fmt.Printf("%s\n", clone)
	clone[0] = 'd'
	fmt.Printf("%s\n", b)
	fmt.Printf("%s\n", clone)
	// Output:
	// abc
	// abc
	// dbc
}

func ExampleCompare() {
	// Interpret Compare's result by comparing it to zero.
	var a, b []byte
	if bytes.Compare(a, b) < 0 {
		// a less b
	}
	if bytes.Compare(a, b) <= 0 {
		// a less or equal b
	}
	if bytes.Compare(a, b) > 0 {
		// a greater b
	}

	"strconv"
	"strings"
	"testing"

	"cmd/asm/internal/lex"
	"cmd/internal/obj"
)

// An end-to-end test for the assembler: Do we print what we parse?
// Output is generated by, in effect, turning on -S and comparing the
// result against a golden file.

func testEndToEnd(t *testing.T, goarch, file string) {
	input := filepath.Join("testdata", file+".s")
	architecture, ctxt := setArch(goarch)
	architecture.Init(ctxt)

// A nil argument is equivalent to an empty slice.
func Equal(a, b []byte) bool {
	// Neither cmd/compile nor gccgo allocates for these string conversions.
	return string(a) == string(b)
}

// Compare returns an integer comparing two byte slices lexicographically.
// The result will be 0 if a == b, -1 if a < b, and +1 if a > b.
// A nil argument is equivalent to an empty slice.
func Compare(a, b []byte) int {
	return bytealg.Compare(a, b)
}

package tar

import "strings"

// Format represents the tar archive format.
//
// The original tar format was introduced in Unix V7.
// Since then, there have been multiple competing formats attempting to
// standardize or extend the V7 format to overcome its limitations.
// The most common formats are the USTAR, PAX, and GNU formats,
// each with their own advantages and limitations.
//

	// IDs above that range are defined by third-party vendors.
	// Since ZIP lacked high precision timestamps (nor an official specification
	// of the timezone used for the date fields), many competing extra fields
	// have been invented. Pervasive use effectively makes them "official".
	//
	// See http://mdfs.net/Docs/Comp/Archiving/Zip/ExtraField
	zip64ExtraID       = 0x0001 // Zip64 extended information

	if tok == '>' {
		isStatic = true
	} else if tok == scanner.Ident {
		abistr := p.get(scanner.Ident).String()
		if !p.allowABI {
			if issueError {
				p.errorf("ABI selector only permitted when compiling runtime, reference was to %q", name)
			}
		} else {
			theabi, valid := obj.ParseABI(abistr)
			if !valid {
				if issueError {
					p.errorf("malformed ABI selector %q in reference to %q",

		{"TEXT", "$:0:(SB, 0, $1", "expected '(', found 0"},          // Issue 12468.
		{"TEXT", "@B(SB),0,$0", "expected '(', found B"},             // Issue 23580.
		{"TEXT", "foo<ABIInternal>(SB),0", "ABI selector only permitted when compiling runtime, reference was to \"foo\""},
		{"FUNCDATA", "", "expect two operands for FUNCDATA"},
		{"FUNCDATA", "(SB ", "expect two operands for FUNCDATA"},
		{"DATA", "", "expect two operands for DATA"},

as C.stdout, or functions such as C.putchar.

If the import of "C" is immediately preceded by a comment, that
comment, called the preamble, is used as a header when compiling
the C parts of the package. For example:

	// #include <stdio.h>
	// #include <errno.h>
	import "C"

The preamble may contain any C code, including function and variable

	{"[X0,X3]", "register list: expected '-' after `[X0`, found ','"},
	{"[X0,X1,X2,X3]", "register list: expected '-' after `[X0`, found ','"},
	{"$foo<ABI0>", "ABI selector only permitted when compiling runtime, reference was to \"foo\""},
}

var amd64BadOperandRuntimeTests = []badOperandTest{
	{"$foo<bletch>", "malformed ABI selector \"bletch\" in reference to \"foo\""},
}

	TypeXHeader = 'x'

	// Type 'g' is used by the PAX format to store key-value records that
	// are relevant to all subsequent files.
	// This package only supports parsing and composing such headers,
	// but does not currently support persisting the global state across files.
	TypeXGlobalHeader = 'g'

	// Type 'S' indicates a sparse file in the GNU format.
	TypeGNUSparse = 'S'