all: replace package ioutil with os and io in src

For #45557

Change-Id: I56824135d86452603dd4ed4bab0e24c201bb0683
Reviewed-on: https://go-review.googlesource.com/c/go/+/426257
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Andy Pan <panjf2000@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>

15 files changed, 62 insertions, 72 deletions

diff --git a/src/cmd/internal/archive/archive_test.go b/src/cmd/internal/archive/archive_test.go
index bbaa72cbf8..cca65af8ed 100644
--- a/src/cmd/internal/archive/archive_test.go
+++ b/src/cmd/internal/archive/archive_test.go
@@ -13,7 +13,6 @@ import (
 	"internal/testenv"
 	"internal/xcoff"
 	"io"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -43,12 +42,12 @@ func copyDir(dst, src string) error {
 	if err != nil {
 		return err
 	}
-	fis, err := ioutil.ReadDir(src)
+	entries, err := os.ReadDir(src)
 	if err != nil {
 		return err
 	}
-	for _, fi := range fis {
-		err = copyFile(filepath.Join(dst, fi.Name()), filepath.Join(src, fi.Name()))
+	for _, entry := range entries {
+		err = copyFile(filepath.Join(dst, entry.Name()), filepath.Join(src, entry.Name()))
 		if err != nil {
 			return err
 		}
@@ -96,7 +95,7 @@ type goobjPaths struct {
 func buildGoobj(t *testing.T) goobjPaths {
 	buildOnce.Do(func() {
 		buildErr = func() (err error) {
-			buildDir, err = ioutil.TempDir("", "TestGoobj")
+			buildDir, err = os.MkdirTemp("", "TestGoobj")
 			if err != nil {
 				return err
 			}
@@ -132,7 +131,7 @@ func buildGoobj(t *testing.T) goobjPaths {
 				gopath := filepath.Join(buildDir, "gopath")
 				err = copyDir(filepath.Join(gopath, "src", "mycgo"), filepath.Join("testdata", "mycgo"))
 				if err == nil {
-					err = ioutil.WriteFile(filepath.Join(gopath, "src", "mycgo", "go.mod"), []byte("module mycgo\n"), 0666)
+					err = os.WriteFile(filepath.Join(gopath, "src", "mycgo", "go.mod"), []byte("module mycgo\n"), 0666)
 				}
 				if err != nil {
 					return err
diff --git a/src/cmd/internal/buildid/buildid_test.go b/src/cmd/internal/buildid/buildid_test.go
index f04e328046..55835bf8ac 100644
--- a/src/cmd/internal/buildid/buildid_test.go
+++ b/src/cmd/internal/buildid/buildid_test.go
@@ -8,7 +8,6 @@ import (
 	"bytes"
 	"crypto/sha256"
 	"internal/obscuretestdata"
-	"io/ioutil"
 	"os"
 	"reflect"
 	"strings"
@@ -21,7 +20,7 @@ const (
 )
 
 func TestReadFile(t *testing.T) {
-	f, err := ioutil.TempFile("", "buildid-test-")
+	f, err := os.CreateTemp("", "buildid-test-")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -59,7 +58,7 @@ func TestReadFile(t *testing.T) {
 			t.Errorf("ReadFile(%s) [readSize=2k] = %q, %v, want %q, nil", f, id, err, expectedID)
 		}
 
