cmd/vendor: update x/tools to v0.20.1-0.20240429173604-74c9cfe4d22f

The golang.org/x/tools/go/analysis/passes/stdversion was forcibly
added by means of an import in a throwaway file not committed.

Change-Id: I194012ae354f6f8d2d0c1fa39612e5554a4ab1cf
Reviewed-on: https://go-review.googlesource.com/c/go/+/582555
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

src/cmd/go.mod

@@ -6,12 +6,12 @@ require (
 	github.com/google/pprof v0.0.0-20240207164012-fb44976bdcd5
 	golang.org/x/arch v0.7.0
 	golang.org/x/build v0.0.0-20240222153247-cf4ed81bb19f
-	golang.org/x/mod v0.16.0
-	golang.org/x/sync v0.6.0
+	golang.org/x/mod v0.17.0
+	golang.org/x/sync v0.7.0
 	golang.org/x/sys v0.19.0
 	golang.org/x/telemetry v0.0.0-20240401194020-3640ba572dd1
 	golang.org/x/term v0.18.0
-	golang.org/x/tools v0.19.1-0.20240329171618-904c6baa6e14
+	golang.org/x/tools v0.20.1-0.20240429173604-74c9cfe4d22f
 )
 
 require (

src/cmd/go.sum

@@ -26,10 +26,10 @@ golang.org/x/arch v0.7.0 h1:pskyeJh/3AmoQ8CPE95vxHLqp1G1GfGNXTmcl9NEKTc=
 golang.org/x/arch v0.7.0/go.mod h1:FEVrYAQjsQXMVJ1nsMoVVXPZg6p2JE2mx8psSWTDQys=
 golang.org/x/build v0.0.0-20240222153247-cf4ed81bb19f h1:XQ2eu0I26WsNCKQkRehp+5mwjjChw94trD9LT8LLSq0=
 golang.org/x/build v0.0.0-20240222153247-cf4ed81bb19f/go.mod h1:HTqTCkubWT8epEK9hDWWGkoOOB7LGSrU1qvWZCSwO50=
-golang.org/x/mod v0.16.0 h1:QX4fJ0Rr5cPQCF7O9lh9Se4pmwfwskqZfq5moyldzic=
-golang.org/x/mod v0.16.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
-golang.org/x/sync v0.6.0 h1:5BMeUDZ7vkXGfEr1x9B4bRcTH4lpkTkpdh0T/J+qjbQ=
-golang.org/x/sync v0.6.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/mod v0.17.0 h1:zY54UmvipHiNd+pm+m0x9KhZ9hl1/7QNMyxXbc6ICqA=
+golang.org/x/mod v0.17.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
+golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
+golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.19.0 h1:q5f1RH2jigJ1MoAWp2KTp3gm5zAGFUTarQZ5U386+4o=
 golang.org/x/sys v0.19.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/telemetry v0.0.0-20240401194020-3640ba572dd1 h1:x0E096pmZoLhjEfcM4q2gJ3eZvnTpZiYDSPDYtm4wME=
@@ -38,7 +38,7 @@ golang.org/x/term v0.18.0 h1:FcHjZXDMxI8mM3nwhX9HlKop4C0YQvCVCdwYl2wOtE8=
 golang.org/x/term v0.18.0/go.mod h1:ILwASektA3OnRv7amZ1xhE/KTR+u50pbXfZ03+6Nx58=
 golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
 golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
-golang.org/x/tools v0.19.1-0.20240329171618-904c6baa6e14 h1:apiqzCtEqbg/NjzevIbwubwnRo7WZDOgdr8s6ZvIKi0=
-golang.org/x/tools v0.19.1-0.20240329171618-904c6baa6e14/go.mod h1:qoJWxmGSIBmAeriMx19ogtrEPrGtDbPK634QFIcLAhc=
+golang.org/x/tools v0.20.1-0.20240429173604-74c9cfe4d22f h1:VNKRNwDFpvmQ9DziicBj7Xs8Xr9zFtHVVCccBLiV+nI=
+golang.org/x/tools v0.20.1-0.20240429173604-74c9cfe4d22f/go.mod h1:EUhO3BJA9eB8d9EAsGPjXxkzI1Rl/NRgB9zrdAzyoWI=
 rsc.io/markdown v0.0.0-20240117044121-669d2fdf1650 h1:fuOABZYWclLVNotDsHVaFixLdtoC7+UQZJ0KSC1ocm0=
 rsc.io/markdown v0.0.0-20240117044121-669d2fdf1650/go.mod h1:8xcPgWmwlZONN1D9bjxtHEjrUtSEa3fakVF8iaewYKQ=

