@
 	// The contents of the versioned Android.bp file
 	androidVersionedBpContents string
 
+	// The contents of the info file.
+	infoContents string
+
 	// The paths, relative to the snapshot root, of all files and directories copied into the
 	// snapshot.
 	snapshotContents []string
diff --git a/sdk/update.go b/sdk/update.go
index 740b23c..af2b247 100644
--- a/sdk/update.go
+++ b/sdk/update.go
@@ -15,6 +15,8 @@
 package sdk
 
 import (
+	"bytes"
+	"encoding/json"
 	"fmt"
 	"reflect"
 	"sort"
@@ -219,9 +221,19 @@
 				exportedComponentsInfo = ctx.OtherModuleProvider(child, android.ExportedComponentsInfoProvider).(android.ExportedComponentsInfo)
 			}
 
+			var container android.SdkAware
+			if parent != ctx.Module() {
+				container = parent.(android.SdkAware)
+			}
+
 			export := memberTag.ExportMember()
 			s.memberVariantDeps = append(s.memberVariantDeps, sdkMemberVariantDep{
-				s, memberType, child.(android.SdkAware), export, exportedComponentsInfo,
+				sdkVariant:             s,
+				memberType:             memberType,
+				variant:                child.(android.SdkAware),
+				container:              container,
+				export:                 export,
+				exportedComponentsInfo: exportedComponentsInfo,
 			})
 
 			// Recurse down into the member's dependencies as it may have dependencies that need to be
@@ -337,7 +349,7 @@
 
 // buildSnapshot is the main function in this source file. It creates rules to copy
 // the contents (header files, stub libraries, etc) into the zip file.
-func (s *sdk) buildSnapshot(ctx android.ModuleContext, sdkVariants []*sdk) android.OutputPath {
+func (s *sdk) buildSnapshot(ctx android.ModuleContext, sdkVariants []*sdk) {
 
 	// Aggregate all the sdkMemberVariantDep instances from all the sdk variants.
 	hasLicenses := false
@@ -396,9 +408,9 @@
 	// Unversioned modules are not required in that case because the numbered version will be a
 	// finalized version of the snapshot that is intended to be kept separate from the
 	generateUnversioned := version == soongSdkSnapshotVersionUnversioned || version == soongSdkSnapshotVersionCurrent
-	snapshotZipFileSuffix := ""
+	snapshotFileSuffix := ""
 	if generateVersioned {
-		snapshotZipFileSuffix = "-" + version
+		snapshotFileSuffix = "-" + version
 	}
 
 	currentBuildRelease := latestBuildRelease()
@@ -515,7 +527,7 @@
 	filesToZip := builder.filesToZip
 
 	// zip them all
-	zipPath := fmt.Sprintf("%s%s.zip", ctx.ModuleName(), snapshotZipFileSuffix)
+	zipPath := fmt.Sprintf("%s%s.zip", ctx.ModuleName(), snapshotFileSuffix)
 	outputZipFile := android.PathForModuleOut(ctx, zipPath).OutputPath
 	outputDesc := "Building snapshot for " + ctx.ModuleName()
 
@@ -528,7 +540,7 @@
 		zipFile = outputZipFile
 		desc = outputDesc
 	} else {
-		intermediatePath := fmt.Sprintf("%s%s.unmerged.zip", ctx.ModuleName(), snapshotZipFileSuffix)
+		intermediatePath := fmt.Sprintf("%s%s.unmerged.zip", ctx.ModuleName(), snapshotFileSuffix)
 		zipFile = android.PathForModuleOut(ctx, intermediatePath).OutputPath
 		desc = "Building intermediate snapshot for " + ctx.ModuleName()
 	}
@@ -553,7 +565,125 @@
 		})
 	}
 
