diff --git a/apps/Development/Android.mk b/apps/Development/Android.mk
index 39498d5..3db6cc3 100644
--- a/apps/Development/Android.mk
+++ b/apps/Development/Android.mk
@@ -5,6 +5,9 @@
 
 LOCAL_JAVA_LIBRARIES := android.test.runner.stubs telephony-common org.apache.http.legacy
 
+LOCAL_USES_LIBRARIES := android.test.runner
+LOCAL_OPTIONAL_USES_LIBRARIES := org.apache.http.legacy android.test.base android.test.mock
+
 LOCAL_SRC_FILES := $(call all-subdir-java-files) \
                 src/com/android/development/IRemoteService.aidl \
 
diff --git a/cmds/monkey/Android.bp b/cmds/monkey/Android.bp
index 192a66a..2b67032 100644
--- a/cmds/monkey/Android.bp
+++ b/cmds/monkey/Android.bp
@@ -17,16 +17,9 @@
     ],
 }
 
-java_library {
-    name: "monkeylib",
-    installable: true,
-    srcs: ["**/*.java"],
-    stem: "monkey",
-}
-
 //###############################################################
-cc_prebuilt_binary {
+java_binary {
     name: "monkey",
-    srcs: ["monkey"],
-    required: ["monkeylib"],
+    srcs: ["**/*.java"],
+    wrapper: "monkey",
 }
diff --git a/samples/AutofillKeyboard/lint-baseline.xml b/samples/AutofillKeyboard/lint-baseline.xml
index 9e60ad6..9ba91c5 100644
--- a/samples/AutofillKeyboard/lint-baseline.xml
+++ b/samples/AutofillKeyboard/lint-baseline.xml
@@ -36,6 +36,28 @@
 
     <issue
         id="NewApi"
+        message="Call requires API level R (current min is 29): `newStylesBuilder`"
+        errorLine1="        StylesBuilder stylesBuilder = UiVersions.newStylesBuilder();"
+        errorLine2="                                                 ~~~~~~~~~~~~~~~~">
+        <location
+            file="development/samples/AutofillKeyboard/src/com/example/android/autofillkeyboard/AutofillImeService.java"
+            line="229"
+            column="50"/>
+    </issue>
+
+    <issue
+        id="NewApi"
+        message="Call requires API level R (current min is 29): `newStyleBuilder`"
+        errorLine1="        Style style = InlineSuggestionUi.newStyleBuilder()"
+        errorLine2="                                         ~~~~~~~~~~~~~~~">
+        <location
+            file="development/samples/AutofillKeyboard/src/com/example/android/autofillkeyboard/AutofillImeService.java"
+            line="230"
+            column="42"/>
+    </issue>
+
+    <issue
+        id="NewApi"
         message="Call requires API level R (current min is 29): `new android.widget.inline.InlinePresentationSpec.Builder`"
         errorLine1="        presentationSpecs.add(new InlinePresentationSpec.Builder(new Size(100, getHeight()),"
         errorLine2="                              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~">
diff --git a/samples/UiAutomator/Android.bp b/samples/UiAutomator/Android.bp
new file mode 100644
index 0000000..3a92d57
--- /dev/null
+++ b/samples/UiAutomator/Android.bp
@@ -0,0 +1,29 @@
+//Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package {
+    // See: http://go/android-license-faq
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+java_library {
+    name: "uiautomator.samples",
+    installable: true,
+    srcs: ["src/**/*.java"],
+    libs: [
+        "uiautomator.core",
+        "android.test.base.stubs",
+    ],
+    static_libs: ["junit"],
+}
diff --git a/samples/UiAutomator/Android.mk b/samples/UiAutomator/Android.mk
deleted file mode 100644
index 5f4c593..0000000
--- a/samples/UiAutomator/Android.mk
+++ /dev/null
@@ -1,33 +0,0 @@
-#Copyright (C) 2012 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-local_target_dir := $(TARGET_OUT_DATA)/local/tmp
-LOCAL_PATH := $(call my-dir)
-
-include $(CLEAR_VARS)
-
-LOCAL_SRC_FILES := $(call all-java-files-under, src)
-
-LOCAL_MODULE_TAGS := optional
-
-LOCAL_MODULE := uiautomator.samples
-LOCAL_LICENSE_KINDS := SPDX-license-identifier-Apache-2.0
-LOCAL_LICENSE_CONDITIONS := notice
-
-LOCAL_JAVA_LIBRARIES := uiautomator.core android.test.base.stubs
-LOCAL_STATIC_JAVA_LIBRARIES := junit
-
-LOCAL_MODULE_PATH := $(local_target_dir)
-
-include $(BUILD_JAVA_LIBRARY)
diff --git a/scripts/Android.bp b/scripts/Android.bp
index aad32ca..a3fb2c7 100644
--- a/scripts/Android.bp
+++ b/scripts/Android.bp
@@ -51,8 +51,23 @@
         "example_crashes.py",
         "stack_core.py",
     ],
+    data: [
+        ":llvm-tools",
+    ],
     libs: ["python-symbol"],
-    test_suites: ["general-tests"],
+    version: {
+        py2: {
+            enabled: false,
+            embedded_launcher: false,
+        },
+        py3: {
+            enabled: true,
+            embedded_launcher: false,
+        },
+    },
+    test_options: {
+        unit_test: true,
+    },
 }
 
