Merging 13 commit(s) from Chromium's toolchain-utils am: 1c417d433e am: 73b35a2885

Change-Id: I2546fc1ef608b262f5c9d8485156379ad78ee05d

36 files changed, 239 insertions, 133 deletions

diff --git a/afdo_metadata/kernel_afdo.json b/afdo_metadata/kernel_afdo.json
index 751af04c..24f40fe6 100644
--- a/afdo_metadata/kernel_afdo.json
+++ b/afdo_metadata/kernel_afdo.json
@@ -1,11 +1,17 @@
 {
     "chromeos-kernel-3_14": {
         "name": "R81-12607.58-1578524353"
-    }, 
+    },
     "chromeos-kernel-4_4": {
-        "name": "R82-12874.0-1581330812"
-    }, 
+        "name": "R82-12901.0-1582540582"
+    },
     "chromeos-kernel-3_18": {
-        "name": "R82-12861.0-1580725956"
+        "name": "R82-12901.0-1582540470"
+    },
+    "chromeos-kernel-4_14": {
+        "name": "R82-12896.0-1582540320"
+    },
+    "chromeos-kernel-4_19": {
+        "name": "R82-12898.0-1582540816"
     }
 }
\ No newline at end of file
diff --git a/binary_search_tool/binary_search_perforce.py b/binary_search_tool/binary_search_perforce.py
index 5065f709..f2a3c8d5 100755
--- a/binary_search_tool/binary_search_perforce.py
+++ b/binary_search_tool/binary_search_perforce.py
@@ -369,7 +369,7 @@ class P4BinarySearcher(VCSBinarySearcher):
       self.ce.RunCommand(command)
     command = 'cd %s' % self.checkout_dir
     command += '; g4 changes -c %s' % self.client_name
-    _, out, _ = self.ce.RunCommandWOUTPUOT(command)
+    _, out, _ = self.ce.RunCommandWOutput(command)
     changes = re.findall(r'Change (\d+)', out)
     if changes:
       command = 'cd %s' % self.checkout_dir
diff --git a/binary_search_tool/compiler_wrapper.py b/binary_search_tool/compiler_wrapper.py
index 8755ed42..0fd92c67 100755
--- a/binary_search_tool/compiler_wrapper.py
+++ b/binary_search_tool/compiler_wrapper.py
@@ -37,7 +37,7 @@ BISECT_DIR = os.environ.get('BISECT_DIR') or DEFAULT_BISECT_DIR
 def ProcessArgFile(arg_file):
   args = []
   # Read in entire file at once and parse as if in shell
-  with open(arg_file, 'rb') as f:
+  with open(arg_file, 'r', encoding='utf-8') as f:
     args.extend(shlex.split(f.read()))
 
   return args
diff --git a/binary_search_tool/test/binary_search_tool_test.py b/binary_search_tool/test/binary_search_tool_test.py
index ca9313b5..6f5b514e 100755
--- a/binary_search_tool/test/binary_search_tool_test.py
+++ b/binary_search_tool/test/binary_search_tool_test.py
@@ -202,7 +202,7 @@ class BisectingUtilsTest(unittest.TestCase):
       f.write('test123')
 
     bss = binary_search_state.MockBinarySearchState()
-    with self.assertRaises(binary_search_state.Error):
+    with self.assertRaises(OSError):
       bss.SaveState()
 
     with open(state_file, 'r', encoding='utf-8') as f:
diff --git a/buildbot_test_toolchains.py b/buildbot_test_toolchains.py
index 5f7c21d3..1609da49 100755
--- a/buildbot_test_toolchains.py
+++ b/buildbot_test_toolchains.py
@@ -204,23 +204,23 @@ class ToolchainComparator(object):
 
       # Now add vanilla to test file.
       official_image = """
-          vanilla_image {
-            chromeos_root: %s
-            build: %s
-            compiler: llvm
-          }
-          """ % (self._chromeos_root, vanilla_image)
+      vanilla_image {
+        chromeos_root: %s
+        build: %s
+        compiler: llvm
+      }
+      """ % (self._chromeos_root, vanilla_image)
       f.write(official_image)
 
       # Now add non-AFDO image to test file.
       if nonafdo_image:
         official_nonafdo_image = """
-          nonafdo_image {
-            chromeos_root: %s
-            build: %s
-            compiler: llvm
-          }
-          """ % (self._chromeos_root, nonafdo_image)
+        nonafdo_image {
+          chromeos_root: %s
+          build: %s
+          compiler: llvm
+        }
+        """ % (self._chromeos_root, nonafdo_image)
         f.write(official_nonafdo_image)
 
       label_string = '%s_trybot_image' % compiler_string
@@ -228,14 +228,14 @@ class ToolchainComparator(object):
       # Reuse autotest files from vanilla image for trybot images
       autotest_files = os.path.join('/tmp', vanilla_image, 'autotest_files')
       experiment_image = """
-          %s {
-            chromeos_root: %s
-            build: %s
-            autotest_path: %s
-            compiler: %s
-          }
-          """ % (label_string, self._chromeos_root, trybot_image,
-                 autotest_files, compiler_string)
+      %s {
+        chromeos_root: %s
+        build: %s
+        autotest_path: %s
+        compiler: %s
+      }
+      """ % (label_string, self._chromeos_root, trybot_image, autotest_files,
+             compiler_string)
       f.write(experiment_image)
 
