diff --git a/android/module.go b/android/module.go
index f5cfe66..e431ada 100644
--- a/android/module.go
+++ b/android/module.go
@@ -19,6 +19,7 @@
 	"os"
 	"path"
 	"path/filepath"
+	"regexp"
 	"strings"
 	"text/scanner"
 
@@ -135,6 +136,13 @@
 	// GetTagPath()[i] is the tag between GetWalkPath()[i] and GetWalkPath()[i+1]
 	GetTagPath() []blueprint.DependencyTag
 
+	// GetPathString is supposed to be called in visit function passed in WalkDeps()
+	// and returns a multi-line string showing the modules and dependency tags
+	// among them along the top-down dependency path from a start module to current child module.
+	// skipFirst when set to true, the output doesn't include the start module,
+	// which is already printed when this function is used along with ModuleErrorf().
+	GetPathString(skipFirst bool) string
+
 	AddMissingDependencies(missingDeps []string)
 
 	Target() Target
@@ -1734,6 +1742,41 @@
 	return b.tagPath
 }
 
+// A regexp for removing boilerplate from BaseDependencyTag from the string representation of
+// a dependency tag.
+var tagCleaner = regexp.MustCompile(`\QBaseDependencyTag:blueprint.BaseDependencyTag{}\E(, )?`)
+
+// PrettyPrintTag returns string representation of the tag, but prefers
+// custom String() method if available.
+func PrettyPrintTag(tag blueprint.DependencyTag) string {
+	// Use tag's custom String() method if available.
+	if stringer, ok := tag.(fmt.Stringer); ok {
+		return stringer.String()
+	}
+
+	// Otherwise, get a default string representation of the tag's struct.
+	tagString := fmt.Sprintf("%#v", tag)
+
+	// Remove the boilerplate from BaseDependencyTag as it adds no value.
+	tagString = tagCleaner.ReplaceAllString(tagString, "")
+	return tagString
+}
+
+func (b *baseModuleContext) GetPathString(skipFirst bool) string {
+	sb := strings.Builder{}
+	tagPath := b.GetTagPath()
+	walkPath := b.GetWalkPath()
+	if !skipFirst {
+		sb.WriteString(walkPath[0].String())
+	}
+	for i, m := range walkPath[1:] {
+		sb.WriteString("\n")
+		sb.WriteString(fmt.Sprintf("           via tag %s\n", PrettyPrintTag(tagPath[i])))
+		sb.WriteString(fmt.Sprintf("    -> %s", m.String()))
+	}
+	return sb.String()
+}
+
 func (m *moduleContext) VisitAllModuleVariants(visit func(Module)) {
 	m.bp.VisitAllModuleVariants(func(module blueprint.Module) {
 		visit(module.(Module))
diff --git a/android/sdk.go b/android/sdk.go
index 873e089..e823106 100644
--- a/android/sdk.go
+++ b/android/sdk.go
@@ -342,9 +342,24 @@
 	//
 	// * The variant property structs are analysed to find exported (capitalized) fields which
 	//   have common values. Those fields are cleared and the common value added to the common
-	//   properties. A field annotated with a tag of `sdk:"keep"` will be treated as if it
+	//   properties.
+	//
+	//   A field annotated with a tag of `sdk:"keep"` will be treated as if it
 	//   was not capitalized, i.e. not optimized for common values.
 	//
+	//   A field annotated with a tag of `android:"arch_variant"` will be allowed to have
+	//   values that differ by arch, fields not tagged as such must have common values across
+	//   all variants.
+	//
+	// * Additional field tags can be specified on a field that will ignore certain values
+	//   for the purpose of common value optimization. A value that is ignored must have the
+	//   default value for the property type. This is to ensure that significant value are not
+	//   ignored by accident. The purpose of this is to allow the snapshot generation to reflect
+	//   the behavior of the runtime. e.g. if a property is ignored on the host then a property
+	//   that is common for android can be treated as if it was common for android and host as
+	//   the setting for host is ignored anyway.
+	//   * `sdk:"ignored-on-host" - this indicates the property is ignored on the host variant.
+	//
 	// * The sdk module type populates the BpModule structure, creating the arch specific
 	//   structure and calls AddToPropertySet(...) on the properties struct to add the member
 	//   specific properties in the correct place in the structure.
diff --git a/apex/apex.go b/apex/apex.go
index 1947980..fa71ffa 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -18,7 +18,6 @@
 	"fmt"
 	"path"
 	"path/filepath"
-	"regexp"
 	"sort"
 	"strings"
 	"sync"
@@ -1811,24 +1810,6 @@
 	return intVer
 }
 