 python_test_host {
diff --git a/scripts/acov-llvm.py b/scripts/acov-llvm.py
index e175b19..063911f 100755
--- a/scripts/acov-llvm.py
+++ b/scripts/acov-llvm.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 #
-# Copyright (C) 202121 The Android Open Source Project
+# Copyright (C) 2021 The Android Open Source Project
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -32,11 +32,11 @@
 # or from all processes on the device:
 #   $ acov-llvm.py flush
 #
-# 4. pull coverage from device and generate coverage report
+# 4. Pull coverage from device and generate coverage report
 #   $ acov-llvm.py report -s <one-or-more-source-paths-in-$ANDROID_BUILD_TOP \
 #                         -b <one-or-more-binaries-in-$OUT> \
 # E.g.:
-# development/scripts/acov-llvm.py report \
+# acov-llvm.py report \
 #         -s bionic \
 #         -b \
 #         $OUT/symbols/apex/com.android.runtime/lib/bionic/libc.so \
@@ -60,7 +60,7 @@
 
 
 def _get_clang_revision():
-    regex = r'ClangDefaultVersion\s+= "(?P<rev>clang-r\d+)"'
+    regex = r'ClangDefaultVersion\s+= "(?P<rev>clang-r\d+[a-z]?)"'
     global_go = android_build_top() / 'build/soong/cc/config/global.go'
     with open(global_go) as infile:
         match = re.search(regex, infile.read())
@@ -84,14 +84,59 @@
         cmd, *args, **kwargs, check=True, stdout=subprocess.PIPE).stdout
 
 
+def adb(cmd, *args, **kwargs):
+    """call 'adb <cmd>' with logging."""
+    return check_output(['adb'] + cmd, *args, **kwargs)
+
+
+def adb_root(*args, **kwargs):
+    """call 'adb root' with logging."""
+    return adb(['root'], *args, **kwargs)
+
+
 def adb_shell(cmd, *args, **kwargs):
     """call 'adb shell <cmd>' with logging."""
-    return check_output(['adb', 'shell'] + cmd)
+    return adb(['shell'] + cmd, *args, **kwargs)
+
+
+def send_flush_signal(pids=None):
+
+    def _has_handler_sig37(pid):
+        try:
+            status = adb_shell(['cat', f'/proc/{pid}/status'],
+                               text=True,
+                               stderr=subprocess.DEVNULL)
+        except subprocess.CalledProcessError:
+            logging.warning(f'Process {pid} is no longer active')
+            return False
+
+        status = status.split('\n')
+        sigcgt = [
+            line.split(':\t')[1] for line in status if line.startswith('SigCgt')
+        ]
+        if not sigcgt:
+            logging.warning(f'Cannot find \'SigCgt:\' in /proc/{pid}/status')
+            return False
+        return int(sigcgt[0], base=16) & (1 << 36)
+
+    if not pids:
+        output = adb_shell(['ps', '-eo', 'pid'], text=True)
+        pids = [pid.strip() for pid in output.split()]
+        pids = pids[1:]  # ignore the column header
+    pids = [pid for pid in pids if _has_handler_sig37(pid)]
+
+    if not pids:
+        logging.warning(
+            f'couldn\'t find any process with handler for signal 37')
+
+    adb_shell(['kill', '-37'] + pids)
 
 
 def do_clean_device(args):
+    adb_root()
+
     logging.info('resetting coverage on device')
-    adb_shell(['kill', '-37', '-1'])
+    send_flush_signal()
 
     logging.info(
         f'sleeping for {FLUSH_SLEEP} seconds for coverage to be written')
@@ -102,16 +147,16 @@
 
 
 def do_flush(args):
+    adb_root()
+
     if args.procnames:
         pids = adb_shell(['pidof'] + args.procnames, text=True).split()
         logging.info(f'flushing coverage for pids: {pids}')
     else:
-        pids = ['-1']
+        pids = None
         logging.info('flushing coverage for all processes on device')
 