     crosperf = os.path.join(TOOLCHAIN_DIR, 'crosperf', 'crosperf')
diff --git a/chromiumos_image_diff.py b/chromiumos_image_diff.py
index 66a54ccc..3d54100d 100755
--- a/chromiumos_image_diff.py
+++ b/chromiumos_image_diff.py
@@ -318,7 +318,7 @@ def Main(argv):
     for i, image_path in enumerate([options.image1, options.image2], start=1):
       image_path = os.path.realpath(image_path)
       if not os.path.isfile(image_path):
-        logger.getLogger().LogError('"{0}" is not a file.'.format(image_path))
+        logger.GetLogger().LogError('"{0}" is not a file.'.format(image_path))
         return 1
 
       chromeos_root = None
diff --git a/compiler_wrapper/bisect_flag.go b/compiler_wrapper/bisect_flag.go
index 8aec3e7e..f07d9a63 100644
--- a/compiler_wrapper/bisect_flag.go
+++ b/compiler_wrapper/bisect_flag.go
@@ -20,7 +20,7 @@ import sys
 def ExpandArgs(args, target):
 	for arg in args:
 		if arg[0] == '@':
-			with open(arg[1:], 'rb') as f:
+			with open(arg[1:], 'r', encoding='utf-8') as f:
 				ExpandArgs(shlex.split(f.read()), target)
 		else:
 			target.append(arg)
@@ -64,7 +64,7 @@ func calcBisectCommand(env env, cfg *config, bisectStage string, compilerCmd *co
 	return &command{
 		Path: "/usr/bin/env",
 		Args: append([]string{
-			"python",
+			"python3",
 			"-c",
 			bisectPythonCommand,
 			bisectStage,
diff --git a/compiler_wrapper/bisect_flag_test.go b/compiler_wrapper/bisect_flag_test.go
index 5c4c82d6..cc203a0f 100644
--- a/compiler_wrapper/bisect_flag_test.go
+++ b/compiler_wrapper/bisect_flag_test.go
@@ -56,7 +56,7 @@ func TestCallBisectDriverWithCCache(t *testing.T) {
 		if err := verifyPath(cmd, "/usr/bin/env"); err != nil {
 			t.Error(err)
 		}
-		if err := verifyArgOrder(cmd, "python", "/usr/bin/ccache"); err != nil {
+		if err := verifyArgOrder(cmd, "python3", "/usr/bin/ccache"); err != nil {
 			t.Error(err)
 		}
 		if err := verifyEnvUpdate(cmd, "CCACHE_DIR=.*"); err != nil {
@@ -138,7 +138,7 @@ func withBisectTestContext(t *testing.T, work func(ctx *testContext)) {
 			if err := verifyPath(cmd, "/usr/bin/env"); err != nil {
 				return err
 			}
-			if cmd.Args[0] != "python" {
+			if cmd.Args[0] != "python3" {
 				return fmt.Errorf("expected a call to python. Got: %s", cmd.Args[0])
 			}
 			if cmd.Args[1] != "-c" {
diff --git a/compiler_wrapper/compiler_wrapper.go b/compiler_wrapper/compiler_wrapper.go
index c614b99f..11fd8199 100644
--- a/compiler_wrapper/compiler_wrapper.go
+++ b/compiler_wrapper/compiler_wrapper.go
@@ -108,14 +108,14 @@ func callCompilerInternal(env env, cfg *config, inputCmd *command) (exitCode int
 	}
 	rusageLogfileName := getRusageLogFilename(env)
 	bisectStage := getBisectStage(env)
-	if shouldForceDisableWError(env) {
+	if newWarningsDir, ok := getNewWarningsDir(env, cfg); ok {
 		if rusageLogfileName != "" {
 			return 0, newUserErrorf("GETRUSAGE is meaningless with FORCE_DISABLE_WERROR")
 		}
 		if bisectStage != "" {
 			return 0, newUserErrorf("BISECT_STAGE is meaningless with FORCE_DISABLE_WERROR")
 		}
-		return doubleBuildWithWNoError(env, cfg, compilerCmd)
+		return doubleBuildWithWNoError(env, cfg, newWarningsDir, compilerCmd)
 	}
 	if shouldCompileWithFallback(env) {
 		if rusageLogfileName != "" {
diff --git a/compiler_wrapper/config.go b/compiler_wrapper/config.go
index 5f389684..70c27f06 100644
--- a/compiler_wrapper/config.go
+++ b/compiler_wrapper/config.go
@@ -14,6 +14,8 @@ type config struct {
 	isAndroidWrapper bool
 	// Whether to use ccache.
 	useCCache bool
+	// Whether llvmNext wrapper.
+	useLlvmNext bool
 	// Flags to add to gcc and clang.
 	commonFlags []string
 	// Flags to add to gcc only.
@@ -83,6 +85,7 @@ func getConfig(configName string, useCCache bool, useLlvmNext bool, version stri
 		return nil, newErrorwithSourceLocf("unknown config name: %s", configName)
 	}
 	cfg.useCCache = useCCache
+	cfg.useLlvmNext = useLlvmNext
 	if useLlvmNext {
 		cfg.clangFlags = append(cfg.clangFlags, llvmNextFlags...)
 	}
@@ -208,5 +211,5 @@ var androidConfig = &config{
 	gccFlags:         []string{},
 	clangFlags:       []string{},
 	clangPostFlags:   []string{},
-	newWarningsDir:   "/tmp/fatal_clang_warnings",
+	newWarningsDir:   "",
 }
diff --git a/compiler_wrapper/disable_werror_flag.go b/compiler_wrapper/disable_werror_flag.go
index 864397dd..0d68d560 100644
--- a/compiler_wrapper/disable_werror_flag.go
+++ b/compiler_wrapper/disable_werror_flag.go
@@ -9,16 +9,39 @@ import (
 	"encoding/json"
 	"io/ioutil"
 	"os"
+	"path"
 	"strings"
 	"syscall"
 )
 
