libgo: export NetBSD-specific types in mksysinfo.sh
[gcc.git] / libgo / go / runtime / crash_test.go
index 465b2d709644eed5c5143bcfbbc4ff416d145ece..aa97cf7d56822abe92917d63df69ed092d528f91 100644 (file)
 package runtime_test
 
 import (
+       "bytes"
+       "flag"
+       "fmt"
+       "internal/testenv"
        "io/ioutil"
        "os"
        "os/exec"
        "path/filepath"
+       "regexp"
        "runtime"
+       "strconv"
+       "strings"
+       "sync"
        "testing"
-       "text/template"
+       "time"
 )
 
-type crashTest struct {
-       Cgo bool
+var toRemove []string
+
+func TestMain(m *testing.M) {
+       status := m.Run()
+       for _, file := range toRemove {
+               os.RemoveAll(file)
+       }
+       os.Exit(status)
+}
+
+var testprog struct {
+       sync.Mutex
+       dir    string
+       target map[string]buildexe
 }
 
-// This test is a separate program, because it is testing
-// both main (m0) and non-main threads (m).
+type buildexe struct {
+       exe string
+       err error
+}
 
-func testCrashHandler(t *testing.T, ct *crashTest) {
-       if runtime.GOOS == "freebsd" || runtime.GOOS == "netbsd" {
-               // TODO(brainman): do not know why this test fails on freebsd
-               // TODO(jsing): figure out why this causes delayed failures
-               // on NetBSD - http://golang.org/issue/3954
-               t.Logf("skipping test on %q", runtime.GOOS)
-               return
+func runTestProg(t *testing.T, binary, name string, env ...string) string {
+       if *flagQuick {
+               t.Skip("-quick")
        }
 
-       st := template.Must(template.New("crashSource").Parse(crashSource))
+       testenv.MustHaveGoBuild(t)
 
-       dir, err := ioutil.TempDir("", "go-build")
+       exe, err := buildTestProg(t, binary)
        if err != nil {
-               t.Fatalf("failed to create temp directory: %v", err)
+               t.Fatal(err)
        }
-       defer os.RemoveAll(dir)
 
-       src := filepath.Join(dir, "main.go")
-       f, err := os.Create(src)
-       if err != nil {
-               t.Fatalf("failed to create %v: %v", src, err)
+       return runBuiltTestProg(t, exe, name, env...)
+}
+
+func runBuiltTestProg(t *testing.T, exe, name string, env ...string) string {
+       if *flagQuick {
+               t.Skip("-quick")
        }
-       err = st.Execute(f, ct)
-       if err != nil {
-               f.Close()
-               t.Fatalf("failed to execute template: %v", err)
+
+       testenv.MustHaveGoBuild(t)
+
+       cmd := testenv.CleanCmdEnv(exec.Command(exe, name))
+       cmd.Env = append(cmd.Env, env...)
+       if testing.Short() {
+               cmd.Env = append(cmd.Env, "RUNTIME_TEST_SHORT=1")
+       }
+       var b bytes.Buffer
+       cmd.Stdout = &b
+       cmd.Stderr = &b
+       if err := cmd.Start(); err != nil {
+               t.Fatalf("starting %s %s: %v", exe, name, err)
+       }
+
+       // If the process doesn't complete within 1 minute,
+       // assume it is hanging and kill it to get a stack trace.
+       p := cmd.Process
+       done := make(chan bool)
+       go func() {
+               scale := 1
+               // This GOARCH/GOOS test is copied from cmd/dist/test.go.
+               // TODO(iant): Have cmd/dist update the environment variable.
+               if runtime.GOARCH == "arm" || runtime.GOOS == "windows" {
+                       scale = 2
+               }
+               if s := os.Getenv("GO_TEST_TIMEOUT_SCALE"); s != "" {
+                       if sc, err := strconv.Atoi(s); err == nil {
+                               scale = sc
+                       }
+               }
+
+               select {
+               case <-done:
+               case <-time.After(time.Duration(scale) * time.Minute):
+                       p.Signal(sigquit)
+               }
+       }()
+
+       if err := cmd.Wait(); err != nil {
+               t.Logf("%s %s exit status: %v", exe, name, err)
+       }
+       close(done)
+
+       return b.String()
+}
+
+func buildTestProg(t *testing.T, binary string, flags ...string) (string, error) {
+       if *flagQuick {
+               t.Skip("-quick")
+       }
+
+       testprog.Lock()
+       defer testprog.Unlock()
+       if testprog.dir == "" {
+               dir, err := ioutil.TempDir("", "go-build")
+               if err != nil {
+                       t.Fatalf("failed to create temp directory: %v", err)
+               }
+               testprog.dir = dir
+               toRemove = append(toRemove, dir)
+       }
+
+       if testprog.target == nil {
+               testprog.target = make(map[string]buildexe)
+       }
+       name := binary
+       if len(flags) > 0 {
+               name += "_" + strings.Join(flags, "_")
+       }
+       target, ok := testprog.target[name]
+       if ok {
+               return target.exe, target.err
        }
-       f.Close()
 
