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

package runtime

import _ "unsafe" // for go:linkname

//go:linkname setMaxStack runtime/debug.setMaxStack
func setMaxStack(in int) (out int) {
	out = int(maxstacksize)
	maxstacksize = uintptr(in)
	return out
}

//go:linkname setPanicOnFault runtime/debug.setPanicOnFault
func setPanicOnFault(new bool) (old bool) {

// license that can be found in the LICENSE file.

package debug

import (
	"time"
)

// Implemented in package runtime.
func readGCStats(*[]time.Duration)
func freeOSMemory()
func setMaxStack(int) int
func setGCPercent(int32) int32
func setPanicOnFault(bool) bool
func setMaxThreads(int) int

package main

import "runtime/debug"

type Foo struct {
	A [1 << 20]byte
	B string
}

func run(c chan bool) {
	f := new(Foo)
	*f = Foo{B: "hello"}
	c <- true
}

func main() {
	debug.SetMaxStack(1 << 16)
	c := make(chan bool)
	go run(c)
	<-c

		}
	}

	go F()
	go F()
	runtime.Goexit()
}

func StackOverflow() {
	var f func() byte
	f = func() byte {
		var buf [64 << 10]byte
		return buf[0] + f()
	}
	debug.SetMaxStack(1474560)
	f()
}

func ThreadExhaustion() {
	debug.SetMaxThreads(10)
	c := make(chan int)
	for i := 0; i < 100; i++ {
		go func() {
			runtime.LockOSThread()
			c <- 0
			select {}
		}()
		<-c