-func shouldForceDisableWError(env env) bool {
-	value, _ := env.getenv("FORCE_DISABLE_WERROR")
-	return value != ""
+func getNewWarningsDir(env env, cfg *config) (dirName string, ok bool) {
+	if cfg.isAndroidWrapper {
+		if cfg.useLlvmNext {
+			value, _ := env.getenv("OUT_DIR")
+			if value != "" {
+				return path.Join(value, "warnings_reports"), true
+			}
+		}
+	} else {
+		value, _ := env.getenv("FORCE_DISABLE_WERROR")
+		if value != "" {
+			return cfg.newWarningsDir, true
+		}
+	}
+	return "", false
+}
+
+func disableWerrorFlags(originalArgs []string) []string {
+	noErrors := []string{"-Wno-error"}
+	for _, flag := range originalArgs {
+		if strings.HasPrefix(flag, "-Werror=") {
+			noErrors = append(noErrors, strings.Replace(flag, "-Werror", "-Wno-error", 1))
+		}
+	}
+	return noErrors
 }
 
-func doubleBuildWithWNoError(env env, cfg *config, originalCmd *command) (exitCode int, err error) {
+func doubleBuildWithWNoError(env env, cfg *config, newWarningsDir string, originalCmd *command) (exitCode int, err error) {
 	originalStdoutBuffer := &bytes.Buffer{}
 	originalStderrBuffer := &bytes.Buffer{}
 	// TODO: This is a bug in the old wrapper that it drops the ccache path
@@ -44,7 +67,7 @@ func doubleBuildWithWNoError(env env, cfg *config, originalCmd *command) (exitCo
 	retryStderrBuffer := &bytes.Buffer{}
 	retryCommand := &command{
 		Path:       originalCmd.Path,
-		Args:       append(originalCmd.Args, "-Wno-error"),
+		Args:       append(originalCmd.Args, disableWerrorFlags(originalCmd.Args)...),
 		EnvUpdates: originalCmd.EnvUpdates,
 	}
 	retryExitCode, err := wrapSubprocessErrorWithSourceLoc(retryCommand,
@@ -73,8 +96,8 @@ func doubleBuildWithWNoError(env env, cfg *config, originalCmd *command) (exitCo
 	defer syscall.Umask(oldMask)
 
 	// Allow root and regular users to write to this without issue.
-	if err := os.MkdirAll(cfg.newWarningsDir, 0777); err != nil {
-		return 0, wrapErrorwithSourceLocf(err, "error creating warnings directory %s", cfg.newWarningsDir)
+	if err := os.MkdirAll(newWarningsDir, 0777); err != nil {
+		return 0, wrapErrorwithSourceLocf(err, "error creating warnings directory %s", newWarningsDir)
 	}
 