-       got, err := exec.Command("go", "run", src).CombinedOutput()
+       exe := filepath.Join(testprog.dir, name+".exe")
+       cmd := exec.Command(testenv.GoToolPath(t), append([]string{"build", "-o", exe}, flags...)...)
+       cmd.Dir = "testdata/" + binary
+       out, err := testenv.CleanCmdEnv(cmd).CombinedOutput()
        if err != nil {
-               t.Fatalf("program exited with error: %v\n%v", err, string(got))
+               target.err = fmt.Errorf("building %s %v: %v\n%s", binary, flags, err, out)
+               testprog.target[name] = target
+               return "", target.err
+       }
+       target.exe = exe
+       testprog.target[name] = target
+       return exe, nil
+}
+
+func TestVDSO(t *testing.T) {
+       t.Parallel()
+       output := runTestProg(t, "testprog", "SignalInVDSO")
+       want := "success\n"
+       if output != want {
+               t.Fatalf("output:\n%s\n\nwanted:\n%s", output, want)
+       }
+}
+
+func testCrashHandler(t *testing.T, cgo bool) {
+       type crashTest struct {
+               Cgo bool
+       }
+       var output string
+       if cgo {
+               output = runTestProg(t, "testprogcgo", "Crash")
+       } else {
+               output = runTestProg(t, "testprog", "Crash")
        }
        want := "main: recovered done\nnew-thread: recovered done\nsecond-new-thread: recovered done\nmain-again: recovered done\n"
-       if string(got) != string(want) {
-               t.Fatalf("expected %q, but got %q", string(want), string(got))
+       if output != want {
+               t.Fatalf("output:\n%s\n\nwanted:\n%s", output, want)
        }
 }
 
 func TestCrashHandler(t *testing.T) {
-       testCrashHandler(t, &crashTest{Cgo: false})
+       testCrashHandler(t, false)
 }
 
-const crashSource = `
-package main
+func testDeadlock(t *testing.T, name string) {
+       output := runTestProg(t, "testprog", name)
+       want := "fatal error: all goroutines are asleep - deadlock!\n"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
 
-import (
-       "fmt"
-       "runtime"
-)
+func TestSimpleDeadlock(t *testing.T) {
+       testDeadlock(t, "SimpleDeadlock")
+}
 
-{{if .Cgo}}
-import "C"
-{{end}}
+func TestInitDeadlock(t *testing.T) {
+       testDeadlock(t, "InitDeadlock")
+}
 
