Merge "Copy shared_libs and system_shared_libs to module snapshot"

android/sdk.go

@@ -186,9 +186,33 @@ type SnapshotBuilder interface {
 	// is correctly output for both versioned and unversioned prebuilts in the
 	// snapshot.
 	//
+	// "required: true" means that the property must only contain references
+	// to other members of the sdk. Passing a reference to a module that is not a
+	// member of the sdk will result in a build error.
+	//
+	// "required: false" means that the property can contain references to modules
+	// that are either members or not members of the sdk. If a reference is to a
+	// module that is a non member then the reference is left unchanged, i.e. it
+	// is not transformed as references to members are.
+	//
+	// The handling of the member names is dependent on whether it is an internal or
+	// exported member. An exported member is one whose name is specified in one of
+	// the member type specific properties. An internal member is one that is added
+	// due to being a part of an exported (or other internal) member and is not itself
+	// an exported member.
+	//
+	// Member names are handled as follows:
+	// * When creating the unversioned form of the module the name is left unchecked
+	//   unless the member is internal in which case it is transformed into an sdk
+	//   specific name, i.e. by prefixing with the sdk name.
+	//
+	// * When creating the versioned form of the module the name is transformed into
+	//   a versioned sdk specific name, i.e. by prefixing with the sdk name and
+	//   suffixing with the version.
+	//
 	// e.g.
-	// bpPropertySet.AddPropertyWithTag("libs", []string{"member1", "member2"}, builder.SdkMemberReferencePropertyTag())
+	// bpPropertySet.AddPropertyWithTag("libs", []string{"member1", "member2"}, builder.SdkMemberReferencePropertyTag(true))
-	SdkMemberReferencePropertyTag() BpPropertyTag
+	SdkMemberReferencePropertyTag(required bool) BpPropertyTag
 }
 
 type BpPropertyTag interface{}

cc/binary_sdk_member.go

@@ -95,6 +95,16 @@ type nativeBinaryInfoProperties struct {
 
 	// outputFile is not exported as it is always arch specific.
 	outputFile android.Path
+
+	// The set of shared libraries
+	//
+	// This field is exported as its contents may not be arch specific.
+	SharedLibs []string
+
+	// The set of system shared libraries
+	//
+	// This field is exported as its contents may not be arch specific.
+	SystemSharedLibs []string
 }
 
 func (p *nativeBinaryInfoProperties) PopulateFromVariant(variant android.SdkAware) {
@@ -102,6 +112,14 @@ func (p *nativeBinaryInfoProperties) PopulateFromVariant(variant android.SdkAwar
 
 	p.archType = ccModule.Target().Arch.ArchType.String()
 	p.outputFile = ccModule.OutputFile().Path()
+
+	if ccModule.linker != nil {
+		specifiedDeps := specifiedDeps{}
+		specifiedDeps = ccModule.linker.linkerSpecifiedDeps(specifiedDeps)
+
+		p.SharedLibs = specifiedDeps.sharedLibs
+		p.SystemSharedLibs = specifiedDeps.systemSharedLibs
+	}
 }
 
 func (p *nativeBinaryInfoProperties) AddToPropertySet(sdkModuleContext android.ModuleContext, builder android.SnapshotBuilder, propertySet android.BpPropertySet) {
@@ -114,4 +132,12 @@ func (p *nativeBinaryInfoProperties) AddToPropertySet(sdkModuleContext android.M
 
 		builder.CopyToSnapshot(p.outputFile, nativeBinaryPathFor(*p))
 	}
+
+	if len(p.SharedLibs) > 0 {
+		propertySet.AddPropertyWithTag("shared_libs", p.SharedLibs, builder.SdkMemberReferencePropertyTag(false))
+	}
+
+	if len(p.SystemSharedLibs) > 0 {
+		propertySet.AddPropertyWithTag("system_shared_libs", p.SystemSharedLibs, builder.SdkMemberReferencePropertyTag(false))
+	}
 }

cc/cc.go

@@ -370,6 +370,15 @@ type linker interface {
 
 	nativeCoverage() bool
 	coverageOutputFilePath() android.OptionalPath
+
+	// Get the deps that have been explicitly specified in the properties.
+	// Only updates the
+	linkerSpecifiedDeps(specifiedDeps specifiedDeps) specifiedDeps
+}
+
+type specifiedDeps struct {
+	sharedLibs       []string
+	systemSharedLibs []string
 }
 
 type installer interface {

cc/library.go

@@ -817,6 +817,23 @@ func (library *libraryDecorator) linkerDeps(ctx DepsContext, deps Deps) Deps {
 	return deps
 }
 