 	// Have some tag to show that files aren't fully written. It would be sad if
@@ -85,7 +108,7 @@ func doubleBuildWithWNoError(env env, cfg *config, originalCmd *command) (exitCo
 	// Coming up with a consistent name for this is difficult (compiler command's
 	// SHA can clash in the case of identically named files in different
 	// directories, or similar); let's use a random one.
-	tmpFile, err := ioutil.TempFile(cfg.newWarningsDir, "warnings_report*.json"+incompleteSuffix)
+	tmpFile, err := ioutil.TempFile(newWarningsDir, "warnings_report*.json"+incompleteSuffix)
 	if err != nil {
 		return 0, wrapErrorwithSourceLocf(err, "error creating warnings file")
 	}
diff --git a/compiler_wrapper/disable_werror_flag_test.go b/compiler_wrapper/disable_werror_flag_test.go
index fb25d193..eb907e6b 100644
--- a/compiler_wrapper/disable_werror_flag_test.go
+++ b/compiler_wrapper/disable_werror_flag_test.go
@@ -11,6 +11,7 @@ import (
 	"io"
 	"io/ioutil"
 	"os"
+	"path"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -372,3 +373,46 @@ func TestDoubleBuildWerrorChmodsThingsAppropriately(t *testing.T) {
 		}
 	})
 }
+
+func TestAndroidGetNewWarningsDir(t *testing.T) {
+	withTestContext(t, func(ctx *testContext) {
+		outDir := "/foo/bar"
+		expectedDir := path.Join(outDir, "warnings_reports")
+
+		ctx.env = []string{"OUT_DIR=" + outDir}
+		ctx.cfg.isAndroidWrapper = true
+
+		// Disable werror ON
+		ctx.cfg.useLlvmNext = true
+		dir, ok := getNewWarningsDir(ctx, ctx.cfg)
+		if !ok || dir != expectedDir {
+			t.Errorf("disable Werror not enabled for Android with useLlvmNext (dirName=%q ok=%t), expectedDir=%q", dir, ok, expectedDir)
+		}
+
+		// Disable werror OFF
+		ctx.cfg.useLlvmNext = false
+		dir, ok = getNewWarningsDir(ctx, ctx.cfg)
+		if ok || dir != "" {
+			t.Errorf("disable Werror incorrectly enabled for Android without useLlvmNext (dirName=%q ok=%t)", dir, ok)
+		}
+	})
+}
+
+func TestChromeOSGetNewWarningsDirOn(t *testing.T) {
+	withForceDisableWErrorTestContext(t, func(ctx *testContext) {
+		dir, ok := getNewWarningsDir(ctx, ctx.cfg)
+		if !ok || dir != ctx.cfg.newWarningsDir {
+			t.Errorf("disable Werror not enabled for ChromeOS with FORCE_DISABLE_WERROR set (dirName=%q ok=%t) expectedDir=%q", dir, ok, ctx.cfg.newWarningsDir)
+		}
+
+	})
+}
+
+func TestChromeOSGetNewWarningsDirOff(t *testing.T) {
+	withTestContext(t, func(ctx *testContext) {
+		dir, ok := getNewWarningsDir(ctx, ctx.cfg)
+		if ok || dir != "" {
+			t.Errorf("disable Werror incorrectly enabled for ChromeOS without FORCE_DISABLE_WERROR set (dirName=%q ok=%t)", dir, ok)
+		}
+	})
+}
diff --git a/compiler_wrapper/rusage_flag.go b/compiler_wrapper/rusage_flag.go
index 2a3768c1..690308b2 100644
--- a/compiler_wrapper/rusage_flag.go
+++ b/compiler_wrapper/rusage_flag.go
@@ -18,6 +18,26 @@ func getRusageLogFilename(env env) string {
 	return value
 }
 
+func lockFileExclusive(fd uintptr) error {
+	maxTries := 100
+	for i := 0; i < maxTries; i++ {
+		const seekSet = 0
+		err := syscall.FcntlFlock(fd, syscall.F_SETLKW, &syscall.Flock_t{
+			Type:   syscall.F_WRLCK,
+			Whence: seekSet,
+			Start:  0,
+			Len:    0,
+		})
+		if err == nil {
+			return nil
+		}
+		if err != syscall.EINTR {
+			return fmt.Errorf("locking file: %v", err)
+		}
+	}
+	return fmt.Errorf("locking file failed after %d tries", maxTries)
+}
+
 func logRusage(env env, logFileName string, compilerCmd *command) (exitCode int, err error) {
 	rusageBefore := syscall.Rusage{}
 	if err := syscall.Getrusage(syscall.RUSAGE_CHILDREN, &rusageBefore); err != nil {
@@ -49,21 +69,35 @@ func logRusage(env env, logFileName string, compilerCmd *command) (exitCode int,
 	if err := os.MkdirAll(filepath.Dir(logFileName), 0777); err != nil {
 		return 0, wrapErrorwithSourceLocf(err, "error creating rusage log directory %s", logFileName)
 	}
+
+	timeUnit := float64(time.Second)
+	data := fmt.Sprintf("%.5f : %.5f : %.5f : %d : %s : %s\n",
+		float64(elapsedRealTime)/timeUnit, float64(elapsedUserTime)/timeUnit, float64(elapsedSysTime)/timeUnit,
+		maxMemUsed, absCompilerPath,
+		strings.Join(append([]string{filepath.Base(absCompilerPath)}, compilerCmd.Args...), " "))
+
 	// Note: using file mode 0666 so that a root-created log is writable by others.
 	logFile, err := os.OpenFile(logFileName, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0666)
 	if err != nil {
-		return 0, wrapErrorwithSourceLocf(err, "error creating rusage logfile %s", logFileName)
+		return 0, wrapErrorwithSourceLocf(err, "creating rusage logfile %s", logFileName)
 	}
-	timeUnit := float64(time.Second)
-	if _, err := fmt.Fprintf(logFile, "%.5f : %.5f : %.5f : %d : %s : %s\n",
-		float64(elapsedRealTime)/timeUnit, float64(elapsedUserTime)/timeUnit, float64(elapsedSysTime)/timeUnit,
-		maxMemUsed, absCompilerPath,
-		strings.Join(append([]string{filepath.Base(absCompilerPath)}, compilerCmd.Args...), " ")); err != nil {
+
+	// O_APPEND's atomicity guarantees are only for writes up to a certain size. If we don't
+	// lock the file, we might end up with corrupted records.
+	//
+	// Note that Close()'ing the file releases all associated locks.
+	if err := lockFileExclusive(logFile.Fd()); err != nil {
 		_ = logFile.Close()
-		return 0, wrapErrorwithSourceLocf(err, "error writing rusage logfile %s", logFileName)
+		return 0, wrapErrorwithSourceLocf(err, "locking rusage logfile %s: %v", logFileName, err)
+	}
+
+	_, err = logFile.WriteString(data)
+	closeErr := logFile.Close()
+	if err != nil {
+		return 0, wrapErrorwithSourceLocf(err, "writing to rusage logfile %s: %v", logFileName, err)
 	}
-	if err := logFile.Close(); err != nil {
-		return 0, wrapErrorwithSourceLocf(err, "error closing rusage logfile %s", logFileName)
+	if closeErr != nil {
+		return 0, wrapErrorwithSourceLocf(err, "closing rusage logfile %s: %v", logFileName, closeErr)
 	}
 