-// A regexp for removing boilerplate from BaseDependencyTag from the string representation of
-// a dependency tag.
-var tagCleaner = regexp.MustCompile(`\QBaseDependencyTag:blueprint.BaseDependencyTag{}\E(, )?`)
-
-func PrettyPrintTag(tag blueprint.DependencyTag) string {
-	// Use tag's custom String() method if available.
-	if stringer, ok := tag.(fmt.Stringer); ok {
-		return stringer.String()
-	}
-
-	// Otherwise, get a default string representation of the tag's struct.
-	tagString := fmt.Sprintf("%#v", tag)
-
-	// Remove the boilerplate from BaseDependencyTag as it adds no value.
-	tagString = tagCleaner.ReplaceAllString(tagString, "")
-	return tagString
-}
-
 // Ensures that the dependencies are marked as available for this APEX
 func (a *apexBundle) checkApexAvailability(ctx android.ModuleContext) {
 	// Let's be practical. Availability for test, host, and the VNDK apex isn't important
@@ -1863,14 +1844,7 @@
 		if to.AvailableFor(apexName) || whitelistedApexAvailable(apexName, toName) {
 			return true
 		}
-		message := ""
-		tagPath := ctx.GetTagPath()
-		// Skip the first module as that will be added at the start of the error message by ctx.ModuleErrorf().
-		walkPath := ctx.GetWalkPath()[1:]
-		for i, m := range walkPath {
-			message = fmt.Sprintf("%s\n           via tag %s\n    -> %s", message, PrettyPrintTag(tagPath[i]), m.String())
-		}
-		ctx.ModuleErrorf("%q requires %q that is not available for the APEX. Dependency path:%s", fromName, toName, message)
+		ctx.ModuleErrorf("%q requires %q that is not available for the APEX. Dependency path:%s", fromName, toName, ctx.GetPathString(true))
 		// Visit this module's dependencies to check and report any issues with their availability.
 		return true
 	})
@@ -2134,7 +2108,7 @@
 						filesInfo = append(filesInfo, apexFileForPrebuiltEtc(ctx, prebuilt, depName))
 					}
 				} else if am.CanHaveApexVariants() && am.IsInstallableToApex() {
-					ctx.ModuleErrorf("unexpected tag %s for indirect dependency %q", PrettyPrintTag(depTag), depName)
+					ctx.ModuleErrorf("unexpected tag %s for indirect dependency %q", android.PrettyPrintTag(depTag), depName)
 				}
 			}
 		}
diff --git a/cc/library_sdk_member.go b/cc/library_sdk_member.go
index 2c8e311..a7a1de2 100644
--- a/cc/library_sdk_member.go
+++ b/cc/library_sdk_member.go
@@ -307,7 +307,7 @@
 	// The list of possibly common exported include dirs.
 	//
 	// This field is exported as its contents may not be arch specific.
-	ExportedIncludeDirs android.Paths
+	ExportedIncludeDirs android.Paths `android:"arch_variant"`
 
 	// The list of arch specific exported generated include dirs.
 	//
@@ -322,27 +322,31 @@
 	// The list of possibly common exported system include dirs.
 	//
 	// This field is exported as its contents may not be arch specific.
-	ExportedSystemIncludeDirs android.Paths
+	ExportedSystemIncludeDirs android.Paths `android:"arch_variant"`
 
 	// The list of possibly common exported flags.
 	//
 	// This field is exported as its contents may not be arch specific.
-	ExportedFlags []string
+	ExportedFlags []string `android:"arch_variant"`
 
 	// The set of shared libraries
 	//
 	// This field is exported as its contents may not be arch specific.
-	SharedLibs []string
+	SharedLibs []string `android:"arch_variant"`
 
 	// The set of system shared libraries. Note nil and [] are semantically
 	// distinct - see BaseLinkerProperties.System_shared_libs.
 	//
 	// This field is exported as its contents may not be arch specific.
-	SystemSharedLibs []string
+	SystemSharedLibs []string `android:"arch_variant"`
 
 	// The specific stubs version for the lib variant, or empty string if stubs
 	// are not in use.
-	StubsVersion string
+	//
+	// Marked 'ignored-on-host' as the StubsVersion() from which this is initialized is
+	// not set on host and the stubs.versions property which this is written to is does
+	// not vary by arch so cannot be android specific.
+	StubsVersion string `sdk:"ignored-on-host"`
 
 	// outputFile is not exported as it is always arch specific.
 	outputFile android.Path
diff --git a/java/java.go b/java/java.go
index 472d3da..9d75c74 100644
--- a/java/java.go
+++ b/java/java.go
@@ -1906,7 +1906,7 @@
 type librarySdkMemberProperties struct {
 	android.SdkMemberPropertiesBase
 
-	JarToExport     android.Path
+	JarToExport     android.Path `android:"arch_variant"`
 	AidlIncludeDirs android.Paths
 }
 
diff --git a/java/java_test.go b/java/java_test.go
index e8a1a7c..0033f31 100644
--- a/java/java_test.go
+++ b/java/java_test.go
@@ -1229,6 +1229,24 @@
 	}
 }
 
+func TestJavaSdkLibrary_InvalidScopes(t *testing.T) {
+	testJavaError(t, `module "foo": enabled api scope "system" depends on disabled scope "public"`, `
+		java_sdk_library {
+			name: "foo",
+			srcs: ["a.java", "b.java"],
+			api_packages: ["foo"],
+			// Explicitly disable public to test the check that ensures the set of enabled
+			// scopes is consistent.
+			public: {
+				enabled: false,
+			},
+			system: {
+				enabled: true,
+			},
+		}
+		`)
+}
+
 var compilerFlagsTestCases = []struct {
 	in  string
 	out bool
diff --git a/java/sdk_library.go b/java/sdk_library.go
index 39c118d..fb51e10 100644
--- a/java/sdk_library.go
+++ b/java/sdk_library.go
@@ -70,6 +70,18 @@
 	// The api scope that this scope extends.
 	extends *apiScope
 
