diff --git a/android/allowlists/allowlists.go b/android/allowlists/allowlists.go
index 556e177..16e2328 100644
--- a/android/allowlists/allowlists.go
+++ b/android/allowlists/allowlists.go
@@ -582,6 +582,7 @@
 		"tagsoup",
 
 		// framework-minus-apex
+		"AndroidFrameworkLintChecker",
 		"ImmutabilityAnnotationProcessor",
 		"debian.mime.types.minimized",
 		"framework-javastream-protos",
@@ -676,6 +677,7 @@
 
 		// prebuilts
 		"prebuilt_stats-log-api-gen",
+		"prebuilt_aapt2",
 
 		// fastboot
 		"fastboot",
@@ -857,6 +859,7 @@
 		"kotlinx_coroutines",
 		"kotlinx_coroutines-device",
 		"kotlinx_coroutines-host",
+		"kotlinx_coroutines_android",
 
 		// for building com.android.neuralnetworks
 		"libimapper_stablec",
diff --git a/android/config.go b/android/config.go
index 8da97b2..04b43ac 100644
--- a/android/config.go
+++ b/android/config.go
@@ -167,7 +167,8 @@
 }
 
 // DisableHiddenApiChecks returns true if hiddenapi checks have been disabled.
-// For 'eng' target variant hiddenapi checks are disabled by default for performance optimisation,
+// For 'eng' target variant hiddenapi checks are disabled by default for performance optimisation
+// Hiddenapi checks are also disabled when RELEASE_DEFAULT_MODULE_BUILD_FROM_SOURCE is set to false
 // but can be enabled by setting environment variable ENABLE_HIDDENAPI_FLAGS=true.
 // For other target variants hiddenapi check are enabled by default but can be disabled by
 // setting environment variable UNSAFE_DISABLE_HIDDENAPI_FLAGS=true.
@@ -176,7 +177,8 @@
 func (c Config) DisableHiddenApiChecks() bool {
 	return !c.IsEnvTrue("ENABLE_HIDDENAPI_FLAGS") &&
 		(c.IsEnvTrue("UNSAFE_DISABLE_HIDDENAPI_FLAGS") ||
-			Bool(c.productVariables.Eng))
+			Bool(c.productVariables.Eng) ||
+			!c.ReleaseDefaultModuleBuildFromSource())
 }
 
 // MaxPageSizeSupported returns the max page size supported by the device. This
@@ -221,6 +223,13 @@
 	return c.config.productVariables.ReleaseAconfigFlagDefaultPermission
 }
 
+// The flag indicating behavior for the tree wrt building modules or using prebuilts
+// derived from RELEASE_DEFAULT_MODULE_BUILD_FROM_SOURCE
+func (c Config) ReleaseDefaultModuleBuildFromSource() bool {
+	return c.config.productVariables.ReleaseDefaultModuleBuildFromSource == nil ||
+		Bool(c.config.productVariables.ReleaseDefaultModuleBuildFromSource)
+}
+
 // A DeviceConfig object represents the configuration for a particular device
 // being built. For now there will only be one of these, but in the future there
 // may be multiple devices being built.
@@ -1002,12 +1011,18 @@
 
 func (c *config) PreviewApiLevels() []ApiLevel {
 	var levels []ApiLevel
-	for i, codename := range c.PlatformVersionActiveCodenames() {
+	i := 0
+	for _, codename := range c.PlatformVersionActiveCodenames() {
+		if codename == "REL" {
+			continue
+		}
+
 		levels = append(levels, ApiLevel{
 			value:     codename,
 			number:    i,
 			isPreview: true,
 		})
+		i++
 	}
 	return levels
 }
@@ -1442,7 +1457,7 @@
 }
 
 func (c *deviceConfig) VndkUseCoreVariant() bool {
-	return Bool(c.config.productVariables.VndkUseCoreVariant)
+	return Bool(c.config.productVariables.VndkUseCoreVariant) && Bool(c.config.productVariables.KeepVndk)
 }
 
 func (c *deviceConfig) SystemSdkVersions() []string {
diff --git a/android/variable.go b/android/variable.go
index 8882e80..006a77f 100644
--- a/android/variable.go
+++ b/android/variable.go
@@ -479,6 +479,8 @@
 
 	ReleaseAconfigFlagDefaultPermission string `json:",omitempty"`
 
+	ReleaseDefaultModuleBuildFromSource *bool `json:",omitempty"`
+
 	KeepVndk *bool `json:",omitempty"`
 
 	CheckVendorSeappViolations *bool `json:",omitempty"`
diff --git a/bp2build/symlink_forest.go b/bp2build/symlink_forest.go
index 966b94a..15a6df0 100644
--- a/bp2build/symlink_forest.go
+++ b/bp2build/symlink_forest.go
@@ -22,7 +22,6 @@
 	"regexp"
 	"sort"
 	"strconv"
-	"strings"
 	"sync"
 	"sync/atomic"
 