 	return exitCode, nil
diff --git a/compiler_wrapper/testdata/android_golden/bisect.json b/compiler_wrapper/testdata/android_golden/bisect.json
index 25df7f17..a1ffc50b 100644
--- a/compiler_wrapper/testdata/android_golden/bisect.json
+++ b/compiler_wrapper/testdata/android_golden/bisect.json
@@ -18,9 +18,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "/user/home/ANDROID_BISECT",
             "/tmp/stable/clang.real",
@@ -53,9 +53,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/tmp/stable/clang.real",
@@ -91,9 +91,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/tmp/stable/clang.real",
diff --git a/compiler_wrapper/testdata/cros_clang_host_golden/bisect.json b/compiler_wrapper/testdata/cros_clang_host_golden/bisect.json
index 28adfee2..437cae52 100644
--- a/compiler_wrapper/testdata/cros_clang_host_golden/bisect.json
+++ b/compiler_wrapper/testdata/cros_clang_host_golden/bisect.json
@@ -18,9 +18,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "/tmp/sysroot_bisect",
             "/tmp/stable/clang",
@@ -67,9 +67,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/tmp/stable/clang",
@@ -119,9 +119,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/tmp/stable/clang",
diff --git a/compiler_wrapper/testdata/cros_clang_host_golden/force_disable_werror.json b/compiler_wrapper/testdata/cros_clang_host_golden/force_disable_werror.json
index 248fcb4b..2393e71a 100644
--- a/compiler_wrapper/testdata/cros_clang_host_golden/force_disable_werror.json
+++ b/compiler_wrapper/testdata/cros_clang_host_golden/force_disable_werror.json
@@ -94,7 +94,8 @@
             "-Wno-unknown-warning-option",
             "main.cc",
             "-Wno-implicit-int-float-conversion",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ]
         }
       }
@@ -159,7 +160,8 @@
             "-Wno-unknown-warning-option",
             "main.cc",
             "-Wno-implicit-int-float-conversion",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ]
         },
         "stdout": "somemessage",
diff --git a/compiler_wrapper/testdata/cros_hardened_golden/bisect.json b/compiler_wrapper/testdata/cros_hardened_golden/bisect.json
index b00f9740..a6ac7a19 100644
--- a/compiler_wrapper/testdata/cros_hardened_golden/bisect.json
+++ b/compiler_wrapper/testdata/cros_hardened_golden/bisect.json
@@ -18,9 +18,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "/tmp/sysroot_bisect",
             "/usr/bin/ccache",
@@ -81,9 +81,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/usr/bin/ccache",
@@ -147,9 +147,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/usr/bin/ccache",
diff --git a/compiler_wrapper/testdata/cros_hardened_golden/force_disable_werror.json b/compiler_wrapper/testdata/cros_hardened_golden/force_disable_werror.json
index f975f452..f796764a 100644
--- a/compiler_wrapper/testdata/cros_hardened_golden/force_disable_werror.json
+++ b/compiler_wrapper/testdata/cros_hardened_golden/force_disable_werror.json
@@ -136,7 +136,8 @@
             "-B../../bin",
             "-target",
             "x86_64-cros-linux-gnu",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ],
           "env_updates": [
             "CCACHE_BASEDIR=/usr/x86_64-cros-linux-gnu",
@@ -233,7 +234,8 @@
             "-B../../bin",
             "-target",
             "x86_64-cros-linux-gnu",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ],
           "env_updates": [
             "CCACHE_BASEDIR=/usr/x86_64-cros-linux-gnu",
diff --git a/compiler_wrapper/testdata/cros_hardened_llvmnext_golden/bisect.json b/compiler_wrapper/testdata/cros_hardened_llvmnext_golden/bisect.json
index b00f9740..a6ac7a19 100644
--- a/compiler_wrapper/testdata/cros_hardened_llvmnext_golden/bisect.json
+++ b/compiler_wrapper/testdata/cros_hardened_llvmnext_golden/bisect.json
@@ -18,9 +18,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "/tmp/sysroot_bisect",
             "/usr/bin/ccache",
@@ -81,9 +81,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/usr/bin/ccache",
@@ -147,9 +147,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/usr/bin/ccache",
diff --git a/compiler_wrapper/testdata/cros_hardened_llvmnext_golden/force_disable_werror.json b/compiler_wrapper/testdata/cros_hardened_llvmnext_golden/force_disable_werror.json
index f975f452..f796764a 100644
--- a/compiler_wrapper/testdata/cros_hardened_llvmnext_golden/force_disable_werror.json
+++ b/compiler_wrapper/testdata/cros_hardened_llvmnext_golden/force_disable_werror.json