-	return outputZipFile
+	modules := s.generateInfoData(ctx, memberVariantDeps)
+
+	// Output the modules information as pretty printed JSON.
+	info := newGeneratedFile(ctx, fmt.Sprintf("%s%s.info", ctx.ModuleName(), snapshotFileSuffix))
+	output, err := json.MarshalIndent(modules, "", "  ")
+	if err != nil {
+		ctx.ModuleErrorf("error generating %q: %s", info, err)
+	}
+	builder.infoContents = string(output)
+	info.generatedContents.UnindentedPrintf("%s", output)
+	info.build(pctx, ctx, nil)
+	infoPath := info.path
+	installedInfo := ctx.InstallFile(android.PathForMainlineSdksInstall(ctx), infoPath.Base(), infoPath)
+	s.infoFile = android.OptionalPathForPath(installedInfo)
+
+	// Install the zip, making sure that the info file has been installed as well.
+	installedZip := ctx.InstallFile(android.PathForMainlineSdksInstall(ctx), outputZipFile.Base(), outputZipFile, installedInfo)
+	s.snapshotFile = android.OptionalPathForPath(installedZip)
+}
+
+type moduleInfo struct {
+	// The type of the module, e.g. java_sdk_library
+	moduleType string
+	// The name of the module.
+	name string
+	// A list of additional dependencies of the module.
+	deps []string
+	// Additional member specific properties.
+	// These will be added into the generated JSON alongside the above properties.
+	memberSpecific map[string]interface{}
+}
+
+func (m *moduleInfo) MarshalJSON() ([]byte, error) {
+	buffer := bytes.Buffer{}
+
+	separator := ""
+	writeObjectPair := func(key string, value interface{}) {
+		buffer.WriteString(fmt.Sprintf("%s%q: ", separator, key))
+		b, err := json.Marshal(value)
+		if err != nil {
+			panic(err)
+		}
+		buffer.Write(b)
+		separator = ","
+	}
+
+	buffer.WriteString("{")
+	writeObjectPair("@type", m.moduleType)
+	writeObjectPair("@name", m.name)
+	if m.deps != nil {
+		writeObjectPair("@deps", m.deps)
+	}
+	for _, k := range android.SortedStringKeys(m.memberSpecific) {
+		v := m.memberSpecific[k]
+		writeObjectPair(k, v)
+	}
+	buffer.WriteString("}")
+	return buffer.Bytes(), nil
+}
+
+var _ json.Marshaler = (*moduleInfo)(nil)
+
+// generateInfoData creates a list of moduleInfo structures that will be marshalled into JSON.
+func (s *sdk) generateInfoData(ctx android.ModuleContext, memberVariantDeps []sdkMemberVariantDep) interface{} {
+	modules := []*moduleInfo{}
+	sdkInfo := moduleInfo{
+		moduleType:     "sdk",
+		name:           ctx.ModuleName(),
+		memberSpecific: map[string]interface{}{},
+	}
+	modules = append(modules, &sdkInfo)
+
+	name2Info := map[string]*moduleInfo{}
+	getModuleInfo := func(module android.Module) *moduleInfo {
+		name := module.Name()
+		info := name2Info[name]
+		if info == nil {
+			moduleType := ctx.OtherModuleType(module)
+			// Remove any suffix added when creating modules dynamically.
+			moduleType = strings.Split(moduleType, "__")[0]
+			info = &moduleInfo{
+				moduleType: moduleType,
+				name:       name,
+			}
+
+			additionalSdkInfo := ctx.OtherModuleProvider(module, android.AdditionalSdkInfoProvider).(android.AdditionalSdkInfo)
+			info.memberSpecific = additionalSdkInfo.Properties
+
+			name2Info[name] = info
+		}
+		return info
+	}
+
+	for _, memberVariantDep := range memberVariantDeps {
+		propertyName := memberVariantDep.memberType.SdkPropertyName()
+		var list []string
+		if v, ok := sdkInfo.memberSpecific[propertyName]; ok {
+			list = v.([]string)
+		}
+
+		memberName := memberVariantDep.variant.Name()
+		list = append(list, memberName)
+		sdkInfo.memberSpecific[propertyName] = android.SortedUniqueStrings(list)
+
+		if memberVariantDep.container != nil {
+			containerInfo := getModuleInfo(memberVariantDep.container)
+			containerInfo.deps = android.SortedUniqueStrings(append(containerInfo.deps, memberName))
+		}
+
+		// Make sure that the module info is created for each module.
+		getModuleInfo(memberVariantDep.variant)
+	}
+
+	for _, memberName := range android.SortedStringKeys(name2Info) {
+		info := name2Info[memberName]
+		modules = append(modules, info)
+	}
+
+	return modules
 }
 
