[dev.boringcrypto] all: merge commit 9d0819b27c (CL 314609) into dev.boringcrypto

There used to be two BoringCrypto-specific behaviors related to cipher
suites in crypto/tls:

1. in FIPS-only mode, only a restricted set of AES ciphers is allowed

2. NOT in FIPS-only mode, AES would be prioritized over ChaCha20 even if
   AES hardware was not available

The motivation of (2) is unclear, and BoringSSL doesn't have equivalent
logic. This merge drops (2), and keeps (1). Note that the list of
FIPS-only ciphers does not have priority semantics anymore, but the
default logic still sorts them the same way as they used to be.

Change-Id: I50544011085cfa2b087f323aebf5338c0bd2dd33

59 files changed, 627 insertions, 161 deletions

diff --git a/misc/android/go_android_exec.go b/misc/android/go_android_exec.go
index 7aa7fe56fc..3af2bee583 100644
--- a/misc/android/go_android_exec.go
+++ b/misc/android/go_android_exec.go
@@ -14,7 +14,6 @@ import (
 	"fmt"
 	"go/build"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -276,7 +275,7 @@ func adbCopyGoroot() error {
 	if err := syscall.Flock(int(stat.Fd()), syscall.LOCK_EX); err != nil {
 		return err
 	}
-	s, err := ioutil.ReadAll(stat)
+	s, err := io.ReadAll(stat)
 	if err != nil {
 		return err
 	}
@@ -294,7 +293,7 @@ func adbCopyGoroot() error {
 	goroot := runtime.GOROOT()
 	// Build go for android.
 	goCmd := filepath.Join(goroot, "bin", "go")
-	tmpGo, err := ioutil.TempFile("", "go_android_exec-cmd-go-*")
+	tmpGo, err := os.CreateTemp("", "go_android_exec-cmd-go-*")
 	if err != nil {
 		return err
 	}
diff --git a/misc/cgo/errors/argposition_test.go b/misc/cgo/errors/argposition_test.go
new file mode 100644
index 0000000000..331095f747
--- /dev/null
+++ b/misc/cgo/errors/argposition_test.go
@@ -0,0 +1,134 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 42580: cmd/cgo: shifting identifier position in ast
+
+package errorstest
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+type ShortPosition struct {
+	Line    int
+	Column  int
+	Visited bool
+}
+
+type IdentPositionInfo map[string][]ShortPosition
+
+type Visitor struct {
+	identPosInfo IdentPositionInfo
+	fset         *token.FileSet
+	t            *testing.T
+}
+
+func (v *Visitor) Visit(node ast.Node) ast.Visitor {
+	if ident, ok := node.(*ast.Ident); ok {
+		if expectedPositions, ok := v.identPosInfo[ident.Name]; ok {
+			gotMatch := false
+			var errorMessage strings.Builder
+			for caseIndex, expectedPos := range expectedPositions {
+				actualPosition := v.fset.PositionFor(ident.Pos(), true)
+				errorOccured := false
+				if expectedPos.Line != actualPosition.Line {
+					fmt.Fprintf(&errorMessage, "wrong line number for ident %s: expected: %d got: %d\n", ident.Name, expectedPos.Line, actualPosition.Line)
+					errorOccured = true
+				}
+				if expectedPos.Column != actualPosition.Column {
+					fmt.Fprintf(&errorMessage, "wrong column number for ident %s: expected: %d got: %d\n", ident.Name, expectedPos.Column, actualPosition.Column)
+					errorOccured = true
+				}
+				if errorOccured {
+					continue
+				}
+				gotMatch = true
+				expectedPositions[caseIndex].Visited = true
+			}
+
+			if !gotMatch {
+				v.t.Errorf(errorMessage.String())
+			}
+		}
+	}
+	return v
+}
+
+func TestArgumentsPositions(t *testing.T) {
+	testdata, err := filepath.Abs("testdata")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	tmpPath := t.TempDir()
+
+	dir := filepath.Join(tmpPath, "src", "testpositions")
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		t.Fatal(err)
+	}
+
+	cmd := exec.Command("go", "tool", "cgo",
+		"-srcdir", testdata,
+		"-objdir", dir,
+		"issue42580.go")
+	cmd.Stderr = new(bytes.Buffer)
+
+	err = cmd.Run()
+	if err != nil {
+		t.Fatalf("%s: %v\n%s", cmd, err, cmd.Stderr)
+	}
+	mainProcessed, err := ioutil.ReadFile(filepath.Join(dir, "issue42580.cgo1.go"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "", mainProcessed, parser.AllErrors)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+
+	expectation := IdentPositionInfo{
+		"checkedPointer": []ShortPosition{
+			ShortPosition{
+				Line:   32,
+				Column: 56,
+			},
+		},
+		"singleInnerPointerChecked": []ShortPosition{
+			ShortPosition{
+				Line:   37,
+				Column: 91,
+			},
+		},
+		"doublePointerChecked": []ShortPosition{
+			ShortPosition{
+				Line:   42,
+				Column: 91,
+			},
+		},
+	}
+	for _, decl := range f.Decls {
+		if fdecl, ok := decl.(*ast.FuncDecl); ok {
+			ast.Walk(&Visitor{expectation, fset, t}, fdecl.Body)
+		}
+	}
+	for ident, positions := range expectation {
+		for _, position := range positions {
+			if !position.Visited {
+				t.Errorf("Position %d:%d missed for %s ident", position.Line, position.Column, ident)
+			}
+		}
+	}
+}
diff --git a/misc/cgo/errors/badsym_test.go b/misc/cgo/errors/badsym_test.go
index b2701bf922..fc687567bf 100644
--- a/misc/cgo/errors/badsym_test.go
+++ b/misc/cgo/errors/badsym_test.go
@@ -6,7 +6,6 @@ package errorstest
 
 import (
 	"bytes"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -55,7 +54,7 @@ func TestBadSymbol(t *testing.T) {
 
 	makeFile := func(mdir, base, source string) string {
 		ret := filepath.Join(mdir, base)
-		if err := ioutil.WriteFile(ret, []byte(source), 0644); err != nil {
+		if err := os.WriteFile(ret, []byte(source), 0644); err != nil {
 			t.Fatal(err)
 		}
 		return ret
@@ -100,7 +99,7 @@ func TestBadSymbol(t *testing.T) {
 	// _cgo_import.go.
 
 	rewrite := func(from, to string) {
-		obj, err := ioutil.ReadFile(from)
+		obj, err := os.ReadFile(from)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -115,7 +114,7 @@ func TestBadSymbol(t *testing.T) {
 
 		obj = bytes.ReplaceAll(obj, []byte(magicInput), []byte(magicReplace))
 
-		if err := ioutil.WriteFile(to, obj, 0644); err != nil {
+		if err := os.WriteFile(to, obj, 0644); err != nil {
 			t.Fatal(err)
 		}
 	}
diff --git a/misc/cgo/errors/errors_test.go b/misc/cgo/errors/errors_test.go
index 1bdf843451..a077b59478 100644
--- a/misc/cgo/errors/errors_test.go
+++ b/misc/cgo/errors/errors_test.go
@@ -7,7 +7,6 @@ package errorstest
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -25,7 +24,7 @@ func check(t *testing.T, file string) {
 	t.Run(file, func(t *testing.T) {
 		t.Parallel()
 
-		contents, err := ioutil.ReadFile(path(file))
+		contents, err := os.ReadFile(path(file))
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -56,7 +55,7 @@ func check(t *testing.T, file string) {
 }
 
 func expect(t *testing.T, file string, errors []*regexp.Regexp) {
-	dir, err := ioutil.TempDir("", filepath.Base(t.Name()))
+	dir, err := os.MkdirTemp("", filepath.Base(t.Name()))
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/misc/cgo/errors/ptr_test.go b/misc/cgo/errors/ptr_test.go
index 4a46b6023b..0f39dc8e54 100644
--- a/misc/cgo/errors/ptr_test.go
+++ b/misc/cgo/errors/ptr_test.go
@@ -10,7 +10,6 @@ import (
 	"bytes"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -463,7 +462,7 @@ func buildPtrTests(t *testing.T) (dir, exe string) {
 		gopath = *tmp
 		dir = ""
 	} else {
-		d, err := ioutil.TempDir("", filepath.Base(t.Name()))
+		d, err := os.MkdirTemp("", filepath.Base(t.Name()))
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -475,7 +474,7 @@ func buildPtrTests(t *testing.T) (dir, exe string) {
 	if err := os.MkdirAll(src, 0777); err != nil {
 		t.Fatal(err)
 	}
-	if err := ioutil.WriteFile(filepath.Join(src, "go.mod"), []byte("module ptrtest"), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(src, "go.mod"), []byte("module ptrtest"), 0666); err != nil {
 		t.Fatal(err)
 	}
 