+	// The legacy enabled status for a specific scope can be dependent on other
+	// properties that have been specified on the library so it is provided by
+	// a function that can determine the status by examining those properties.
+	legacyEnabledStatus func(module *SdkLibrary) bool
+
+	// The default enabled status for non-legacy behavior, which is triggered by
+	// explicitly enabling at least one api scope.
+	defaultEnabledStatus bool
+
+	// Gets a pointer to the scope specific properties.
+	scopeSpecificProperties func(module *SdkLibrary) *ApiScopeProperties
+
 	// The name of the field in the dynamically created structure.
 	fieldName string
 
@@ -120,6 +132,10 @@
 	return baseName + sdkStubsSourceSuffix + scope.moduleSuffix
 }
 
+func (scope *apiScope) String() string {
+	return scope.name
+}
+
 type apiScopes []*apiScope
 
 func (scopes apiScopes) Strings(accessor func(*apiScope) string) []string {
@@ -132,30 +148,68 @@
 
 var (
 	apiScopePublic = initApiScope(&apiScope{
-		name:       "public",
+		name: "public",
+
+		// Public scope is enabled by default for both legacy and non-legacy modes.
+		legacyEnabledStatus: func(module *SdkLibrary) bool {
+			return true
+		},
+		defaultEnabledStatus: true,
+
+		scopeSpecificProperties: func(module *SdkLibrary) *ApiScopeProperties {
+			return &module.sdkLibraryProperties.Public
+		},
 		sdkVersion: "current",
 	})
 	apiScopeSystem = initApiScope(&apiScope{
-		name:           "system",
-		extends:        apiScopePublic,
+		name:                "system",
+		extends:             apiScopePublic,
+		legacyEnabledStatus: (*SdkLibrary).generateTestAndSystemScopesByDefault,
+		scopeSpecificProperties: func(module *SdkLibrary) *ApiScopeProperties {
+			return &module.sdkLibraryProperties.System
+		},
 		apiFilePrefix:  "system-",
 		moduleSuffix:   sdkSystemApiSuffix,
 		sdkVersion:     "system_current",
 		droidstubsArgs: []string{"-showAnnotation android.annotation.SystemApi"},
 	})
 	apiScopeTest = initApiScope(&apiScope{
-		name:           "test",
-		extends:        apiScopePublic,
+		name:                "test",
+		extends:             apiScopePublic,
+		legacyEnabledStatus: (*SdkLibrary).generateTestAndSystemScopesByDefault,
+		scopeSpecificProperties: func(module *SdkLibrary) *ApiScopeProperties {
+			return &module.sdkLibraryProperties.Test
+		},
 		apiFilePrefix:  "test-",
 		moduleSuffix:   sdkTestApiSuffix,
 		sdkVersion:     "test_current",
 		droidstubsArgs: []string{"-showAnnotation android.annotation.TestApi"},
 		unstable:       true,
 	})
+	apiScopeModuleLib = initApiScope(&apiScope{
+		name:    "module_lib",
+		extends: apiScopeSystem,
+		// Module_lib scope is disabled by default in legacy mode.
+		//
+		// Enabling this would break existing usages.
+		legacyEnabledStatus: func(module *SdkLibrary) bool {
+			return false
+		},
+		scopeSpecificProperties: func(module *SdkLibrary) *ApiScopeProperties {
+			return &module.sdkLibraryProperties.Module_lib
+		},
+		apiFilePrefix: "module-lib-",
+		moduleSuffix:  ".module_lib",
+		sdkVersion:    "module_current",
+		droidstubsArgs: []string{
+			"--show-annotation android.annotation.SystemApi\\(client=android.annotation.SystemApi.Client.MODULE_LIBRARIES\\)",
+		},
+	})
 	allApiScopes = apiScopes{
 		apiScopePublic,
 		apiScopeSystem,
 		apiScopeTest,
+		apiScopeModuleLib,
 	}
 )
 
@@ -190,6 +244,18 @@
 	ctx.RegisterModuleType("java_sdk_library_import", sdkLibraryImportFactory)
 }
 
+// Properties associated with each api scope.
+type ApiScopeProperties struct {
+	// Indicates whether the api surface is generated.
+	//
+	// If this is set for any scope then all scopes must explicitly specify if they
+	// are enabled. This is to prevent new usages from depending on legacy behavior.
+	//
+	// Otherwise, if this is not set for any scope then the default  behavior is
+	// scope specific so please refer to the scope specific property documentation.
+	Enabled *bool
+}
+
 type sdkLibraryProperties struct {
 	// List of Java libraries that will be in the classpath when building stubs
 	Stub_only_libs []string `android:"arch_variant"`
@@ -232,8 +298,36 @@
 	// don't create dist rules.
 	No_dist *bool `blueprint:"mutated"`
 
-	// indicates whether system and test apis should be managed.
-	Has_system_and_test_apis bool `blueprint:"mutated"`
+	// indicates whether system and test apis should be generated.
+	Generate_system_and_test_apis bool `blueprint:"mutated"`
+
+	// The properties specific to the public api scope
+	//
+	// Unless explicitly specified by using public.enabled the public api scope is
+	// enabled by default in both legacy and non-legacy mode.
+	Public ApiScopeProperties
+
+	// The properties specific to the system api scope
+	//
+	// In legacy mode the system api scope is enabled by default when sdk_version
+	// is set to something other than "none".
+	//
+	// In non-legacy mode the system api scope is disabled by default.
+	System ApiScopeProperties
+
+	// The properties specific to the test api scope
+	//
+	// In legacy mode the test api scope is enabled by default when sdk_version
+	// is set to something other than "none".
+	//
+	// In non-legacy mode the test api scope is disabled by default.
+	Test ApiScopeProperties
+
+	// The properties specific to the module_lib api scope
+	//
+	// Unless explicitly specified by using test.enabled the module_lib api scope is
+	// disabled by default.
+	Module_lib ApiScopeProperties
 