@@ -32,19 +31,12 @@
 )
 
 // A tree structure that describes what to do at each directory in the created
-// symlink tree. Currently it is used to enumerate which files/directories
+// symlink tree. Currently, it is used to enumerate which files/directories
 // should be excluded from symlinking. Each instance of "node" represents a file
 // or a directory. If excluded is true, then that file/directory should be
 // excluded from symlinking. Otherwise, the node is not excluded, but one of its
 // descendants is (otherwise the node in question would not exist)
 
-// This is a version int written to a file called symlink_forest_version at the root of the
-// symlink forest. If the version here does not match the version in the file, then we'll
-// clean the whole symlink forest and recreate it. This number can be bumped whenever there's
-// an incompatible change to the forest layout or a bug in incrementality that needs to be fixed
-// on machines that may still have the bug present in their forest.
-const symlinkForestVersion = 2
-
 type instructionsNode struct {
 	name     string
 	excluded bool // If false, this is just an intermediate node
@@ -193,7 +185,7 @@
 	srcPath := shared.JoinPath(topdir, src)
 	dstPath := shared.JoinPath(topdir, dst)
 
-	// Check if a symlink already exists.
+	// Check whether a symlink already exists.
 	if dstInfo, err := os.Lstat(dstPath); err != nil {
 		if !os.IsNotExist(err) {
 			fmt.Fprintf(os.Stderr, "Failed to lstat '%s': %s", dst, err)
@@ -240,44 +232,49 @@
 	return false
 }
 
-// maybeCleanSymlinkForest will remove the whole symlink forest directory if the version recorded
-// in the symlink_forest_version file is not equal to symlinkForestVersion.
-func maybeCleanSymlinkForest(topdir, forest string, verbose bool) error {
-	versionFilePath := shared.JoinPath(topdir, forest, "symlink_forest_version")
-	versionFileContents, err := os.ReadFile(versionFilePath)
-	if err != nil && !os.IsNotExist(err) {
-		return err
+// Returns the mtime of the soong_build binary to determine whether we should
+// force symlink_forest to re-execute
+func getSoongBuildMTime() (int64, error) {
+	binaryPath, err := os.Executable()
+	if err != nil {
+		return 0, err
 	}
-	versionFileString := strings.TrimSpace(string(versionFileContents))
-	symlinkForestVersionString := strconv.Itoa(symlinkForestVersion)
-	if err != nil || versionFileString != symlinkForestVersionString {
-		if verbose {
-			fmt.Fprintf(os.Stderr, "Old symlink_forest_version was %q, current is %q. Cleaning symlink forest before recreating...\n", versionFileString, symlinkForestVersionString)
-		}
-		err = os.RemoveAll(shared.JoinPath(topdir, forest))
-		if err != nil {
-			return err
-		}
+
+	info, err := os.Stat(binaryPath)
+	if err != nil {
+		return 0, err
 	}
-	return nil
+
+	return info.ModTime().UnixMilli(), nil
 }
 
-// maybeWriteVersionFile will write the symlink_forest_version file containing symlinkForestVersion
-// if it doesn't exist already. If it exists we know it must contain symlinkForestVersion because
-// we checked for that already in maybeCleanSymlinkForest
-func maybeWriteVersionFile(topdir, forest string) error {
-	versionFilePath := shared.JoinPath(topdir, forest, "symlink_forest_version")
-	_, err := os.Stat(versionFilePath)
+// cleanSymlinkForest will remove the whole symlink forest directory
+func cleanSymlinkForest(topdir, forest string) error {
+	return os.RemoveAll(shared.JoinPath(topdir, forest))
+}
+
+// This returns whether symlink forest should clean and replant symlinks.
+// It compares the mtime of this executable with the mtime of the last-run
+// soong_build binary. If they differ, then we should clean and replant.
+func shouldCleanSymlinkForest(topdir string, forest string, soongBuildMTime int64) (bool, error) {
+	mtimeFilePath := shared.JoinPath(topdir, forest, "soong_build_mtime")
+	mtimeFileContents, err := os.ReadFile(mtimeFilePath)
 	if err != nil {
-		if !os.IsNotExist(err) {
-			return err
-		}
-		err = os.WriteFile(versionFilePath, []byte(strconv.Itoa(symlinkForestVersion)+"\n"), 0666)
-		if err != nil {
-			return err
+		if os.IsNotExist(err) {
+			// This is likely the first time this has run with this functionality - clean away!
+			return true, nil
+		} else {
+			return false, err
 		}
 	}
-	return nil
+	return strconv.FormatInt(soongBuildMTime, 10) != string(mtimeFileContents), nil
+}
+
+func writeSoongBuildMTimeFile(topdir, forest string, mtime int64) error {
+	mtimeFilePath := shared.JoinPath(topdir, forest, "soong_build_mtime")
+	contents := []byte(strconv.FormatInt(mtime, 10))
+
+	return os.WriteFile(mtimeFilePath, contents, 0666)
 }
 