src/cmd/vendor/golang.org/x/mod/modfile/read.go

@@ -225,7 +225,7 @@ func (x *FileSyntax) Cleanup() {
 			if ww == 0 {
 				continue
 			}
-			if ww == 1 {
+			if ww == 1 && len(stmt.RParen.Comments.Before) == 0 {
 				// Collapse block into single line.
 				line := &Line{
 					Comments: Comments{

src/cmd/vendor/golang.org/x/mod/modfile/rule.go

@@ -975,6 +975,8 @@ func (f *File) AddGoStmt(version string) error {
 		var hint Expr
 		if f.Module != nil && f.Module.Syntax != nil {
 			hint = f.Module.Syntax
+		} else if f.Syntax == nil {
+			f.Syntax = new(FileSyntax)
 		}
 		f.Go = &Go{
 			Version: version,

src/cmd/vendor/golang.org/x/mod/sumdb/tlog/tile.go

@@ -115,16 +115,14 @@ func NewTiles(h int, oldTreeSize, newTreeSize int64) []Tile {
 	for level := uint(0); newTreeSize>>(H*level) > 0; level++ {
 		oldN := oldTreeSize >> (H * level)
 		newN := newTreeSize >> (H * level)
+		if oldN == newN {
+			continue
+		}
 		for n := oldN >> H; n < newN>>H; n++ {
 			tiles = append(tiles, Tile{H: h, L: int(level), N: n, W: 1 << H})
 		}
 		n := newN >> H
-		maxW := int(newN - n<<H)
-		minW := 1
-		if oldN > n<<H {
-			minW = int(oldN - n<<H)
-		}
-		for w := minW; w <= maxW; w++ {
+		if w := int(newN - n<<H); w > 0 {
 			tiles = append(tiles, Tile{H: h, L: int(level), N: n, W: w})
 		}
 	}

src/cmd/vendor/golang.org/x/sync/semaphore/semaphore.go

@@ -35,11 +35,25 @@ type Weighted struct {
 // Acquire acquires the semaphore with a weight of n, blocking until resources
 // are available or ctx is done. On success, returns nil. On failure, returns
 // ctx.Err() and leaves the semaphore unchanged.
-//
-// If ctx is already done, Acquire may still succeed without blocking.
 func (s *Weighted) Acquire(ctx context.Context, n int64) error {
+	done := ctx.Done()
+
 	s.mu.Lock()
+	select {
+	case <-done:
+		// ctx becoming done has "happened before" acquiring the semaphore,
+		// whether it became done before the call began or while we were
+		// waiting for the mutex. We prefer to fail even if we could acquire
+		// the mutex without blocking.
+		s.mu.Unlock()
+		return ctx.Err()
+	default:
+	}
 	if s.size-s.cur >= n && s.waiters.Len() == 0 {
+		// Since we hold s.mu and haven't synchronized since checking done, if
+		// ctx becomes done before we return here, it becoming done must have
+		// "happened concurrently" with this call - it cannot "happen before"
+		// we return in this branch. So, we're ok to always acquire here.
 		s.cur += n
 		s.mu.Unlock()
 		return nil
@@ -48,7 +62,7 @@ func (s *Weighted) Acquire(ctx context.Context, n int64) error {
 	if n > s.size {
 		// Don't make other Acquire calls block on one that's doomed to fail.
 		s.mu.Unlock()
-		<-ctx.Done()
+		<-done
 		return ctx.Err()
 	}
 