 	// TODO: determines whether to create HTML doc or not
 	//Html_doc *bool
@@ -270,18 +364,65 @@
 
 	sdkLibraryProperties sdkLibraryProperties
 
+	// Map from api scope to the scope specific property structure.
+	scopeToProperties map[*apiScope]*ApiScopeProperties
+
 	commonToSdkLibraryAndImport
 }
 
 var _ Dependency = (*SdkLibrary)(nil)
 var _ SdkLibraryDependency = (*SdkLibrary)(nil)
 
-func (module *SdkLibrary) getActiveApiScopes() apiScopes {
-	if module.sdkLibraryProperties.Has_system_and_test_apis {
-		return allApiScopes
-	} else {
-		return apiScopes{apiScopePublic}
+func (module *SdkLibrary) generateTestAndSystemScopesByDefault() bool {
+	return module.sdkLibraryProperties.Generate_system_and_test_apis
+}
+
+func (module *SdkLibrary) getGeneratedApiScopes(ctx android.EarlyModuleContext) apiScopes {
+	// Check to see if any scopes have been explicitly enabled. If any have then all
+	// must be.
+	anyScopesExplicitlyEnabled := false
+	for _, scope := range allApiScopes {
+		scopeProperties := module.scopeToProperties[scope]
+		if scopeProperties.Enabled != nil {
+			anyScopesExplicitlyEnabled = true
+			break
+		}
 	}
+
+	var generatedScopes apiScopes
+	enabledScopes := make(map[*apiScope]struct{})
+	for _, scope := range allApiScopes {
+		scopeProperties := module.scopeToProperties[scope]
+		// If any scopes are explicitly enabled then ignore the legacy enabled status.
+		// This is to ensure that any new usages of this module type do not rely on legacy
+		// behaviour.
+		defaultEnabledStatus := false
+		if anyScopesExplicitlyEnabled {
+			defaultEnabledStatus = scope.defaultEnabledStatus
+		} else {
+			defaultEnabledStatus = scope.legacyEnabledStatus(module)
+		}
+		enabled := proptools.BoolDefault(scopeProperties.Enabled, defaultEnabledStatus)
+		if enabled {
+			enabledScopes[scope] = struct{}{}
+			generatedScopes = append(generatedScopes, scope)
+		}
+	}
+
+	// Now check to make sure that any scope that is extended by an enabled scope is also
+	// enabled.
+	for _, scope := range allApiScopes {
+		if _, ok := enabledScopes[scope]; ok {
+			extends := scope.extends
+			if extends != nil {
+				if _, ok := enabledScopes[extends]; !ok {
+					ctx.ModuleErrorf("enabled api scope %q depends on disabled scope %q", scope, extends)
+				}
+			}
+		}
+	}
+
+	return generatedScopes
 }
 
 var xmlPermissionsFileTag = dependencyTag{name: "xml-permissions-file"}
@@ -294,7 +435,7 @@
 }
 
 func (module *SdkLibrary) DepsMutator(ctx android.BottomUpMutatorContext) {
-	for _, apiScope := range module.getActiveApiScopes() {
+	for _, apiScope := range module.getGeneratedApiScopes(ctx) {
 		// Add dependencies to the stubs library
 		ctx.AddVariationDependencies(nil, apiScope.stubsTag, module.stubsName(apiScope))
 
@@ -734,15 +875,15 @@
 	// also assume it does not contribute to the dist build.
 	sdkDep := decodeSdkDep(mctx, sdkContext(&module.Library))
 	hasSystemAndTestApis := sdkDep.hasStandardLibs()
-	module.sdkLibraryProperties.Has_system_and_test_apis = hasSystemAndTestApis
+	module.sdkLibraryProperties.Generate_system_and_test_apis = hasSystemAndTestApis
 	module.sdkLibraryProperties.No_dist = proptools.BoolPtr(!hasSystemAndTestApis)
 
 	missing_current_api := false
 
-	activeScopes := module.getActiveApiScopes()
+	generatedScopes := module.getGeneratedApiScopes(mctx)
 
 	apiDir := module.getApiDir()
-	for _, scope := range activeScopes {
+	for _, scope := range generatedScopes {
 		for _, api := range []string{"current.txt", "removed.txt"} {
 			path := path.Join(mctx.ModuleDir(), apiDir, scope.apiFilePrefix+api)
 			p := android.ExistentPathForSource(mctx, path)
@@ -765,11 +906,11 @@
 			"You can update them by:\n"+
 			"%s %q %s && m update-api",
 			script, filepath.Join(mctx.ModuleDir(), apiDir),
-			strings.Join(activeScopes.Strings(func(s *apiScope) string { return s.apiFilePrefix }), " "))
+			strings.Join(generatedScopes.Strings(func(s *apiScope) string { return s.apiFilePrefix }), " "))
 		return
 	}
 