 // Recursively plants a symlink forest at forestDir. The symlink tree will
@@ -473,12 +470,26 @@
 		symlinkCount: atomic.Uint64{},
 	}
 
-	err := maybeCleanSymlinkForest(topdir, forest, verbose)
+	// Check whether soong_build has been modified since the last run
+	soongBuildMTime, err := getSoongBuildMTime()
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
 
+	shouldClean, err := shouldCleanSymlinkForest(topdir, forest, soongBuildMTime)
+
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	} else if shouldClean {
+		err = cleanSymlinkForest(topdir, forest)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+	}
+
 	instructions := instructionsFromExcludePathList(exclude)
 	go func() {
 		context.wg.Add(1)
@@ -491,11 +502,10 @@
 		deps = append(deps, dep)
 	}
 
-	err = maybeWriteVersionFile(topdir, forest)
+	err = writeSoongBuildMTimeFile(topdir, forest, soongBuildMTime)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
-
 	return deps, context.mkdirCount.Load(), context.symlinkCount.Load()
 }
diff --git a/cc/cc_test.go b/cc/cc_test.go
index f7eb8d2..794c5ee 100644
--- a/cc/cc_test.go
+++ b/cc/cc_test.go
@@ -677,6 +677,7 @@
 	config.TestProductVariables.DeviceVndkVersion = StringPtr("current")
 	config.TestProductVariables.Platform_vndk_version = StringPtr("29")
 	config.TestProductVariables.VndkUseCoreVariant = BoolPtr(true)
+	config.TestProductVariables.KeepVndk = BoolPtr(true)
 
 	setVndkMustUseVendorVariantListForTest(config, []string{"libvndk"})
 
diff --git a/cc/lto.go b/cc/lto.go
index df9ca0a..281b527 100644
--- a/cc/lto.go
+++ b/cc/lto.go
@@ -35,11 +35,11 @@
 // optimized at link time and may not be compatible with features that require
 // LTO, such as CFI.
 //
-// This file adds support to soong to automatically propogate LTO options to a
+// This file adds support to soong to automatically propagate LTO options to a
 // new variant of all static dependencies for each module with LTO enabled.
 
 type LTOProperties struct {
-	// Lto must violate capitialization style for acronyms so that it can be
+	// Lto must violate capitalization style for acronyms so that it can be
 	// referred to in blueprint files as "lto"
 	Lto struct {
 		Never *bool `android:"arch_variant"`
@@ -67,10 +67,12 @@
 }
 
 func (lto *lto) begin(ctx BaseModuleContext) {
-	// First, determine the module indepedent default LTO mode.
+	// First, determine the module independent default LTO mode.
 	ltoDefault := GlobalThinLTO(ctx)
 	if ctx.Config().IsEnvTrue("DISABLE_LTO") {
 		ltoDefault = false
+	} else if lto.Never() {
+		ltoDefault = false
 	} else if ctx.Host() {
 		// Performance and binary size are less important for host binaries.
 		ltoDefault = false
diff --git a/cc/lto_test.go b/cc/lto_test.go
index e0afd4a..7b7fe8c 100644
--- a/cc/lto_test.go
+++ b/cc/lto_test.go
@@ -23,11 +23,19 @@
 	"github.com/google/blueprint"
 )
 
-var NoGlobalThinLTOPreparer = android.GroupFixturePreparers(
+var LTOPreparer = android.GroupFixturePreparers(
 	prepareForCcTest,
-	android.FixtureModifyEnv(func(env map[string]string) {
-		env["GLOBAL_THINLTO"] = "false"
-	}))
+)
+
+func hasDep(result *android.TestResult, m android.Module, wantDep android.Module) bool {
+	var found bool
+	result.VisitDirectDeps(m, func(dep blueprint.Module) {
+		if dep == wantDep {
+			found = true
+		}
+	})
+	return found
+}
 
 func TestThinLtoDeps(t *testing.T) {
 	t.Parallel()
@@ -37,9 +45,6 @@
 		srcs: ["src.c"],
 		static_libs: ["foo", "lib_never_lto"],
 		shared_libs: ["bar"],
-		lto: {
-			thin: true,
-		}
 	}
 	cc_library_static {
 		name: "foo",
@@ -63,50 +68,40 @@
 	}
 `
 