@@ -535,10 +534,10 @@ func buildPtrTests(t *testing.T) (dir, exe string) {
 	fmt.Fprintf(&cgo1, "}\n\n")
 	fmt.Fprintf(&cgo1, "%s\n", ptrTestMain)
 
-	if err := ioutil.WriteFile(filepath.Join(src, "cgo1.go"), cgo1.Bytes(), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(src, "cgo1.go"), cgo1.Bytes(), 0666); err != nil {
 		t.Fatal(err)
 	}
-	if err := ioutil.WriteFile(filepath.Join(src, "cgo2.go"), cgo2.Bytes(), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(src, "cgo2.go"), cgo2.Bytes(), 0666); err != nil {
 		t.Fatal(err)
 	}
 
diff --git a/misc/cgo/errors/testdata/issue42580.go b/misc/cgo/errors/testdata/issue42580.go
new file mode 100644
index 0000000000..aba80dfeba
--- /dev/null
+++ b/misc/cgo/errors/testdata/issue42580.go
@@ -0,0 +1,44 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 42580: cmd/cgo: shifting identifier position in ast
+
+package cgotest
+
+// typedef int (*intFunc) ();
+//
+// char* strarg = "";
+//
+// int func_with_char(char* arg, void* dummy)
+// {return 5;}
+//
+// int* get_arr(char* arg, void* dummy)
+// {return NULL;}
+import "C"
+import "unsafe"
+
+// Test variables
+var (
+	checkedPointer            = []byte{1}
+	doublePointerChecked      = []byte{1}
+	singleInnerPointerChecked = []byte{1}
+)
+
+// This test checks the positions of variable identifiers.
+// Changing the positions of the test variables idents after this point will break the test.
+
+func TestSingleArgumentCast() C.int {
+	retcode := C.func_with_char((*C.char)(unsafe.Pointer(&checkedPointer[0])), unsafe.Pointer(C.strarg))
+	return retcode
+}
+
+func TestSingleArgumentCastRecFuncAsSimpleArg() C.int {
+	retcode := C.func_with_char((*C.char)(unsafe.Pointer(C.get_arr((*C.char)(unsafe.Pointer(&singleInnerPointerChecked[0])), unsafe.Pointer(C.strarg)))), nil)
+	return retcode
+}
+
+func TestSingleArgumentCastRecFunc() C.int {
+	retcode := C.func_with_char((*C.char)(unsafe.Pointer(C.get_arr((*C.char)(unsafe.Pointer(&doublePointerChecked[0])), unsafe.Pointer(C.strarg)))), unsafe.Pointer(C.strarg))
+	return retcode
+}
diff --git a/misc/cgo/life/life_test.go b/misc/cgo/life/life_test.go
index 3c95d87d8a..0becb262b4 100644
--- a/misc/cgo/life/life_test.go
+++ b/misc/cgo/life/life_test.go
@@ -6,7 +6,6 @@ package life_test
 
 import (
 	"bytes"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -21,7 +20,7 @@ func TestMain(m *testing.M) {
 }
 
 func testMain(m *testing.M) int {
-	GOPATH, err := ioutil.TempDir("", "cgolife")
+	GOPATH, err := os.MkdirTemp("", "cgolife")
 	if err != nil {
 		log.Panic(err)
 	}
@@ -38,7 +37,7 @@ func testMain(m *testing.M) int {
 		log.Panic(err)
 	}
 	os.Setenv("PWD", modRoot)
-	if err := ioutil.WriteFile("go.mod", []byte("module cgolife\n"), 0666); err != nil {
+	if err := os.WriteFile("go.mod", []byte("module cgolife\n"), 0666); err != nil {
 		log.Panic(err)
 	}
 
diff --git a/misc/cgo/stdio/stdio_test.go b/misc/cgo/stdio/stdio_test.go
index ab5d328f67..675418f98d 100644
--- a/misc/cgo/stdio/stdio_test.go
+++ b/misc/cgo/stdio/stdio_test.go
@@ -6,7 +6,6 @@ package stdio_test
 
 import (
 	"bytes"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -21,7 +20,7 @@ func TestMain(m *testing.M) {
 }
 
 func testMain(m *testing.M) int {
-	GOPATH, err := ioutil.TempDir("", "cgostdio")
+	GOPATH, err := os.MkdirTemp("", "cgostdio")
 	if err != nil {
 		log.Panic(err)
 	}
@@ -38,7 +37,7 @@ func testMain(m *testing.M) int {
 		log.Panic(err)
 	}
 	os.Setenv("PWD", modRoot)
-	if err := ioutil.WriteFile("go.mod", []byte("module cgostdio\n"), 0666); err != nil {
+	if err := os.WriteFile("go.mod", []byte("module cgostdio\n"), 0666); err != nil {
 		log.Panic(err)
 	}
 
diff --git a/misc/cgo/test/cgo_test.go b/misc/cgo/test/cgo_test.go
index f7a76d047b..143f23f0e0 100644
--- a/misc/cgo/test/cgo_test.go
+++ b/misc/cgo/test/cgo_test.go
@@ -59,6 +59,7 @@ func Test28896(t *testing.T)                 { test28896(t) }
 func Test30065(t *testing.T)                 { test30065(t) }
 func Test32579(t *testing.T)                 { test32579(t) }
 func Test31891(t *testing.T)                 { test31891(t) }
+func Test45451(t *testing.T)                 { test45451(t) }
 func TestAlign(t *testing.T)                 { testAlign(t) }
 func TestAtol(t *testing.T)                  { testAtol(t) }
 func TestBlocking(t *testing.T)              { testBlocking(t) }
@@ -80,6 +81,7 @@ func TestNamedEnum(t *testing.T)             { testNamedEnum(t) }
 func TestCastToEnum(t *testing.T)            { testCastToEnum(t) }
 func TestErrno(t *testing.T)                 { testErrno(t) }
 func TestFpVar(t *testing.T)                 { testFpVar(t) }
+func TestHandle(t *testing.T)                { testHandle(t) }
 func TestHelpers(t *testing.T)               { testHelpers(t) }
 func TestLibgcc(t *testing.T)                { testLibgcc(t) }
 func TestMultipleAssign(t *testing.T)        { testMultipleAssign(t) }
diff --git a/misc/cgo/test/issue1435.go b/misc/cgo/test/issue1435.go
index a1c7cacde7..cf34ce8db6 100644
--- a/misc/cgo/test/issue1435.go
+++ b/misc/cgo/test/issue1435.go
@@ -8,7 +8,7 @@ package cgotest
 
 import (
 	"fmt"
-	"io/ioutil"
+	"os"
 	"strings"
 	"syscall"
 	"testing"
@@ -64,7 +64,7 @@ import "C"
 func compareStatus(filter, expect string) error {
 	expected := filter + expect
 	pid := syscall.Getpid()
-	fs, err := ioutil.ReadDir(fmt.Sprintf("/proc/%d/task", pid))
+	fs, err := os.ReadDir(fmt.Sprintf("/proc/%d/task", pid))
 	if err != nil {
 		return fmt.Errorf("unable to find %d tasks: %v", pid, err)
 	}
@@ -72,7 +72,7 @@ func compareStatus(filter, expect string) error {
 	foundAThread := false
 	for _, f := range fs {
 		tf := fmt.Sprintf("/proc/%s/status", f.Name())
-		d, err := ioutil.ReadFile(tf)
+		d, err := os.ReadFile(tf)
 		if err != nil {
 			// There are a surprising number of ways this
 			// can error out on linux.  We've seen all of
diff --git a/misc/cgo/test/issue6997_linux.go b/misc/cgo/test/issue6997_linux.go
index 0c98ea0794..f19afb8b7a 100644
--- a/misc/cgo/test/issue6997_linux.go
+++ b/misc/cgo/test/issue6997_linux.go
@@ -5,7 +5,7 @@
 // +build !android
 
 // Test that pthread_cancel works as expected
-// (NPTL uses SIGRTMIN to implement thread cancelation)
+// (NPTL uses SIGRTMIN to implement thread cancellation)
 // See https://golang.org/issue/6997
 package cgotest
 
@@ -17,8 +17,10 @@ extern int CancelThread();
 */
 import "C"
 
-import "testing"
-import "time"
+import (
+	"testing"
+	"time"
+)
 
 func test6997(t *testing.T) {
 	r := C.StartThread()
diff --git a/misc/cgo/test/issue8148.c b/misc/cgo/test/issue8148.c
new file mode 100644
index 0000000000..927b4346cb
--- /dev/null
+++ b/misc/cgo/test/issue8148.c
@@ -0,0 +1,11 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "_cgo_export.h"
+
+int get8148(void) {
+	T t;
+	t.i = 42;
+	return issue8148Callback(&t);
+}
diff --git a/misc/cgo/test/issue8148.go b/misc/cgo/test/issue8148.go
index f704788aef..aee9003d50 100644
--- a/misc/cgo/test/issue8148.go
+++ b/misc/cgo/test/issue8148.go
@@ -10,14 +10,7 @@ package cgotest
 