 // filterOutComponents removes any item from the deps list that is a component of another item in
@@ -1062,6 +1192,10 @@
 	return contents.content.String()
 }
 
+func (s *sdk) GetInfoContentsForTests() string {
+	return s.builderForTests.infoContents
+}
+
 func (s *sdk) GetUnversionedAndroidBpContentsForTests() string {
 	contents := &generatedContents{}
 	generateFilteredBpContents(contents, s.builderForTests.bpFile, func(module *bpModule) bool {
@@ -1116,6 +1250,9 @@
 
 	// The target build release for which the snapshot is to be generated.
 	targetBuildRelease *buildRelease
+
+	// The contents of the .info file that describes the sdk contents.
+	infoContents string
 }
 
 func (s *snapshotBuilder) CopyToSnapshot(src android.Path, dest string) {
@@ -1351,6 +1488,11 @@
 	// The variant that is added to the sdk.
 	variant android.SdkAware
 
+	// The optional container of this member, i.e. the module that is depended upon by the sdk
+	// (possibly transitively) and whose dependency on this module is why it was added to the sdk.
+	// Is nil if this a direct dependency of the sdk.
+	container android.SdkAware
+
 	// True if the member should be exported, i.e. accessible, from outside the sdk.
 	export bool
 
diff --git a/ui/build/build.go b/ui/build/build.go
index ec42b70..aadf4af 100644
--- a/ui/build/build.go
+++ b/ui/build/build.go
@@ -266,7 +266,6 @@
 	}
 
 	if config.StartRBE() {
-		cleanupRBELogsDir(ctx, config)
 		startRBE(ctx, config)
 		defer DumpRBEMetrics(ctx, config, filepath.Join(config.LogsDir(), "rbe_metrics.pb"))
 	}
diff --git a/ui/build/config.go b/ui/build/config.go
index 5765f21..e271bfc 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -19,14 +19,12 @@
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
-	"math/rand"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strconv"
 	"strings"
-	"syscall"
 	"time"
 
 	"android/soong/shared"
@@ -44,15 +42,6 @@
 	envConfigFetchTimeout = 10 * time.Second
 )
 
-var (
-	rbeRandPrefix int
-)
-
-func init() {
-	rand.Seed(time.Now().UnixNano())
-	rbeRandPrefix = rand.Intn(1000)
-}
-
 type Config struct{ *configImpl }
 
 type configImpl struct {
@@ -1155,25 +1144,34 @@
 	return true
 }
 
-func (c *configImpl) rbeProxyLogsDir() string {
-	for _, f := range []string{"RBE_proxy_log_dir", "FLAG_output_dir"} {
+func (c *configImpl) rbeLogDir() string {
+	for _, f := range []string{"RBE_log_dir", "FLAG_log_dir"} {
 		if v, ok := c.environ.Get(f); ok {
 			return v
 		}
 	}
-	buildTmpDir := shared.TempDirForOutDir(c.SoongOutDir())
-	return filepath.Join(buildTmpDir, "rbe")
+	if c.Dist() {
+		return c.LogsDir()
+	}
+	return c.OutDir()
 }
 
-func (c *configImpl) shouldCleanupRBELogsDir() bool {
-	// Perform a log directory cleanup only when the log directory
-	// is auto created by the build rather than user-specified.
-	for _, f := range []string{"RBE_proxy_log_dir", "FLAG_output_dir"} {
-		if _, ok := c.environ.Get(f); ok {
-			return false
+func (c *configImpl) rbeStatsOutputDir() string {
+	for _, f := range []string{"RBE_output_dir", "FLAG_output_dir"} {
+		if v, ok := c.environ.Get(f); ok {
+			return v
 		}
 	}
-	return true
+	return c.rbeLogDir()
+}
+
+func (c *configImpl) rbeLogPath() string {
+	for _, f := range []string{"RBE_log_path", "FLAG_log_path"} {
+		if v, ok := c.environ.Get(f); ok {
+			return v
+		}
+	}
+	return fmt.Sprintf("text://%v/reproxy_log.txt", c.rbeLogDir())
 }
 
 func (c *configImpl) rbeExecRoot() string {
@@ -1225,23 +1223,6 @@
 	return "RBE_use_application_default_credentials", "true"
 }
 