-func test(name string) {
-       defer func() {
-               if x := recover(); x != nil {
-                       fmt.Printf(" recovered")
+func TestLockedDeadlock(t *testing.T) {
+       testDeadlock(t, "LockedDeadlock")
+}
+
+func TestLockedDeadlock2(t *testing.T) {
+       testDeadlock(t, "LockedDeadlock2")
+}
+
+func TestGoexitDeadlock(t *testing.T) {
+       output := runTestProg(t, "testprog", "GoexitDeadlock")
+       want := "no goroutines (main called runtime.Goexit) - deadlock!"
+       if !strings.Contains(output, want) {
+               t.Fatalf("output:\n%s\n\nwant output containing: %s", output, want)
+       }
+}
+
+func TestStackOverflow(t *testing.T) {
+       if runtime.Compiler == "gccgo" {
+               t.Skip("gccgo does not do stack overflow checking")
+       }
+       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:] {
+               if !strings.Contains(output, s) {
+                       t.Errorf("output does not contain %q", s)
                }
-               fmt.Printf(" done\n")
-       }()
-       fmt.Printf("%s:", name)
-       var s *string
-       _ = *s
-       fmt.Print("SHOULD NOT BE HERE")
+       }
+       if t.Failed() {
+               t.Logf("output:\n%s", output)
+       }
+}
+
+func TestThreadExhaustion(t *testing.T) {
+       output := runTestProg(t, "testprog", "ThreadExhaustion")
+       want := "runtime: program exceeds 10-thread limit\nfatal error: thread exhaustion"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+func TestRecursivePanic(t *testing.T) {
+       output := runTestProg(t, "testprog", "RecursivePanic")
+       want := `wrap: bad
+panic: again
+
+`
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+
+}
+
+func TestRecursivePanic2(t *testing.T) {
+       output := runTestProg(t, "testprog", "RecursivePanic2")
+       want := `first panic
+second panic
+panic: third panic
+
+`
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+
 }
 
-func testInNewThread(name string) {
-       c := make(chan bool)
+func TestRecursivePanic3(t *testing.T) {
+       output := runTestProg(t, "testprog", "RecursivePanic3")
+       want := `panic: first panic
+
+`
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+
+}
+
+func TestRecursivePanic4(t *testing.T) {
+       output := runTestProg(t, "testprog", "RecursivePanic4")
+       want := `panic: first panic [recovered]
+       panic: second panic
+`
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+
+}
+
+func TestGoexitCrash(t *testing.T) {
+       output := runTestProg(t, "testprog", "GoexitExit")
+       want := "no goroutines (main called runtime.Goexit) - deadlock!"
+       if !strings.Contains(output, want) {
+               t.Fatalf("output:\n%s\n\nwant output containing: %s", output, want)
+       }
+}
+
+func TestGoexitDefer(t *testing.T) {
+       c := make(chan struct{})
        go func() {
-               runtime.LockOSThread()
-               test(name)
-               c <- true
+               defer func() {
+                       r := recover()
+                       if r != nil {
+                               t.Errorf("non-nil recover during Goexit")
+                       }
+                       c <- struct{}{}
+               }()
+               runtime.Goexit()
        }()
+       // Note: if the defer fails to run, we will get a deadlock here
        <-c
 }
 