 /*
 typedef struct { int i; } T;
-
-int issue8148Callback(T*);
-
-static int get() {
-	T t;
-	t.i = 42;
-	return issue8148Callback(&t);
-}
+int get8148(void);
 */
 import "C"
 
@@ -27,5 +20,5 @@ func issue8148Callback(t *C.T) C.int {
 }
 
 func Issue8148() int {
-	return int(C.get())
+	return int(C.get8148())
 }
diff --git a/misc/cgo/test/pkg_test.go b/misc/cgo/test/pkg_test.go
index 94abaa03e8..14013a4cd9 100644
--- a/misc/cgo/test/pkg_test.go
+++ b/misc/cgo/test/pkg_test.go
@@ -5,7 +5,6 @@
 package cgotest
 
 import (
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -37,7 +36,7 @@ func TestCrossPackageTests(t *testing.T) {
 		}
 	}
 
-	GOPATH, err := ioutil.TempDir("", "cgotest")
+	GOPATH, err := os.MkdirTemp("", "cgotest")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -47,7 +46,7 @@ func TestCrossPackageTests(t *testing.T) {
 	if err := overlayDir(modRoot, "testdata"); err != nil {
 		t.Fatal(err)
 	}
-	if err := ioutil.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgotest\n"), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgotest\n"), 0666); err != nil {
 		t.Fatal(err)
 	}
 
diff --git a/misc/cgo/test/setgid_linux.go b/misc/cgo/test/setgid_linux.go
index 6773f94d3d..7c64946cb3 100644
--- a/misc/cgo/test/setgid_linux.go
+++ b/misc/cgo/test/setgid_linux.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Test that setgid does not hang on GNU/Linux.
+// Test that setgid does not hang on Linux.
 // See https://golang.org/issue/3871 for details.
 
 package cgotest
diff --git a/misc/cgo/test/test.go b/misc/cgo/test/test.go
index 65823b1ca0..3b8f548b13 100644
--- a/misc/cgo/test/test.go
+++ b/misc/cgo/test/test.go
@@ -899,6 +899,10 @@ static uint16_t issue31093F(uint16_t v) { return v; }
 // issue 32579
 typedef struct S32579 { unsigned char data[1]; } S32579;
 
+// issue 37033, cgo.Handle
+extern void GoFunc37033(uintptr_t handle);
+void cFunc37033(uintptr_t handle) { GoFunc37033(handle); }
+
 // issue 38649
 // Test that #define'd type aliases work.
 #define netbsd_gid unsigned int
@@ -908,6 +912,9 @@ typedef struct S32579 { unsigned char data[1]; } S32579;
 enum Enum40494 { X_40494 };
 union Union40494 { int x; };
 void issue40494(enum Enum40494 e, union Union40494* up) {}
+
+// Issue 45451, bad handling of go:notinheap types.
+typedef struct issue45451Undefined issue45451;
 */
 import "C"
 
@@ -920,6 +927,7 @@ import (
 	"os/signal"
 	"reflect"
 	"runtime"
+	"runtime/cgo"
 	"sync"
 	"syscall"
 	"testing"
@@ -2230,6 +2238,23 @@ func test32579(t *testing.T) {
 	}
 }
 
+// issue 37033, check if cgo.Handle works properly
+
+func testHandle(t *testing.T) {
+	ch := make(chan int)
+
+	for i := 0; i < 42; i++ {
+		h := cgo.NewHandle(ch)
+		go func() {
+			C.cFunc37033(C.uintptr_t(h))
+		}()
+		if v := <-ch; issue37033 != v {
+			t.Fatalf("unexpected receiving value: got %d, want %d", v, issue37033)
+		}
+		h.Delete()
+	}
+}
+
 // issue 38649
 
 var issue38649 C.netbsd_gid = 42
@@ -2244,3 +2269,19 @@ var issue39877 *C.void = nil
 func Issue40494() {
 	C.issue40494(C.enum_Enum40494(C.X_40494), (*C.union_Union40494)(nil))
 }
+
+// Issue 45451.
+func test45451(t *testing.T) {
+	var u *C.issue45451
+	typ := reflect.ValueOf(u).Type().Elem()
+
+	// The type is undefined in C so allocating it should panic.
+	defer func() {
+		if r := recover(); r == nil {
+			t.Error("expected panic")
+		}
+	}()
+
+	_ = reflect.New(typ)
+	t.Errorf("reflect.New(%v) should have panicked", typ)
+}
diff --git a/misc/cgo/test/testdata/issue9400/asm_386.s b/misc/cgo/test/testdata/issue9400/asm_386.s
index 7f158b5c39..96b8b60c10 100644
--- a/misc/cgo/test/testdata/issue9400/asm_386.s
+++ b/misc/cgo/test/testdata/issue9400/asm_386.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testdata/issue9400/asm_amd64x.s b/misc/cgo/test/testdata/issue9400/asm_amd64x.s
index 48b86190a5..99509bce5e 100644
--- a/misc/cgo/test/testdata/issue9400/asm_amd64x.s
+++ b/misc/cgo/test/testdata/issue9400/asm_amd64x.s
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build amd64 amd64p32
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testdata/issue9400/asm_arm.s b/misc/cgo/test/testdata/issue9400/asm_arm.s
index 96c278520f..cc92856c2f 100644
--- a/misc/cgo/test/testdata/issue9400/asm_arm.s
+++ b/misc/cgo/test/testdata/issue9400/asm_arm.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testdata/issue9400/asm_arm64.s b/misc/cgo/test/testdata/issue9400/asm_arm64.s
index 2ebbfcca3b..2565793f9a 100644
--- a/misc/cgo/test/testdata/issue9400/asm_arm64.s
+++ b/misc/cgo/test/testdata/issue9400/asm_arm64.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testdata/issue9400/asm_mips64x.s b/misc/cgo/test/testdata/issue9400/asm_mips64x.s
index 63dc90605e..693231ddfe 100644
--- a/misc/cgo/test/testdata/issue9400/asm_mips64x.s
+++ b/misc/cgo/test/testdata/issue9400/asm_mips64x.s
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build mips64 mips64le
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testdata/issue9400/asm_mipsx.s b/misc/cgo/test/testdata/issue9400/asm_mipsx.s
index 7a92735194..63261bbf9d 100644
--- a/misc/cgo/test/testdata/issue9400/asm_mipsx.s
+++ b/misc/cgo/test/testdata/issue9400/asm_mipsx.s
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build mips mipsle
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testdata/issue9400/asm_ppc64x.s b/misc/cgo/test/testdata/issue9400/asm_ppc64x.s
index c88ec3b21e..b5613fb6ec 100644
--- a/misc/cgo/test/testdata/issue9400/asm_ppc64x.s
+++ b/misc/cgo/test/testdata/issue9400/asm_ppc64x.s
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build ppc64 ppc64le
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testdata/issue9400/asm_riscv64.s b/misc/cgo/test/testdata/issue9400/asm_riscv64.s
index 20fcc0066d..244dadac35 100644
--- a/misc/cgo/test/testdata/issue9400/asm_riscv64.s
+++ b/misc/cgo/test/testdata/issue9400/asm_riscv64.s
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build riscv64
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testdata/issue9400/asm_s390x.s b/misc/cgo/test/testdata/issue9400/asm_s390x.s
index fc9ad724c1..4856492958 100644
--- a/misc/cgo/test/testdata/issue9400/asm_s390x.s
+++ b/misc/cgo/test/testdata/issue9400/asm_s390x.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/test/testx.c b/misc/cgo/test/testx.c
new file mode 100644
index 0000000000..1258e326a4
--- /dev/null
+++ b/misc/cgo/test/testx.c
@@ -0,0 +1,24 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "_cgo_export.h"
+
+void lockOSThreadC(void) {
+	lockOSThreadCallback();
+}
+
+void issue7978c(uint32_t *sync) {
+	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 0)
+		;
+	__atomic_add_fetch(sync, 1, __ATOMIC_SEQ_CST);
+	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 2)
+		;
+	issue7978cb();
+	__atomic_add_fetch(sync, 1, __ATOMIC_SEQ_CST);
+	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 6)
+		;
+}
+
+void f7665(void) {
+}
diff --git a/misc/cgo/test/testx.go b/misc/cgo/test/testx.go
index 2b2e69ec00..823c3e13d2 100644
--- a/misc/cgo/test/testx.go
+++ b/misc/cgo/test/testx.go
@@ -12,6 +12,7 @@ package cgotest
 
 import (
 	"runtime"
+	"runtime/cgo"
 	"runtime/debug"
 	"strings"
 	"sync"
@@ -26,7 +27,6 @@ import (
 extern void doAdd(int, int);
 
 // issue 1328
-extern void BackIntoGo(void);
 void IntoC(void);
 
 // issue 1560
@@ -38,11 +38,7 @@ long long mysleep(int seconds);
 long long twoSleep(int);
 