-func (c *configImpl) rbeSockAddr(dir string) (string, error) {
-	maxNameLen := len(syscall.RawSockaddrUnix{}.Path)
-	base := fmt.Sprintf("reproxy_%v.sock", rbeRandPrefix)
-
-	name := filepath.Join(dir, base)
-	if len(name) < maxNameLen {
-		return name, nil
-	}
-
-	name = filepath.Join("/tmp", base)
-	if len(name) < maxNameLen {
-		return name, nil
-	}
-
-	return "", fmt.Errorf("cannot generate a proxy socket address shorter than the limit of %v", maxNameLen)
-}
-
 func (c *configImpl) UseRemoteBuild() bool {
 	return c.UseGoma() || c.UseRBE()
 }
diff --git a/ui/build/rbe.go b/ui/build/rbe.go
index 3e558f7..8f9a699 100644
--- a/ui/build/rbe.go
+++ b/ui/build/rbe.go
@@ -16,9 +16,12 @@
 
 import (
 	"fmt"
+	"math/rand"
 	"os"
 	"path/filepath"
 	"runtime"
+	"syscall"
+	"time"
 
 	"android/soong/ui/metrics"
 )
@@ -51,16 +54,34 @@
 	return cmdPath
 }
 
+func sockAddr(dir string) (string, error) {
+	maxNameLen := len(syscall.RawSockaddrUnix{}.Path)
+	rand.Seed(time.Now().UnixNano())
+	base := fmt.Sprintf("reproxy_%v.sock", rand.Intn(1000))
+
+	name := filepath.Join(dir, base)
+	if len(name) < maxNameLen {
+		return name, nil
+	}
+
+	name = filepath.Join("/tmp", base)
+	if len(name) < maxNameLen {
+		return name, nil
+	}
+
+	return "", fmt.Errorf("cannot generate a proxy socket address shorter than the limit of %v", maxNameLen)
+}
+
 func getRBEVars(ctx Context, config Config) map[string]string {
 	vars := map[string]string{
-		"RBE_log_dir":    config.rbeProxyLogsDir(),
+		"RBE_log_path":   config.rbeLogPath(),
+		"RBE_log_dir":    config.rbeLogDir(),
 		"RBE_re_proxy":   config.rbeReproxy(),
 		"RBE_exec_root":  config.rbeExecRoot(),
-		"RBE_output_dir": config.rbeProxyLogsDir(),
-		"RBE_proxy_log_dir": config.rbeProxyLogsDir(),
+		"RBE_output_dir": config.rbeStatsOutputDir(),
 	}
 	if config.StartRBE() {
-		name, err := config.rbeSockAddr(absPath(ctx, config.TempDir()))
+		name, err := sockAddr(absPath(ctx, config.TempDir()))
 		if err != nil {
 			ctx.Fatalf("Error retrieving socket address: %v", err)
 			return nil
@@ -79,17 +100,6 @@
 	return vars
 }
 
-func cleanupRBELogsDir(ctx Context, config Config) {
-	if !config.shouldCleanupRBELogsDir() {
-		return
-	}
-
-	rbeTmpDir := config.rbeProxyLogsDir()
-	if err := os.RemoveAll(rbeTmpDir); err != nil {
-		fmt.Fprintln(ctx.Writer, "\033[33mUnable to remove RBE log directory: ", err, "\033[0m")
-	}
-}
-
 func startRBE(ctx Context, config Config) {
 	ctx.BeginTrace(metrics.RunSetupTool, "rbe_bootstrap")
 	defer ctx.EndTrace()
@@ -100,11 +110,6 @@
 	if n := ulimitOrFatal(ctx, config, "-n"); n < rbeLeastNFiles {
 		ctx.Fatalf("max open files is insufficient: %d; want >= %d.\n", n, rbeLeastNFiles)
 	}
-	if _, err := os.Stat(config.rbeProxyLogsDir()); os.IsNotExist(err) {
-		if err := os.MkdirAll(config.rbeProxyLogsDir(), 0744); err != nil {
-			ctx.Fatalf("Unable to create logs dir (%v) for RBE: %v", config.rbeProxyLogsDir, err)
-		}
-	}
 
