bufio: realign struct Reader

This reduce the Reader allocation size from 72 to 40 bytes and
Writer allocation size from 64 to 40 bytes.

1 files changed, 5 insertions, 4 deletions

diff --git a/src/bufio/bufio.go b/src/bufio/bufio.go
index f9b762be8d..79e7f3cf57 100644
--- a/src/bufio/bufio.go
+++ b/src/bufio/bufio.go
@@ -33,10 +33,10 @@ var (
 // alternatively the zero value of a Reader may be used after calling [Reader.Reset]
 // on it.
 type Reader struct {
-	buf          []byte
 	rd           io.Reader // reader provided by the client
-	r, w         int       // buf read and write positions
 	err          error
+	buf          []byte
+	r, w         int // buf read and write positions
 	lastByte     int // last byte read for UnreadByte; -1 means invalid
 	lastRuneSize int // size of last rune read for UnreadRune; -1 means invalid
 }
@@ -577,10 +577,10 @@ func (b *Reader) writeBuf(w io.Writer) (int64, error) {
 // [Writer.Flush] method to guarantee all data has been forwarded to
 // the underlying [io.Writer].
 type Writer struct {
+	wr  io.Writer
 	err error
 	buf []byte
 	n   int
-	wr  io.Writer
 }
 
 // NewWriterSize returns a new [Writer] whose buffer has at least the specified
@@ -794,7 +794,8 @@ func (b *Writer) ReadFrom(r io.Reader) (n int64, err error) {
 			}
 		}
 		if readerFromOK && b.Buffered() == 0 {
-			nn, err := readerFrom.ReadFrom(r)
+			var nn int64
+			nn, err = readerFrom.ReadFrom(r)
 			b.err = err
 			n += nn
 			return n, err