-		data, err := ioutil.ReadFile(f)
+		data, err := os.ReadFile(f)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -68,7 +67,7 @@ func TestReadFile(t *testing.T) {
 			t.Errorf("FindAndHash(%s): %v", f, err)
 			continue
 		}
-		if err := ioutil.WriteFile(tmp, data, 0666); err != nil {
+		if err := os.WriteFile(tmp, data, 0666); err != nil {
 			t.Error(err)
 			continue
 		}
diff --git a/src/cmd/internal/goobj/mkbuiltin.go b/src/cmd/internal/goobj/mkbuiltin.go
index d9db63ad44..d96ac41c1a 100644
--- a/src/cmd/internal/goobj/mkbuiltin.go
+++ b/src/cmd/internal/goobj/mkbuiltin.go
@@ -18,7 +18,6 @@ import (
 	"go/parser"
 	"go/token"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 	"path/filepath"
@@ -44,7 +43,7 @@ func main() {
 	if *stdout {
 		_, err = os.Stdout.Write(out)
 	} else {
-		err = ioutil.WriteFile("builtinlist.go", out, 0666)
+		err = os.WriteFile("builtinlist.go", out, 0666)
 	}
 	if err != nil {
 		log.Fatal(err)
diff --git a/src/cmd/internal/goobj/objfile_test.go b/src/cmd/internal/goobj/objfile_test.go
index ed942aa934..d7eb0b194b 100644
--- a/src/cmd/internal/goobj/objfile_test.go
+++ b/src/cmd/internal/goobj/objfile_test.go
@@ -7,15 +7,15 @@ package goobj
 import (
 	"bufio"
 	"bytes"
-	"cmd/internal/bio"
-	"cmd/internal/objabi"
 	"fmt"
 	"internal/buildcfg"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"testing"
+
+	"cmd/internal/bio"
+	"cmd/internal/objabi"
 )
 
 func dummyWriter(buf *bytes.Buffer) *Writer {
@@ -97,7 +97,7 @@ func TestIssue41621LargeNumberOfRelocations(t *testing.T) {
 	}
 	testenv.MustHaveGoBuild(t)
 
-	tmpdir, err := ioutil.TempDir("", "lotsofrelocs")
+	tmpdir, err := os.MkdirTemp("", "lotsofrelocs")
 	if err != nil {
 		t.Fatalf("can't create temp directory: %v\n", err)
 	}
@@ -110,7 +110,7 @@ func TestIssue41621LargeNumberOfRelocations(t *testing.T) {
 		fmt.Fprintf(&w, "\t\"%d\",\n", i)
 	}
 	fmt.Fprintf(&w, issue41621epilog)
-	err = ioutil.WriteFile(tmpdir+"/large.go", w.Bytes(), 0666)
+	err = os.WriteFile(tmpdir+"/large.go", w.Bytes(), 0666)
 	if err != nil {
 		t.Fatalf("can't write output: %v\n", err)
 	}
@@ -118,7 +118,7 @@ func TestIssue41621LargeNumberOfRelocations(t *testing.T) {
 	// Emit go.mod
 	w.Reset()
 	fmt.Fprintf(&w, "module issue41621\n\ngo 1.12\n")
-	err = ioutil.WriteFile(tmpdir+"/go.mod", w.Bytes(), 0666)
+	err = os.WriteFile(tmpdir+"/go.mod", w.Bytes(), 0666)
 	if err != nil {
 		t.Fatalf("can't write output: %v\n", err)
 	}
diff --git a/src/cmd/internal/moddeps/moddeps_test.go b/src/cmd/internal/moddeps/moddeps_test.go
index 053cb8f548..26673937a0 100644
--- a/src/cmd/internal/moddeps/moddeps_test.go
+++ b/src/cmd/internal/moddeps/moddeps_test.go
@@ -11,7 +11,6 @@ import (
 	"internal/testenv"
 	"io"
 	"io/fs"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -361,7 +360,7 @@ func TestDependencyVersionsConsistent(t *testing.T) {
 		// It's ok if there are undetected differences in modules that do not
 		// provide imported packages: we will not have to pull in any backports of
 		// fixes to those modules anyway.
-		vendor, err := ioutil.ReadFile(filepath.Join(m.Dir, "vendor", "modules.txt"))
+		vendor, err := os.ReadFile(filepath.Join(m.Dir, "vendor", "modules.txt"))
 		if err != nil {
 			t.Error(err)
 			continue
diff --git a/src/cmd/internal/obj/arm64/asm_arm64_test.go b/src/cmd/internal/obj/arm64/asm_arm64_test.go
index f468b6b0fe..b1db336a33 100644
--- a/src/cmd/internal/obj/arm64/asm_arm64_test.go
+++ b/src/cmd/internal/obj/arm64/asm_arm64_test.go
@@ -8,7 +8,6 @@ import (
 	"bytes"
 	"fmt"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -27,7 +26,7 @@ func TestLarge(t *testing.T) {
 	}
 	testenv.MustHaveGoBuild(t)
 