@@ -136,7 +136,8 @@
             "-B../../bin",
             "-target",
             "x86_64-cros-linux-gnu",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ],
           "env_updates": [
             "CCACHE_BASEDIR=/usr/x86_64-cros-linux-gnu",
@@ -233,7 +234,8 @@
             "-B../../bin",
             "-target",
             "x86_64-cros-linux-gnu",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ],
           "env_updates": [
             "CCACHE_BASEDIR=/usr/x86_64-cros-linux-gnu",
diff --git a/compiler_wrapper/testdata/cros_hardened_noccache_golden/bisect.json b/compiler_wrapper/testdata/cros_hardened_noccache_golden/bisect.json
index 5075f843..ac9beb55 100644
--- a/compiler_wrapper/testdata/cros_hardened_noccache_golden/bisect.json
+++ b/compiler_wrapper/testdata/cros_hardened_noccache_golden/bisect.json
@@ -18,9 +18,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "/tmp/sysroot_bisect",
             "/usr/bin/clang",
@@ -76,9 +76,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/usr/bin/clang",
@@ -137,9 +137,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/usr/bin/clang",
diff --git a/compiler_wrapper/testdata/cros_hardened_noccache_golden/force_disable_werror.json b/compiler_wrapper/testdata/cros_hardened_noccache_golden/force_disable_werror.json
index 59dfb93e..078c05da 100644
--- a/compiler_wrapper/testdata/cros_hardened_noccache_golden/force_disable_werror.json
+++ b/compiler_wrapper/testdata/cros_hardened_noccache_golden/force_disable_werror.json
@@ -121,7 +121,8 @@
             "-B../../bin",
             "-target",
             "x86_64-cros-linux-gnu",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ]
         }
       }
@@ -204,7 +205,8 @@
             "-B../../bin",
             "-target",
             "x86_64-cros-linux-gnu",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ]
         },
         "stdout": "somemessage",
diff --git a/compiler_wrapper/testdata/cros_nonhardened_golden/bisect.json b/compiler_wrapper/testdata/cros_nonhardened_golden/bisect.json
index cb5dea01..22ba14c0 100644
--- a/compiler_wrapper/testdata/cros_nonhardened_golden/bisect.json
+++ b/compiler_wrapper/testdata/cros_nonhardened_golden/bisect.json
@@ -18,9 +18,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "/tmp/sysroot_bisect",
             "/usr/bin/ccache",
@@ -73,9 +73,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/usr/bin/ccache",
@@ -131,9 +131,9 @@
         "cmd": {
           "path": "/usr/bin/env",
           "args": [
-            "python",
+            "python3",
             "-c",
-            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'rb') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
+            "\nimport bisect_driver\nimport shlex\nimport sys\n\ndef ExpandArgs(args, target):\n\tfor arg in args:\n\t\tif arg[0] == '@':\n\t\t\twith open(arg[1:], 'r', encoding='utf-8') as f:\n\t\t\t\tExpandArgs(shlex.split(f.read()), target)\n\t\telse:\n\t\t\ttarget.append(arg)\n\treturn target\n\nstage = sys.argv[1]\ndir = sys.argv[2]\nexecargs = ExpandArgs(sys.argv[3:], [])\n\nsys.exit(bisect_driver.bisect_driver(stage, dir, execargs))\n",
             "someBisectStage",
             "someBisectDir",
             "/usr/bin/ccache",
diff --git a/compiler_wrapper/testdata/cros_nonhardened_golden/force_disable_werror.json b/compiler_wrapper/testdata/cros_nonhardened_golden/force_disable_werror.json
index 787ce95d..9787e8a6 100644
--- a/compiler_wrapper/testdata/cros_nonhardened_golden/force_disable_werror.json
+++ b/compiler_wrapper/testdata/cros_nonhardened_golden/force_disable_werror.json
@@ -112,7 +112,8 @@
             "-B../../bin",
             "-target",
             "x86_64-cros-linux-gnu",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ],
           "env_updates": [
             "CCACHE_BASEDIR=/usr/x86_64-cros-linux-gnu",
@@ -193,7 +194,8 @@
             "-B../../bin",
             "-target",
             "x86_64-cros-linux-gnu",
-            "-Wno-error"
+            "-Wno-error",
+            "-Wno-error=poison-system-directories"
           ],
           "env_updates": [
             "CCACHE_BASEDIR=/usr/x86_64-cros-linux-gnu",
diff --git a/cros_utils/buildbot_utils.py b/cros_utils/buildbot_utils.py
index a06abd26..428433db 100644
--- a/cros_utils/buildbot_utils.py
+++ b/cros_utils/buildbot_utils.py
@@ -27,7 +27,6 @@ TIME_OUT = 43200  # Decide the build is dead or will never finish
 