-	result := NoGlobalThinLTOPreparer.RunTestWithBp(t, bp)
+	result := LTOPreparer.RunTestWithBp(t, bp)
 
 	libLto := result.ModuleForTests("lto_enabled", "android_arm64_armv8-a_shared").Module()
 
-	hasDep := func(m android.Module, wantDep android.Module) bool {
-		var found bool
-		result.VisitDirectDeps(m, func(dep blueprint.Module) {
-			if dep == wantDep {
-				found = true
-			}
-		})
-		return found
+	libFoo := result.ModuleForTests("foo", "android_arm64_armv8-a_static").Module()
+	if !hasDep(result, libLto, libFoo) {
+		t.Errorf("'lto_enabled' missing dependency on the default variant of 'foo'")
 	}
 
-	libFoo := result.ModuleForTests("foo", "android_arm64_armv8-a_static_lto-thin").Module()
-	if !hasDep(libLto, libFoo) {
-		t.Errorf("'lto_enabled' missing dependency on thin lto variant of 'foo'")
+	libBaz := result.ModuleForTests("baz", "android_arm64_armv8-a_static").Module()
+	if !hasDep(result, libFoo, libBaz) {
+		t.Errorf("'foo' missing dependency on the default variant of transitive dep 'baz'")
 	}
 
-	libBaz := result.ModuleForTests("baz", "android_arm64_armv8-a_static_lto-thin").Module()
-	if !hasDep(libFoo, libBaz) {
-		t.Errorf("'foo' missing dependency on thin lto variant of transitive dep 'baz'")
-	}
-
-	libNeverLto := result.ModuleForTests("lib_never_lto", "android_arm64_armv8-a_static_lto-thin").Module()
-	if !hasDep(libLto, libNeverLto) {
-		t.Errorf("'lto_enabled' missing dependency on NO-thin lto variant of 'lib_never_lto'")
+	libNeverLto := result.ModuleForTests("lib_never_lto", "android_arm64_armv8-a_static").Module()
+	if !hasDep(result, libLto, libNeverLto) {
+		t.Errorf("'lto_enabled' missing dependency on the default variant of 'lib_never_lto'")
 	}
 
 	libBar := result.ModuleForTests("bar", "android_arm64_armv8-a_shared").Module()
-	if !hasDep(libLto, libBar) {
-		t.Errorf("'lto_enabled' missing dependency on non-thin lto variant of 'bar'")
+	if !hasDep(result, libLto, libBar) {
+		t.Errorf("'lto_enabled' missing dependency on the default variant of 'bar'")
 	}
 
 	barVariants := result.ModuleVariantsForTests("bar")
 	for _, v := range barVariants {
-		if strings.Contains(v, "lto-thin") {
-			t.Errorf("Expected variants for 'bar' to not contain 'lto-thin', but found %q", v)
+		if strings.Contains(v, "lto-none") {
+			t.Errorf("Expected variants for 'bar' to not contain 'lto-none', but found %q", v)
 		}
 	}
 	quxVariants := result.ModuleVariantsForTests("qux")
 	for _, v := range quxVariants {
-		if strings.Contains(v, "lto-thin") {
-			t.Errorf("Expected variants for 'qux' to not contain 'lto-thin', but found %q", v)
+		if strings.Contains(v, "lto-none") {
+			t.Errorf("Expected variants for 'qux' to not contain 'lto-none', but found %q", v)
 		}
 	}
 }
@@ -141,28 +136,18 @@
 	}
 `
 
-	result := NoGlobalThinLTOPreparer.RunTestWithBp(t, bp)
+	result := LTOPreparer.RunTestWithBp(t, bp)
 
 	libRoot := result.ModuleForTests("root", "android_arm64_armv8-a_shared").Module()
 	libRootLtoNever := result.ModuleForTests("root_no_lto", "android_arm64_armv8-a_shared").Module()
 
-	hasDep := func(m android.Module, wantDep android.Module) bool {
-		var found bool
-		result.VisitDirectDeps(m, func(dep blueprint.Module) {
-			if dep == wantDep {
-				found = true
-			}
-		})
-		return found
-	}
-
 	libFoo := result.ModuleForTests("foo", "android_arm64_armv8-a_static")
-	if !hasDep(libRoot, libFoo.Module()) {
-		t.Errorf("'root' missing dependency on thin lto variant of 'foo'")
+	if !hasDep(result, libRoot, libFoo.Module()) {
+		t.Errorf("'root' missing dependency on the default variant of 'foo'")
 	}
 
-	if !hasDep(libRootLtoNever, libFoo.Module()) {
-		t.Errorf("'root_no_lto' missing dependency on thin lto variant of 'foo'")
+	if !hasDep(result, libRootLtoNever, libFoo.Module()) {
+		t.Errorf("'root_no_lto' missing dependency on the default variant of 'foo'")
 	}
 
 	libFooCFlags := libFoo.Rule("cc").Args["cFlags"]
@@ -170,9 +155,9 @@
 		t.Errorf("'foo' expected to have flags %q, but got %q", w, libFooCFlags)
 	}
 
