ok:       false,
			out:      "+A\n+C\n+E\n+F\n",
		},
		{
			name:     "feature removed",
			features: []string{"C", "A"},
			required: []string{"A", "B", "C"},
			ok:       false,
			out:      "-B\n",
		},
		{
			name:      "exception removal",
			features:  []string{"A", "C"},
			required:  []string{"A", "B", "C"},
			exception: []string{"B"},
			ok:        true,

			// We are starting so many processes that on
			// some systems (problem seen on Darwin,
			// Dragonfly, OpenBSD) the fork call will fail
			// with EAGAIN.
			if pe, ok := err.(*os.PathError); ok {
				err = pe.Err
			}
			if se, ok := err.(syscall.Errno); ok && (se == syscall.EAGAIN || se == syscall.EMFILE) {
				time.Sleep(time.Millisecond)
				continue
			}

			t.Error(err)
			return
		}

reserved.
L2::: Use of this source code is governed by a BSD-style
L3::: license that can be found in the LICENSE file.
L4:
L5:@echo off
L6:
L7:setlocal
L8:
L9:if exist make.bat goto ok
L10:echo all.bat must be run from go\src
L11::: cannot exit: would kill parent command interpreter
L12:goto end
L13::ok
L14:
L15:call .\make.bat --no-banner --no-local
L16:if %GOBUILDFAIL%==1 goto end
L17:call .\run.bat --no-rebuild --no-local
L18:if %GOBUILDFAIL%==1 goto end
L19:"%GOTOOLDIR%/dist" banner
...

		fatal("usage: callback testname")
	}
	switch os.Args[1] {
	default:
		fatal("unknown test %q", os.Args[1])
	case "Call":
		testCall()
	case "Callback":
		testCallback()
	}
	println("OK")
}

func fatal(f string, args ...any) {
	fmt.Fprintln(os.Stderr, fmt.Sprintf(f, args...))
	os.Exit(1)
}

type GoCallback struct{}

func (p *GoCallback) Run() string {
	return "GoCallback.Run"
}

			// reports errors to parser.Errorf
			if ok {
				obj.Flushplist(ctxt, pList, nil)
			}
		}
		if !ok {
			failedFile = f
			break
		}
	}
	if ok && !*flags.SymABIs {
		ctxt.NumberSyms()
		obj.WriteObjFile(ctxt, buf)
	}
	if !ok || diag {
		if failedFile != "" {
			log.Printf("assembly of %s failed", failedFile)
		} else {
			log.Print("assembly failed")
		}

		cmd.Env = append(cmd.Environ(),
			"CGO_CFLAGS="+cflags,
			"CGO_CXXFLAGS="+cflags,
			"CGO_LDFLAGS="+cflags)
	}
	out, err := cmd.CombinedOutput()
	if string(out) != "OK\n" {
		t.Errorf("%s", string(out))
	}
	if err != nil {
		t.Errorf("%s", err)
	}
}

func mustHaveCxx(t *testing.T) {
	// Ask the go tool for the CXX it's configured to use.

		panic("compressor already registered")
	}
}

func compressor(method uint16) Compressor {
	ci, ok := compressors.Load(method)
	if !ok {
		return nil
	}
	return ci.(Compressor)
}

func decompressor(method uint16) Decompressor {
	di, ok := decompressors.Load(method)
	if !ok {
		return nil
	}
	return di.(Decompressor)

	// except in the definition (handled at end of function).
	refName := make(map[*ast.Expr]*Name)
	for _, r := range f.Ref {
		refName[r.Expr] = r.Name
	}
	for _, d := range f.AST.Decls {
		d, ok := d.(*ast.GenDecl)
		if !ok || d.Tok != token.TYPE {
			continue
		}
		for _, s := range d.Specs {
			s := s.(*ast.TypeSpec)
			n := refName[&s.Type]
			if n != nil && n.Mangle != "" {
				override[n.Mangle] = s.Name.Name
			}

// we return the opcode for MRC so that asm doesn't need to import obj/arm.
func ARMMRCOffset(op obj.As, cond string, x0, x1, x2, x3, x4, x5 int64) (offset int64, op0 obj.As, ok bool) {
	op1 := int64(0)
	if op == arm.AMRC {
		op1 = 1
	}
	bits, ok := ParseARMCondition(cond)
	if !ok {
		return
	}
	offset = (0xe << 24) | // opcode
		(op1 << 20) | // MCR/MRC
		((int64(bits) ^ arm.C_SCOND_XOR) << 28) | // scond

func crawl(url string, sourceURL string) {
	if strings.Contains(url, "/devel/release") {
		return
	}
	mu.Lock()
	defer mu.Unlock()
	if u, frag, ok := strings.Cut(url, "#"); ok {
		url = u
		if frag != "" {
			uf := urlFrag{url, frag}
			neededFrags[uf] = append(neededFrags[uf], sourceURL)
		}
	}
	if crawled[url] {
		return
	}
	crawled[url] = true

	wg.Add(1)