@@ -58,14 +72,14 @@ func (s *Weighted) Acquire(ctx context.Context, n int64) error {
 	s.mu.Unlock()
 
 	select {
-	case <-ctx.Done():
-		err := ctx.Err()
+	case <-done:
 		s.mu.Lock()
 		select {
 		case <-ready:
-			// Acquired the semaphore after we were canceled.  Rather than trying to
-			// fix up the queue, just pretend we didn't notice the cancelation.
-			err = nil
+			// Acquired the semaphore after we were canceled.
+			// Pretend we didn't and put the tokens back.
+			s.cur -= n
+			s.notifyWaiters()
 		default:
 			isFront := s.waiters.Front() == elem
 			s.waiters.Remove(elem)
@@ -75,9 +89,19 @@ func (s *Weighted) Acquire(ctx context.Context, n int64) error {
 			}
 		}
 		s.mu.Unlock()
-		return err
+		return ctx.Err()
 
 	case <-ready:
+		// Acquired the semaphore. Check that ctx isn't already done.
+		// We check the done channel instead of calling ctx.Err because we
+		// already have the channel, and ctx.Err is O(n) with the nesting
+		// depth of ctx.
+		select {
+		case <-done:
+			s.Release(n)
+			return ctx.Err()
+		default:
+		}
 		return nil
 	}
 }

src/cmd/vendor/golang.org/x/tools/go/analysis/analysis.go

@@ -112,6 +112,19 @@ type Pass struct {
 	// analysis's ResultType.
 	ResultOf map[*Analyzer]interface{}
 
+	// ReadFile returns the contents of the named file.
+	//
+	// The only valid file names are the elements of OtherFiles
+	// and IgnoredFiles, and names returned by
+	// Fset.File(f.FileStart).Name() for each f in Files.
+	//
+	// Analyzers must use this function (if provided) instead of
+	// accessing the file system directly. This allows a driver to
+	// provide a virtualized file tree (including, for example,
+	// unsaved editor buffers) and to track dependencies precisely
+	// to avoid unnecessary recomputation.
+	ReadFile func(filename string) ([]byte, error)
+
 	// -- facts --
 
 	// ImportObjectFact retrieves a fact associated with obj.

src/cmd/vendor/golang.org/x/tools/go/analysis/doc.go

@@ -32,7 +32,7 @@ bases, and so on.
 
 # Analyzer
 
-The primary type in the API is Analyzer. An Analyzer statically
+The primary type in the API is [Analyzer]. An Analyzer statically
 describes an analysis function: its name, documentation, flags,
 relationship to other analyzers, and of course, its logic.
 
@@ -72,7 +72,7 @@ help that describes the analyses it performs.
 The doc comment contains a brief one-line summary,
 optionally followed by paragraphs of explanation.
 
-The Analyzer type has more fields besides those shown above:
+The [Analyzer] type has more fields besides those shown above:
 
 	type Analyzer struct {
 		Name             string
@@ -114,7 +114,7 @@ instance of the Pass type.
 
 # Pass
 
-A Pass describes a single unit of work: the application of a particular
+A [Pass] describes a single unit of work: the application of a particular
 Analyzer to a particular package of Go code.
 The Pass provides information to the Analyzer's Run function about the
 package being analyzed, and provides operations to the Run function for
@@ -135,16 +135,14 @@ reporting diagnostics and other information back to the driver.
 The Fset, Files, Pkg, and TypesInfo fields provide the syntax trees,
 type information, and source positions for a single package of Go code.
 
-The OtherFiles field provides the names, but not the contents, of non-Go
-files such as assembly that are part of this package. See the "asmdecl"
-or "buildtags" analyzers for examples of loading non-Go files and reporting
-diagnostics against them.
-
-The IgnoredFiles field provides the names, but not the contents,
-of ignored Go and non-Go source files that are not part of this package
-with the current build configuration but may be part of other build
-configurations. See the "buildtags" analyzer for an example of loading
-and checking IgnoredFiles.
+The OtherFiles field provides the names of non-Go
+files such as assembly that are part of this package.
+Similarly, the IgnoredFiles field provides the names of Go and non-Go
+source files that are not part of this package with the current build
+configuration but may be part of other build configurations.
+The contents of these files may be read using Pass.ReadFile;
+see the "asmdecl" or "buildtags" analyzers for examples of loading
+non-Go files and reporting diagnostics against them.
 