+func (library *libraryDecorator) linkerSpecifiedDeps(specifiedDeps specifiedDeps) specifiedDeps {
+	specifiedDeps = library.baseLinker.linkerSpecifiedDeps(specifiedDeps)
+	var properties StaticOrSharedProperties
+	if library.static() {
+		properties = library.StaticProperties.Static
+	} else if library.shared() {
+		properties = library.SharedProperties.Shared
+	}
+
+	specifiedDeps.sharedLibs = append(specifiedDeps.sharedLibs, properties.Shared_libs...)
+	specifiedDeps.systemSharedLibs = append(specifiedDeps.systemSharedLibs, properties.System_shared_libs...)
+
+	specifiedDeps.sharedLibs = android.FirstUniqueStrings(specifiedDeps.sharedLibs)
+	specifiedDeps.systemSharedLibs = android.FirstUniqueStrings(specifiedDeps.systemSharedLibs)
+	return specifiedDeps
+}
+
 func (library *libraryDecorator) linkStatic(ctx ModuleContext,
 	flags Flags, deps PathDeps, objs Objects) android.Path {
 

cc/library_sdk_member.go

@@ -19,6 +19,7 @@ import (
 
 	"android/soong/android"
 	"github.com/google/blueprint"
+	"github.com/google/blueprint/proptools"
 )
 
 // This file contains support for using cc library modules within an sdk.
@@ -108,8 +109,11 @@ func (mt *librarySdkMemberType) AddPrebuiltModule(sdkModuleContext android.Modul
 }
 
 func (mt *librarySdkMemberType) FinalizeModule(sdkModuleContext android.ModuleContext, builder android.SnapshotBuilder, member android.SdkMember, bpModule android.BpModule) {
-	bpModule.AddProperty("stl", "none")
+	ccModule := (member.Variants()[0]).(*Module)
-	bpModule.AddProperty("system_shared_libs", []string{})
+	stl := ccModule.stl.Properties.Stl
+	if stl != nil {
+		bpModule.AddProperty("stl", proptools.String(stl))
+	}
 }
 
 func (mt *librarySdkMemberType) CreateVariantPropertiesStruct() android.SdkMemberProperties {
@@ -193,6 +197,14 @@ func addPossiblyArchSpecificProperties(sdkModuleContext android.ModuleContext, b
 		outputProperties.AddProperty("srcs", []string{nativeLibraryPath})
 	}
 
+	if len(libInfo.SharedLibs) > 0 {
+		outputProperties.AddPropertyWithTag("shared_libs", libInfo.SharedLibs, builder.SdkMemberReferencePropertyTag(false))
+	}
+
+	if len(libInfo.SystemSharedLibs) > 0 {
+		outputProperties.AddPropertyWithTag("system_shared_libs", libInfo.SystemSharedLibs, builder.SdkMemberReferencePropertyTag(false))
+	}
+
 	// Map from property name to the include dirs to add to the prebuilt module in the snapshot.
 	includeDirs := make(map[string][]string)
 
@@ -299,6 +311,16 @@ type nativeLibInfoProperties struct {
 	// This field is exported as its contents may not be arch specific.
 	ExportedFlags []string
 
+	// The set of shared libraries
+	//
+	// This field is exported as its contents may not be arch specific.
+	SharedLibs []string
+
+	// The set of system shared libraries
+	//
+	// This field is exported as its contents may not be arch specific.
+	SystemSharedLibs []string
+
 	// outputFile is not exported as it is always arch specific.
 	outputFile android.Path
 }
@@ -323,6 +345,13 @@ func (p *nativeLibInfoProperties) PopulateFromVariant(variant android.SdkAware)
 	p.exportedGeneratedIncludeDirs = exportedGeneratedIncludeDirs
 	p.ExportedSystemIncludeDirs = ccModule.ExportedSystemIncludeDirs()
 	p.ExportedFlags = ccModule.ExportedFlags()
+	if ccModule.linker != nil {
+		specifiedDeps := specifiedDeps{}
+		specifiedDeps = ccModule.linker.linkerSpecifiedDeps(specifiedDeps)
+
+		p.SharedLibs = specifiedDeps.sharedLibs
+		p.SystemSharedLibs = specifiedDeps.systemSharedLibs
+	}
 	p.exportedGeneratedHeaders = ccModule.ExportedGeneratedHeaders()
 }
 

cc/linker.go

@@ -490,6 +490,12 @@ func (linker *baseLinker) link(ctx ModuleContext,
 	panic(fmt.Errorf("baseLinker doesn't know how to link"))
 }
 