 	cmd := Command(ctx, config, "startRBE bootstrap", rbeCommand(ctx, config, bootstrapCmd))
 
@@ -146,7 +151,7 @@
 		return
 	}
 
-	outputDir := config.rbeProxyLogsDir()
+	outputDir := config.rbeStatsOutputDir()
 	if outputDir == "" {
 		ctx.Fatal("RBE output dir variable not defined. Aborting metrics dumping.")
 	}
diff --git a/ui/build/rbe_test.go b/ui/build/rbe_test.go
index 266f76b..8ff96bc 100644
--- a/ui/build/rbe_test.go
+++ b/ui/build/rbe_test.go
@@ -56,8 +56,7 @@
 			env := Environment(tt.env)
 			env.Set("OUT_DIR", tmpDir)
 			env.Set("RBE_DIR", tmpDir)
-			env.Set("RBE_output_dir", tmpDir)
-			env.Set("RBE_proxy_log_dir", tmpDir)
+			env.Set("RBE_output_dir", t.TempDir())
 			config := Config{&configImpl{
 				environ: &env,
 			}}
diff --git a/ui/build/soong.go b/ui/build/soong.go
index c7f22f9..8992b4f 100644
--- a/ui/build/soong.go
+++ b/ui/build/soong.go
@@ -15,7 +15,9 @@
 package build
 
 import (
+	"errors"
 	"fmt"
+	"io/fs"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -491,10 +493,14 @@
 
 	ninja("bootstrap", "bootstrap.ninja", targets...)
 
-	var soongBuildMetrics *soong_metrics_proto.SoongBuildMetrics
 	if shouldCollectBuildSoongMetrics(config) {
 		soongBuildMetrics := loadSoongBuildMetrics(ctx, config)
-		logSoongBuildMetrics(ctx, soongBuildMetrics)
+		if soongBuildMetrics != nil {
+			logSoongBuildMetrics(ctx, soongBuildMetrics)
+			if ctx.Metrics != nil {
+				ctx.Metrics.SetSoongBuildMetrics(soongBuildMetrics)
+			}
+		}
 	}
 
 	distGzipFile(ctx, config, config.SoongNinjaFile(), "soong")
@@ -504,9 +510,6 @@
 		distGzipFile(ctx, config, config.SoongMakeVarsMk(), "soong")
 	}
 
-	if shouldCollectBuildSoongMetrics(config) && ctx.Metrics != nil {
-		ctx.Metrics.SetSoongBuildMetrics(soongBuildMetrics)
-	}
 	if config.JsonModuleGraph() {
 		distGzipFile(ctx, config, config.ModuleGraphFile(), "soong")
 	}
@@ -538,8 +541,12 @@
 
 func loadSoongBuildMetrics(ctx Context, config Config) *soong_metrics_proto.SoongBuildMetrics {
 	soongBuildMetricsFile := filepath.Join(config.LogsDir(), "soong_build_metrics.pb")
-	buf, err := ioutil.ReadFile(soongBuildMetricsFile)
-	if err != nil {
+	buf, err := os.ReadFile(soongBuildMetricsFile)
+	if errors.Is(err, fs.ErrNotExist) {
+		// Soong may not have run during this invocation
+          ctx.Verbosef("Failed to read metrics file, %s: %s", soongBuildMetricsFile, err)
+		return nil
+	} else if err != nil {
 		ctx.Fatalf("Failed to load %s: %s", soongBuildMetricsFile, err)
 	}
 	soongBuildMetrics := &soong_metrics_proto.SoongBuildMetrics{}