-	libBaz := result.ModuleForTests("baz", "android_arm64_armv8-a_static_lto-thin")
-	if !hasDep(libFoo.Module(), libBaz.Module()) {
-		t.Errorf("'foo' missing dependency on thin lto variant of transitive dep 'baz'")
+	libBaz := result.ModuleForTests("baz", "android_arm64_armv8-a_static")
+	if !hasDep(result, libFoo.Module(), libBaz.Module()) {
+		t.Errorf("'foo' missing dependency on the default variant of transitive dep 'baz'")
 	}
 
 	libBazCFlags := libFoo.Rule("cc").Args["cFlags"]
@@ -199,7 +184,7 @@
 			},
 		},
 	}`
-	result := NoGlobalThinLTOPreparer.RunTestWithBp(t, bp)
+	result := LTOPreparer.RunTestWithBp(t, bp)
 
 	libFooWithLto := result.ModuleForTests("libfoo", "android_arm_armv7-a-neon_shared").Rule("ld")
 	libFooWithoutLto := result.ModuleForTests("libfoo", "android_arm64_armv8-a_shared").Rule("ld")
@@ -227,7 +212,7 @@
 		},
 	}`
 
-	result := NoGlobalThinLTOPreparer.RunTestWithBp(t, bp)
+	result := LTOPreparer.RunTestWithBp(t, bp)
 
 	libFoo := result.ModuleForTests("libfoo", "android_arm_armv7-a-neon_shared").Rule("ld")
 	libBar := result.ModuleForTests("runtime_libbar", "android_arm_armv7-a-neon_shared").Rule("ld")
diff --git a/cc/ndk_library.go b/cc/ndk_library.go
index 2064b1b..4936559 100644
--- a/cc/ndk_library.go
+++ b/cc/ndk_library.go
@@ -61,7 +61,7 @@
 			// because we don't want to spam the build output with "nothing
 			// changed" messages, so redirect output message to $out, and if
 			// changes were detected print the output and fail.
-			Command:     "$stgdiff $args --stg $in -o $out || (cat $out && false; echo 'Run $$ANDROID_BUILD_TOP/development/tools/ndk/update_ndk_abi.sh to update the ABI dumps.')",
+			Command:     "$stgdiff $args --stg $in -o $out || (cat $out && echo 'Run $$ANDROID_BUILD_TOP/development/tools/ndk/update_ndk_abi.sh to update the ABI dumps.' && false)",
 			CommandDeps: []string{"$stgdiff"},
 		}, "args")
 
diff --git a/cc/sanitize.go b/cc/sanitize.go
index 6329e97..6624d4b 100644
--- a/cc/sanitize.go
+++ b/cc/sanitize.go
@@ -86,7 +86,7 @@
 	memtagStackCommonFlags = []string{"-march=armv8-a+memtag", "-mllvm", "-dom-tree-reachability-max-bbs-to-explore=128"}
 
 	hostOnlySanitizeFlags   = []string{"-fno-sanitize-recover=all"}
-	deviceOnlySanitizeFlags = []string{"-fsanitize-trap=all", "-ftrap-function=abort"}
+	deviceOnlySanitizeFlags = []string{"-fsanitize-trap=all"}
 
 	noSanitizeLinkRuntimeFlag = "-fno-sanitize-link-runtime"
 )
diff --git a/genrule/allowlists.go b/genrule/allowlists.go
index 3e92706..9647a18 100644
--- a/genrule/allowlists.go
+++ b/genrule/allowlists.go
@@ -17,6 +17,7 @@
 var (
 	DepfileAllowList = []string{
 		"depfile_allowed_for_test",
+		"tflite_support_metadata_schema",
 		"tflite_support_spm_config",
 		"tflite_support_spm_encoder_config",
 		"gen_uwb_core_proto",
@@ -249,6 +250,13 @@
 		"ue_unittest_erofs_imgs",
 		"vts_vndk_abi_dump_zip",
 		"atest_integration_fake_src",
+		"VehicleServerProtoStub_cc@2.0-grpc-trout",
+		"VehicleServerProtoStub_cc@default-grpc",
+		"VehicleServerProtoStub_h@default-grpc",
+		"VehicleServerProtoStub_h@2.0-grpc-trout",
+		"chre_atoms_log.h",
+		"checkIn-service-stub-lite",
+		"seller-frontend-service-stub-lite",
 	}
 
 	SandboxingDenyPathList = []string{
diff --git a/java/androidmk.go b/java/androidmk.go
index b7e2d2f..97b303d 100644
--- a/java/androidmk.go
+++ b/java/androidmk.go
@@ -20,6 +20,8 @@
 	"strings"
 