-    # TODO(pirama) Send signal 37 to only those processes that have a
-    # handler installed for it.  See b/149047976
-    adb_shell(['kill', '-37'] + pids)
+    send_flush_signal(pids)
 
     logging.info(
         f'sleeping for {FLUSH_SLEEP} seconds for coverage to be written')
@@ -119,6 +164,8 @@
 
 
 def do_report(args):
+    adb_root()
+
     temp_dir = tempfile.mkdtemp(
         prefix='covreport-', dir=os.environ.get('ANDROID_BUILD_TOP', None))
     logging.info(f'generating coverage report in {temp_dir}')
@@ -136,12 +183,16 @@
     object_flags = [args.binary[0]] + ['--object=' + b for b in args.binary[1:]]
     source_dirs = ['/proc/self/cwd/' + s for s in args.source_dir]
 
+    output_dir = f'{temp_dir}/html'
+
     check_output([
         str(LLVM_COV_PATH), 'show', f'--instr-profile={profdata}',
-        '--format=html', f'--output-dir={temp_dir}/html',
+        '--format=html', f'--output-dir={output_dir}',
         '--show-region-summary=false'
     ] + object_flags + source_dirs)
 
+    print(f'Coverage report data written in {output_dir}')
+
 
 def parse_args():
     parser = argparse.ArgumentParser()
diff --git a/scripts/cargo2android.py b/scripts/cargo2android.py
index 8557a6d..7c43aad 100755
--- a/scripts/cargo2android.py
+++ b/scripts/cargo2android.py
@@ -1280,7 +1280,10 @@
           print('Running:', cmd)
         with open(cargo_out, 'a') as out_file:
           out_file.write('### Running: ' + cmd + '\n')
-        os.system(cmd)
+        ret = os.system(cmd)
+        if ret != 0:
+          print('*** There was an error while running cargo.  ' +
+                'See the cargo.out file for details.')
     if added_workspace:  # restore original Cargo.toml
       with open(cargo_toml, 'w') as out_file:
         out_file.writelines(cargo_toml_lines)
diff --git a/scripts/symbol.py b/scripts/symbol.py
index 360a2cb..821da8e 100755
--- a/scripts/symbol.py
+++ b/scripts/symbol.py
@@ -24,6 +24,7 @@
 import os
 import platform
 import re
+import shutil
 import signal
 import subprocess
 import unittest
@@ -132,7 +133,9 @@
 
 
 def ToolPath(tool, toolchain=None):
-  """Return a fully-qualified path to the specified tool"""
+  """Return a fully-qualified path to the specified tool, or just the tool if it's on PATH """
+  if shutil.which(tool) is not None:
+      return tool
   if not toolchain:
     toolchain = FindToolchain()
   return os.path.join(toolchain, tool)
@@ -431,14 +434,14 @@
   if mangled_symbol in _SYMBOL_DEMANGLING_CACHE:
     return _SYMBOL_DEMANGLING_CACHE[mangled_symbol]
 
-  # TODO: Replace with llvm-cxxfilt when available.
   global _CACHED_CXX_FILT
   if not _CACHED_CXX_FILT:
-    os_name = platform.system().lower()
-    toolchains = glob.glob("%s/prebuilts/gcc/%s-*/host/*-linux-*/bin/*c++filt" %
-                           (ANDROID_BUILD_TOP, os_name))
+    toolchains = None
+    # TODO(b/187231324) do not hard-code prebuilt version number below
+    if os.path.exists('./clang-r416183b/bin/llvm-cxxfilt'):
+      toolchains = ["./clang-r416183b/bin/llvm-cxxfilt"]
     if not toolchains:
-      raise Exception("Could not find gcc c++filt tool")
+      raise Exception("Could not find llvm-cxxfilt tool")
     _CACHED_CXX_FILT = sorted(toolchains)[-1]
 