-func main() {
-       runtime.LockOSThread()
-       test("main")
-       testInNewThread("new-thread")
-       testInNewThread("second-new-thread")
-       test("main-again")
+func TestGoNil(t *testing.T) {
+       output := runTestProg(t, "testprog", "GoNil")
+       want := "go of nil func value"
+       if !strings.Contains(output, want) {
+               t.Fatalf("output:\n%s\n\nwant output containing: %s", output, want)
+       }
+}
+
+func TestMainGoroutineID(t *testing.T) {
+       output := runTestProg(t, "testprog", "MainGoroutineID")
+       want := "panic: test\n\ngoroutine 1 [running]:\n"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+func TestNoHelperGoroutines(t *testing.T) {
+       output := runTestProg(t, "testprog", "NoHelperGoroutines")
+       matches := regexp.MustCompile(`goroutine [0-9]+ \[`).FindAllStringSubmatch(output, -1)
+       if len(matches) != 1 || matches[0][0] != "goroutine 1 [" {
+               t.Fatalf("want to see only goroutine 1, see:\n%s", output)
+       }
+}
+
+func TestBreakpoint(t *testing.T) {
+       output := runTestProg(t, "testprog", "Breakpoint")
+       // If runtime.Breakpoint() is inlined, then the stack trace prints
+       // "runtime.Breakpoint(...)" instead of "runtime.Breakpoint()".
+       // For gccgo, no parens.
+       want := "runtime.Breakpoint"
+       if !strings.Contains(output, want) {
+               t.Fatalf("output:\n%s\n\nwant output containing: %s", output, want)
+       }
+}
+
+func TestGoexitInPanic(t *testing.T) {
+       // see issue 8774: this code used to trigger an infinite recursion
+       output := runTestProg(t, "testprog", "GoexitInPanic")
+       want := "fatal error: no goroutines (main called runtime.Goexit) - deadlock!"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+// Issue 14965: Runtime panics should be of type runtime.Error
+func TestRuntimePanicWithRuntimeError(t *testing.T) {
+       testCases := [...]func(){
+               0: func() {
+                       var m map[uint64]bool
+                       m[1234] = true
+               },
+               1: func() {
+                       ch := make(chan struct{})
+                       close(ch)
+                       close(ch)
+               },
+               2: func() {
+                       var ch = make(chan struct{})
+                       close(ch)
+                       ch <- struct{}{}
+               },
+               3: func() {
+                       var s = make([]int, 2)
+                       _ = s[2]
+               },
+               4: func() {
+                       n := -1
+                       _ = make(chan bool, n)
+               },
+               5: func() {
+                       close((chan bool)(nil))
+               },
+       }
+
+       for i, fn := range testCases {
+               got := panicValue(fn)
+               if _, ok := got.(runtime.Error); !ok {
+                       t.Errorf("test #%d: recovered value %v(type %T) does not implement runtime.Error", i, got, got)
+               }
+       }
+}
+
+func panicValue(fn func()) (recovered interface{}) {
+       defer func() {
+               recovered = recover()
+       }()
+       fn()
+       return
+}
+
+func TestPanicAfterGoexit(t *testing.T) {
+       // an uncaught panic should still work after goexit
+       output := runTestProg(t, "testprog", "PanicAfterGoexit")
+       want := "panic: hello"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+func TestRecoveredPanicAfterGoexit(t *testing.T) {
+       output := runTestProg(t, "testprog", "RecoveredPanicAfterGoexit")
+       want := "fatal error: no goroutines (main called runtime.Goexit) - deadlock!"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+func TestRecoverBeforePanicAfterGoexit(t *testing.T) {
+       t.Parallel()
+       output := runTestProg(t, "testprog", "RecoverBeforePanicAfterGoexit")
+       want := "fatal error: no goroutines (main called runtime.Goexit) - deadlock!"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+func TestRecoverBeforePanicAfterGoexit2(t *testing.T) {
+       t.Parallel()
+       output := runTestProg(t, "testprog", "RecoverBeforePanicAfterGoexit2")
+       want := "fatal error: no goroutines (main called runtime.Goexit) - deadlock!"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+func TestNetpollDeadlock(t *testing.T) {
+       if os.Getenv("GO_BUILDER_NAME") == "darwin-amd64-10_12" {
+               // A suspected kernel bug in macOS 10.12 occasionally results in
+               // an apparent deadlock when dialing localhost. The errors have not