-	dir, err := ioutil.TempDir("", "testlarge")
+	dir, err := os.MkdirTemp("", "testlarge")
 	if err != nil {
 		t.Fatalf("could not create directory: %v", err)
 	}
@@ -38,7 +37,7 @@ func TestLarge(t *testing.T) {
 	gen(buf)
 
 	tmpfile := filepath.Join(dir, "x.s")
-	err = ioutil.WriteFile(tmpfile, buf.Bytes(), 0644)
+	err = os.WriteFile(tmpfile, buf.Bytes(), 0644)
 	if err != nil {
 		t.Fatalf("can't write output: %v\n", err)
 	}
@@ -86,13 +85,13 @@ func gen(buf *bytes.Buffer) {
 
 // Issue 20348.
 func TestNoRet(t *testing.T) {
-	dir, err := ioutil.TempDir("", "testnoret")
+	dir, err := os.MkdirTemp("", "testnoret")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer os.RemoveAll(dir)
 	tmpfile := filepath.Join(dir, "x.s")
-	if err := ioutil.WriteFile(tmpfile, []byte("TEXT ·stub(SB),$0-0\nNOP\n"), 0644); err != nil {
+	if err := os.WriteFile(tmpfile, []byte("TEXT ·stub(SB),$0-0\nNOP\n"), 0644); err != nil {
 		t.Fatal(err)
 	}
 	cmd := exec.Command(testenv.GoToolPath(t), "tool", "asm", "-o", filepath.Join(dir, "x.o"), tmpfile)
@@ -106,7 +105,7 @@ func TestNoRet(t *testing.T) {
 // code can be aligned to the alignment value.
 func TestPCALIGN(t *testing.T) {
 	testenv.MustHaveGoBuild(t)
-	dir, err := ioutil.TempDir("", "testpcalign")
+	dir, err := os.MkdirTemp("", "testpcalign")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -130,7 +129,7 @@ func TestPCALIGN(t *testing.T) {
 	}
 
 	for _, test := range testCases {
-		if err := ioutil.WriteFile(tmpfile, test.code, 0644); err != nil {
+		if err := os.WriteFile(tmpfile, test.code, 0644); err != nil {
 			t.Fatal(err)
 		}
 		cmd := exec.Command(testenv.GoToolPath(t), "tool", "asm", "-S", "-o", tmpout, tmpfile)
diff --git a/src/cmd/internal/obj/objfile_test.go b/src/cmd/internal/obj/objfile_test.go
index 91e96e435d..79204c1858 100644
--- a/src/cmd/internal/obj/objfile_test.go
+++ b/src/cmd/internal/obj/objfile_test.go
@@ -6,15 +6,15 @@ package obj
 
 import (
 	"bytes"
-	"cmd/internal/goobj"
-	"cmd/internal/sys"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"testing"
 	"unsafe"
+
+	"cmd/internal/goobj"
+	"cmd/internal/sys"
 )
 
 var dummyArch = LinkArch{Arch: sys.ArchAMD64}
@@ -99,14 +99,14 @@ func TestSymbolTooLarge(t *testing.T) { // Issue 42054
 		t.Skip("skip on 32-bit architectures")
 	}
 