   cmd = [_CACHED_CXX_FILT]
diff --git a/tools/otagui/README.md b/tools/otagui/README.md
new file mode 100644
index 0000000..3d73f5e
--- /dev/null
+++ b/tools/otagui/README.md
@@ -0,0 +1,4 @@
+# README
+This is a GUI for generating OTA package, using OTA_from_target_files command.
+
+
diff --git a/vndk/snapshot/gen_buildfiles.py b/vndk/snapshot/gen_buildfiles.py
index f56187d..336a9f9 100644
--- a/vndk/snapshot/gen_buildfiles.py
+++ b/vndk/snapshot/gen_buildfiles.py
@@ -102,6 +102,8 @@
         self._snapshot_archs = utils.get_snapshot_archs(install_dir)
         self._root_bpfile = os.path.join(install_dir, utils.ROOT_BP_PATH)
         self._common_bpfile = os.path.join(install_dir, utils.COMMON_BP_PATH)
+        self._llndk = self._parse_lib_list(
+            os.path.basename(self._etc_paths['llndk.libraries.txt']))
         self._vndk_core = self._parse_lib_list(
             os.path.basename(self._etc_paths['vndkcore.libraries.txt']))
         self._vndk_sp = self._parse_lib_list(
@@ -232,15 +234,26 @@
             vndk_core_buildrules = self._gen_vndk_shared_prebuilts(
                 self._vndk_core[arch],
                 arch,
+                is_llndk=False,
                 is_vndk_sp=False,
                 is_binder32=is_binder32,
                 module_names=module_names)
             vndk_sp_buildrules = self._gen_vndk_shared_prebuilts(
                 self._vndk_sp[arch],
                 arch,
+                is_llndk=False,
                 is_vndk_sp=True,
                 is_binder32=is_binder32,
                 module_names=module_names)
+            include_llndk = self._vndk_version > 30
+            if include_llndk:
+                llndk_buildrules = self._gen_vndk_shared_prebuilts(
+                    self._llndk[arch],
+                    arch,
+                    is_llndk=True,
+                    is_vndk_sp=False,
+                    is_binder32=is_binder32,
+                    module_names=module_names)
 
             with open(bpfile_path, 'w') as bpfile:
                 bpfile.write(self._gen_autogen_msg('/'))
@@ -248,6 +261,9 @@
                 bpfile.write('\n'.join(vndk_core_buildrules))
                 bpfile.write('\n')
                 bpfile.write('\n'.join(vndk_sp_buildrules))
+                if include_llndk:
+                    bpfile.write('\n')
+                    bpfile.write('\n'.join(llndk_buildrules))
 
             variant_include_path = os.path.join(variant_path, 'include')
             include_path = os.path.join(self._install_dir, arch, 'include')
@@ -409,6 +425,7 @@
     def _gen_vndk_shared_prebuilts(self,
                                    prebuilts,
                                    arch,
+                                   is_llndk,
                                    is_vndk_sp,
                                    is_binder32,
                                    module_names):
@@ -417,6 +434,7 @@
         Args:
           prebuilts: list of VNDK shared prebuilts
           arch: string, VNDK snapshot arch (e.g. 'arm64')
+          is_llndk: bool, True if the prebuilts are LLNDK stubs
           is_vndk_sp: bool, True if prebuilts are VNDK_SP libs
           is_binder32: bool, True if binder interface is 32-bit
           module_names: dict, module names for given prebuilts
@@ -427,6 +445,7 @@
             bp_module = self._gen_vndk_shared_prebuilt(
                 prebuilt,
                 arch,
+                is_llndk=is_llndk,
                 is_vndk_sp=is_vndk_sp,
                 is_binder32=is_binder32,
                 module_names=module_names)
@@ -437,6 +456,7 @@
     def _gen_vndk_shared_prebuilt(self,
                                   prebuilt,
                                   arch,
+                                  is_llndk,
                                   is_vndk_sp,
                                   is_binder32,
                                   module_names):
@@ -446,6 +466,7 @@
         Args:
           prebuilt: string, name of prebuilt object
           arch: string, VNDK snapshot arch (e.g. 'arm64')
+          is_llndk: bool, True if prebuilt is a LLNDK stub
           is_vndk_sp: bool, True if prebuilt is a VNDK_SP lib
           is_binder32: bool, True if binder interface is 32-bit
           module_names: dict, module names for given prebuilts
@@ -571,19 +592,31 @@
 
         product_available = ''
         # if vndkproduct.libraries.txt is empty, make the VNDKs available to product by default.
-        if not self._vndk_product[arch] or prebuilt in self._vndk_product[arch]:
+        if not self._vndk_product[arch] or prebuilt in self._vndk_product[arch] or is_llndk:
             product_available = '{ind}product_available: true,\n'.format(
                 ind=self.INDENT)
 