 // issue 3775
-void lockOSThreadCallback(void);
-inline static void lockOSThreadC(void)
-{
-        lockOSThreadCallback();
-}
+void lockOSThreadC(void);
 int usleep(unsigned usec);
 
 // issue 4054 part 2 - part 1 in test.go
@@ -81,21 +77,9 @@ extern void f7665(void);
 
 #include <stdint.h>
 
-void issue7978cb(void);
-
 // use ugly atomic variable sync since that doesn't require calling back into
 // Go code or OS dependencies
-static void issue7978c(uint32_t *sync) {
-	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 0)
-		;
-	__atomic_add_fetch(sync, 1, __ATOMIC_SEQ_CST);
-	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 2)
-		;
-	issue7978cb();
-	__atomic_add_fetch(sync, 1, __ATOMIC_SEQ_CST);
-	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 6)
-		;
-}
+void issue7978c(uint32_t *sync);
 
 // issue 8331 part 2 - part 1 in test.go
 // A typedef of an unnamed struct is the same struct when
@@ -428,9 +412,6 @@ func test6907Go(t *testing.T) {
 
 // issue 7665
 
-//export f7665
-func f7665() {}
-
 var bad7665 unsafe.Pointer = C.f7665
 var good7665 uintptr = uintptr(C.f7665)
 
@@ -558,6 +539,17 @@ func test31891(t *testing.T) {
 	C.callIssue31891()
 }
 
+// issue 37033, check if cgo.Handle works properly
+
+var issue37033 = 42
+
+//export GoFunc37033
+func GoFunc37033(handle C.uintptr_t) {
+	h := cgo.Handle(handle)
+	ch := h.Value().(chan int)
+	ch <- issue37033
+}
+
 // issue 38408
 // A typedef pointer can be used as the element type.
 // No runtime test; just make sure it compiles.
diff --git a/misc/cgo/testcarchive/carchive_test.go b/misc/cgo/testcarchive/carchive_test.go
index 6a5adf79ca..55be3c5f70 100644
--- a/misc/cgo/testcarchive/carchive_test.go
+++ b/misc/cgo/testcarchive/carchive_test.go
@@ -10,7 +10,6 @@ import (
 	"debug/elf"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -53,7 +52,7 @@ func testMain(m *testing.M) int {
 	// We need a writable GOPATH in which to run the tests.
 	// Construct one in a temporary directory.
 	var err error
-	GOPATH, err = ioutil.TempDir("", "carchive_test")
+	GOPATH, err = os.MkdirTemp("", "carchive_test")
 	if err != nil {
 		log.Panic(err)
 	}
@@ -74,7 +73,7 @@ func testMain(m *testing.M) int {
 		log.Panic(err)
 	}
 	os.Setenv("PWD", modRoot)
-	if err := ioutil.WriteFile("go.mod", []byte("module testcarchive\n"), 0666); err != nil {
+	if err := os.WriteFile("go.mod", []byte("module testcarchive\n"), 0666); err != nil {
 		log.Panic(err)
 	}
 
@@ -176,7 +175,7 @@ func genHeader(t *testing.T, header, dir string) {
 	// The 'cgo' command generates a number of additional artifacts,
 	// but we're only interested in the header.
 	// Shunt the rest of the outputs to a temporary directory.
-	objDir, err := ioutil.TempDir(GOPATH, "_obj")
+	objDir, err := os.MkdirTemp(GOPATH, "_obj")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -252,7 +251,7 @@ var badLineRegexp = regexp.MustCompile(`(?m)^#line [0-9]+ "/.*$`)
 // the user and make the files change based on details of the location
 // of GOPATH.
 func checkLineComments(t *testing.T, hdrname string) {
-	hdr, err := ioutil.ReadFile(hdrname)
+	hdr, err := os.ReadFile(hdrname)
 	if err != nil {
 		if !os.IsNotExist(err) {
 			t.Error(err)
@@ -618,7 +617,7 @@ func TestExtar(t *testing.T) {
 		t.Fatal(err)
 	}
 	s := strings.Replace(testar, "PWD", dir, 1)
-	if err := ioutil.WriteFile("testar", []byte(s), 0777); err != nil {
+	if err := os.WriteFile("testar", []byte(s), 0777); err != nil {
 		t.Fatal(err)
 	}
 
@@ -776,7 +775,7 @@ func TestSIGPROF(t *testing.T) {
 // tool with -buildmode=c-archive, it passes -shared to the compiler,
 // so we override that. The go tool doesn't work this way, but Bazel
 // will likely do it in the future. And it ought to work. This test
-// was added because at one time it did not work on PPC GNU/Linux.
+// was added because at one time it did not work on PPC Linux.
 func TestCompileWithoutShared(t *testing.T) {
 	// For simplicity, reuse the signal forwarding test.
 	checkSignalForwardingTest(t)
diff --git a/misc/cgo/testcarchive/testdata/libgo6/sigprof.go b/misc/cgo/testcarchive/testdata/libgo6/sigprof.go
index 4cb05dc617..31527c59af 100644
--- a/misc/cgo/testcarchive/testdata/libgo6/sigprof.go
+++ b/misc/cgo/testcarchive/testdata/libgo6/sigprof.go
@@ -5,7 +5,7 @@
 package main
 
 import (
-	"io/ioutil"
+	"io"
 	"runtime/pprof"
 )
 
@@ -13,7 +13,7 @@ import "C"
 
 //export go_start_profile
 func go_start_profile() {
-	pprof.StartCPUProfile(ioutil.Discard)
+	pprof.StartCPUProfile(io.Discard)
 }
 
 //export go_stop_profile
diff --git a/misc/cgo/testcarchive/testdata/main_unix.c b/misc/cgo/testcarchive/testdata/main_unix.c
index b23ac1c242..bd00f9d233 100644
--- a/misc/cgo/testcarchive/testdata/main_unix.c
+++ b/misc/cgo/testcarchive/testdata/main_unix.c
@@ -36,7 +36,7 @@ int install_handler() {
 		return 2;
 	}
 	// gccgo does not set SA_ONSTACK for SIGSEGV.
-	if (getenv("GCCGO") == "" && (osa.sa_flags&SA_ONSTACK) == 0) {
+	if (getenv("GCCGO") == NULL && (osa.sa_flags&SA_ONSTACK) == 0) {
 		fprintf(stderr, "Go runtime did not install signal handler\n");
 		return 2;
 	}
diff --git a/misc/cgo/testcshared/cshared_test.go b/misc/cgo/testcshared/cshared_test.go
index 3a4886cf30..90d8c365e6 100644
--- a/misc/cgo/testcshared/cshared_test.go
+++ b/misc/cgo/testcshared/cshared_test.go
@@ -11,7 +11,6 @@ import (
 	"encoding/binary"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -125,7 +124,7 @@ func testMain(m *testing.M) int {
 	// Copy testdata into GOPATH/src/testcshared, along with a go.mod file
 	// declaring the same path.
 
-	GOPATH, err := ioutil.TempDir("", "cshared_test")
+	GOPATH, err := os.MkdirTemp("", "cshared_test")
 	if err != nil {
 		log.Panic(err)
 	}
@@ -140,7 +139,7 @@ func testMain(m *testing.M) int {
 		log.Panic(err)
 	}
 	os.Setenv("PWD", modRoot)
-	if err := ioutil.WriteFile("go.mod", []byte("module testcshared\n"), 0666); err != nil {
+	if err := os.WriteFile("go.mod", []byte("module testcshared\n"), 0666); err != nil {
 		log.Panic(err)
 	}
 
@@ -260,7 +259,7 @@ func createHeaders() error {
 	// The 'cgo' command generates a number of additional artifacts,
 	// but we're only interested in the header.
 	// Shunt the rest of the outputs to a temporary directory.
-	objDir, err := ioutil.TempDir("", "testcshared_obj")
+	objDir, err := os.MkdirTemp("", "testcshared_obj")
 	if err != nil {
 		return err
 	}
@@ -381,7 +380,7 @@ func main() {
 
 	srcfile := filepath.Join(tmpdir, "test.go")
 	objfile := filepath.Join(tmpdir, "test.dll")
-	if err := ioutil.WriteFile(srcfile, []byte(prog), 0666); err != nil {
+	if err := os.WriteFile(srcfile, []byte(prog), 0666); err != nil {
 		t.Fatal(err)
 	}
 	argv := []string{"build", "-buildmode=c-shared"}
@@ -643,7 +642,7 @@ func TestPIE(t *testing.T) {
 
