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).

		_, 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

// Copyright 2016 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 && !windows

// Issue 18146: pthread_create failure during syscall.Exec.

package cgotest

import (
	"bytes"
	"crypto/md5"
	"os"
	"os/exec"
	"runtime"
	"syscall"
	"testing"
	"time"
)

func test18146(t *testing.T) {
	if testing.Short() {

		result *= 7
	}()
	return 6
}
</pre>

<h2 id="Built-in_functions">Built-in functions</h2>

<p>
Built-in functions are
<a href="#Predeclared_identifiers">predeclared</a>.
They are called like any other function but some of them
accept a type instead of an expression as the first argument.
</p>

<p>
The built-in functions do not have standard Go types,

			b = strconv.AppendInt(b, int64(i), 10)
			got.Write(b)
		}
	})
	if n > 0 {
		t.Errorf("allocations occurred while appending")
	}
}

func TestRuneIO(t *testing.T) {
	const NRune = 1000
	// Built a test slice while we write the data
	b := make([]byte, utf8.UTFMax*NRune)
	var buf Buffer
	n := 0
	for r := rune(0); r < NRune; r++ {
		size := utf8.EncodeRune(b[n:], r)
		nbytes, err := buf.WriteRune(r)

# license that can be found in the LICENSE file.

set -e
if [ ! -f make.bash ]; then
	echo 'all.bash must be run from $GOROOT/src' 1>&2
	exit 1
fi
. ./make.bash "$@" --no-banner
bash run.bash --no-rebuild

# in the CL match the update.bash in the CL.

# Versions to use.
CODE=2024a
DATA=2024a

set -e

cd $(dirname $0)
rm -rf work
mkdir work
go build -o work/mkzip mkzip.go # build now for correct paths in build errors
cd work
mkdir zoneinfo
curl -sS -L -O https://www.iana.org/time-zones/repository/releases/tzcode$CODE.tar.gz

// Copyright 2019 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 linux && cgo

package cgotest

import (
	"fmt"
	"internal/testenv"
	"os"
	"runtime"
	"sort"
	"strings"
	"syscall"
	"testing"
)

// #include <stdio.h>
// #include <stdlib.h>
// #include <pthread.h>
// #include <unistd.h>

// Copyright 2017 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 linux

package bytes_test

import (
	. "bytes"
	"syscall"
	"testing"
)

// This file tests the situation where byte operations are checking
// data very near to a page boundary. We want to make sure those
// operations do not read across the boundary and cause a page

// The common methods [Store] and [Deflate] are built in.
func RegisterDecompressor(method uint16, dcomp Decompressor) {
	if _, dup := decompressors.LoadOrStore(method, dcomp); dup {
		panic("decompressor already registered")
	}
}

// RegisterCompressor registers custom compressors for a specified method ID.
// The common methods [Store] and [Deflate] are built in.
func RegisterCompressor(method uint16, comp Compressor) {