 	"android/soong/android"
+
+	"github.com/google/blueprint/proptools"
 )
 
 func (library *Library) AndroidMkEntriesHostDex() android.AndroidMkEntries {
@@ -79,7 +81,7 @@
 	} else if !library.ApexModuleBase.AvailableFor(android.AvailableToPlatform) {
 		// Platform variant.  If not available for the platform, we don't need Make module.
 		entriesList = append(entriesList, android.AndroidMkEntries{Disabled: true})
-	} else if library.properties.Headers_only {
+	} else if proptools.Bool(library.properties.Headers_only) {
 		// If generating headers only then don't expose to Make.
 		entriesList = append(entriesList, android.AndroidMkEntries{Disabled: true})
 	} else {
diff --git a/java/base.go b/java/base.go
index ec98dfe..03198b5 100644
--- a/java/base.go
+++ b/java/base.go
@@ -194,7 +194,7 @@
 	Generated_srcjars []android.Path `android:"mutated"`
 
 	// If true, then only the headers are built and not the implementation jar.
-	Headers_only bool
+	Headers_only *bool
 }
 
 // Properties that are specific to device modules. Host module factories should not add these when
@@ -582,7 +582,7 @@
 
 func (j *Module) checkHeadersOnly(ctx android.ModuleContext) {
 	if _, ok := ctx.Module().(android.SdkContext); ok {
-		headersOnly := proptools.Bool(&j.properties.Headers_only)
+		headersOnly := proptools.Bool(j.properties.Headers_only)
 		installable := proptools.Bool(j.properties.Installable)
 
 		if headersOnly && installable {
@@ -1180,7 +1180,7 @@
 	flags.classpath = append(android.CopyOf(extraClasspathJars), flags.classpath...)
 
 	// If compiling headers then compile them and skip the rest
-	if j.properties.Headers_only {
+	if proptools.Bool(j.properties.Headers_only) {
 		if srcFiles.HasExt(".kt") {
 			ctx.ModuleErrorf("Compiling headers_only with .kt not supported")
 		}
diff --git a/java/robolectric.go b/java/robolectric.go
index 0041af4..af56339 100644
--- a/java/robolectric.go
+++ b/java/robolectric.go
@@ -34,7 +34,7 @@
 
 var robolectricDefaultLibs = []string{
 	"mockito-robolectric-prebuilt",
-	"truth-prebuilt",
+	"truth",
 	// TODO(ccross): this is not needed at link time
 	"junitxml",
 }
diff --git a/mk2rbc/mk2rbc.go b/mk2rbc/mk2rbc.go
index 8225df6..78ab771 100644
--- a/mk2rbc/mk2rbc.go
+++ b/mk2rbc/mk2rbc.go
@@ -635,6 +635,13 @@
 	case "+=":
 		asgn.flavor = asgnAppend
 	case "?=":
+		if _, ok := lhs.(*productConfigVariable); ok {
+			// Make sets all product configuration variables to empty strings before running product
+			// config makefiles. ?= will have no effect on a variable that has been assigned before,
+			// even if assigned to an empty string. So just skip emitting any code for this
+			// assignment.
+			return nil
+		}
 		asgn.flavor = asgnMaybeSet
 	default:
 		panic(fmt.Errorf("unexpected assignment type %s", a.Type))
@@ -941,6 +948,8 @@
 
 func (ctx *parseContext) handleInclude(v *mkparser.Directive) []starlarkNode {
 	loadAlways := v.Name[0] != '-'
+	v.Args.TrimRightSpaces()
+	v.Args.TrimLeftSpaces()
 	return ctx.handleSubConfig(v, ctx.parseMakeString(v, v.Args), loadAlways, func(im inheritedModule) starlarkNode {
 		return &includeNode{im, loadAlways}
 	})
diff --git a/mk2rbc/mk2rbc_test.go b/mk2rbc/mk2rbc_test.go
index 7e68026..0c4d213 100644
--- a/mk2rbc/mk2rbc_test.go
+++ b/mk2rbc/mk2rbc_test.go
@@ -193,6 +193,31 @@
 	},
 