+               // been observed on newer versions of the OS, so we don't plan to work
+               // around them. See https://golang.org/issue/22019.
+               testenv.SkipFlaky(t, 22019)
+       }
+
+       t.Parallel()
+       output := runTestProg(t, "testprognet", "NetpollDeadlock")
+       want := "done\n"
+       if !strings.HasSuffix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+func TestPanicTraceback(t *testing.T) {
+       t.Parallel()
+       output := runTestProg(t, "testprog", "PanicTraceback")
+       want := "panic: hello\n\tpanic: panic pt2\n\tpanic: panic pt1\n"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+
+       // Check functions in the traceback.
+       fns := []string{"main.pt1.func1", "panic", "main.pt2.func1", "panic", "main.pt2", "main.pt1"}
+       if runtime.Compiler == "gccgo" {
+               fns = []string{"main.pt1..func1", "panic", "main.pt2..func1", "panic", "main.pt2", "main.pt1"}
+       }
+       for _, fn := range fns {
+               var re *regexp.Regexp
+               if runtime.Compiler != "gccgo" {
+                       re = regexp.MustCompile(`(?m)^` + regexp.QuoteMeta(fn) + `\(.*\n`)
+               } else {
+                       re = regexp.MustCompile(`(?m)^` + regexp.QuoteMeta(fn) + `.*\n`)
+               }
+               idx := re.FindStringIndex(output)
+               if idx == nil {
+                       t.Fatalf("expected %q function in traceback:\n%s", fn, output)
+               }
+               output = output[idx[1]:]
+       }
+}
+
+func testPanicDeadlock(t *testing.T, name string, want string) {
+       // test issue 14432
+       output := runTestProg(t, "testprog", name)
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+func TestPanicDeadlockGosched(t *testing.T) {
+       testPanicDeadlock(t, "GoschedInPanic", "panic: errorThatGosched\n\n")
+}
+
+func TestPanicDeadlockSyscall(t *testing.T) {
+       testPanicDeadlock(t, "SyscallInPanic", "1\n2\npanic: 3\n\n")
+}
+
+func TestPanicLoop(t *testing.T) {
+       output := runTestProg(t, "testprog", "PanicLoop")
+       if want := "panic while printing panic value"; !strings.Contains(output, want) {
+               t.Errorf("output does not contain %q:\n%s", want, output)
+       }
+}
+
+func TestMemPprof(t *testing.T) {
+       testenv.MustHaveGoRun(t)
+       if runtime.Compiler == "gccgo" {
+               t.Skip("gccgo may not have the pprof tool")
+       }
+
+       exe, err := buildTestProg(t, "testprog")
+       if err != nil {
+               t.Fatal(err)
+       }
+
+       got, err := testenv.CleanCmdEnv(exec.Command(exe, "MemProf")).CombinedOutput()
+       if err != nil {
+               t.Fatal(err)
+       }
+       fn := strings.TrimSpace(string(got))
+       defer os.Remove(fn)
+
+       for try := 0; try < 2; try++ {
+               cmd := testenv.CleanCmdEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-alloc_space", "-top"))
+               // Check that pprof works both with and without explicit executable on command line.
+               if try == 0 {
+                       cmd.Args = append(cmd.Args, exe, fn)
+               } else {
+                       cmd.Args = append(cmd.Args, fn)
+               }
+               found := false
+               for i, e := range cmd.Env {
+                       if strings.HasPrefix(e, "PPROF_TMPDIR=") {
+                               cmd.Env[i] = "PPROF_TMPDIR=" + os.TempDir()
+                               found = true
+                               break
+                       }
+               }
+               if !found {
+                       cmd.Env = append(cmd.Env, "PPROF_TMPDIR="+os.TempDir())
+               }
+
+               top, err := cmd.CombinedOutput()
+               t.Logf("%s:\n%s", cmd.Args, top)
+               if err != nil {
+                       t.Error(err)
+               } else if !bytes.Contains(top, []byte("MemProf")) {
+                       t.Error("missing MemProf in pprof output")
+               }
+       }
+}
+
+var concurrentMapTest = flag.Bool("run_concurrent_map_tests", false, "also run flaky concurrent map tests")
+
+func TestConcurrentMapWrites(t *testing.T) {
+       if !*concurrentMapTest {
+               t.Skip("skipping without -run_concurrent_map_tests")
+       }
+       testenv.MustHaveGoRun(t)
+       output := runTestProg(t, "testprog", "concurrentMapWrites")
+       want := "fatal error: concurrent map writes"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+func TestConcurrentMapReadWrite(t *testing.T) {
+       if !*concurrentMapTest {