+func (linker *baseLinker) linkerSpecifiedDeps(specifiedDeps specifiedDeps) specifiedDeps {
+	specifiedDeps.sharedLibs = append(specifiedDeps.sharedLibs, linker.Properties.Shared_libs...)
+	specifiedDeps.systemSharedLibs = append(specifiedDeps.systemSharedLibs, linker.Properties.System_shared_libs...)
+	return specifiedDeps
+}
+
 // Injecting version symbols
 // Some host modules want a version number, but we don't want to rebuild it every time.  Optionally add a step
 // after linking that injects a constant placeholder with the current version number.

java/system_modules.go

@@ -255,5 +255,5 @@ func (mt *systemModulesSdkMemberType) BuildSnapshot(sdkModuleContext android.Mod
 
 	pbm := builder.AddPrebuiltModule(member, "java_system_modules_import")
 	// Add the references to the libraries that form the system module.
-	pbm.AddPropertyWithTag("libs", systemModule.properties.Libs, builder.SdkMemberReferencePropertyTag())
+	pbm.AddPropertyWithTag("libs", systemModule.properties.Libs, builder.SdkMemberReferencePropertyTag(true))
 }

sdk/cc_sdk_test.go

@@ -309,7 +309,6 @@ cc_prebuilt_library_shared {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_shared {
@@ -326,7 +325,6 @@ cc_prebuilt_library_shared {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 sdk_snapshot {
@@ -555,7 +553,6 @@ cc_prebuilt_library_shared {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_shared {
@@ -577,7 +574,6 @@ cc_prebuilt_library_shared {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 sdk_snapshot {
@@ -599,6 +595,189 @@ include/Test.h -> include/include/Test.h
 	)
 }
 