-	tmpdir, err := ioutil.TempDir("", "TestSymbolTooLarge")
+	tmpdir, err := os.MkdirTemp("", "TestSymbolTooLarge")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer os.RemoveAll(tmpdir)
 
 	src := filepath.Join(tmpdir, "p.go")
-	err = ioutil.WriteFile(src, []byte("package p; var x [1<<32]byte"), 0666)
+	err = os.WriteFile(src, []byte("package p; var x [1<<32]byte"), 0666)
 	if err != nil {
 		t.Fatalf("failed to write source file: %v\n", err)
 	}
@@ -129,7 +129,7 @@ func TestNoRefName(t *testing.T) {
 	tmpdir := t.TempDir()
 
 	src := filepath.Join(tmpdir, "x.go")
-	err := ioutil.WriteFile(src, []byte("package main; import \"fmt\"; func main() { fmt.Println(123) }\n"), 0666)
+	err := os.WriteFile(src, []byte("package main; import \"fmt\"; func main() { fmt.Println(123) }\n"), 0666)
 	if err != nil {
 		t.Fatalf("failed to write source file: %v\n", err)
 	}
diff --git a/src/cmd/internal/obj/ppc64/asm_test.go b/src/cmd/internal/obj/ppc64/asm_test.go
index c96f991293..aef442e485 100644
--- a/src/cmd/internal/obj/ppc64/asm_test.go
+++ b/src/cmd/internal/obj/ppc64/asm_test.go
@@ -6,11 +6,8 @@ package ppc64
 
 import (
 	"bytes"
-	"cmd/internal/obj"
-	"cmd/internal/objabi"
 	"fmt"
 	"internal/testenv"
-	"io/ioutil"
 	"math"
 	"os"
 	"os/exec"
@@ -18,6 +15,9 @@ import (
 	"regexp"
 	"strings"
 	"testing"
+
+	"cmd/internal/obj"
+	"cmd/internal/objabi"
 )
 
 var platformEnvs = [][]string{
@@ -167,7 +167,7 @@ PNOP
 func TestPfxAlign(t *testing.T) {
 	testenv.MustHaveGoBuild(t)
 
-	dir, err := ioutil.TempDir("", "testpfxalign")
+	dir, err := os.MkdirTemp("", "testpfxalign")
 	if err != nil {
 		t.Fatalf("could not create directory: %v", err)
 	}
@@ -188,7 +188,7 @@ func TestPfxAlign(t *testing.T) {
 
 	for _, pgm := range pgms {
 		tmpfile := filepath.Join(dir, "x.s")
-		err = ioutil.WriteFile(tmpfile, pgm.text, 0644)
+		err = os.WriteFile(tmpfile, pgm.text, 0644)
 		if err != nil {
 			t.Fatalf("can't write output: %v\n", err)
 		}
@@ -217,7 +217,7 @@ func TestLarge(t *testing.T) {
 	}
 	testenv.MustHaveGoBuild(t)
 
-	dir, err := ioutil.TempDir("", "testlarge")
+	dir, err := os.MkdirTemp("", "testlarge")
 	if err != nil {
 		t.Fatalf("could not create directory: %v", err)
 	}
@@ -281,7 +281,7 @@ func TestLarge(t *testing.T) {
 		gen(buf, test.jmpinsn)
 
 		tmpfile := filepath.Join(dir, "x.s")
-		err = ioutil.WriteFile(tmpfile, buf.Bytes(), 0644)
+		err = os.WriteFile(tmpfile, buf.Bytes(), 0644)
 		if err != nil {
 			t.Fatalf("can't write output: %v\n", err)
 		}
@@ -336,7 +336,7 @@ func TestPCalign(t *testing.T) {
 
 	testenv.MustHaveGoBuild(t)
 
-	dir, err := ioutil.TempDir("", "testpcalign")
+	dir, err := os.MkdirTemp("", "testpcalign")
 	if err != nil {
 		t.Fatalf("could not create directory: %v", err)
 	}
@@ -345,7 +345,7 @@ func TestPCalign(t *testing.T) {
 	// generate a test with valid uses of PCALIGN
 
 	tmpfile := filepath.Join(dir, "x.s")
-	err = ioutil.WriteFile(tmpfile, []byte(validPCAlignSrc), 0644)
+	err = os.WriteFile(tmpfile, []byte(validPCAlignSrc), 0644)
 	if err != nil {
 		t.Fatalf("can't write output: %v\n", err)
 	}
@@ -385,7 +385,7 @@ func TestPCalign(t *testing.T) {
 	// generate a test with invalid use of PCALIGN
 