 // Test that installing a second time recreates the header file.
 func TestCachedInstall(t *testing.T) {
-	tmpdir, err := ioutil.TempDir("", "cshared")
+	tmpdir, err := os.MkdirTemp("", "cshared")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -719,14 +718,14 @@ func TestCachedInstall(t *testing.T) {
 // copyFile copies src to dst.
 func copyFile(t *testing.T, dst, src string) {
 	t.Helper()
-	data, err := ioutil.ReadFile(src)
+	data, err := os.ReadFile(src)
 	if err != nil {
 		t.Fatal(err)
 	}
 	if err := os.MkdirAll(filepath.Dir(dst), 0777); err != nil {
 		t.Fatal(err)
 	}
-	if err := ioutil.WriteFile(dst, data, 0666); err != nil {
+	if err := os.WriteFile(dst, data, 0666); err != nil {
 		t.Fatal(err)
 	}
 }
@@ -743,7 +742,7 @@ func TestGo2C2Go(t *testing.T) {
 
 	t.Parallel()
 
-	tmpdir, err := ioutil.TempDir("", "cshared-TestGo2C2Go")
+	tmpdir, err := os.MkdirTemp("", "cshared-TestGo2C2Go")
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/misc/cgo/testgodefs/testgodefs_test.go b/misc/cgo/testgodefs/testgodefs_test.go
index 4c2312c1c8..aae3404360 100644
--- a/misc/cgo/testgodefs/testgodefs_test.go
+++ b/misc/cgo/testgodefs/testgodefs_test.go
@@ -6,7 +6,6 @@ package testgodefs
 
 import (
 	"bytes"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -34,7 +33,7 @@ func TestGoDefs(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	gopath, err := ioutil.TempDir("", "testgodefs-gopath")
+	gopath, err := os.MkdirTemp("", "testgodefs-gopath")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -58,20 +57,20 @@ func TestGoDefs(t *testing.T) {
 			t.Fatalf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, cmd.Stderr)
 		}
 
-		if err := ioutil.WriteFile(filepath.Join(dir, fp+"_defs.go"), out, 0644); err != nil {
+		if err := os.WriteFile(filepath.Join(dir, fp+"_defs.go"), out, 0644); err != nil {
 			t.Fatal(err)
 		}
 	}
 
-	main, err := ioutil.ReadFile(filepath.Join("testdata", "main.go"))
+	main, err := os.ReadFile(filepath.Join("testdata", "main.go"))
 	if err != nil {
 		t.Fatal(err)
 	}
-	if err := ioutil.WriteFile(filepath.Join(dir, "main.go"), main, 0644); err != nil {
+	if err := os.WriteFile(filepath.Join(dir, "main.go"), main, 0644); err != nil {
 		t.Fatal(err)
 	}
 
-	if err := ioutil.WriteFile(filepath.Join(dir, "go.mod"), []byte("module testgodefs\ngo 1.14\n"), 0644); err != nil {
+	if err := os.WriteFile(filepath.Join(dir, "go.mod"), []byte("module testgodefs\ngo 1.14\n"), 0644); err != nil {
 		t.Fatal(err)
 	}
 
diff --git a/misc/cgo/testplugin/plugin_test.go b/misc/cgo/testplugin/plugin_test.go
index 9055dbda04..28a8c669c0 100644
--- a/misc/cgo/testplugin/plugin_test.go
+++ b/misc/cgo/testplugin/plugin_test.go
@@ -9,7 +9,6 @@ import (
 	"context"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -31,15 +30,28 @@ func TestMain(m *testing.M) {
 	os.Exit(testMain(m))
 }
 
+// tmpDir is used to cleanup logged commands -- s/tmpDir/$TMPDIR/
+var tmpDir string
+
+// prettyPrintf prints lines with tmpDir sanitized.
+func prettyPrintf(format string, args ...interface{}) {
+	s := fmt.Sprintf(format, args...)
+	if tmpDir != "" {
+		s = strings.ReplaceAll(s, tmpDir, "$TMPDIR")
+	}
+	fmt.Print(s)
+}
+
 func testMain(m *testing.M) int {
 	// Copy testdata into GOPATH/src/testplugin, along with a go.mod file
 	// declaring the same path.
 
-	GOPATH, err := ioutil.TempDir("", "plugin_test")
+	GOPATH, err := os.MkdirTemp("", "plugin_test")
 	if err != nil {
 		log.Panic(err)
 	}
 	defer os.RemoveAll(GOPATH)
+	tmpDir = GOPATH
 
 	modRoot := filepath.Join(GOPATH, "src", "testplugin")
 	altRoot := filepath.Join(GOPATH, "alt", "src", "testplugin")
@@ -50,14 +62,20 @@ func testMain(m *testing.M) int {
 		if err := overlayDir(dstRoot, srcRoot); err != nil {
 			log.Panic(err)
 		}
-		if err := ioutil.WriteFile(filepath.Join(dstRoot, "go.mod"), []byte("module testplugin\n"), 0666); err != nil {
+		prettyPrintf("mkdir -p %s\n", dstRoot)
+		prettyPrintf("rsync -a %s/ %s\n", srcRoot, dstRoot)
+
+		if err := os.WriteFile(filepath.Join(dstRoot, "go.mod"), []byte("module testplugin\n"), 0666); err != nil {
 			log.Panic(err)
 		}
+		prettyPrintf("echo 'module testplugin' > %s/go.mod\n", dstRoot)
 	}
 
 	os.Setenv("GOPATH", filepath.Join(GOPATH, "alt"))
 	if err := os.Chdir(altRoot); err != nil {
 		log.Panic(err)
+	} else {
+		prettyPrintf("cd %s\n", altRoot)
 	}
 	os.Setenv("PWD", altRoot)
 	goCmd(nil, "build", "-buildmode=plugin", "-o", filepath.Join(modRoot, "plugin-mismatch.so"), "./plugin-mismatch")
@@ -65,6 +83,8 @@ func testMain(m *testing.M) int {
 	os.Setenv("GOPATH", GOPATH)
 	if err := os.Chdir(modRoot); err != nil {
 		log.Panic(err)
+	} else {
+		prettyPrintf("cd %s\n", modRoot)
 	}
 	os.Setenv("PWD", modRoot)
 
@@ -72,13 +92,14 @@ func testMain(m *testing.M) int {
 
 	goCmd(nil, "build", "-buildmode=plugin", "./plugin1")
 	goCmd(nil, "build", "-buildmode=plugin", "./plugin2")
-	so, err := ioutil.ReadFile("plugin2.so")
+	so, err := os.ReadFile("plugin2.so")
 	if err != nil {
 		log.Panic(err)
 	}
-	if err := ioutil.WriteFile("plugin2-dup.so", so, 0444); err != nil {
+	if err := os.WriteFile("plugin2-dup.so", so, 0444); err != nil {
 		log.Panic(err)
 	}
+	prettyPrintf("cp plugin2.so plugin2-dup.so\n")
 
 	goCmd(nil, "build", "-buildmode=plugin", "-o=sub/plugin1.so", "./sub/plugin1")
 	goCmd(nil, "build", "-buildmode=plugin", "-o=unnamed1.so", "./unnamed1/main.go")
@@ -95,8 +116,53 @@ func goCmd(t *testing.T, op string, args ...string) {
 	run(t, "go", append([]string{op, "-gcflags", gcflags}, args...)...)
 }
 
+// escape converts a string to something suitable for a shell command line.
+func escape(s string) string {
+	s = strings.Replace(s, "\\", "\\\\", -1)
+	s = strings.Replace(s, "'", "\\'", -1)
+	// Conservative guess at characters that will force quoting
+	if s == "" || strings.ContainsAny(s, "\\ ;#*&$~?!|[]()<>{}`") {
+		s = "'" + s + "'"
+	}
+	return s
+}
+
+// asCommandLine renders cmd as something that could be copy-and-pasted into a command line
+func asCommandLine(cwd string, cmd *exec.Cmd) string {
+	s := "("
+	if cmd.Dir != "" && cmd.Dir != cwd {
+		s += "cd" + escape(cmd.Dir) + ";"
+	}
+	for _, e := range cmd.Env {
+		if !strings.HasPrefix(e, "PATH=") &&
+			!strings.HasPrefix(e, "HOME=") &&
+			!strings.HasPrefix(e, "USER=") &&
+			!strings.HasPrefix(e, "SHELL=") {
+			s += " "
+			s += escape(e)
+		}
+	}
+	// These EVs are relevant to this test.
+	for _, e := range os.Environ() {
+		if strings.HasPrefix(e, "PWD=") ||
+			strings.HasPrefix(e, "GOPATH=") ||
+			strings.HasPrefix(e, "LD_LIBRARY_PATH=") {
+			s += " "
+			s += escape(e)
+		}
+	}
+	for _, a := range cmd.Args {
+		s += " "
+		s += escape(a)
+	}
+	s += " )"
+	return s
+}
+
 func run(t *testing.T, bin string, args ...string) string {
 	cmd := exec.Command(bin, args...)
+	cmdLine := asCommandLine(".", cmd)
+	prettyPrintf("%s\n", cmdLine)
 	cmd.Stderr = new(strings.Builder)
 	out, err := cmd.Output()
 	if err != nil {
@@ -201,12 +267,18 @@ func TestMethod(t *testing.T) {
 	// Exported symbol's method must be live.
 	goCmd(t, "build", "-buildmode=plugin", "-o", "plugin.so", "./method/plugin.go")
 	goCmd(t, "build", "-o", "method.exe", "./method/main.go")
+	run(t, "./method.exe")
+}
 