+func TestSnapshotWithCcSharedLibrarySharedLibs(t *testing.T) {
+	result := testSdkWithCc(t, `
+		sdk {
+			name: "mysdk",
+			native_shared_libs: [
+				"mynativelib",
+				"myothernativelib",
+				"mysystemnativelib",
+			],
+		}
+
+		cc_library {
+			name: "mysystemnativelib",
+			srcs: [
+				"Test.cpp",
+			],
+			system_shared_libs: [],
+			stl: "none",
+		}
+
+		cc_library_shared {
+			name: "myothernativelib",
+			srcs: [
+				"Test.cpp",
+			],
+			system_shared_libs: [
+				// A reference to a library that is not an sdk member. Uses libm as that
+				// is in the default set of modules available to this test and so is available
+				// both here and also when the generated Android.bp file is tested in
+				// CheckSnapshot(). This ensures that the system_shared_libs property correctly
+				// handles references to modules that are not sdk members.
+				"libm",
+			],
+			stl: "none",
+		}
+
+		cc_library {
+			name: "mynativelib",
+			srcs: [
+				"Test.cpp",
+			],
+			shared_libs: [
+				// A reference to another sdk member.
+				"myothernativelib",
+			],
+			target: {
+				android: {
+					shared: {
+						shared_libs: [
+							// A reference to a library that is not an sdk member. The libc library
+							// is used here to check that the shared_libs property is handled correctly
+							// in a similar way to how libm is used to check system_shared_libs above.
+							"libc",
+						],
+					},
+				},
+			},
+			system_shared_libs: [],
+			stl: "none",
+		}
+	`)
+
+	result.CheckSnapshot("mysdk", "",
+		checkAndroidBpContents(`
+// This is auto-generated. DO NOT EDIT.
+
+cc_prebuilt_library_shared {
+    name: "mysdk_mynativelib@current",
+    sdk_member_name: "mynativelib",
+    installable: false,
+    shared_libs: [
+        "mysdk_myothernativelib@current",
+        "libc",
+    ],
+    arch: {
+        arm64: {
+            srcs: ["arm64/lib/mynativelib.so"],
+        },
+        arm: {
+            srcs: ["arm/lib/mynativelib.so"],
+        },
+    },
+    stl: "none",
+}
+
+cc_prebuilt_library_shared {
+    name: "mynativelib",
+    prefer: false,
+    shared_libs: [
+        "myothernativelib",
+        "libc",
+    ],
+    arch: {
+        arm64: {
+            srcs: ["arm64/lib/mynativelib.so"],
+        },
+        arm: {
+            srcs: ["arm/lib/mynativelib.so"],
+        },
+    },
+    stl: "none",
+}
+
+cc_prebuilt_library_shared {
+    name: "mysdk_myothernativelib@current",
+    sdk_member_name: "myothernativelib",
+    installable: false,
+    system_shared_libs: ["libm"],
+    arch: {
+        arm64: {
+            srcs: ["arm64/lib/myothernativelib.so"],
+        },
+        arm: {
+            srcs: ["arm/lib/myothernativelib.so"],
+        },
+    },
+    stl: "none",
+}
+
+cc_prebuilt_library_shared {
+    name: "myothernativelib",
+    prefer: false,
+    system_shared_libs: ["libm"],
+    arch: {
+        arm64: {
+            srcs: ["arm64/lib/myothernativelib.so"],
+        },
+        arm: {
+            srcs: ["arm/lib/myothernativelib.so"],
+        },
+    },
+    stl: "none",
+}
+
+cc_prebuilt_library_shared {
+    name: "mysdk_mysystemnativelib@current",
+    sdk_member_name: "mysystemnativelib",
+    installable: false,
+    arch: {
+        arm64: {
+            srcs: ["arm64/lib/mysystemnativelib.so"],
+        },
+        arm: {
+            srcs: ["arm/lib/mysystemnativelib.so"],
+        },
+    },
+    stl: "none",
+}
+
+cc_prebuilt_library_shared {
+    name: "mysystemnativelib",
+    prefer: false,
+    arch: {
+        arm64: {
+            srcs: ["arm64/lib/mysystemnativelib.so"],
+        },
+        arm: {
+            srcs: ["arm/lib/mysystemnativelib.so"],
+        },
+    },
+    stl: "none",
+}
+
+sdk_snapshot {
+    name: "mysdk@current",
+    native_shared_libs: [
+        "mysdk_mynativelib@current",
+        "mysdk_myothernativelib@current",
+        "mysdk_mysystemnativelib@current",
+    ],
+}
+`),
+		checkAllCopyRules(`
+.intermediates/mynativelib/android_arm64_armv8-a_shared/mynativelib.so -> arm64/lib/mynativelib.so
+.intermediates/mynativelib/android_arm_armv7-a-neon_shared/mynativelib.so -> arm/lib/mynativelib.so
+.intermediates/myothernativelib/android_arm64_armv8-a_shared/myothernativelib.so -> arm64/lib/myothernativelib.so
+.intermediates/myothernativelib/android_arm_armv7-a-neon_shared/myothernativelib.so -> arm/lib/myothernativelib.so
+.intermediates/mysystemnativelib/android_arm64_armv8-a_shared/mysystemnativelib.so -> arm64/lib/mysystemnativelib.so
+.intermediates/mysystemnativelib/android_arm_armv7-a-neon_shared/mysystemnativelib.so -> arm/lib/mysystemnativelib.so
+`),
+	)
+}
+
 func TestHostSnapshotWithCcSharedLibrary(t *testing.T) {
 	// b/145598135 - Generating host snapshots for anything other than linux is not supported.
 	SkipIfNotLinux(t)
@@ -652,7 +831,6 @@ cc_prebuilt_library_shared {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_shared {
@@ -673,7 +851,6 @@ cc_prebuilt_library_shared {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 sdk_snapshot {
@@ -753,7 +930,6 @@ cc_prebuilt_library_shared {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_shared {
@@ -773,7 +949,6 @@ cc_prebuilt_library_shared {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 sdk_snapshot {
@@ -833,7 +1008,6 @@ cc_prebuilt_library_static {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_static {
@@ -851,7 +1025,6 @@ cc_prebuilt_library_static {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 module_exports_snapshot {
@@ -924,7 +1097,6 @@ cc_prebuilt_library_static {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_static {
@@ -944,7 +1116,6 @@ cc_prebuilt_library_static {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 module_exports_snapshot {
@@ -1020,7 +1191,6 @@ cc_prebuilt_library_static {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_static {
@@ -1036,7 +1206,6 @@ cc_prebuilt_library_static {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 module_exports_snapshot {
@@ -1084,7 +1253,6 @@ cc_prebuilt_library_headers {
     sdk_member_name: "mynativeheaders",
     export_include_dirs: ["include/include"],
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_headers {
@@ -1092,7 +1260,6 @@ cc_prebuilt_library_headers {
     prefer: false,
     export_include_dirs: ["include/include"],
     stl: "none",
-    system_shared_libs: [],
 }
 