 	tmpfile = filepath.Join(dir, "xi.s")
-	err = ioutil.WriteFile(tmpfile, []byte(invalidPCAlignSrc), 0644)
+	err = os.WriteFile(tmpfile, []byte(invalidPCAlignSrc), 0644)
 	if err != nil {
 		t.Fatalf("can't write output: %v\n", err)
 	}
diff --git a/src/cmd/internal/obj/riscv/asm_test.go b/src/cmd/internal/obj/riscv/asm_test.go
index b23142dbe8..c798e98873 100644
--- a/src/cmd/internal/obj/riscv/asm_test.go
+++ b/src/cmd/internal/obj/riscv/asm_test.go
@@ -8,7 +8,6 @@ import (
 	"bytes"
 	"fmt"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -24,7 +23,7 @@ func TestLargeBranch(t *testing.T) {
 	}
 	testenv.MustHaveGoBuild(t)
 
-	dir, err := ioutil.TempDir("", "testlargebranch")
+	dir, err := os.MkdirTemp("", "testlargebranch")
 	if err != nil {
 		t.Fatalf("Could not create directory: %v", err)
 	}
@@ -35,7 +34,7 @@ func TestLargeBranch(t *testing.T) {
 	genLargeBranch(buf)
 
 	tmpfile := filepath.Join(dir, "x.s")
-	if err := ioutil.WriteFile(tmpfile, buf.Bytes(), 0644); err != nil {
+	if err := os.WriteFile(tmpfile, buf.Bytes(), 0644); err != nil {
 		t.Fatalf("Failed to write file: %v", err)
 	}
 
@@ -67,13 +66,13 @@ func TestLargeCall(t *testing.T) {
 	}
 	testenv.MustHaveGoBuild(t)
 
-	dir, err := ioutil.TempDir("", "testlargecall")
+	dir, err := os.MkdirTemp("", "testlargecall")
 	if err != nil {
 		t.Fatalf("could not create directory: %v", err)
 	}
 	defer os.RemoveAll(dir)
 
-	if err := ioutil.WriteFile(filepath.Join(dir, "go.mod"), []byte("module largecall"), 0644); err != nil {
+	if err := os.WriteFile(filepath.Join(dir, "go.mod"), []byte("module largecall"), 0644); err != nil {
 		t.Fatalf("Failed to write file: %v\n", err)
 	}
 	main := `package main
@@ -84,7 +83,7 @@ func main() {
 func x()
 func y()
 `
-	if err := ioutil.WriteFile(filepath.Join(dir, "x.go"), []byte(main), 0644); err != nil {
+	if err := os.WriteFile(filepath.Join(dir, "x.go"), []byte(main), 0644); err != nil {
 		t.Fatalf("failed to write main: %v\n", err)
 	}
 
@@ -92,7 +91,7 @@ func y()
 	buf := bytes.NewBuffer(make([]byte, 0, 7000000))
 	genLargeCall(buf)
 
-	if err := ioutil.WriteFile(filepath.Join(dir, "x.s"), buf.Bytes(), 0644); err != nil {
+	if err := os.WriteFile(filepath.Join(dir, "x.s"), buf.Bytes(), 0644); err != nil {
 		t.Fatalf("Failed to write file: %v\n", err)
 	}
 