-	for _, scope := range activeScopes {
+	for _, scope := range generatedScopes {
 		module.createStubsLibrary(mctx, scope)
 		module.createStubsSources(mctx, scope)
 	}
@@ -809,6 +950,14 @@
 	module.InitSdkLibraryProperties()
 	android.InitApexModule(module)
 	InitJavaModule(module, android.HostAndDeviceSupported)
+
+	// Initialize the map from scope to scope specific properties.
+	scopeToProperties := make(map[*apiScope]*ApiScopeProperties)
+	for _, scope := range allApiScopes {
+		scopeToProperties[scope] = scope.scopeSpecificProperties(module)
+	}
+	module.scopeToProperties = scopeToProperties
+
 	module.SetDefaultableHook(func(ctx android.DefaultableHookContext) { module.CreateInternalModules(ctx) })
 	return module
 }
diff --git a/sdk/cc_sdk_test.go b/sdk/cc_sdk_test.go
index 733f7ac..b77447a 100644
--- a/sdk/cc_sdk_test.go
+++ b/sdk/cc_sdk_test.go
@@ -1805,3 +1805,86 @@
 }
 `))
 }
+
+func TestDeviceAndHostSnapshotWithStubsLibrary(t *testing.T) {
+	result := testSdkWithCc(t, `
+		sdk {
+			name: "mysdk",
+			host_supported: true,
+			native_shared_libs: ["stubslib"],
+		}
+
+		cc_library {
+			name: "internaldep",
+			host_supported: true,
+		}
+
+		cc_library {
+			name: "stubslib",
+			host_supported: true,
+			shared_libs: ["internaldep"],
+			stubs: {
+				symbol_file: "some/where/stubslib.map.txt",
+				versions: ["1", "2", "3"],
+			},
+		}
+	`)
+
+	result.CheckSnapshot("mysdk", "",
+		checkAndroidBpContents(`
+// This is auto-generated. DO NOT EDIT.
+
+cc_prebuilt_library_shared {
+    name: "mysdk_stubslib@current",
+    sdk_member_name: "stubslib",
+    host_supported: true,
+    installable: false,
+    stubs: {
+        versions: ["3"],
+    },
+    target: {
+        android_arm64: {
+            srcs: ["android/arm64/lib/stubslib.so"],
+        },
+        android_arm: {
+            srcs: ["android/arm/lib/stubslib.so"],
+        },
+        linux_glibc_x86_64: {
+            srcs: ["linux_glibc/x86_64/lib/stubslib.so"],
+        },
+        linux_glibc_x86: {
+            srcs: ["linux_glibc/x86/lib/stubslib.so"],
+        },
+    },
+}
+
+cc_prebuilt_library_shared {
+    name: "stubslib",
+    prefer: false,
+    host_supported: true,
+    stubs: {
+        versions: ["3"],
+    },
+    target: {
+        android_arm64: {
+            srcs: ["android/arm64/lib/stubslib.so"],
+        },
+        android_arm: {
+            srcs: ["android/arm/lib/stubslib.so"],
+        },
+        linux_glibc_x86_64: {
+            srcs: ["linux_glibc/x86_64/lib/stubslib.so"],
+        },
+        linux_glibc_x86: {
+            srcs: ["linux_glibc/x86/lib/stubslib.so"],
+        },
+    },
+}
+
+sdk_snapshot {
+    name: "mysdk@current",
+    host_supported: true,
+    native_shared_libs: ["mysdk_stubslib@current"],
+}
+`))
+}
diff --git a/sdk/java_sdk_test.go b/sdk/java_sdk_test.go
index 788d016..6173510 100644
--- a/sdk/java_sdk_test.go
+++ b/sdk/java_sdk_test.go
@@ -32,6 +32,8 @@
 		"api/system-removed.txt":                            nil,
 		"api/test-current.txt":                              nil,
 		"api/test-removed.txt":                              nil,
+		"api/module-lib-current.txt":                        nil,
+		"api/module-lib-removed.txt":                        nil,
 		"build/soong/scripts/gen-java-current-api-files.sh": nil,
 	}
 