 class BuildbotTimeout(Exception):
   """Exception to throw when a buildbot operation timesout."""
-  pass
 
 
 def RunCommandInPath(path, cmd):
diff --git a/cros_utils/command_executer.py b/cros_utils/command_executer.py
index 39bff5ed..002aa754 100755
--- a/cros_utils/command_executer.py
+++ b/cros_utils/command_executer.py
@@ -240,10 +240,9 @@ class CommandExecuter(object):
     return command
 
   def WriteToTempShFile(self, contents):
-    # TODO(crbug.com/1048938): use encoding='utf-8' when all dependencies have
-    # migrated to python 3.
     with tempfile.NamedTemporaryFile(
-        'w', delete=False, prefix=os.uname()[1], suffix='.sh') as f:
+        'w', encoding='utf-8', delete=False, prefix=os.uname()[1],
+        suffix='.sh') as f:
       f.write('#!/bin/bash\n')
       f.write(contents)
       f.flush()
@@ -367,10 +366,9 @@ class CommandExecuter(object):
     if self.logger:
       self.logger.LogCmd(command, print_to_console=print_to_console)
 
-    # TODO(crbug.com/1048938): use encoding='utf-8' when all dependencies have
-    # migrated to python 3.
     with tempfile.NamedTemporaryFile(
         'w',
+        encoding='utf-8',
         delete=False,
         dir=os.path.join(chromeos_root, 'src/scripts'),
         suffix='.sh',
diff --git a/cros_utils/device_setup_utils_unittest.py b/cros_utils/device_setup_utils_unittest.py
index 63f9bf66..12a70811 100755
--- a/cros_utils/device_setup_utils_unittest.py
+++ b/cros_utils/device_setup_utils_unittest.py
@@ -14,10 +14,9 @@ import time
 import unittest
 from unittest import mock
 
-from device_setup_utils import DutWrapper
-
 from cros_utils import command_executer
 from cros_utils import logger
+from cros_utils.device_setup_utils import DutWrapper
 
 BIG_LITTLE_CPUINFO = """processor       : 0
 model name      : ARMv8 Processor rev 4 (v8l)
diff --git a/cros_utils/logger.py b/cros_utils/logger.py
index 4cc4618e..e304fe12 100644
--- a/cros_utils/logger.py
+++ b/cros_utils/logger.py
@@ -207,7 +207,6 @@ class MockLogger(object):
   def __init__(self, *_args, **_kwargs):
     self.stdout = sys.stdout
     self.stderr = sys.stderr
-    return None
 
   def _AddSuffix(self, basename, suffix):
     return '%s%s' % (basename, suffix)
diff --git a/cros_utils/misc.py b/cros_utils/misc.py
index 246767f0..b4beb60c 100644
--- a/cros_utils/misc.py
+++ b/cros_utils/misc.py
@@ -462,7 +462,7 @@ def ApplyGerritPatches(chromeos_root, gerrit_patch_string,
   sys.path.append(os.path.join(chromeos_root, 'chromite'))
   # Imports below are ok after modifying path to add chromite.
   # Pylint cannot detect that and complains.
-  # pylint: disable=import-error
+  # pylint: disable=import-error, import-outside-toplevel
   from lib import git
   from lib import gerrit
   manifest = git.ManifestCheckout(chromeos_root)
diff --git a/cros_utils/tabulator.py b/cros_utils/tabulator.py
index 300c2d79..5029ceee 100644
--- a/cros_utils/tabulator.py
+++ b/cros_utils/tabulator.py
@@ -318,7 +318,7 @@ class SamplesTableGenerator(TableGenerator):
               v.append(None)
               run_fail += 1
           one_tuple = ((run_pass, run_fail), v)
-          if iterations != 0 and iterations != run_pass + run_fail:
+          if iterations not in (0, run_pass + run_fail):
             raise ValueError('Iterations of each benchmark run ' \
                              'are not the same')
           iterations = run_pass + run_fail
@@ -358,7 +358,7 @@ class SamplesTableGenerator(TableGenerator):
             # Accumulate each run result to composite benchmark run
             # If any run fails, then we set this run for composite benchmark
             # to None so that we know it fails.
-            if bench_runs[index] and row[label_index][index] != None:
+            if bench_runs[index] and row[label_index][index] is not None:
               row[label_index][index] += bench_runs[index]
             else:
               row[label_index][index] = None
@@ -557,12 +557,10 @@ class AmeanResult(StringMeanResult):
 
 class RawResult(Result):
   """Raw result."""
-  pass
 
 
 class IterationResult(Result):
   """Iteration result."""
-  pass
 
 
 class MinResult(Result):
diff --git a/crosperf/experiment_factory.py b/crosperf/experiment_factory.py
index 4527db5f..3b1ed614 100644
--- a/crosperf/experiment_factory.py
+++ b/crosperf/experiment_factory.py
@@ -229,8 +229,8 @@ class ExperimentFactory(object):
 