@@ -130,13 +129,13 @@ func genLargeCall(buf *bytes.Buffer) {
 
 // Issue 20348.
 func TestNoRet(t *testing.T) {
-	dir, err := ioutil.TempDir("", "testnoret")
+	dir, err := os.MkdirTemp("", "testnoret")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer os.RemoveAll(dir)
 	tmpfile := filepath.Join(dir, "x.s")
-	if err := ioutil.WriteFile(tmpfile, []byte("TEXT ·stub(SB),$0-0\nNOP\n"), 0644); err != nil {
+	if err := os.WriteFile(tmpfile, []byte("TEXT ·stub(SB),$0-0\nNOP\n"), 0644); err != nil {
 		t.Fatal(err)
 	}
 	cmd := exec.Command(testenv.GoToolPath(t), "tool", "asm", "-o", filepath.Join(dir, "x.o"), tmpfile)
@@ -147,7 +146,7 @@ func TestNoRet(t *testing.T) {
 }
 
 func TestImmediateSplitting(t *testing.T) {
-	dir, err := ioutil.TempDir("", "testimmsplit")
+	dir, err := os.MkdirTemp("", "testimmsplit")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -190,7 +189,7 @@ TEXT _stub(SB),$0-0
 	MOVF	F6, 4096(X5)
 	MOVD	F6, 4096(X5)
 `
-	if err := ioutil.WriteFile(tmpfile, []byte(asm), 0644); err != nil {
+	if err := os.WriteFile(tmpfile, []byte(asm), 0644); err != nil {
 		t.Fatal(err)
 	}
 	cmd := exec.Command(testenv.GoToolPath(t), "tool", "asm", "-o", filepath.Join(dir, "x.o"), tmpfile)
diff --git a/src/cmd/internal/obj/x86/obj6_test.go b/src/cmd/internal/obj/x86/obj6_test.go
index f9dd584569..6384fa07d8 100644
--- a/src/cmd/internal/obj/x86/obj6_test.go
+++ b/src/cmd/internal/obj/x86/obj6_test.go
@@ -5,7 +5,6 @@ import (
 	"bytes"
 	"fmt"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -81,7 +80,7 @@ func normalize(s string) string {
 }
 
 func asmOutput(t *testing.T, s string) []byte {
-	tmpdir, err := ioutil.TempDir("", "progedittest")
+	tmpdir, err := os.MkdirTemp("", "progedittest")
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/src/cmd/internal/obj/x86/pcrelative_test.go b/src/cmd/internal/obj/x86/pcrelative_test.go
index 487a65d8dc..a600006634 100644
--- a/src/cmd/internal/obj/x86/pcrelative_test.go
+++ b/src/cmd/internal/obj/x86/pcrelative_test.go
@@ -8,7 +8,6 @@ import (
 	"bytes"
 	"fmt"
 	"internal/testenv"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -33,12 +32,12 @@ func main() {
 `
 
 func objdumpOutput(t *testing.T, mname, source string) []byte {
-	tmpdir, err := ioutil.TempDir("", mname)
+	tmpdir, err := os.MkdirTemp("", mname)
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer os.RemoveAll(tmpdir)
-	err = ioutil.WriteFile(filepath.Join(tmpdir, "go.mod"), []byte(fmt.Sprintf("module %s\n", mname)), 0666)
+	err = os.WriteFile(filepath.Join(tmpdir, "go.mod"), []byte(fmt.Sprintf("module %s\n", mname)), 0666)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/src/cmd/internal/objabi/flag.go b/src/cmd/internal/objabi/flag.go
index 747207965e..858976e645 100644
--- a/src/cmd/internal/objabi/flag.go
+++ b/src/cmd/internal/objabi/flag.go
@@ -9,7 +9,6 @@ import (
 	"fmt"
 	"internal/buildcfg"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 	"reflect"
@@ -57,7 +56,7 @@ func expandArgs(in []string) (out []string) {
 				out = make([]string, 0, len(in)*2)
 				out = append(out, in[:i]...)
 			}
-			slurp, err := ioutil.ReadFile(s[1:])
+			slurp, err := os.ReadFile(s[1:])
 			if err != nil {
 				log.Fatal(err)
 			}
diff --git a/src/cmd/internal/objfile/disasm.go b/src/cmd/internal/objfile/disasm.go
index b5f1cd1632..c298d7e1a9 100644
--- a/src/cmd/internal/objfile/disasm.go
+++ b/src/cmd/internal/objfile/disasm.go
@@ -7,13 +7,11 @@ package objfile
 import (
 	"bufio"
 	"bytes"
-	"cmd/internal/src"
 	"container/list"
 	"debug/gosym"
 	"encoding/binary"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -21,6 +19,8 @@ import (
 	"strings"
 	"text/tabwriter"
 