@@ -56,6 +58,9 @@
 	name: "android_test_stubs_current",
 }
 java_import {
+	name: "android_module_lib_stubs_current",
+}
+java_import {
 	name: "core-lambda-stubs", 
 	sdk_version: "none",
 }
@@ -1067,3 +1072,194 @@
 			".intermediates/mysdk/common_os/tmp/sdk_library/test/myjavalib_stub_sources.zip"),
 	)
 }
+
+func TestSnapshotWithJavaSdkLibrary_ApiSurfaces(t *testing.T) {
+	result := testSdkWithJava(t, `
+		sdk {
+			name: "mysdk",
+			java_sdk_libs: ["myjavalib"],
+		}
+
+		java_sdk_library {
+			name: "myjavalib",
+			apex_available: ["//apex_available:anyapex"],
+			srcs: ["Test.java"],
+			sdk_version: "current",
+			public: {
+				enabled: true,
+			},
+			system: {
+				enabled: true,
+			},
+		}
+	`)
+
+	result.CheckSnapshot("mysdk", "",
+		checkAndroidBpContents(`
+// This is auto-generated. DO NOT EDIT.
+
+java_sdk_library_import {
+    name: "mysdk_myjavalib@current",
+    sdk_member_name: "myjavalib",
+    apex_available: ["//apex_available:anyapex"],
+    public: {
+        jars: ["sdk_library/public/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/public/myjavalib_stub_sources"],
+        current_api: "sdk_library/public/myjavalib.txt",
+        removed_api: "sdk_library/public/myjavalib-removed.txt",
+        sdk_version: "current",
+    },
+    system: {
+        jars: ["sdk_library/system/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/system/myjavalib_stub_sources"],
+        current_api: "sdk_library/system/myjavalib.txt",
+        removed_api: "sdk_library/system/myjavalib-removed.txt",
+        sdk_version: "system_current",
+    },
+}
+
+java_sdk_library_import {
+    name: "myjavalib",
+    prefer: false,
+    apex_available: ["//apex_available:anyapex"],
+    public: {
+        jars: ["sdk_library/public/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/public/myjavalib_stub_sources"],
+        current_api: "sdk_library/public/myjavalib.txt",
+        removed_api: "sdk_library/public/myjavalib-removed.txt",
+        sdk_version: "current",
+    },
+    system: {
+        jars: ["sdk_library/system/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/system/myjavalib_stub_sources"],
+        current_api: "sdk_library/system/myjavalib.txt",
+        removed_api: "sdk_library/system/myjavalib-removed.txt",
+        sdk_version: "system_current",
+    },
+}
+
+sdk_snapshot {
+    name: "mysdk@current",
+    java_sdk_libs: ["mysdk_myjavalib@current"],
+}
+`),
+		checkAllCopyRules(`
+.intermediates/myjavalib.stubs/android_common/javac/myjavalib.stubs.jar -> sdk_library/public/myjavalib-stubs.jar
+.intermediates/myjavalib.stubs.source/android_common/myjavalib.stubs.source_api.txt -> sdk_library/public/myjavalib.txt
+.intermediates/myjavalib.stubs.source/android_common/myjavalib.stubs.source_api.txt -> sdk_library/public/myjavalib-removed.txt
+.intermediates/myjavalib.stubs.system/android_common/javac/myjavalib.stubs.system.jar -> sdk_library/system/myjavalib-stubs.jar
+.intermediates/myjavalib.stubs.source.system/android_common/myjavalib.stubs.source.system_api.txt -> sdk_library/system/myjavalib.txt
+.intermediates/myjavalib.stubs.source.system/android_common/myjavalib.stubs.source.system_api.txt -> sdk_library/system/myjavalib-removed.txt
+`),
+		checkMergeZips(
+			".intermediates/mysdk/common_os/tmp/sdk_library/public/myjavalib_stub_sources.zip",
+			".intermediates/mysdk/common_os/tmp/sdk_library/system/myjavalib_stub_sources.zip",
+		),
+	)
+}
+
+func TestSnapshotWithJavaSdkLibrary_ModuleLib(t *testing.T) {
+	result := testSdkWithJava(t, `
+		sdk {
+			name: "mysdk",
+			java_sdk_libs: ["myjavalib"],
+		}
+
+		java_sdk_library {
+			name: "myjavalib",
+			apex_available: ["//apex_available:anyapex"],
+			srcs: ["Test.java"],
+			sdk_version: "current",
+			public: {
+				enabled: true,
+			},
+			system: {
+				enabled: true,
+			},
+			module_lib: {
+				enabled: true,
+			},
+		}
+	`)
+
+	result.CheckSnapshot("mysdk", "",
+		checkAndroidBpContents(`
+// This is auto-generated. DO NOT EDIT.
+
+java_sdk_library_import {
+    name: "mysdk_myjavalib@current",
+    sdk_member_name: "myjavalib",
+    apex_available: ["//apex_available:anyapex"],
+    public: {
+        jars: ["sdk_library/public/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/public/myjavalib_stub_sources"],
+        current_api: "sdk_library/public/myjavalib.txt",
+        removed_api: "sdk_library/public/myjavalib-removed.txt",
+        sdk_version: "current",
+    },
+    system: {
+        jars: ["sdk_library/system/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/system/myjavalib_stub_sources"],
+        current_api: "sdk_library/system/myjavalib.txt",
+        removed_api: "sdk_library/system/myjavalib-removed.txt",
+        sdk_version: "system_current",
+    },
+    module_lib: {
+        jars: ["sdk_library/module_lib/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/module_lib/myjavalib_stub_sources"],
+        current_api: "sdk_library/module_lib/myjavalib.txt",
+        removed_api: "sdk_library/module_lib/myjavalib-removed.txt",
+        sdk_version: "module_current",
+    },
+}
+
+java_sdk_library_import {
+    name: "myjavalib",
+    prefer: false,
+    apex_available: ["//apex_available:anyapex"],
+    public: {
+        jars: ["sdk_library/public/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/public/myjavalib_stub_sources"],
+        current_api: "sdk_library/public/myjavalib.txt",
+        removed_api: "sdk_library/public/myjavalib-removed.txt",
+        sdk_version: "current",
+    },
+    system: {
+        jars: ["sdk_library/system/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/system/myjavalib_stub_sources"],
+        current_api: "sdk_library/system/myjavalib.txt",
+        removed_api: "sdk_library/system/myjavalib-removed.txt",
+        sdk_version: "system_current",
+    },
+    module_lib: {
+        jars: ["sdk_library/module_lib/myjavalib-stubs.jar"],
+        stub_srcs: ["sdk_library/module_lib/myjavalib_stub_sources"],
+        current_api: "sdk_library/module_lib/myjavalib.txt",
+        removed_api: "sdk_library/module_lib/myjavalib-removed.txt",
+        sdk_version: "module_current",
+    },
+}
+
+sdk_snapshot {
+    name: "mysdk@current",
+    java_sdk_libs: ["mysdk_myjavalib@current"],
+}
+`),
+		checkAllCopyRules(`
+.intermediates/myjavalib.stubs/android_common/javac/myjavalib.stubs.jar -> sdk_library/public/myjavalib-stubs.jar
+.intermediates/myjavalib.stubs.source/android_common/myjavalib.stubs.source_api.txt -> sdk_library/public/myjavalib.txt
+.intermediates/myjavalib.stubs.source/android_common/myjavalib.stubs.source_api.txt -> sdk_library/public/myjavalib-removed.txt
+.intermediates/myjavalib.stubs.system/android_common/javac/myjavalib.stubs.system.jar -> sdk_library/system/myjavalib-stubs.jar
+.intermediates/myjavalib.stubs.source.system/android_common/myjavalib.stubs.source.system_api.txt -> sdk_library/system/myjavalib.txt
+.intermediates/myjavalib.stubs.source.system/android_common/myjavalib.stubs.source.system_api.txt -> sdk_library/system/myjavalib-removed.txt
+.intermediates/myjavalib.stubs.module_lib/android_common/javac/myjavalib.stubs.module_lib.jar -> sdk_library/module_lib/myjavalib-stubs.jar
+.intermediates/myjavalib.stubs.source.module_lib/android_common/myjavalib.stubs.source.module_lib_api.txt -> sdk_library/module_lib/myjavalib.txt
+.intermediates/myjavalib.stubs.source.module_lib/android_common/myjavalib.stubs.source.module_lib_api.txt -> sdk_library/module_lib/myjavalib-removed.txt
+`),
+		checkMergeZips(
+			".intermediates/mysdk/common_os/tmp/sdk_library/public/myjavalib_stub_sources.zip",
+			".intermediates/mysdk/common_os/tmp/sdk_library/system/myjavalib_stub_sources.zip",
+			".intermediates/mysdk/common_os/tmp/sdk_library/module_lib/myjavalib_stub_sources.zip",
+		),
+	)
+}
diff --git a/sdk/sdk_test.go b/sdk/sdk_test.go
index 095f836..ae1a492 100644
--- a/sdk/sdk_test.go
+++ b/sdk/sdk_test.go
@@ -226,8 +226,8 @@
 }
 
