Only valid on functions that declare a frame size of 0.
</li>
<li>
<code>TOPFRAME</code> = 2048
<br>
(For <code>TEXT</code> items.)
Function is the outermost frame of the call stack. Traceback should stop at this function.
</li>
</ul>

<h3 id="special-instructions">Special instructions</h3>

<p>

		// functions makeFuncStub and methodValueCall. The runtime expects
		// that it can find the first argument (ctxt) at 0(SP) in makeFuncStub
		// and methodValueCall's frame (see runtime/traceback.go:getArgInfo).
		// Normally callReflect and callMethod already do not modify the
		// argument, and keep it alive. But the compiler-generated ABI wrappers

	}
	print("\n")
	if refBase != 0 {
		print("runtime: found in object at *(", hex(refBase), "+", hex(refOff), ")\n")
		gcDumpObject("object", refBase, refOff)
	}
	getg().m.traceback = 2
	throw("found bad pointer in Go heap (incorrect use of unsafe or cgo?)")
}

// findObject returns the base address for the heap object containing

	// GOTRACEBACK envvar to stdout, and prints "hello" to stderr. We then chown
	// the program to "nobody" and set u+s on it. We execute the program, only
	// passing it two files, for stdin and stdout, and passing
	// GOTRACEBACK=system in the env.
	//
	// We expect that the program will trigger the SUID protections, resetting
	// the value of GOTRACEBACK, and opening the missing stderr descriptor, such

	// environment variable values (currently we only force GOTRACEBACK=none)
	//
	// Other packages may also disable specific functionality when secure mode
	// is enabled (determined by using linkname to call isSecureMode).

	secureEnv()
}

func secureEnv() {
	var hasTraceback bool
	for i := 0; i < len(envs); i++ {
		if stringslite.HasPrefix(envs[i], "GOTRACEBACK=") {
			hasTraceback = true
			envs[i] = "GOTRACEBACK=none"

package main

import (
	"fmt"
	"log"
	"os"
)

func main() {
	if os.Geteuid() == os.Getuid() {
		os.Exit(99)
	}

	fmt.Fprintf(os.Stdout, "GOTRACEBACK=%s\n", os.Getenv("GOTRACEBACK"))
	f, err := os.OpenFile(os.Getenv("TEST_OUTPUT"), os.O_CREATE|os.O_RDWR, 0600)
	if err != nil {
		log.Fatalf("os.Open failed: %s", err)
	}
	defer f.Close()
	fmt.Fprintf(os.Stderr, "hello\n")

		// from breaking tests that are trying to parse other command output.
		if strings.HasPrefix(env, "GODEBUG=") {
			continue
		}
		// Exclude GOTRACEBACK for the same reason.
		if strings.HasPrefix(env, "GOTRACEBACK=") {
			continue
		}
		cmd.Env = append(cmd.Env, env)
	}
	return cmd
}

// CommandContext is like exec.CommandContext, but:

	// Put this data in a read-only section.
	RODATA = 8

	// This data contains no pointers.
	NOPTR = 16

	// This is a wrapper function and should not count as
	// disabling 'recover' or appear in tracebacks by default.
	WRAPPER = 32

	// This function uses its incoming context register.
	NEEDCTXT = 64

	// When passed to objw.Global, causes Local to be set to true on the LSym it creates.
	LOCAL = 128

var flagQuick = flag.Bool("quick", false, "skip slow tests, for cmd/dist test runtime:cpu124")

func init() {
	// We're testing the runtime, so make tracebacks show things
	// in the runtime. This only raises the level, so it won't
	// override GOTRACEBACK=crash from the user.
	SetTracebackEnv("system")
}

var errf error

func errfn() error {
	return errf
}

func errfn1() error {
	return io.EOF
}

	if err := o.Close(); err != nil {
		t.Fatal(err)
	}

	env := []string{"TEST_OUTPUT=" + outputPath}
	for _, e := range os.Environ() {
		if strings.HasPrefix(e, "GODEBUG=") || strings.HasPrefix(e, "GOTRACEBACK=") {
			continue
		}
		env = append(env, e)
	}

	proc, err := os.StartProcess(fdsBin, []string{fdsBin}, &os.ProcAttr{
		Env:   env,
		Files: []*os.File{},
	})
	if err != nil {
		t.Fatal(err)
	}