 sdk_snapshot {
@@ -1139,7 +1306,6 @@ cc_prebuilt_library_headers {
     host_supported: true,
     export_include_dirs: ["include/include"],
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_headers {
@@ -1149,7 +1315,6 @@ cc_prebuilt_library_headers {
     host_supported: true,
     export_include_dirs: ["include/include"],
     stl: "none",
-    system_shared_libs: [],
 }
 
 sdk_snapshot {
@@ -1211,7 +1376,6 @@ cc_prebuilt_library_headers {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 cc_prebuilt_library_headers {
@@ -1228,7 +1392,6 @@ cc_prebuilt_library_headers {
         },
     },
     stl: "none",
-    system_shared_libs: [],
 }
 
 sdk_snapshot {

sdk/sdk.go

@@ -50,9 +50,6 @@ type sdk struct {
 	// list properties, e.g. java_libs.
 	dynamicMemberTypeListProperties interface{}
 
-	// The set of exported members.
-	exportedMembers map[string]struct{}
-
 	// Information about the OsType specific member variants associated with this variant.
 	//
 	// Set by OsType specific variants when their GenerateAndroidBuildActions is invoked
@@ -233,26 +230,19 @@ func (s *sdk) memberListProperties() []*sdkMemberListProperty {
 }
 
 func (s *sdk) getExportedMembers() map[string]struct{} {
-	if s.exportedMembers == nil {
+	// Collect all the exported members.
-		// Collect all the exported members.
+	exportedMembers := make(map[string]struct{})
-		s.exportedMembers = make(map[string]struct{})
 
-		for _, memberListProperty := range s.memberListProperties() {
+	for _, memberListProperty := range s.memberListProperties() {
-			names := memberListProperty.getter(s.dynamicMemberTypeListProperties)
+		names := memberListProperty.getter(s.dynamicMemberTypeListProperties)
 
-			// Every member specified explicitly in the properties is exported by the sdk.
+		// Every member specified explicitly in the properties is exported by the sdk.
-			for _, name := range names {
+		for _, name := range names {
-				s.exportedMembers[name] = struct{}{}
+			exportedMembers[name] = struct{}{}
-			}
 		}
 	}
 
-	return s.exportedMembers
+	return exportedMembers
-}
-
-func (s *sdk) isInternalMember(memberName string) bool {
-	_, ok := s.getExportedMembers()[memberName]
-	return !ok
 }
 
 func (s *sdk) snapshot() bool {

sdk/update.go

@@ -226,17 +226,23 @@ func versionedSdkMemberName(ctx android.ModuleContext, memberName string, versio
 // the contents (header files, stub libraries, etc) into the zip file.
 func (s *sdk) buildSnapshot(ctx android.ModuleContext, sdkVariants []*sdk) android.OutputPath {
 
-	exportedMembers := make(map[string]struct{})
+	allMembersByName := make(map[string]struct{})
+	exportedMembersByName := make(map[string]struct{})
 	var memberRefs []sdkMemberRef
 	for _, sdkVariant := range sdkVariants {
 		memberRefs = append(memberRefs, sdkVariant.memberRefs...)
 
+		// Record the names of all the members, both explicitly specified and implicitly
+		// included.
+		for _, memberRef := range sdkVariant.memberRefs {
+			allMembersByName[memberRef.variant.Name()] = struct{}{}
+		}
+
 		// Merge the exported member sets from all sdk variants.
 		for key, _ := range sdkVariant.getExportedMembers() {
-			exportedMembers[key] = struct{}{}
+			exportedMembersByName[key] = struct{}{}
 		}
 	}
-	s.exportedMembers = exportedMembers
 
 	snapshotDir := android.PathForModuleOut(ctx, "snapshot")
 