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-	defer cancel()
-	cmd := exec.CommandContext(ctx, "./method.exe")
-	out, err := cmd.CombinedOutput()
-	if err != nil {
-		t.Fatalf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, out)
-	}
+func TestMethod2(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-o", "method2.so", "./method2/plugin.go")
+	goCmd(t, "build", "-o", "method2.exe", "./method2/main.go")
+	run(t, "./method2.exe")
+}
+
+func TestIssue44956(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-o", "issue44956p1.so", "./issue44956/plugin1.go")
+	goCmd(t, "build", "-buildmode=plugin", "-o", "issue44956p2.so", "./issue44956/plugin2.go")
+	goCmd(t, "build", "-o", "issue44956.exe", "./issue44956/main.go")
+	run(t, "./issue44956.exe")
 }
diff --git a/misc/cgo/testplugin/testdata/issue44956/base/base.go b/misc/cgo/testplugin/testdata/issue44956/base/base.go
new file mode 100644
index 0000000000..609aa0dff4
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/issue44956/base/base.go
@@ -0,0 +1,7 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package base
+
+var X = &map[int]int{123: 456}
diff --git a/misc/cgo/testplugin/testdata/issue44956/main.go b/misc/cgo/testplugin/testdata/issue44956/main.go
new file mode 100644
index 0000000000..287a60585e
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/issue44956/main.go
@@ -0,0 +1,47 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 44956: writable static temp is not exported correctly.
+// In the test below, package base is
+//
+//     X = &map{...}
+//
+// which compiles to
+//
+//     X = &stmp           // static
+//     stmp = makemap(...) // in init function
+//
+// plugin1 and plugin2 both import base. plugin1 doesn't use
+// base.X, so that symbol is deadcoded in plugin1.
+//
+// plugin1 is loaded first. base.init runs at that point, which
+// initialize base.stmp.
+//
+// plugin2 is then loaded. base.init already ran, so it doesn't run
+// again. When base.stmp is not exported, plugin2's base.X points to
+// its own private base.stmp, which is not initialized, fail.
+
+package main
+
+import "plugin"
+
+func main() {
+	_, err := plugin.Open("issue44956p1.so")
+	if err != nil {
+		panic("FAIL")
+	}
+
+	p2, err := plugin.Open("issue44956p2.so")
+	if err != nil {
+		panic("FAIL")
+	}
+	f, err := p2.Lookup("F")
+	if err != nil {
+		panic("FAIL")
+	}
+	x := f.(func() *map[int]int)()
+	if x == nil || (*x)[123] != 456 {
+		panic("FAIL")
+	}
+}
diff --git a/misc/cgo/testplugin/testdata/issue44956/plugin1.go b/misc/cgo/testplugin/testdata/issue44956/plugin1.go
new file mode 100644
index 0000000000..499fa31abf
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/issue44956/plugin1.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import _ "testplugin/issue44956/base"
+
+func main() {}
diff --git a/misc/cgo/testplugin/testdata/issue44956/plugin2.go b/misc/cgo/testplugin/testdata/issue44956/plugin2.go
new file mode 100644
index 0000000000..a73542ca71
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/issue44956/plugin2.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "testplugin/issue44956/base"
+
+func F() *map[int]int { return base.X }
+
+func main() {}
diff --git a/misc/cgo/testplugin/testdata/method2/main.go b/misc/cgo/testplugin/testdata/method2/main.go
new file mode 100644
index 0000000000..89afbda3d4
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/method2/main.go
@@ -0,0 +1,32 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// A type can be passed to a plugin and converted to interface
+// there. So its methods need to be live.
+
+package main
+
+import (
+	"plugin"
+
+	"testplugin/method2/p"
+)
+
+var t p.T
+
+type I interface{ M() }
+
+func main() {
+	pl, err := plugin.Open("method2.so")
+	if err != nil {
+		panic(err)
+	}
+
+	f, err := pl.Lookup("F")
+	if err != nil {
+		panic(err)
+	}
+
+	f.(func(p.T) interface{})(t).(I).M()
+}
diff --git a/misc/cgo/testplugin/testdata/method2/p/p.go b/misc/cgo/testplugin/testdata/method2/p/p.go
new file mode 100644
index 0000000000..acb526acec
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/method2/p/p.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+type T int
+
+func (T) M() { println("M") }
diff --git a/misc/cgo/testplugin/testdata/method2/plugin.go b/misc/cgo/testplugin/testdata/method2/plugin.go
new file mode 100644
index 0000000000..6198e7648e
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/method2/plugin.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "testplugin/method2/p"
+
+func main() {}
+
+func F(t p.T) interface{} { return t }
diff --git a/misc/cgo/testsanitizers/cc_test.go b/misc/cgo/testsanitizers/cc_test.go
index 0192a663dd..384b6250e1 100644
--- a/misc/cgo/testsanitizers/cc_test.go
+++ b/misc/cgo/testsanitizers/cc_test.go
@@ -11,7 +11,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -36,7 +35,7 @@ func requireOvercommit(t *testing.T) {
 
 	overcommit.Once.Do(func() {
 		var out []byte
-		out, overcommit.err = ioutil.ReadFile("/proc/sys/vm/overcommit_memory")
+		out, overcommit.err = os.ReadFile("/proc/sys/vm/overcommit_memory")
 		if overcommit.err != nil {
 			return
 		}
@@ -313,14 +312,14 @@ int main() {
 `)
 
 func (c *config) checkCSanitizer() (skip bool, err error) {
-	dir, err := ioutil.TempDir("", c.sanitizer)
+	dir, err := os.MkdirTemp("", c.sanitizer)
 	if err != nil {
 		return false, fmt.Errorf("failed to create temp directory: %v", err)
 	}
 	defer os.RemoveAll(dir)
 
 	src := filepath.Join(dir, "return0.c")
-	if err := ioutil.WriteFile(src, cMain, 0600); err != nil {
+	if err := os.WriteFile(src, cMain, 0600); err != nil {
 		return false, fmt.Errorf("failed to write C source file: %v", err)
 	}
 
@@ -418,7 +417,7 @@ func (d *tempDir) Join(name string) string {
 
 func newTempDir(t *testing.T) *tempDir {
 	t.Helper()
-	dir, err := ioutil.TempDir("", filepath.Dir(t.Name()))
+	dir, err := os.MkdirTemp("", filepath.Dir(t.Name()))
 	if err != nil {
 		t.Fatalf("Failed to create temp dir: %v", err)
 	}
@@ -440,3 +439,14 @@ func hangProneCmd(name string, arg ...string) *exec.Cmd {
 	}
 	return cmd
 }
+
+// mSanSupported is a copy of the function cmd/internal/sys.MSanSupported,
+// because the internal pacakage can't be used here.
+func mSanSupported(goos, goarch string) bool {
+	switch goos {
+	case "linux":
+		return goarch == "amd64" || goarch == "arm64"
+	default:
+		return false
+	}
+}
diff --git a/misc/cgo/testsanitizers/cshared_test.go b/misc/cgo/testsanitizers/cshared_test.go
index 56063ea620..8fd03715a1 100644
--- a/misc/cgo/testsanitizers/cshared_test.go
+++ b/misc/cgo/testsanitizers/cshared_test.go
@@ -6,7 +6,7 @@ package sanitizers_test
 
 import (
 	"fmt"
-	"io/ioutil"
+	"os"
 	"strings"
 	"testing"
 )
@@ -19,6 +19,12 @@ func TestShared(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+
+	GOARCH, err := goEnv("GOARCH")
+	if err != nil {
+		t.Fatal(err)
+	}
+
 	libExt := "so"
 	if GOOS == "darwin" {
 		libExt = "dylib"
@@ -41,6 +47,11 @@ func TestShared(t *testing.T) {
 	for _, tc := range cases {
 		tc := tc
 		name := strings.TrimSuffix(tc.src, ".go")
+		//The memory sanitizer tests require support for the -msan option.
+		if tc.sanitizer == "memory" && !mSanSupported(GOOS, GOARCH) {
+			t.Logf("skipping %s test on %s/%s; -msan option is not supported.", name, GOOS, GOARCH)
+			continue
+		}
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			config := configure(tc.sanitizer)
@@ -53,7 +64,7 @@ func TestShared(t *testing.T) {
 			mustRun(t, config.goCmd("build", "-buildmode=c-shared", "-o", lib, srcPath(tc.src)))
 
 			cSrc := dir.Join("main.c")
-			if err := ioutil.WriteFile(cSrc, cMain, 0600); err != nil {
+			if err := os.WriteFile(cSrc, cMain, 0600); err != nil {
 				t.Fatalf("failed to write C source file: %v", err)
 			}
 