-        vndk_sp = ''
-        if is_vndk_sp:
-            vndk_sp = '{ind}{ind}support_system_process: true,\n'.format(
-                ind=self.INDENT)
+        vndk_props = ''
+        if not is_llndk:
+            vndk_sp = ''
+            if is_vndk_sp:
+                vndk_sp = '{ind}{ind}support_system_process: true,\n'.format(
+                    ind=self.INDENT)
 
-        vndk_private = ''
-        if prebuilt in self._vndk_private[arch]:
-            vndk_private = '{ind}{ind}private: true,\n'.format(
-                ind=self.INDENT)
+            vndk_private = ''
+            if prebuilt in self._vndk_private[arch]:
+                vndk_private = '{ind}{ind}private: true,\n'.format(
+                    ind=self.INDENT)
+
+            vndk_props = ('{ind}vndk: {{\n'
+                          '{ind}{ind}enabled: true,\n'
+                          '{vndk_sp}'
+                          '{vndk_private}'
+                          '{ind}}},\n'.format(
+                              ind=self.INDENT,
+                              product_available=product_available,
+                              vndk_sp=vndk_sp,
+                              vndk_private=vndk_private))
 
         notice = get_notice_file(prebuilt)
         arch_props = get_arch_props(prebuilt, arch, src_paths)
@@ -599,11 +632,7 @@
                 '{binder32bit}'
                 '{ind}vendor_available: true,\n'
                 '{product_available}'
-                '{ind}vndk: {{\n'
-                '{ind}{ind}enabled: true,\n'
-                '{vndk_sp}'
-                '{vndk_private}'
-                '{ind}}},\n'
+                '{vndk_props}'
                 '{notice}'
                 '{arch_props}'
                 '}}\n'.format(
@@ -613,8 +642,7 @@
                     target_arch=arch,
                     binder32bit=binder32bit,
                     product_available=product_available,
-                    vndk_sp=vndk_sp,
-                    vndk_private=vndk_private,
+                    vndk_props=vndk_props,
                     notice=notice,
                     arch_props=arch_props))
 
diff --git a/vndk/tools/header-checker/utils/utils.py b/vndk/tools/header-checker/utils/utils.py
index 9256e18..e0fd5cf 100644
--- a/vndk/tools/header-checker/utils/utils.py
+++ b/vndk/tools/header-checker/utils/utils.py
@@ -2,6 +2,7 @@
 
 import gzip
 import os
+import re
 import shutil
 import subprocess
 import sys
@@ -177,9 +178,12 @@
     return os.path.join(product_out, 'lsdump_paths.txt')
 
 
-def _is_sanitizer_variation(variation):
-    """Check whether the variation is introduced by a sanitizer."""
-    return variation in {'asan', 'hwasan', 'tsan', 'intOverflow', 'cfi', 'scs'}
+def _get_module_variant_sort_key(suffix):
+    for variant in suffix.split('_'):
+        match = re.match(r'apex(\d+)$', variant)
+        if match:
+            return (int(match.group(1)), suffix)
+    return (-1, suffix)
 
 
 def _get_module_variant_dir_name(tag, vndk_version, arch_cpu_str):
@@ -232,13 +236,10 @@
                 if not variant.startswith(prefix):
                     continue
                 new_suffix = variant[len(prefix):]
-                # Skip if the suffix contains APEX variations.
-                new_variations = [x for x in new_suffix.split('_') if x]
-                if new_variations and not all(_is_sanitizer_variation(x)
-                                              for x in new_variations):
-                    continue
                 old_suffix = suffixes[libname].get(arch_cpu)
-                if not old_suffix or new_suffix > old_suffix:
+                if (not old_suffix or
+                        _get_module_variant_sort_key(new_suffix) >
+                        _get_module_variant_sort_key(old_suffix)):
                     lsdump_paths[libname][arch_cpu][tag] = path
                     suffixes[libname][arch_cpu] = new_suffix
     return lsdump_paths