+               t.Skip("skipping without -run_concurrent_map_tests")
+       }
+       testenv.MustHaveGoRun(t)
+       output := runTestProg(t, "testprog", "concurrentMapReadWrite")
+       want := "fatal error: concurrent map read and map write"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+func TestConcurrentMapIterateWrite(t *testing.T) {
+       if !*concurrentMapTest {
+               t.Skip("skipping without -run_concurrent_map_tests")
+       }
+       testenv.MustHaveGoRun(t)
+       output := runTestProg(t, "testprog", "concurrentMapIterateWrite")
+       want := "fatal error: concurrent map iteration and map write"
+       if !strings.HasPrefix(output, want) {
+               t.Fatalf("output does not start with %q:\n%s", want, output)
+       }
+}
+
+type point struct {
+       x, y *int
+}
+
+func (p *point) negate() {
+       *p.x = *p.x * -1
+       *p.y = *p.y * -1
+}
+
+// Test for issue #10152.
+func TestPanicInlined(t *testing.T) {
+       defer func() {
+               r := recover()
+               if r == nil {
+                       t.Fatalf("recover failed")
+               }
+               buf := make([]byte, 2048)
+               n := runtime.Stack(buf, false)
+               buf = buf[:n]
+               want := []byte("(*point).negate(")
+               if runtime.Compiler == "gccgo" {
+                       want = []byte("point.negate")
+               }
+               if !bytes.Contains(buf, want) {
+                       t.Logf("%s", buf)
+                       t.Fatalf("expecting stack trace to contain call to %s", want)
+               }
+       }()
+
+       pt := new(point)
+       pt.negate()
+}
+
+// Test for issues #3934 and #20018.
+// We want to delay exiting until a panic print is complete.
+func TestPanicRace(t *testing.T) {
+       testenv.MustHaveGoRun(t)
+
+       exe, err := buildTestProg(t, "testprog")
+       if err != nil {
+               t.Fatal(err)
+       }
+
+       // The test is intentionally racy, and in my testing does not
+       // produce the expected output about 0.05% of the time.
+       // So run the program in a loop and only fail the test if we
+       // get the wrong output ten times in a row.
+       const tries = 10
+retry:
+       for i := 0; i < tries; i++ {
+               got, err := testenv.CleanCmdEnv(exec.Command(exe, "PanicRace")).CombinedOutput()
+               if err == nil {
+                       t.Logf("try %d: program exited successfully, should have failed", i+1)
+                       continue
+               }
+
+               if i > 0 {
+                       t.Logf("try %d:\n", i+1)
+               }
+               t.Logf("%s\n", got)
+
+               wants := []string{
+                       "panic: crash",
+                       "PanicRace",
+                       "created by ",
+               }
+               if runtime.Compiler == "gccgo" {
+                       // gccgo will dump a function name like main.$nested30.
+                       // Match on the file name instead.
+                       wants[1] = "panicrace"
+               }
+               for _, want := range wants {
+                       if !bytes.Contains(got, []byte(want)) {
+                               t.Logf("did not find expected string %q", want)
+                               continue retry
+                       }
+               }
+
+               // Test generated expected output.
+               return
+       }
+       t.Errorf("test ran %d times without producing expected output", tries)
+}
+
+func TestBadTraceback(t *testing.T) {
+       if runtime.Compiler == "gccgo" {
+               t.Skip("gccgo does not do a hex dump")
+       }
+       output := runTestProg(t, "testprog", "BadTraceback")
+       for _, want := range []string{
+               "runtime: unexpected return pc",
+               "called from 0xbad",
+               "00000bad",    // Smashed LR in hex dump
+               "<main.badLR", // Symbolization in hex dump (badLR1 or badLR2)
+       } {
+               if !strings.Contains(output, want) {
+                       t.Errorf("output does not contain %q:\n%s", want, output)
+               }
+       }
+}
+
+func TestTimePprof(t *testing.T) {
+       if runtime.Compiler == "gccgo" {
+               t.Skip("gccgo may not have the pprof tool")
+       }
+       if runtime.GOOS == "aix" {
+               t.Skip("pprof not yet available on AIX (see golang.org/issue/28555)")
+       }
+       fn := runTestProg(t, "testprog", "TimeProf")
+       fn = strings.TrimSpace(fn)
+       defer os.Remove(fn)