diff --git a/misc/cgo/testsanitizers/msan_test.go b/misc/cgo/testsanitizers/msan_test.go
index 5e2f9759ba..2a3494fbfc 100644
--- a/misc/cgo/testsanitizers/msan_test.go
+++ b/misc/cgo/testsanitizers/msan_test.go
@@ -10,6 +10,19 @@ import (
 )
 
 func TestMSAN(t *testing.T) {
+	goos, err := goEnv("GOOS")
+	if err != nil {
+		t.Fatal(err)
+	}
+	goarch, err := goEnv("GOARCH")
+	if err != nil {
+		t.Fatal(err)
+	}
+	// The msan tests require support for the -msan option.
+	if !mSanSupported(goos, goarch) {
+		t.Skipf("skipping on %s/%s; -msan option is not supported.", goos, goarch)
+	}
+
 	t.Parallel()
 	requireOvercommit(t)
 	config := configure("memory")
diff --git a/misc/cgo/testsanitizers/testdata/tsan9.go b/misc/cgo/testsanitizers/testdata/tsan9.go
index f166d8b495..06304be751 100644
--- a/misc/cgo/testsanitizers/testdata/tsan9.go
+++ b/misc/cgo/testsanitizers/testdata/tsan9.go
@@ -44,7 +44,7 @@ void spin() {
 import "C"
 
 import (
-	"io/ioutil"
+	"io"
 	"runtime/pprof"
 	"time"
 )
@@ -60,7 +60,7 @@ func goSpin() {
 }
 
 func main() {
-	pprof.StartCPUProfile(ioutil.Discard)
+	pprof.StartCPUProfile(io.Discard)
 	go C.spin()
 	goSpin()
 	pprof.StopCPUProfile()
diff --git a/misc/cgo/testshared/shared_test.go b/misc/cgo/testshared/shared_test.go
index f52391c6f6..e77f848915 100644
--- a/misc/cgo/testshared/shared_test.go
+++ b/misc/cgo/testshared/shared_test.go
@@ -13,7 +13,6 @@ import (
 	"fmt"
 	"go/build"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -90,7 +89,7 @@ func goCmd(t *testing.T, args ...string) string {
 
 // TestMain calls testMain so that the latter can use defer (TestMain exits with os.Exit).
 func testMain(m *testing.M) (int, error) {
-	workDir, err := ioutil.TempDir("", "shared_test")
+	workDir, err := os.MkdirTemp("", "shared_test")
 	if err != nil {
 		return 0, err
 	}
@@ -177,7 +176,7 @@ func cloneTestdataModule(gopath string) (string, error) {
 	if err := overlayDir(modRoot, "testdata"); err != nil {
 		return "", err
 	}
-	if err := ioutil.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module testshared\n"), 0644); err != nil {
+	if err := os.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module testshared\n"), 0644); err != nil {
 		return "", err
 	}
 	return modRoot, nil
@@ -318,7 +317,7 @@ func TestShlibnameFiles(t *testing.T) {
 	}
 	for _, pkg := range pkgs {
 		shlibnamefile := filepath.Join(gorootInstallDir, pkg+".shlibname")
-		contentsb, err := ioutil.ReadFile(shlibnamefile)
+		contentsb, err := os.ReadFile(shlibnamefile)
 		if err != nil {
 			t.Errorf("error reading shlibnamefile for %s: %v", pkg, err)
 			continue
@@ -791,7 +790,7 @@ func resetFileStamps() {
 // It also sets the time of the file, so that we can see if it is rewritten.
 func touch(t *testing.T, path string) (cleanup func()) {
 	t.Helper()
-	data, err := ioutil.ReadFile(path)
+	data, err := os.ReadFile(path)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -837,14 +836,14 @@ func touch(t *testing.T, path string) (cleanup func()) {
 	// user-writable.
 	perm := fi.Mode().Perm() | 0200
 
-	if err := ioutil.WriteFile(path, data, perm); err != nil {
+	if err := os.WriteFile(path, data, perm); err != nil {
 		t.Fatal(err)
 	}
 	if err := os.Chtimes(path, nearlyNew, nearlyNew); err != nil {
 		t.Fatal(err)
 	}
 	return func() {
-		if err := ioutil.WriteFile(path, old, perm); err != nil {
+		if err := os.WriteFile(path, old, perm); err != nil {
 			t.Fatal(err)
 		}
 	}
diff --git a/misc/cgo/testshared/testdata/depBase/asm.s b/misc/cgo/testshared/testdata/depBase/asm.s
index a8acf77f0b..0f1111f392 100644
--- a/misc/cgo/testshared/testdata/depBase/asm.s
+++ b/misc/cgo/testshared/testdata/depBase/asm.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo
+// +build gc
 
 #include "textflag.h"
 
diff --git a/misc/cgo/testshared/testdata/depBase/stubs.go b/misc/cgo/testshared/testdata/depBase/stubs.go
index 04534f38dd..c77953803b 100644
--- a/misc/cgo/testshared/testdata/depBase/stubs.go
+++ b/misc/cgo/testshared/testdata/depBase/stubs.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo
+// +build gc
 
 package depBase
 
diff --git a/misc/cgo/testso/so_test.go b/misc/cgo/testso/so_test.go
index 57f0fd34f7..2023c51f11 100644
--- a/misc/cgo/testso/so_test.go
+++ b/misc/cgo/testso/so_test.go
@@ -7,7 +7,6 @@
 package so_test
 
 import (
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -37,7 +36,7 @@ func requireTestSOSupported(t *testing.T) {
 func TestSO(t *testing.T) {
 	requireTestSOSupported(t)
 
-	GOPATH, err := ioutil.TempDir("", "cgosotest")
+	GOPATH, err := os.MkdirTemp("", "cgosotest")
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -47,7 +46,7 @@ func TestSO(t *testing.T) {
 	if err := overlayDir(modRoot, "testdata"); err != nil {
 		log.Panic(err)
 	}
-	if err := ioutil.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgosotest\n"), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgosotest\n"), 0666); err != nil {
 		log.Panic(err)
 	}
 
@@ -80,6 +79,10 @@ func TestSO(t *testing.T) {
 	case "windows":
 		ext = "dll"
 		args = append(args, "-DEXPORT_DLL")
+		// At least in mingw-clang it is not permitted to just name a .dll
+		// on the command line. You must name the corresponding import
+		// library instead, even though the dll is used when the executable is run.
+		args = append(args, "-Wl,-out-implib,libcgosotest.a")
 	case "aix":
 		ext = "so.1"
 	}
diff --git a/misc/cgo/testso/testdata/cgoso.go b/misc/cgo/testso/testdata/cgoso.go
index bba5de3312..b59b2a8e8b 100644
--- a/misc/cgo/testso/testdata/cgoso.go
+++ b/misc/cgo/testso/testdata/cgoso.go
@@ -14,7 +14,7 @@ package cgosotest
 #cgo solaris LDFLAGS: -L. -lcgosotest
 #cgo netbsd LDFLAGS: -L. libcgosotest.so
 #cgo darwin LDFLAGS: -L. libcgosotest.dylib
-#cgo windows LDFLAGS: -L. libcgosotest.dll
+#cgo windows LDFLAGS: -L. libcgosotest.a
 #cgo aix LDFLAGS: -L. -l cgosotest
 
 void init(void);
diff --git a/misc/cgo/testsovar/so_test.go b/misc/cgo/testsovar/so_test.go
index 57f0fd34f7..2023c51f11 100644
--- a/misc/cgo/testsovar/so_test.go
+++ b/misc/cgo/testsovar/so_test.go
@@ -7,7 +7,6 @@
 package so_test
 
 import (
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -37,7 +36,7 @@ func requireTestSOSupported(t *testing.T) {
 func TestSO(t *testing.T) {
 	requireTestSOSupported(t)
 
-	GOPATH, err := ioutil.TempDir("", "cgosotest")
+	GOPATH, err := os.MkdirTemp("", "cgosotest")
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -47,7 +46,7 @@ func TestSO(t *testing.T) {
 	if err := overlayDir(modRoot, "testdata"); err != nil {
 		log.Panic(err)
 	}
-	if err := ioutil.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgosotest\n"), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgosotest\n"), 0666); err != nil {
 		log.Panic(err)
 	}
 
