// mmap calls the mmap system call. It is implemented in assembly.
// We only pass the lower 32 bits of file offset to the
// assembly routine; the higher bits (if required), should be provided
// by the assembly routine as 0.
// The err result is an OS error code such as ENOMEM.
func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (p unsafe.Pointer, err int)

stderr '^flag provided but not defined: -unknownflag'

! go run -unknownflag oops rsc.io/fortune/nonexist@v0.0.1
! stderr switching
stderr '^flag provided but not defined: -unknownflag'

# go run can handle unknown flag with argument.
! go run -unknown=flag rsc.io/fortune/nonexist@v0.0.1
stderr '^go: rsc.io/fortune@v0.0.1 requires go >= 1.21rc999; switching to go1.22.9$'
stderr '^flag provided but not defined: -unknown'

package tar

import (
	"errors"
	"fmt"
	"io"
	"io/fs"
	"path"
	"slices"
	"strings"
	"time"
)

// Writer provides sequential writing of a tar archive.
// [Writer.WriteHeader] begins a new file with the provided [Header],
// and then Writer can be treated as an io.Writer to supply that file's data.
type Writer struct {
	w    io.Writer

// Copyright 2020 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.

// Package traceviewer provides definitions of the JSON data structures
// used by the Chrome trace viewer.
//
// The official description of the format is in this file:
// https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU/preview
//

// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
//
// Developed at SunPro, a Sun Microsystems, Inc. business.
// Permission to use, copy, modify, and distribute this
// software is freely granted, provided that this notice
// is preserved.
// ====================================================
//
// expm1(x)
// Returns exp(x)-1, the exponential of x minus 1.
//
// Method
//   1. Argument reduction:

modification, are permitted provided that the following conditions are
met:

   * Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.

}

var ErrTooNew = errors.New("module too new")

func (e *TooNewError) Is(err error) bool {
	return err == ErrTooNew
}

// A Switcher provides the ability to switch to a new toolchain in response to TooNewErrors.
// See [cmd/go/internal/toolchain.Switcher] for documentation.
type Switcher interface {
	Error(err error)
	Switch(ctx context.Context)

// - RUnlock -> Lock:  writerSem
//
// The methods below temporarily disable handling of race synchronization
// events in order to provide the more precise model above to the race
// detector.
//
// For example, atomic.AddInt32 in RLock should not appear to provide
// acquire-release semantics, which would incorrectly synchronize racing
// readers, thus potentially missing races.

// RLock locks rw for reading.
//

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package race implements data race detection logic.
// No public interface is provided.
// For details about the race detector see
// https://golang.org/doc/articles/race_detector.html
package race

package startlinetest

// Defined in func_amd64.s, this is a trivial assembly function that calls
// runtime_test.callerStartLine.
func AsmFunc() int

// Provided by runtime_test.