+	"cmd/internal/src"
+
 	"golang.org/x/arch/arm/armasm"
 	"golang.org/x/arch/arm64/arm64asm"
 	"golang.org/x/arch/ppc64/ppc64asm"
@@ -157,7 +157,7 @@ func (fc *FileCache) Line(filename string, line int) ([]byte, error) {
 	}
 
 	if e == nil {
-		content, err := ioutil.ReadFile(filename)
+		content, err := os.ReadFile(filename)
 		if err != nil {
 			return nil, err
 		}
diff --git a/src/cmd/internal/pkgpath/pkgpath.go b/src/cmd/internal/pkgpath/pkgpath.go
index e3c76dced4..0bec137a70 100644
--- a/src/cmd/internal/pkgpath/pkgpath.go
+++ b/src/cmd/internal/pkgpath/pkgpath.go
@@ -10,7 +10,6 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"strings"
@@ -19,7 +18,7 @@ import (
 // ToSymbolFunc returns a function that may be used to convert a
 // package path into a string suitable for use as a symbol.
 // cmd is the gccgo/GoLLVM compiler in use, and tmpdir is a temporary
-// directory to pass to ioutil.TempFile.
+// directory to pass to os.CreateTemp().
 // For example, this returns a function that converts "net/http"
 // into a string like "net..z2fhttp". The actual string varies for
 // different gccgo/GoLLVM versions, which is why this returns a function
@@ -32,7 +31,7 @@ func ToSymbolFunc(cmd, tmpdir string) (func(string) string, error) {
 	// the same string. More recent versions use a new mangler
 	// that avoids these collisions.
 	const filepat = "*_gccgo_manglechck.go"
-	f, err := ioutil.TempFile(tmpdir, filepat)
+	f, err := os.CreateTemp(tmpdir, filepat)
 	if err != nil {
 		return nil, err
 	}
@@ -40,7 +39,7 @@ func ToSymbolFunc(cmd, tmpdir string) (func(string) string, error) {
 	f.Close()
 	defer os.Remove(gofilename)
 
-	if err := ioutil.WriteFile(gofilename, []byte(mangleCheckCode), 0644); err != nil {
+	if err := os.WriteFile(gofilename, []byte(mangleCheckCode), 0644); err != nil {
 		return nil, err
 	}
 
diff --git a/src/cmd/internal/test2json/test2json_test.go b/src/cmd/internal/test2json/test2json_test.go
index e69739d3fe..dee3920511 100644
--- a/src/cmd/internal/test2json/test2json_test.go
+++ b/src/cmd/internal/test2json/test2json_test.go
@@ -10,7 +10,7 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"reflect"
 	"strings"
@@ -28,7 +28,7 @@ func TestGolden(t *testing.T) {
 	for _, file := range files {
 		name := strings.TrimSuffix(filepath.Base(file), ".test")
 		t.Run(name, func(t *testing.T) {
-			orig, err := ioutil.ReadFile(file)
+			orig, err := os.ReadFile(file)
 			if err != nil {
 				t.Fatal(err)
 			}
@@ -46,13 +46,13 @@ func TestGolden(t *testing.T) {
 			if *update {
 				js := strings.TrimSuffix(file, ".test") + ".json"
 				t.Logf("rewriting %s", js)
-				if err := ioutil.WriteFile(js, buf.Bytes(), 0666); err != nil {
+				if err := os.WriteFile(js, buf.Bytes(), 0666); err != nil {
 					t.Fatal(err)
 				}
 				return
 			}
 
-			want, err := ioutil.ReadFile(strings.TrimSuffix(file, ".test") + ".json")
+			want, err := os.ReadFile(strings.TrimSuffix(file, ".test") + ".json")
 			if err != nil {
 				t.Fatal(err)
 			}