/gc/scan/heap:bytes
		The total amount of heap space that is scannable.

	/gc/scan/stack:bytes
		The number of bytes of stack that were scanned last GC cycle.

	/gc/scan/total:bytes
		The total amount space that is scannable. Sum of all metrics in
		/gc/scan.

	/gc/stack/starting-size:bytes
		The stack size of new goroutines.

	/godebug/non-default-behavior/execerrdot:events

var errClosed = errors.New("i/o operation on closed connection")

// ServerConn is an artifact of Go's early HTTP implementation.
// It is low-level, old, and unused by Go's current HTTP stack.
// We should have deleted it before Go 1.
//
// Deprecated: Use the Server in package [net/http] instead.
type ServerConn struct {
	mu              sync.Mutex // read-write protects the following fields

	phaseName := "init"
	defer func() {
		if phaseName != "" {
			err := recover()
			stack := make([]byte, 16384)
			n := runtime.Stack(stack, false)
			stack = stack[:n]
			if f.HTMLWriter != nil {
				f.HTMLWriter.flushPhases()
			}
			f.Fatalf("panic during %s while compiling %s:\n\n%v\n\n%s\n", phaseName, f.Name, err, stack)
		}
	}()

	// Run all the passes
	if f.Log() {
		printFunc(f)
	}

		return "reflect: call of " + e.Method + " on zero Value"
	}
	return "reflect: call of " + e.Method + " on " + e.Kind.String() + " Value"
}

// methodName returns the name of the calling method,
// assumed to be two stack frames above.
func methodName() string {
	pc, _, _, _ := runtime.Caller(2)
	f := runtime.FuncForPC(pc)
	if f == nil {
		return "unknown method"
	}
	return f.Name()
}

}

func TestStackOverflow(t *testing.T) {
	output := runTestProg(t, "testprog", "StackOverflow")
	want := []string{
		"runtime: goroutine stack exceeds 1474560-byte limit\n",
		"fatal error: stack overflow",
		// information about the current SP and stack bounds
		"runtime: sp=",
		"stack=[",
	}
	if !strings.HasPrefix(output, want[0]) {
		t.Errorf("output does not start with %q", want[0])
	}
	for _, s := range want[1:] {

	REGCTXT = REG_R26 // environment for closures
	REGTMP  = REG_R27 // reserved for liblink
	REGG    = REG_R28 // G
	REGFP   = REG_R29 // frame pointer
	REGLINK = REG_R30

	// ARM64 uses R31 as both stack pointer and zero register,
	// depending on the instruction. To differentiate RSP from ZR,
	// we use a different numeric value for REGZERO and REGSP.
	REGZERO = REG_R31
	REGSP   = REG_RSP

	FREGRET = REG_F0

	{11, "SIGSEGV", "segmentation fault"},
	{12, "SIGUSR2", "user defined signal 2"},
	{13, "SIGPIPE", "broken pipe"},
	{14, "SIGALRM", "alarm clock"},
	{15, "SIGTERM", "terminated"},
	{16, "SIGSTKFLT", "stack fault"},
	{17, "SIGCHLD", "child exited"},
	{18, "SIGCONT", "continued"},
	{19, "SIGSTOP", "stopped (signal)"},
	{20, "SIGTSTP", "stopped"},
	{21, "SIGTTIN", "stopped (tty input)"},

func (p *Prog) InnermostFilename() string {
	// TODO For now, this is only used for debugging output, and if we need more/better information, it might change.
	// An example of what we might want to see is the full stack of positions for inlined code, so we get some visibility into what is recorded there.
	pos := p.Ctxt.InnermostPos(p.Pos)
	if !pos.IsKnown() {
		return "<unknown file name>"
	}
	return pos.Filename()
}

	// in particular, note that WebGL2's texImage2D takes up to 10 arguments
	const maxStackArgs = 16
	if size <= maxStackArgs {
		// as long as makeArgs is inlined, these will be stack-allocated
		argVals = make([]Value, size, maxStackArgs)
		argRefs = make([]ref, size, maxStackArgs)
	} else {
		// allocates on the heap, but exceeding maxStackArgs should be rare
		argVals = make([]Value, size)

f7 16 nosplit call f8
f8 16 nosplit call end
end 1000
REJECT

# Two paths both go over the stack limit.
start 0 call f1
f1 80 nosplit call f2 call f3
f2 40 nosplit call f4
f3 96 nosplit
f4 40 nosplit
REJECT

# Test cases near the 128-byte limit.

# Ordinary stack split frame is always okay.
start 112
start 116
start 120
start 124
start 128
start 132
start 136