@@ -247,14 +253,16 @@ func (s *sdk) buildSnapshot(ctx android.ModuleContext, sdkVariants []*sdk) andro
 	}
 
 	builder := &snapshotBuilder{
-		ctx:             ctx,
+		ctx:                   ctx,
-		sdk:             s,
+		sdk:                   s,
-		version:         "current",
+		version:               "current",
-		snapshotDir:     snapshotDir.OutputPath,
+		snapshotDir:           snapshotDir.OutputPath,
-		copies:          make(map[string]string),
+		copies:                make(map[string]string),
-		filesToZip:      []android.Path{bp.path},
+		filesToZip:            []android.Path{bp.path},
-		bpFile:          bpFile,
+		bpFile:                bpFile,
-		prebuiltModules: make(map[string]*bpModule),
+		prebuiltModules:       make(map[string]*bpModule),
+		allMembersByName:      allMembersByName,
+		exportedMembersByName: exportedMembersByName,
 	}
 	s.builderForTests = builder
 
@@ -402,7 +410,7 @@ func (s *sdk) addMemberPropertiesToPropertySet(builder *snapshotBuilder, propert
 	for _, memberListProperty := range s.memberListProperties() {
 		names := memberListProperty.getter(dynamicMemberTypeListProperties)
 		if len(names) > 0 {
-			propertySet.AddProperty(memberListProperty.propertyName(), builder.versionedSdkMemberNames(names))
+			propertySet.AddProperty(memberListProperty.propertyName(), builder.versionedSdkMemberNames(names, false))
 		}
 	}
 }
@@ -415,7 +423,13 @@ type propertyTag struct {
 //
 // This will cause the references to be rewritten to a versioned reference in the version
 // specific instance of a snapshot module.
-var sdkMemberReferencePropertyTag = propertyTag{"sdkMemberReferencePropertyTag"}
+var requiredSdkMemberReferencePropertyTag = propertyTag{"requiredSdkMemberReferencePropertyTag"}
+
+// A BpPropertyTag to add to a property that contains references to other sdk members.
+//
+// This will cause the references to be rewritten to a versioned reference in the version
+// specific instance of a snapshot module.
+var optionalSdkMemberReferencePropertyTag = propertyTag{"optionalSdkMemberReferencePropertyTag"}
 
 // A BpPropertyTag that indicates the property should only be present in the versioned
 // module.
@@ -433,14 +447,15 @@ func (t unversionedToVersionedTransformation) transformModule(module *bpModule)
 	// Use a versioned name for the module but remember the original name for the
 	// snapshot.
 	name := module.getValue("name").(string)
-	module.setProperty("name", t.builder.versionedSdkMemberName(name))
+	module.setProperty("name", t.builder.versionedSdkMemberName(name, true))
 	module.insertAfter("name", "sdk_member_name", name)
 	return module
 }
 
 func (t unversionedToVersionedTransformation) transformProperty(name string, value interface{}, tag android.BpPropertyTag) (interface{}, android.BpPropertyTag) {
-	if tag == sdkMemberReferencePropertyTag {
+	if tag == requiredSdkMemberReferencePropertyTag || tag == optionalSdkMemberReferencePropertyTag {
-		return t.builder.versionedSdkMemberNames(value.([]string)), tag
+		required := tag == requiredSdkMemberReferencePropertyTag
+		return t.builder.versionedSdkMemberNames(value.([]string), required), tag
 	} else {
 		return value, tag
 	}
@@ -454,7 +469,7 @@ type unversionedTransformation struct {
 func (t unversionedTransformation) transformModule(module *bpModule) *bpModule {
 	// If the module is an internal member then use a unique name for it.
 	name := module.getValue("name").(string)
-	module.setProperty("name", t.builder.unversionedSdkMemberName(name))
+	module.setProperty("name", t.builder.unversionedSdkMemberName(name, true))
 
