libgo: update to Go1.16beta1 release

This does not yet include support for the //go:embed directive added
in this release.

	* Makefile.am (check-runtime): Don't create check-runtime-dir.
	(mostlyclean-local): Don't remove check-runtime-dir.
	(check-go-tool, check-vet): Copy in go.mod and modules.txt.
	(check-cgo-test, check-carchive-test): Add go.mod file.
	* Makefile.in: Regenerate.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/280172

2 files changed, 11 insertions, 12 deletions

diff --git a/libgo/go/bufio/bufio.go b/libgo/go/bufio/bufio.go
index 7cbd542..6baf9b9 100644
--- a/libgo/go/bufio/bufio.go
+++ b/libgo/go/bufio/bufio.go
@@ -425,7 +425,7 @@ func (b *Reader) ReadLine() (line []byte, isPrefix bool, err error) {
 // of bytes in the combined first two elements, error).
 // The complete result is equal to
 // `bytes.Join(append(fullBuffers, finalFragment), nil)`, which has a
-// length of `totalLen`. The result is strucured in this way to allow callers
+// length of `totalLen`. The result is structured in this way to allow callers
 // to minimize allocations and copies.
 func (b *Reader) collectFragments(delim byte) (fullBuffers [][]byte, finalFragment []byte, totalLen int, err error) {
 	var frag []byte
diff --git a/libgo/go/bufio/bufio_test.go b/libgo/go/bufio/bufio_test.go
index cb68f3b..d7b34bd 100644
--- a/libgo/go/bufio/bufio_test.go
+++ b/libgo/go/bufio/bufio_test.go
@@ -10,7 +10,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"strings"
 	"testing"
 	"testing/iotest"
@@ -147,7 +146,7 @@ func TestReader(t *testing.T) {
 	for i := 0; i < len(texts)-1; i++ {
 		texts[i] = str + "\n"
 		all += texts[i]
-		str += string(rune(i)%26 + 'a')
+		str += string(rune(i%26 + 'a'))
 	}
 	texts[len(texts)-1] = all
 
@@ -886,7 +885,7 @@ func TestReadEmptyBuffer(t *testing.T) {
 
 func TestLinesAfterRead(t *testing.T) {
 	l := NewReaderSize(bytes.NewReader([]byte("foo")), minReadBufferSize)
-	_, err := ioutil.ReadAll(l)
+	_, err := io.ReadAll(l)
 	if err != nil {
 		t.Error(err)
 		return
@@ -1130,7 +1129,7 @@ func TestWriterReadFromCounts(t *testing.T) {
 	}
 }
 
-// A writeCountingDiscard is like ioutil.Discard and counts the number of times
+// A writeCountingDiscard is like io.Discard and counts the number of times
 // Write is called on it.
 type writeCountingDiscard int
 
@@ -1300,7 +1299,7 @@ func TestReaderReset(t *testing.T) {
 		t.Errorf("buf = %q; want foo", buf)
 	}
 	r.Reset(strings.NewReader("bar bar"))
-	all, err := ioutil.ReadAll(r)
+	all, err := io.ReadAll(r)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -1645,13 +1644,13 @@ func BenchmarkReaderWriteToOptimal(b *testing.B) {
 	buf := make([]byte, bufSize)
 	r := bytes.NewReader(buf)
 	srcReader := NewReaderSize(onlyReader{r}, 1<<10)
-	if _, ok := ioutil.Discard.(io.ReaderFrom); !ok {
-		b.Fatal("ioutil.Discard doesn't support ReaderFrom")
+	if _, ok := io.Discard.(io.ReaderFrom); !ok {
+		b.Fatal("io.Discard doesn't support ReaderFrom")
 	}
 	for i := 0; i < b.N; i++ {
 		r.Seek(0, io.SeekStart)
 		srcReader.Reset(onlyReader{r})
-		n, err := srcReader.WriteTo(ioutil.Discard)
+		n, err := srcReader.WriteTo(io.Discard)
 		if err != nil {
 			b.Fatal(err)
 		}
@@ -1722,7 +1721,7 @@ func BenchmarkReaderEmpty(b *testing.B) {
 	str := strings.Repeat("x", 16<<10)
 	for i := 0; i < b.N; i++ {
 		br := NewReader(strings.NewReader(str))
-		n, err := io.Copy(ioutil.Discard, br)
+		n, err := io.Copy(io.Discard, br)
 		if err != nil {
 			b.Fatal(err)
 		}
@@ -1737,7 +1736,7 @@ func BenchmarkWriterEmpty(b *testing.B) {
 	str := strings.Repeat("x", 1<<10)
 	bs := []byte(str)
 	for i := 0; i < b.N; i++ {
-		bw := NewWriter(ioutil.Discard)
+		bw := NewWriter(io.Discard)
 		bw.Flush()
 		bw.WriteByte('a')
 		bw.Flush()
@@ -1752,7 +1751,7 @@ func BenchmarkWriterEmpty(b *testing.B) {
 
 func BenchmarkWriterFlush(b *testing.B) {
 	b.ReportAllocs()
-	bw := NewWriter(ioutil.Discard)
+	bw := NewWriter(io.Discard)
 	str := strings.Repeat("x", 50)
 	for i := 0; i < b.N; i++ {
 		bw.WriteString(str)