+
+       cmd := testenv.CleanCmdEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-top", "-nodecount=1", fn))
+       cmd.Env = append(cmd.Env, "PPROF_TMPDIR="+os.TempDir())
+       top, err := cmd.CombinedOutput()
+       t.Logf("%s", top)
+       if err != nil {
+               t.Error(err)
+       } else if bytes.Contains(top, []byte("ExternalCode")) {
+               t.Error("profiler refers to ExternalCode")
+       }
+}
+
+// Test that runtime.abort does so.
+func TestAbort(t *testing.T) {
+       // Pass GOTRACEBACK to ensure we get runtime frames.
+       output := runTestProg(t, "testprog", "Abort", "GOTRACEBACK=system")
+       if want := "runtime.abort"; !strings.Contains(output, want) {
+               t.Errorf("output does not contain %q:\n%s", want, output)
+       }
+       if strings.Contains(output, "BAD") {
+               t.Errorf("output contains BAD:\n%s", output)
+       }
+       // Check that it's a signal traceback.
+       want := "PC="
+       // For systems that use a breakpoint, check specifically for that.
+       if runtime.Compiler == "gc" {
+               switch runtime.GOARCH {
+               case "386", "amd64":
+                       switch runtime.GOOS {
+                       case "plan9":
+                               want = "sys: breakpoint"
+                       case "windows":
+                               want = "Exception 0x80000003"
+                       default:
+                               want = "SIGTRAP"
+                       }
+               }
+       }
+       if !strings.Contains(output, want) {
+               t.Errorf("output does not contain %q:\n%s", want, output)
+       }
+}
+
+// For TestRuntimePanic: test a panic in the runtime package without
+// involving the testing harness.
+func init() {
+       if os.Getenv("GO_TEST_RUNTIME_PANIC") == "1" {
+               defer func() {
+                       if r := recover(); r != nil {
+                               // We expect to crash, so exit 0
+                               // to indicate failure.
+                               os.Exit(0)
+                       }
+               }()
+               runtime.PanicForTesting(nil, 1)
+               // We expect to crash, so exit 0 to indicate failure.
+               os.Exit(0)
+       }
+}
+
+func TestRuntimePanic(t *testing.T) {
+       testenv.MustHaveExec(t)
+       cmd := testenv.CleanCmdEnv(exec.Command(os.Args[0], "-test.run=TestRuntimePanic"))
+       cmd.Env = append(cmd.Env, "GO_TEST_RUNTIME_PANIC=1")
+       out, err := cmd.CombinedOutput()
+       t.Logf("%s", out)
+       if err == nil {
+               t.Error("child process did not fail")
+       } else if want := "runtime.unexportedPanicForTesting"; !bytes.Contains(out, []byte(want)) {
+               t.Errorf("output did not contain expected string %q", want)
+       }
+}
+
+// Test that g0 stack overflows are handled gracefully.
+func TestG0StackOverflow(t *testing.T) {
+       testenv.MustHaveExec(t)
+
+       switch runtime.GOOS {
+       case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "android":
+               t.Skipf("g0 stack is wrong on pthread platforms (see golang.org/issue/26061)")
+       }
+
+       if os.Getenv("TEST_G0_STACK_OVERFLOW") != "1" {
+               cmd := testenv.CleanCmdEnv(exec.Command(os.Args[0], "-test.run=TestG0StackOverflow", "-test.v"))
+               cmd.Env = append(cmd.Env, "TEST_G0_STACK_OVERFLOW=1")
+               out, err := cmd.CombinedOutput()
+               // Don't check err since it's expected to crash.
+               if n := strings.Count(string(out), "morestack on g0\n"); n != 1 {
+                       t.Fatalf("%s\n(exit status %v)", out, err)
+               }
+               // Check that it's a signal-style traceback.
+               if runtime.GOOS != "windows" {
+                       if want := "PC="; !strings.Contains(string(out), want) {
+                               t.Errorf("output does not contain %q:\n%s", want, out)
+                       }
+               }
+               return
+       }
+
+       runtime.G0StackOverflow()
+}
+
+// Test that panic message is not clobbered.
+// See issue 30150.
+func TestDoublePanic(t *testing.T) {
+       output := runTestProg(t, "testprog", "DoublePanic", "GODEBUG=clobberfree=1")
+       wants := []string{"panic: XXX", "panic: YYY"}
+       for _, want := range wants {
+               if !strings.Contains(output, want) {
+                       t.Errorf("output:\n%s\n\nwant output containing: %s", output, want)
+               }
+       }
 }
-`