 	{
+		desc:   "Include with trailing whitespace",
+		mkname: "product.mk",
+		in: `
+# has a trailing whitespace after cfg.mk
+include vendor/$(foo)/cfg.mk 
+`,
+		expected: `# has a trailing whitespace after cfg.mk
+load("//build/make/core:product_config.rbc", "rblf")
+load("//vendor/foo1:cfg.star|init", _cfg_init = "init")
+load("//vendor/bar/baz:cfg.star|init", _cfg1_init = "init")
+
+def init(g, handle):
+  cfg = rblf.cfg(handle)
+  _entry = {
+    "vendor/foo1/cfg.mk": ("vendor/foo1/cfg", _cfg_init),
+    "vendor/bar/baz/cfg.mk": ("vendor/bar/baz/cfg", _cfg1_init),
+  }.get("vendor/%s/cfg.mk" % _foo)
+  (_varmod, _varmod_init) = _entry if _entry else (None, None)
+  if not _varmod_init:
+    rblf.mkerror("product.mk", "Cannot find %s" % ("vendor/%s/cfg.mk" % _foo))
+  _varmod_init(g, handle)
+`,
+	},
+
+	{
 		desc:   "Synonymous inherited configurations",
 		mkname: "path/product.mk",
 		in: `
@@ -898,8 +923,6 @@
   cfg["PRODUCT_LIST2"] += ["a"]
   cfg["PRODUCT_LIST1"] += ["b"]
   cfg["PRODUCT_LIST2"] += ["b"]
-  if cfg.get("PRODUCT_LIST3") == None:
-    cfg["PRODUCT_LIST3"] = ["a"]
   cfg["PRODUCT_LIST1"] = ["c"]
   g.setdefault("PLATFORM_LIST", [])
   g["PLATFORM_LIST"] += ["x"]
@@ -941,9 +964,10 @@
 PRODUCT_LIST2 ?= a $(PRODUCT_LIST2)
 PRODUCT_LIST3 += a
 
-# Now doing them again should not have a setdefault because they've already been set
+# Now doing them again should not have a setdefault because they've already been set, except 2
+# which did not emit an assignment before
 PRODUCT_LIST1 = a $(PRODUCT_LIST1)
-PRODUCT_LIST2 ?= a $(PRODUCT_LIST2)
+PRODUCT_LIST2 = a $(PRODUCT_LIST2)
 PRODUCT_LIST3 += a
 `,
 		expected: `# All of these should have a setdefault because they're self-referential and not defined before
@@ -954,18 +978,15 @@
   rblf.setdefault(handle, "PRODUCT_LIST1")
   cfg["PRODUCT_LIST1"] = (["a"] +
       cfg.get("PRODUCT_LIST1", []))
-  if cfg.get("PRODUCT_LIST2") == None:
-    rblf.setdefault(handle, "PRODUCT_LIST2")
-    cfg["PRODUCT_LIST2"] = (["a"] +
-        cfg.get("PRODUCT_LIST2", []))
   rblf.setdefault(handle, "PRODUCT_LIST3")
   cfg["PRODUCT_LIST3"] += ["a"]
-  # Now doing them again should not have a setdefault because they've already been set
+  # Now doing them again should not have a setdefault because they've already been set, except 2
+  # which did not emit an assignment before
   cfg["PRODUCT_LIST1"] = (["a"] +
       cfg["PRODUCT_LIST1"])
-  if cfg.get("PRODUCT_LIST2") == None:
-    cfg["PRODUCT_LIST2"] = (["a"] +
-        cfg["PRODUCT_LIST2"])
+  rblf.setdefault(handle, "PRODUCT_LIST2")
+  cfg["PRODUCT_LIST2"] = (["a"] +
+      cfg.get("PRODUCT_LIST2", []))
   cfg["PRODUCT_LIST3"] += ["a"]
 `,
 	},
diff --git a/mk2rbc/variable.go b/mk2rbc/variable.go
index 0a26ed8..95e1f8e 100644
--- a/mk2rbc/variable.go
+++ b/mk2rbc/variable.go
@@ -109,14 +109,11 @@
 		}
 		emitAppend()
 	case asgnMaybeSet:
-		gctx.writef("if cfg.get(%q) == None:", pcv.nam)
-		gctx.indentLevel++
-		gctx.newLine()
-		if needsSetDefault {
-			emitSetDefault()
-		}
-		emitAssignment()
-		gctx.indentLevel--
+		// In mk2rbc.go we never emit a maybeSet assignment for product config variables, because
+		// they are set to empty strings before running product config.
+		panic("Should never get here")
+	default:
+		panic("Unknown assignment flavor")
 	}
 
 	gctx.setHasBeenAssigned(&pcv)
diff --git a/rust/config/arm64_device.go b/rust/config/arm64_device.go
index 564168b..6c021c7 100644
--- a/rust/config/arm64_device.go
+++ b/rust/config/arm64_device.go
@@ -54,6 +54,7 @@
 			strings.Join(rustFlags, " "))
 	}
 
