// pollDesc contains 2 binary semaphores, rg and wg, to park reader and writer
// goroutines respectively. The semaphore can be in the following states:
//
//	pdReady - io readiness notification is pending;
//	          a goroutine consumes the notification by changing the state to pdNil.
//	pdWait - a goroutine prepares to park on the semaphore, but not yet parked;
//	         the goroutine commits to park by changing the state to G pointer,

//
// goarm should be an internal detail,
// but widely used packages access it using linkname.
// Notable members of the hall of shame include:
//   - github.com/creativeprojects/go-selfupdate
//
// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname goarm
var (
	goarm       uint8
	goarmsoftfp uint8
)

		{"block", []string{"runtime.chanrecv1", "runtime/pprof.blockChanDeep"}},
		{"mutex", []string{"sync.(*Mutex).Unlock", "runtime/pprof.blockMutexDeep"}},
		{"goroutine", []string{"runtime.gopark", "runtime.chanrecv", "runtime.chanrecv1", "runtime/pprof.goroutineDeep"}},
	}

	for _, test := range tests {
		t.Run(test.profiler, func(t *testing.T) {
			var buf bytes.Buffer

// returned data before calling ReadTrace again.
// ReadTrace must be called from one goroutine at a time.
func ReadTrace() []byte {
top:
	var buf []byte
	var park bool
	systemstack(func() {
		buf, park = readTrace0()
	})
	if park {
		gopark(func(gp *g, _ unsafe.Pointer) bool {
			if !trace.reader.CompareAndSwapNoWB(nil, gp) {
				// We're racing with another reader.
				// Wake up and handle this case.

	// safe-point because we don't have precise pointer maps for
	// all frames.
	if gp.asyncSafePoint {
		return false
	}
	// We also can't *shrink* the stack in the window between the
	// goroutine calling gopark to park on a channel and
	// gp.activeStackChans being set.
	if gp.parkingOnChan.Load() {
		return false
	}
	// We also can't copy the stack while tracing is enabled, and

	if t == nil {
		t = new(timer)
		t.init(goroutineReady, gp)
		gp.timer = t
	}
	when := nanotime() + ns
	if when < 0 { // check for overflow.
		when = maxWhen
	}
	gp.sleepWhen = when
	gopark(resetForSleep, nil, waitReasonSleep, traceBlockSleep, 1)
}

// resetForSleep is called after the goroutine is parked for timeSleep.
// We can't call timer.reset in timeSleep itself because if this is a short

		}
	}
	if s.gomaxprocs == nil {
		s.gomaxprocs = func() int32 {
			return gomaxprocs
		}
	}
}

// park parks the scavenger goroutine.
func (s *scavengerState) park() {
	lock(&s.lock)
	if getg() != s.g {
		throw("tried to park scavenger from another goroutine")
	}
	s.parked = true
	goparkunlock(&s.lock, waitReasonGCScavengeWait, traceBlockSystemGoroutine, 2)
}

	CGO_LDFLAGS_DISALLOW
	CXX
	FC
	GCCGO
	GO111MODULE
	GO386
	GOAMD64
	GOARCH
	GOARM
	GOARM64
	GOBIN
	GOCACHE
	GOCACHEPROG
	GOENV
	GOEXE
	GOEXPERIMENT
	GOFLAGS
	GOGCCFLAGS
	GOHOSTARCH
	GOHOSTOS
	GOINSECURE
	GOMIPS
	GOMIPS64
	GOMODCACHE
	GONOPROXY
	GONOSUMDB
	GOOS
	GOPATH
	GOPPC64
	GOPRIVATE
	GOPROXY
	GORISCV64
	GOROOT
	GOSUMDB
	GOTMPDIR
	GOTOOLCHAIN

go env GOWORK
stdout '^'$GOPATH'[\\/]src[\\/]go.work$'
go env
stdout '^(set )?GOWORK=''?'$GOPATH'[\\/]src[\\/]go.work''?$'

cd ..
go env GOWORK
! stdout .
go env
stdout 'GOWORK=("")?'

cd src
go env GOWORK
stdout 'go.work'

env GOWORK='off'
go env GOWORK
stdout 'off'

! go env -w GOWORK=off
stderr '^go: GOWORK cannot be modified$'

-- go.work --
go 1.18

use a
-- a/go.mod --

# go env GOMOD should not trigger a toolchain download
cd $GOPATH/mod
go env GOMOD
stdout mod[/\\]go.mod
! stderr 'go: toolchain go1.500 invoked to provide go1.700'

# go env GOWORK should not trigger a toolchain download
cd $GOPATH/work
go env GOWORK
stdout work[/\\]go.work
! stderr 'go: toolchain go1.500 invoked to provide go1.700'

-- $GOPATH/mod/go.mod --
module example.com

go 1.700