 type EmbeddedPropertiesStruct struct {
-	S_Embedded_Common    string
-	S_Embedded_Different string
+	S_Embedded_Common    string `android:"arch_variant"`
+	S_Embedded_Different string `android:"arch_variant"`
 }
 
 type testPropertiesStruct struct {
@@ -235,11 +235,11 @@
 	private     string
 	Public_Kept string `sdk:"keep"`
 	S_Common    string
-	S_Different string
+	S_Different string `android:"arch_variant"`
 	A_Common    []string
-	A_Different []string
+	A_Different []string `android:"arch_variant"`
 	F_Common    *bool
-	F_Different *bool
+	F_Different *bool `android:"arch_variant"`
 	EmbeddedPropertiesStruct
 }
 
@@ -289,9 +289,12 @@
 	}
 
 	extractor := newCommonValueExtractor(common)
-	extractor.extractCommonProperties(common, structs)
 
 	h := TestHelper{t}
+
+	err := extractor.extractCommonProperties(common, structs)
+	h.AssertDeepEquals("unexpected error", nil, err)
+
 	h.AssertDeepEquals("common properties not correct",
 		&testPropertiesStruct{
 			name:        "common",
@@ -346,3 +349,26 @@
 		},
 		structs[1])
 }
+
+func TestCommonValueOptimization_InvalidArchSpecificVariants(t *testing.T) {
+	common := &testPropertiesStruct{name: "common"}
+	structs := []propertiesContainer{
+		&testPropertiesStruct{
+			name:     "struct-0",
+			S_Common: "should-be-but-is-not-common0",
+		},
+		&testPropertiesStruct{
+			name:     "struct-1",
+			S_Common: "should-be-but-is-not-common1",
+		},
+	}
+
+	extractor := newCommonValueExtractor(common)
+
+	h := TestHelper{t}
+
+	err := extractor.extractCommonProperties(common, structs)
+	h.AssertErrorMessageEquals("unexpected error", `field "S_Common" is not tagged as "arch_variant" but has arch specific properties:
+    "struct-0" has value "should-be-but-is-not-common0"
+    "struct-1" has value "should-be-but-is-not-common1"`, err)
+}
diff --git a/sdk/update.go b/sdk/update.go
index 03a5c03..d43a42d 100644
--- a/sdk/update.go
+++ b/sdk/update.go
@@ -982,6 +982,13 @@
 	}
 }
 
+func (osInfo *osTypeSpecificInfo) isHostVariant() bool {
+	osClass := osInfo.osType.Class
+	return osClass == android.Host || osClass == android.HostCross
+}
+
+var _ isHostVariant = (*osTypeSpecificInfo)(nil)
+
 func (osInfo *osTypeSpecificInfo) String() string {
 	return fmt.Sprintf("OsType{%s}", osInfo.osType)
 }
@@ -1215,16 +1222,34 @@
 // struct (or one of its embedded structs).
 type fieldAccessorFunc func(structValue reflect.Value) reflect.Value
 
