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"}
	for _, fn := range fns {

	// sameId reports whether obj.Id() and Id(pkg, name) are the same.
	// If foldCase is true, names are considered equal if they are equal with case folding
	// and their packages are ignored (e.g., pkg1.m, pkg1.M, pkg2.m, and pkg2.M are all equal).
	sameId(pkg *Package, name string, foldCase bool) bool

	// scopePos returns the start position of the scope of this Object
	scopePos() token.Pos

	if c.vers == VersionTLS13 {
		payloadBytes-- // encrypted ContentType
	}

	// Allow packet growth in arithmetic progression up to max.
	pkt := c.packetsSent
	c.packetsSent++
	if pkt > 1000 {
		return maxPlaintext // avoid overflow in multiply below
	}

	n := payloadBytes * int(pkt+1)
	if n > maxPlaintext {
		n = maxPlaintext
	}
	return n
}

func (c *Conn) write(data []byte) (int, error) {

	defer mux.mu.Unlock()
	// Check for conflict.
	if err := mux.index.possiblyConflictingPatterns(pat, func(pat2 *pattern) error {
		if pat.conflictsWith(pat2) {
			d := describeConflict(pat, pat2)
			return fmt.Errorf("pattern %q (registered at %s) conflicts with pattern %q (registered at %s):\n%s",
				pat, pat.loc, pat2, pat2.loc, d)
		}
		return nil
	}); err != nil {
		return err
	}

		register1(test)
		return
	}
	// TODO(dmitshur,austin): It might be better to unify the execution of 'go test pkg'
	// invocations for the same variant to be done with a single 'go test pkg1 pkg2 pkg3'
	// command, just like it's already done in registerStdTest and registerRaceBenchTest.
	// Those methods accumulate matched packages in stdMatches and benchMatches slices,

				intrinsics[intrinsicKey{a, pkg, fn}] = b
			}
		}
	}
	// alias defines pkg.fn = pkg2.fn2 for all architectures in archs for which pkg2.fn2 exists.
	alias := func(pkg, fn, pkg2, fn2 string, archs ...*sys.Arch) {
		aliased := false
		for _, a := range archs {
			if b, ok := intrinsics[intrinsicKey{a, pkg2, fn2}]; ok {
				intrinsics[intrinsicKey{a, pkg, fn}] = b
				aliased = true
			}
		}