libgo: update to Go 1.8 release candidate 1

Compiler changes:
      * Change map assignment to use mapassign and assign value directly.
      * Change string iteration to use decoderune, faster for ASCII strings.
      * Change makeslice to take int, and use makeslice64 for larger values.
      * Add new noverflow field to hmap struct used for maps.
    
    Unresolved problems, to be fixed later:
      * Commented out test in go/types/sizes_test.go that doesn't compile.
      * Commented out reflect.TestStructOf test for padding after zero-sized field.
    
    Reviewed-on: https://go-review.googlesource.com/35231

gotools/:
	Updates for Go 1.8rc1.
	* Makefile.am (go_cmd_go_files): Add bug.go.
	(s-zdefaultcc): Write defaultPkgConfig.
	* Makefile.in: Rebuild.

From-SVN: r244456

libgo/go/encoding/binary/binary.go

@@ -7,7 +7,7 @@
 //
 // Numbers are translated by reading and writing fixed-size values.
 // A fixed-size value is either a fixed-size arithmetic
-// type (int8, uint8, int16, float32, complex64, ...)
+// type (bool, int8, uint8, int16, float32, complex64, ...)
 // or an array or struct containing only fixed-size values.
 //
 // The varint functions encode and decode single integer values using
@@ -147,6 +147,8 @@ func (bigEndian) GoString() string { return "binary.BigEndian" }
 // of fixed-size values.
 // Bytes read from r are decoded using the specified byte order
 // and written to successive fields of the data.
+// When decoding boolean values, a zero byte is decoded as false, and
+// any other non-zero byte is decoded as true.
 // When reading into structs, the field data for fields with
 // blank (_) field names is skipped; i.e., blank field names
 // may be used for padding.
@@ -169,6 +171,8 @@ func Read(r io.Reader, order ByteOrder, data interface{}) error {
 			return err
 		}
 		switch data := data.(type) {
+		case *bool:
+			*data = b[0] != 0
 		case *int8:
 			*data = int8(b[0])
 		case *uint8:
@@ -185,8 +189,12 @@ func Read(r io.Reader, order ByteOrder, data interface{}) error {
 			*data = int64(order.Uint64(bs))
 		case *uint64:
 			*data = order.Uint64(bs)
-		case []int8:
+		case []bool:
 			for i, x := range bs { // Easier to loop over the input for 8-bit values.
+				data[i] = x != 0
+			}
+		case []int8:
+			for i, x := range bs {
 				data[i] = int8(x)
 			}
 		case []uint8:
@@ -243,6 +251,7 @@ func Read(r io.Reader, order ByteOrder, data interface{}) error {
 // Write writes the binary representation of data into w.
 // Data must be a fixed-size value or a slice of fixed-size
 // values, or a pointer to such data.
+// Boolean values encode as one byte: 1 for true, and 0 for false.
 // Bytes written to w are encoded using the specified byte order
 // and read from successive fields of the data.
 // When writing structs, zero values are written for fields
@@ -258,6 +267,26 @@ func Write(w io.Writer, order ByteOrder, data interface{}) error {
 			bs = b[:n]
 		}
 		switch v := data.(type) {
+		case *bool:
+			if *v {
+				b[0] = 1
+			} else {
+				b[0] = 0
+			}
+		case bool:
+			if v {
+				b[0] = 1
+			} else {
+				b[0] = 0
+			}
+		case []bool:
+			for i, x := range v {
+				if x {
+					bs[i] = 1
+				} else {
+					bs[i] = 0
+				}
+			}
 		case *int8:
 			b[0] = byte(*v)
 		case int8:
@@ -378,7 +407,8 @@ func sizeof(t reflect.Type) int {
 		}
 		return sum
 
-	case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
+	case reflect.Bool,
+		reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
 		reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
 		reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
 		return int(t.Size())
@@ -395,6 +425,21 @@ type coder struct {
 type decoder coder
 type encoder coder
 
+func (d *decoder) bool() bool {
+	x := d.buf[0]
+	d.buf = d.buf[1:]
+	return x != 0
+}
+
+func (e *encoder) bool(x bool) {
+	if x {
+		e.buf[0] = 1
+	} else {
+		e.buf[0] = 0
+	}
+	e.buf = e.buf[1:]
+}
+
 func (d *decoder) uint8() uint8 {
 	x := d.buf[0]
 	d.buf = d.buf[1:]
@@ -485,6 +530,9 @@ func (d *decoder) value(v reflect.Value) {
 			d.value(v.Index(i))
 		}
 
+	case reflect.Bool:
+		v.SetBool(d.bool())
+
 	case reflect.Int8:
 		v.SetInt(int64(d.int8()))
 	case reflect.Int16:
@@ -547,6 +595,9 @@ func (e *encoder) value(v reflect.Value) {
 			e.value(v.Index(i))
 		}
 
+	case reflect.Bool:
+		e.bool(v.Bool())
+
 	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
 		switch v.Type().Kind() {
 		case reflect.Int8:
@@ -609,7 +660,7 @@ func (e *encoder) skip(v reflect.Value) {
 // It returns zero if the type cannot be implemented by the fast path in Read or Write.
 func intDataSize(data interface{}) int {
 	switch data := data.(type) {
-	case int8, uint8, *int8, *uint8:
+	case bool, int8, uint8, *bool, *int8, *uint8:
 		return 1
 	case []int8:
 		return len(data)