_, err := w.ImportFrom("p", "", 0)
		if _, nogo := err.(*build.NoGoError); !nogo {
			t.Errorf("expected *build.NoGoError, got %T", err)
		}
	}
}

func TestIssue41358(t *testing.T) {
	if *flagCheck {
		// slow, not worth repeating in -check
		t.Skip("skipping with -check set")
	}
	testenv.MustHaveGoBuild(t)
	context := new(build.Context)
	*context = build.Default

make.bat goto ok
L10:echo all.bat must be run from go\src
L11::: cannot exit: would kill parent command interpreter
L12:goto end
L13::ok
L14:
L15:call .\make.bat --no-banner --no-local
L16:if %GOBUILDFAIL%==1 goto end
L17:call .\run.bat --no-rebuild --no-local
L18:if %GOBUILDFAIL%==1 goto end
L19:"%GOTOOLDIR%/dist" banner
L20:
L21::end
L22:if x%GOBUILDEXIT%==x1 exit %GOBUILDFAIL%
...

the use of cgo, and to 0 to disable it. The go tool will set the
build constraint "cgo" if cgo is enabled. The special import "C"
implies the "cgo" build constraint, as though the file also said
"//go:build cgo".  Therefore, if cgo is disabled, files that import
"C" will not be built by the go tool. (For more about build constraints
see https://golang.org/pkg/go/build/#hdr-Build_Constraints).

# That tree can be copied to a machine of the given target type
# and used as $GOROOT_BOOTSTRAP to bootstrap a local build.
#
# Only changes that have been committed to Git (at least locally,
# not necessary reviewed and submitted to master) are included in the tree.
#
# See also golang.org/x/build/cmd/genbootstrap, which is used
# to generate bootstrap tgz files for builders.

set -e

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build darwin

package issue24161arg

/*
#cgo LDFLAGS: -framework CoreFoundation
#include <CoreFoundation/CoreFoundation.h>
*/
import "C"

func test24161array() C.CFArrayRef {
	return C.CFArrayCreate(0, nil, 0, nil)

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build cgo

// Issue 26743: typedef of uint leads to inconsistent typedefs error.
// No runtime test; just make sure it compiles.

package cgotest

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build darwin

package issue24161arg

/*
#cgo LDFLAGS: -framework CoreFoundation
#include <CoreFoundation/CoreFoundation.h>
*/
import "C"
import "testing"

func Test(t *testing.T) {
	a := test24161array()
	C.CFArrayCreateCopy(0, a)

// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build aix || linux || dragonfly || openbsd || solaris

package tar

import (
	"syscall"
	"time"
)

func statAtime(st *syscall.Stat_t) time.Time {
	return time.Unix(st.Atim.Unix())
}

func statCtime(st *syscall.Stat_t) time.Time {
	return time.Unix(st.Ctim.Unix())

// Copyright 2021 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build !compiler_bootstrap

package main

import (
	"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)

// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build gc

#include "_cgo_export.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

/* Test calling panic from C.  This is what SWIG does.  */

extern void crosscall2(void (*fn)(void *, int), void *, int);
extern void _cgo_panic(void *, int);