@@ -80,6 +79,10 @@ func TestSO(t *testing.T) {
 	case "windows":
 		ext = "dll"
 		args = append(args, "-DEXPORT_DLL")
+		// At least in mingw-clang it is not permitted to just name a .dll
+		// on the command line. You must name the corresponding import
+		// library instead, even though the dll is used when the executable is run.
+		args = append(args, "-Wl,-out-implib,libcgosotest.a")
 	case "aix":
 		ext = "so.1"
 	}
diff --git a/misc/cgo/testsovar/testdata/cgoso.go b/misc/cgo/testsovar/testdata/cgoso.go
index 9c7f95e92e..d9deb556da 100644
--- a/misc/cgo/testsovar/testdata/cgoso.go
+++ b/misc/cgo/testsovar/testdata/cgoso.go
@@ -18,7 +18,7 @@ package cgosotest
 #cgo solaris LDFLAGS: -L. -lcgosotest
 #cgo netbsd LDFLAGS: -L. libcgosotest.so
 #cgo darwin LDFLAGS: -L. libcgosotest.dylib
-#cgo windows LDFLAGS: -L. libcgosotest.dll
+#cgo windows LDFLAGS: -L. libcgosotest.a
 #cgo aix LDFLAGS: -L. -l cgosotest
 
 #include "cgoso_c.h"
diff --git a/misc/chrome/gophertool/popup.html b/misc/chrome/gophertool/popup.html
index 9740406276..ad42a3847c 100644
--- a/misc/chrome/gophertool/popup.html
+++ b/misc/chrome/gophertool/popup.html
@@ -15,7 +15,7 @@
 <a href="#" url="https://golang.org/pkg/">pkg</a> id/name:</small>
 <form style='margin: 0' id='navform'><nobr><input id="inputbox" size=10 tabindex=1 /><input type="submit" value="go" /></nobr></form>
 <small>Also: <a href="#" url="https://build.golang.org">buildbots</a>
-<a href="#" url="https://github.com/golang/go">Github</a>
+<a href="#" url="https://github.com/golang/go">GitHub</a>
 </small>
 </body>
 </html>
diff --git a/misc/ios/detect.go b/misc/ios/detect.go
index d32bcc3202..cde5723892 100644
--- a/misc/ios/detect.go
+++ b/misc/ios/detect.go
@@ -16,7 +16,6 @@ import (
 	"bytes"
 	"crypto/x509"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"strings"
@@ -38,7 +37,7 @@ func main() {
 	fmt.Println("# will be overwritten when running Go programs.")
 	for _, mp := range mps {
 		fmt.Println()
-		f, err := ioutil.TempFile("", "go_ios_detect_")
+		f, err := os.CreateTemp("", "go_ios_detect_")
 		check(err)
 		fname := f.Name()
 		defer os.Remove(fname)
diff --git a/misc/ios/go_ios_exec.go b/misc/ios/go_ios_exec.go
index 0acf1b259c..9e63717d92 100644
--- a/misc/ios/go_ios_exec.go
+++ b/misc/ios/go_ios_exec.go
@@ -26,7 +26,6 @@ import (
 	"fmt"
 	"go/build"
 	"io"
-	"io/ioutil"
 	"log"
 	"net"
 	"os"
@@ -79,7 +78,7 @@ func main() {
 
 func runMain() (int, error) {
 	var err error
-	tmpdir, err = ioutil.TempDir("", "go_ios_exec_")
+	tmpdir, err = os.MkdirTemp("", "go_ios_exec_")
 	if err != nil {
 		return 1, err
 	}
@@ -205,13 +204,13 @@ func assembleApp(appdir, bin string) error {
 	}
 
 	entitlementsPath := filepath.Join(tmpdir, "Entitlements.plist")
-	if err := ioutil.WriteFile(entitlementsPath, []byte(entitlementsPlist()), 0744); err != nil {
+	if err := os.WriteFile(entitlementsPath, []byte(entitlementsPlist()), 0744); err != nil {
 		return err
 	}
-	if err := ioutil.WriteFile(filepath.Join(appdir, "Info.plist"), []byte(infoPlist(pkgpath)), 0744); err != nil {
+	if err := os.WriteFile(filepath.Join(appdir, "Info.plist"), []byte(infoPlist(pkgpath)), 0744); err != nil {
 		return err
 	}
-	if err := ioutil.WriteFile(filepath.Join(appdir, "ResourceRules.plist"), []byte(resourceRules), 0744); err != nil {
+	if err := os.WriteFile(filepath.Join(appdir, "ResourceRules.plist"), []byte(resourceRules), 0744); err != nil {
 		return err
 	}
 	return nil
diff --git a/misc/linkcheck/linkcheck.go b/misc/linkcheck/linkcheck.go
index d9bfd2f767..570b430da4 100644
--- a/misc/linkcheck/linkcheck.go
+++ b/misc/linkcheck/linkcheck.go
@@ -11,7 +11,7 @@ import (
 	"errors"
 	"flag"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"log"
 	"net/http"
 	"os"
@@ -144,7 +144,7 @@ func doCrawl(url string) error {
 	if res.StatusCode != 200 {
 		return errors.New(res.Status)
 	}
-	slurp, err := ioutil.ReadAll(res.Body)
+	slurp, err := io.ReadAll(res.Body)
 	res.Body.Close()
 	if err != nil {
 		log.Fatalf("Error reading %s body: %v", url, err)
diff --git a/misc/reboot/experiment_toolid_test.go b/misc/reboot/experiment_toolid_test.go
index eabf06b19e..4f40284d80 100644
--- a/misc/reboot/experiment_toolid_test.go
+++ b/misc/reboot/experiment_toolid_test.go
@@ -13,7 +13,6 @@ package reboot_test
 
 import (
 	"bytes"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -23,7 +22,7 @@ import (
 
 func TestExperimentToolID(t *testing.T) {
 	// Set up GOROOT
-	goroot, err := ioutil.TempDir("", "experiment-goroot")
+	goroot, err := os.MkdirTemp("", "experiment-goroot")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -34,13 +33,13 @@ func TestExperimentToolID(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if err := ioutil.WriteFile(filepath.Join(goroot, "VERSION"), []byte("go1.999"), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(goroot, "VERSION"), []byte("go1.999"), 0666); err != nil {
 		t.Fatal(err)
 	}
 	env := append(os.Environ(), "GOROOT=", "GOROOT_BOOTSTRAP="+runtime.GOROOT())
 
 	// Use a clean cache.
-	gocache, err := ioutil.TempDir("", "experiment-gocache")
+	gocache, err := os.MkdirTemp("", "experiment-gocache")
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/misc/reboot/reboot_test.go b/misc/reboot/reboot_test.go
index 717c0fb709..6bafc608b5 100644
--- a/misc/reboot/reboot_test.go
+++ b/misc/reboot/reboot_test.go
@@ -7,7 +7,6 @@
 package reboot_test
 
 import (
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -16,7 +15,7 @@ import (
 )
 
 func TestRepeatBootstrap(t *testing.T) {
-	goroot, err := ioutil.TempDir("", "reboot-goroot")
+	goroot, err := os.MkdirTemp("", "reboot-goroot")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -27,7 +26,7 @@ func TestRepeatBootstrap(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if err := ioutil.WriteFile(filepath.Join(goroot, "VERSION"), []byte(runtime.Version()), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(goroot, "VERSION"), []byte(runtime.Version()), 0666); err != nil {
 		t.Fatal(err)
 	}
 
diff --git a/misc/trace/trace_viewer_full.html b/misc/trace/trace_viewer_full.html
index ef2e0ea573..ae6e35fca2 100644
--- a/misc/trace/trace_viewer_full.html
+++ b/misc/trace/trace_viewer_full.html
@@ -993,13 +993,13 @@
     </style>
     <div style="padding-right: 200px">
       <div style="float:right;  border-style: solid; border-width: 1px; padding:20px">
-        X no feedback<br/>
-        0 uninitialized<br/>
-        . premonomorphic<br/>
-        1 monomorphic<br/>
-        ^ recompute handler<br/>
-        P polymorphic<br/>
-        N megamorphic<br/>
+        X no feedback<br>
+        0 uninitialized<br>
+        . premonomorphic<br>
+        1 monomorphic<br>
+        ^ recompute handler<br>
+        P polymorphic<br>
+        N megamorphic<br>
         G generic
       </div>
     </div>
@@ -3596,7 +3596,7 @@
     <div id="pipeline_per_frame_container">
       <div class="subtitle">Graphics Pipeline and Raster Tasks</div>
       <div class="description">
-        When raster tasks are completed in comparison to the rest of the graphics pipeline.<br/>
+        When raster tasks are completed in comparison to the rest of the graphics pipeline.<br>
         Only pages where raster tasks are completed after beginFrame is issued are included.
       </div>
       <tr-v-ui-raster-visualization id="rasterVisualization">
diff --git a/misc/wasm/wasm_exec.js b/misc/wasm/wasm_exec.js
index 82041e6bb9..3e41e628ef 100644
--- a/misc/wasm/wasm_exec.js
+++ b/misc/wasm/wasm_exec.js
@@ -296,8 +296,8 @@
 						setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000);
 					},
 
-					// func walltime1() (sec int64, nsec int32)
-					"runtime.walltime1": (sp) => {
+					// func walltime() (sec int64, nsec int32)
+					"runtime.walltime": (sp) => {
 						sp >>>= 0;
 						const msec = (new Date).getTime();
 						setInt64(sp + 8, msec / 1000);