+// Checks the metadata to determine whether the property should be ignored for the
+// purposes of common value extraction or not.
+type extractorMetadataPredicate func(metadata propertiesContainer) bool
+
+// Indicates whether optimizable properties are provided by a host variant or
+// not.
+type isHostVariant interface {
+	isHostVariant() bool
+}
+
 // A property that can be optimized by the commonValueExtractor.
 type extractorProperty struct {
 	// The name of the field for this property.
 	name string
 
+	// Filter that can use metadata associated with the properties being optimized
+	// to determine whether the field should be ignored during common value
+	// optimization.
+	filter extractorMetadataPredicate
+
 	// Retrieves the value on which common value optimization will be performed.
 	getter fieldAccessorFunc
 
 	// The empty value for the field.
 	emptyValue reflect.Value
+
+	// True if the property can support arch variants false otherwise.
+	archVariant bool
 }
 
 func (p extractorProperty) String() string {
@@ -1270,6 +1295,20 @@
 			continue
 		}
 
+		var filter extractorMetadataPredicate
+
+		// Add a filter
+		if proptools.HasTag(field, "sdk", "ignored-on-host") {
+			filter = func(metadata propertiesContainer) bool {
+				if m, ok := metadata.(isHostVariant); ok {
+					if m.isHostVariant() {
+						return false
+					}
+				}
+				return true
+			}
+		}
+
 		// Save a copy of the field index for use in the function.
 		fieldIndex := f
 
@@ -1301,8 +1340,10 @@
 		} else {
 			property := extractorProperty{
 				name,
+				filter,
 				fieldGetter,
 				reflect.Zero(field.Type),
+				proptools.HasTag(field, "android", "arch_variant"),
 			}
 			e.properties = append(e.properties, property)
 		}
@@ -1368,17 +1409,38 @@
 
 	for _, property := range e.properties {
 		fieldGetter := property.getter
+		filter := property.filter
+		if filter == nil {
+			filter = func(metadata propertiesContainer) bool {
+				return true
+			}
+		}
 
 		// Check to see if all the structures have the same value for the field. The commonValue
-		// is nil on entry to the loop and if it is nil on exit then there is no common value,
-		// otherwise it points to the common value.
+		// is nil on entry to the loop and if it is nil on exit then there is no common value or
+		// all the values have been filtered out, otherwise it points to the common value.
 		var commonValue *reflect.Value
 
+		// Assume that all the values will be the same.
+		//
+		// While similar to this is not quite the same as commonValue == nil. If all the values
+		// have been filtered out then this will be false but commonValue == nil will be true.
+		valuesDiffer := false
+
 		for i := 0; i < sliceValue.Len(); i++ {
 			container := sliceValue.Index(i).Interface().(propertiesContainer)
 			itemValue := reflect.ValueOf(container.optimizableProperties())
 			fieldValue := fieldGetter(itemValue)
 
+			if !filter(container) {
+				expectedValue := property.emptyValue.Interface()
+				actualValue := fieldValue.Interface()
+				if !reflect.DeepEqual(expectedValue, actualValue) {
+					return fmt.Errorf("field %q is supposed to be ignored for %q but is set to %#v instead of %#v", property, container, actualValue, expectedValue)
+				}
+				continue
+			}
+
 			if commonValue == nil {
 				// Use the first value as the commonProperties value.
 				commonValue = &fieldValue
@@ -1387,12 +1449,13 @@
 				// no value in common so break out.
 				if !reflect.DeepEqual(fieldValue.Interface(), commonValue.Interface()) {
 					commonValue = nil
+					valuesDiffer = true
 					break
 				}
 			}
 		}
 
-		// If the fields all have a common value then store it in the common struct field
+		// If the fields all have common value then store it in the common struct field
 		// and set the input struct's field to the empty value.
 		if commonValue != nil {
 			emptyValue := property.emptyValue
@@ -1404,6 +1467,21 @@
 				fieldValue.Set(emptyValue)
 			}
 		}
+
+		if valuesDiffer && !property.archVariant {
+			// The values differ but the property does not support arch variants so it
+			// is an error.
+			var details strings.Builder
+			for i := 0; i < sliceValue.Len(); i++ {
+				container := sliceValue.Index(i).Interface().(propertiesContainer)
+				itemValue := reflect.ValueOf(container.optimizableProperties())
+				fieldValue := fieldGetter(itemValue)
+
+				_, _ = fmt.Fprintf(&details, "\n    %q has value %q", container.String(), fieldValue.Interface())
+			}
+
+			return fmt.Errorf("field %q is not tagged as \"arch_variant\" but has arch specific properties:%s", property.String(), details.String())
+		}
 	}
 
 	return nil
diff --git a/ui/build/cleanbuild.go b/ui/build/cleanbuild.go
index 0bcdccb..e1123e0 100644
--- a/ui/build/cleanbuild.go
+++ b/ui/build/cleanbuild.go
@@ -104,6 +104,7 @@
 		productOut("*.img"),
 		productOut("*.zip"),
 		productOut("android-info.txt"),
+		productOut("misc_info.txt"),
 		productOut("apex"),
 		productOut("kernel"),
 		productOut("data"),