+	ExportedVars.ExportStringListStaticVariable("DEVICE_ARM64_RUSTC_FLAGS", Arm64RustFlags)
 }
 
 type toolchainArm64 struct {
diff --git a/rust/config/global.go b/rust/config/global.go
index c37ac4e..4397d58 100644
--- a/rust/config/global.go
+++ b/rust/config/global.go
@@ -23,7 +23,7 @@
 
 var (
 	pctx         = android.NewPackageContext("android/soong/rust/config")
-	exportedVars = android.NewExportedVariables(pctx)
+	ExportedVars = android.NewExportedVariables(pctx)
 
 	RustDefaultVersion = "1.72.0"
 	RustDefaultBase    = "prebuilts/rust/"
@@ -111,9 +111,17 @@
 
 	pctx.StaticVariable("DeviceGlobalLinkFlags", strings.Join(deviceGlobalLinkFlags, " "))
 
-	exportedVars.ExportStringStaticVariable("RUST_DEFAULT_VERSION", RustDefaultVersion)
-	exportedVars.ExportStringListStaticVariable("GLOBAL_RUSTC_FLAGS", GlobalRustFlags)
-	exportedVars.ExportStringListStaticVariable("LINUX_HOST_GLOBAL_LINK_FLAGS", LinuxHostGlobalLinkFlags)
+	ExportedVars.ExportStringStaticVariable("RUST_DEFAULT_VERSION", RustDefaultVersion)
+	ExportedVars.ExportStringListStaticVariable("GLOBAL_RUSTC_FLAGS", GlobalRustFlags)
+	ExportedVars.ExportStringListStaticVariable("LINUX_HOST_GLOBAL_LINK_FLAGS", LinuxHostGlobalLinkFlags)
+
+	ExportedVars.ExportStringListStaticVariable("DEVICE_GLOBAL_RUSTC_FLAGS", deviceGlobalRustFlags)
+	ExportedVars.ExportStringListStaticVariable("DEVICE_GLOBAL_LINK_FLAGS",
+		android.RemoveListFromList(deviceGlobalLinkFlags, []string{
+			// The cc_config flags are retrieved from cc_toolchain by rust rules.
+			"${cc_config.DeviceGlobalLldflags}",
+			"-B${cc_config.ClangBin}",
+		}))
 }
 
 func HostPrebuiltTag(config android.Config) string {
@@ -137,5 +145,5 @@
 
 // BazelRustToolchainVars returns a string with
 func BazelRustToolchainVars(config android.Config) string {
-	return android.BazelToolchainVars(config, exportedVars)
+	return android.BazelToolchainVars(config, ExportedVars)
 }
diff --git a/tests/run_integration_tests.sh b/tests/run_integration_tests.sh
index 223baa4..8045591 100755
--- a/tests/run_integration_tests.sh
+++ b/tests/run_integration_tests.sh
@@ -10,6 +10,7 @@
 "$TOP/build/soong/tests/persistent_bazel_test.sh"
 "$TOP/build/soong/tests/soong_test.sh"
 "$TOP/build/soong/tests/stale_metrics_files_test.sh"
+"$TOP/build/soong/tests/symlink_forest_rerun_test.sh"
 "$TOP/prebuilts/build-tools/linux-x86/bin/py3-cmd" "$TOP/build/bazel/ci/rbc_dashboard.py" aosp_arm64-userdebug
 
 # The following tests build against the full source tree and don't rely on the
diff --git a/tests/symlink_forest_rerun_test.sh b/tests/symlink_forest_rerun_test.sh
new file mode 100755
index 0000000..74e779e
--- /dev/null
+++ b/tests/symlink_forest_rerun_test.sh
@@ -0,0 +1,43 @@
+#!/bin/bash -eu
+
+set -o pipefail
+
+# Tests that symlink forest will replant if soong_build has changed
+# Any change to the build system should trigger a rerun
+
+source "$(dirname "$0")/lib.sh"
+
+function test_symlink_forest_reruns {
+  setup
+
+  mkdir -p a
+  touch a/g.txt
+  cat > a/Android.bp <<'EOF'
+filegroup {
+    name: "g",
+    srcs: ["g.txt"],
+  }
+EOF
+
+  run_soong g
+
+  mtime=`cat out/soong/workspace/soong_build_mtime`
+  # rerun with no changes - ensure that it hasn't changed
+  run_soong g
+  newmtime=`cat out/soong/workspace/soong_build_mtime`
+  if [[ ! "$mtime" == "$mtime" ]]; then
+     fail "symlink forest reran when it shouldn't have"
+  fi
+
+  # change exit codes to force a soong_build rebuild.
+  sed -i 's/os.Exit(1)/os.Exit(2)/g' build/soong/bp2build/symlink_forest.go
+
+  run_soong g
+  newmtime=`cat out/soong/workspace/soong_build_mtime`
+  if [[ "$mtime" == "$newmtime" ]]; then
+     fail "symlink forest did not rerun when it should have"
+  fi
+
+}
+
+scan_and_run_tests