       iterations = benchmark_settings.GetField('iterations')
       if cwp_dso:
-        if cwp_dso_iterations != 0 and iterations != cwp_dso_iterations:
-          raise RuntimeError('Iterations of each benchmark run are not the ' \
+        if cwp_dso_iterations not in (0, iterations):
+          raise RuntimeError('Iterations of each benchmark run are not the '
                              'same')
         cwp_dso_iterations = iterations
 
diff --git a/crosperf/experiment_file.py b/crosperf/experiment_file.py
index 1d89edad..d2831bda 100644
--- a/crosperf/experiment_file.py
+++ b/crosperf/experiment_file.py
@@ -95,7 +95,8 @@ class ExperimentFile(object):
 
       if not line:
         continue
-      elif ExperimentFile._FIELD_VALUE_RE.match(line):
+
+      if ExperimentFile._FIELD_VALUE_RE.match(line):
         field = self._ParseField(reader)
         settings.SetField(field[0], field[1], field[2])
       elif ExperimentFile._CLOSE_SETTINGS_RE.match(line):
@@ -113,7 +114,8 @@ class ExperimentFile(object):
 
         if not line:
           continue
-        elif ExperimentFile._OPEN_SETTINGS_RE.match(line):
+
+        if ExperimentFile._OPEN_SETTINGS_RE.match(line):
           new_settings, settings_type = self._ParseSettings(reader)
           # We will allow benchmarks with duplicated settings name for now.
           # Further decision will be made when parsing benchmark details in
diff --git a/crosperf/machine_manager.py b/crosperf/machine_manager.py
index 7211662c..0b38eef2 100644
--- a/crosperf/machine_manager.py
+++ b/crosperf/machine_manager.py
@@ -28,12 +28,10 @@ CHECKSUM_FILE = '/usr/local/osimage_checksum_file'
 
 class BadChecksum(Exception):
   """Raised if all machines for a label don't have the same checksum."""
-  pass
 
 
 class BadChecksumString(Exception):
   """Raised if all machines for a label don't have the same checksum string."""
-  pass
 
 
 class MissingLocksDirectory(Exception):
@@ -298,8 +296,8 @@ class MachineManager(object):
         retval = image_chromeos.DoImage(image_chromeos_args)
       if retval:
         raise RuntimeError("Could not image machine: '%s'." % machine.name)
-      else:
-        self.num_reimages += 1
+
+      self.num_reimages += 1
       machine.checksum = checksum
       machine.image = label.chromeos_image
       machine.label = label
diff --git a/crosperf/results_report_templates.py b/crosperf/results_report_templates.py
index 3c5258c9..ea411e21 100644
--- a/crosperf/results_report_templates.py
+++ b/crosperf/results_report_templates.py
@@ -6,7 +6,7 @@
 """Text templates used by various parts of results_report."""
 from __future__ import print_function
 
-import cgi
+import html
 from string import Template
 
 _TabMenuTemplate = Template("""
@@ -19,7 +19,7 @@ _TabMenuTemplate = Template("""
 
 def _GetTabMenuHTML(table_name):
   # N.B. cgi.escape does some very basic HTML escaping. Nothing more.
-  escaped = cgi.escape(table_name, quote=True)
+  escaped = html.escape(table_name)
   return _TabMenuTemplate.substitute(table_name=escaped)
 
 
@@ -35,7 +35,7 @@ _ExperimentFileHTML = """
 def _GetExperimentFileHTML(experiment_file_text):
   if not experiment_file_text:
     return ''
-  return _ExperimentFileHTML % (cgi.escape(experiment_file_text),)
+  return _ExperimentFileHTML % (html.escape(experiment_file_text, quote=False),)
 
 
 _ResultsSectionHTML = Template("""
diff --git a/crosperf/suite_runner.py b/crosperf/suite_runner.py
index 79ace20d..62a85cc6 100644
--- a/crosperf/suite_runner.py
+++ b/crosperf/suite_runner.py
@@ -166,11 +166,10 @@ class SuiteRunner(object):
     # process namespace and we can kill process created easily by their
     # process group.
     chrome_root_options = ('--no-ns-pid '
-                           '--chrome_root={} --chrome_root_mount={} '
+                           '--chrome_root={0} --chrome_root_mount={1} '
                            'FEATURES="-usersandbox" '
-                           'CHROME_ROOT={}'.format(label.chrome_src,
-                                                   CHROME_MOUNT_DIR,
-                                                   CHROME_MOUNT_DIR))
+                           'CHROME_ROOT={1}'.format(label.chrome_src,
+                                                    CHROME_MOUNT_DIR))
 
     if self.log_level != 'verbose':
       self.logger.LogOutput('Running test.')
diff --git a/lock_machine.py b/lock_machine.py
index 06c0e80c..2948381d 100755
--- a/lock_machine.py
+++ b/lock_machine.py
@@ -518,12 +518,6 @@ def Main(argv):
       lock_manager.CheckMachineLocks(machine_states, cmd)
       lock_manager.UpdateMachines(False)
 
-  elif cmd == 'add':
-    lock_manager.AddMachinesToLocalServer()
-
-  elif cmd == 'remove':
-    lock_manager.RemoveMachinesFromLocalServer()
-
   return 0