 	// Set prefer: false - this is not strictly required as that is the default.
 	module.insertAfter("name", "prefer", false)
@@ -463,8 +478,9 @@ func (t unversionedTransformation) transformModule(module *bpModule) *bpModule {
 }
 
 func (t unversionedTransformation) transformProperty(name string, value interface{}, tag android.BpPropertyTag) (interface{}, android.BpPropertyTag) {
-	if tag == sdkMemberReferencePropertyTag {
+	if tag == requiredSdkMemberReferencePropertyTag || tag == optionalSdkMemberReferencePropertyTag {
-		return t.builder.unversionedSdkMemberNames(value.([]string)), tag
+		required := tag == requiredSdkMemberReferencePropertyTag
+		return t.builder.unversionedSdkMemberNames(value.([]string), required), tag
 	} else if tag == sdkVersionedOnlyPropertyTag {
 		// The property is not allowed in the unversioned module so remove it.
 		return nil, nil
@@ -559,6 +575,12 @@ type snapshotBuilder struct {
 
 	prebuiltModules map[string]*bpModule
 	prebuiltOrder   []*bpModule
+
+	// The set of all members by name.
+	allMembersByName map[string]struct{}
+
+	// The set of exported members by name.
+	exportedMembersByName map[string]struct{}
 }
 
 func (s *snapshotBuilder) CopyToSnapshot(src android.Path, dest string) {
@@ -612,7 +634,7 @@ func (s *snapshotBuilder) AddPrebuiltModule(member android.SdkMember, moduleType
 
 	variant := member.Variants()[0]
 
-	if s.sdk.isInternalMember(name) {
+	if s.isInternalMember(name) {
 		// An internal member is only referenced from the sdk snapshot which is in the
 		// same package so can be marked as private.
 		m.AddProperty("visibility", []string{"//visibility:private"})
@@ -676,40 +698,66 @@ func addHostDeviceSupportedProperties(deviceSupported bool, hostSupported bool,
 	}
 }
 
-func (s *snapshotBuilder) SdkMemberReferencePropertyTag() android.BpPropertyTag {
+func (s *snapshotBuilder) SdkMemberReferencePropertyTag(required bool) android.BpPropertyTag {
-	return sdkMemberReferencePropertyTag
+	if required {
+		return requiredSdkMemberReferencePropertyTag
+	} else {
+		return optionalSdkMemberReferencePropertyTag
+	}
+}
+
+func (s *snapshotBuilder) OptionalSdkMemberReferencePropertyTag() android.BpPropertyTag {
+	return optionalSdkMemberReferencePropertyTag
 }
 
 // Get a versioned name appropriate for the SDK snapshot version being taken.
-func (s *snapshotBuilder) versionedSdkMemberName(unversionedName string) string {
+func (s *snapshotBuilder) versionedSdkMemberName(unversionedName string, required bool) string {
+	if _, ok := s.allMembersByName[unversionedName]; !ok {
+		if required {
+			s.ctx.ModuleErrorf("Required member reference %s is not a member of the sdk", unversionedName)
+		}
+		return unversionedName
+	}
 	return versionedSdkMemberName(s.ctx, unversionedName, s.version)
 }
 
-func (s *snapshotBuilder) versionedSdkMemberNames(members []string) []string {
+func (s *snapshotBuilder) versionedSdkMemberNames(members []string, required bool) []string {
 	var references []string = nil
 	for _, m := range members {
-		references = append(references, s.versionedSdkMemberName(m))
+		references = append(references, s.versionedSdkMemberName(m, required))
 	}
 	return references
 }
 
 // Get an internal name unique to the sdk.
-func (s *snapshotBuilder) unversionedSdkMemberName(unversionedName string) string {
+func (s *snapshotBuilder) unversionedSdkMemberName(unversionedName string, required bool) string {
-	if s.sdk.isInternalMember(unversionedName) {
+	if _, ok := s.allMembersByName[unversionedName]; !ok {
+		if required {
+			s.ctx.ModuleErrorf("Required member reference %s is not a member of the sdk", unversionedName)
+		}
+		return unversionedName
+	}
+
+	if s.isInternalMember(unversionedName) {
 		return s.ctx.ModuleName() + "_" + unversionedName
 	} else {
 		return unversionedName
 	}
 }
 
-func (s *snapshotBuilder) unversionedSdkMemberNames(members []string) []string {
+func (s *snapshotBuilder) unversionedSdkMemberNames(members []string, required bool) []string {
 	var references []string = nil
 	for _, m := range members {
-		references = append(references, s.unversionedSdkMemberName(m))
+		references = append(references, s.unversionedSdkMemberName(m, required))
 	}
 	return references
 }
 
+func (s *snapshotBuilder) isInternalMember(memberName string) bool {
+	_, ok := s.exportedMembersByName[memberName]
+	return !ok
+}
+
 type sdkMemberRef struct {
 	memberType android.SdkMemberType
 	variant    android.SdkAware