}

	// Check that swig has a new enough version.
	// See https://golang.org/issue/22858.
	out, err := exec.Command(swig, "-version").CombinedOutput()
	if err != nil {
		t.Skipf("failed to get swig version:%s\n%s", err, string(out))
	}

	re := regexp.MustCompile(`[vV]ersion +(\d+)([.]\d+)?([.]\d+)?`)
	matches := re.FindSubmatch(out)
	if matches == nil {
		// Can't find version number; hope for the best.

	case *ast.CommClause:
		f.walk(n.Comm, ctxStmt, visit)
		f.walk(n.Body, ctxStmt, visit)
	case *ast.SelectStmt:
		f.walk(n.Body, ctxStmt, visit)
	case *ast.ForStmt:
		f.walk(n.Init, ctxStmt, visit)
		f.walk(&n.Cond, ctxExpr, visit)
		f.walk(n.Post, ctxStmt, visit)
		f.walk(n.Body, ctxStmt, visit)
	case *ast.RangeStmt:
		f.walk(&n.Key, ctxExpr, visit)
		f.walk(&n.Value, ctxExpr, visit)

	"go/ast"
	"go/token"
)

func (f *File) walkUnexpected(x interface{}, context astContext, visit func(*File, interface{}, astContext)) {
	switch n := x.(type) {
	default:
		error_(token.NoPos, "unexpected type %T in walk", x)
		panic("unexpected type")

	case *ast.IndexListExpr:
		f.walk(&n.X, ctxExpr, visit)
		f.walk(n.Indices, ctxExpr, visit)
	}
}

func funcTypeTypeParams(n *ast.FuncType) *ast.FieldList {
	return n.TypeParams

means that if a header file foo/bar.h exists both in the source
directory and also in the system include directory (or some other place
specified by a -I flag), then "#include <foo/bar.h>" will always find the
local version in preference to any other version.

The cgo tool is enabled by default for native builds on systems where
it is expected to work. It is disabled by default when cross-compiling

<!--{
	"Title": "The Go Programming Language Specification",
	"Subtitle": "Version of Oct 15, 2021",
	"Path": "/ref/spec"
}-->

<h2 id="Introduction">Introduction</h2>

<p>
This is the reference manual for the Go programming language as it was for
language version 1.17, in October 2021, before the introduction of generics.
It is provided for historical interest.
The current reference manual can be found <a href="/doc/go_spec.html">here</a>.

        If you have deleted your repo, please recreate it and publish a retraction.

        Retracting a module version involves adding a retract directive to your go.mod file and publishing a new version.
        For example: https://github.com/jba/retract-demo/blob/main/go.mod#L5-L8.
        See https://pkg.go.dev/about#removing-a-package for additional tips on retractions.
    validations:

	return &Tokenizer{
		s:    &s,
		base: src.NewFileBase(name, objabi.AbsFile(objabi.WorkingDir(), name, *flags.TrimPath)),
		line: 1,
		file: file,
	}
}

// We want center dot (·) and division slash (∕) to work as identifier characters.
func isIdentRune(ch rune, i int) bool {
	if unicode.IsLetter(ch) {
		return true
	}
	switch ch {
	case '_': // Underscore; traditional.
		return true

#cgo LDFLAGS: -framework CoreFoundation -framework Security
#include <TargetConditionals.h>
#include <CoreFoundation/CoreFoundation.h>
#include <Security/Security.h>
#if TARGET_OS_IPHONE == 0 && __MAC_OS_X_VERSION_MAX_ALLOWED < 101200
  typedef CFStringRef SecKeyAlgorithm;
  static CFDataRef SecKeyCreateSignature(SecKeyRef key, SecKeyAlgorithm algorithm, CFDataRef dataToSign, CFErrorRef *error){return NULL;}

	"strings"
	"time"
)

// BUG: Use of the Uid and Gid fields in Header could overflow on 32-bit
// architectures. If a large value is encountered when decoding, the result
// stored in Header will be the truncated version.

var tarinsecurepath = godebug.New("tarinsecurepath")

var (
	ErrHeader          = errors.New("archive/tar: invalid tar header")
	ErrWriteTooLong    = errors.New("archive/tar: write too long")

a "vendor/" prefix also maintains the invariant that standard
library packages begin with a dotless path element.

The module requirements of std and cmd do not influence version
selection in other modules. They are only considered when running
module commands like 'go get' and 'go mod vendor' from a directory
in GOROOT/src.

Maintaining vendor directories
==============================