 The ResultOf field provides the results computed by the analyzers
 required by this one, as expressed in its Analyzer.Requires field. The
@@ -177,7 +175,7 @@ Diagnostic is defined as:
 The optional Category field is a short identifier that classifies the
 kind of message when an analysis produces several kinds of diagnostic.
 
-The Diagnostic struct does not have a field to indicate its severity
+The [Diagnostic] struct does not have a field to indicate its severity
 because opinions about the relative importance of Analyzers and their
 diagnostics vary widely among users. The design of this framework does
 not hold each Analyzer responsible for identifying the severity of its
@@ -191,7 +189,7 @@ and buildtag, inspect the raw text of Go source files or even non-Go
 files such as assembly. To report a diagnostic against a line of a
 raw text file, use the following sequence:
 
-	content, err := os.ReadFile(filename)
+	content, err := pass.ReadFile(filename)
 	if err != nil { ... }
 	tf := fset.AddFile(filename, -1, len(content))
 	tf.SetLinesForContent(content)
@@ -216,7 +214,7 @@ addition, it records which functions are printf wrappers for use by
 later analysis passes to identify other printf wrappers by induction.
 A result such as “f is a printf wrapper” that is not interesting by
 itself but serves as a stepping stone to an interesting result (such as
-a diagnostic) is called a "fact".
+a diagnostic) is called a [Fact].
 
 The analysis API allows an analysis to define new types of facts, to
 associate facts of these types with objects (named entities) declared

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go

@@ -173,7 +173,7 @@ func run(pass *analysis.Pass) (interface{}, error) {
 
 Files:
 	for _, fname := range sfiles {
-		content, tf, err := analysisutil.ReadFile(pass.Fset, fname)
+		content, tf, err := analysisutil.ReadFile(pass, fname)
 		if err != nil {
 			return nil, err
 		}

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/buildtag/buildtag.go

@@ -89,7 +89,7 @@ func checkOtherFile(pass *analysis.Pass, filename string) error {
 
 	// We cannot use the Go parser, since this may not be a Go source file.
 	// Read the raw bytes instead.
-	content, tf, err := analysisutil.ReadFile(pass.Fset, filename)
+	content, tf, err := analysisutil.ReadFile(pass, filename)
 	if err != nil {
 		return err
 	}

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/buildtag/buildtag_old.go

@@ -83,7 +83,7 @@ func checkGoFile(pass *analysis.Pass, f *ast.File) {
 }
 
 func checkOtherFile(pass *analysis.Pass, filename string) error {
-	content, tf, err := analysisutil.ReadFile(pass.Fset, filename)
+	content, tf, err := analysisutil.ReadFile(pass, filename)
 	if err != nil {
 		return err
 	}

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/directive/directive.go

@@ -90,7 +90,7 @@ func checkGoFile(pass *analysis.Pass, f *ast.File) {
 func checkOtherFile(pass *analysis.Pass, filename string) error {
 	// We cannot use the Go parser, since is not a Go source file.
 	// Read the raw bytes instead.
-	content, tf, err := analysisutil.ReadFile(pass.Fset, filename)
+	content, tf, err := analysisutil.ReadFile(pass, filename)
 	if err != nil {
 		return err
 	}

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/framepointer/framepointer.go

@@ -48,7 +48,7 @@ func run(pass *analysis.Pass) (interface{}, error) {
 	}
 
 	for _, fname := range sfiles {
-		content, tf, err := analysisutil.ReadFile(pass.Fset, fname)
+		content, tf, err := analysisutil.ReadFile(pass, fname)
 		if err != nil {
 			return nil, err
 		}

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/internal/analysisutil/util.go

@@ -14,6 +14,7 @@ import (
 	"go/types"
 	"os"
 
+	"golang.org/x/tools/go/analysis"
 	"golang.org/x/tools/internal/aliases"
 	"golang.org/x/tools/internal/analysisinternal"
 )
@@ -60,12 +61,16 @@ func HasSideEffects(info *types.Info, e ast.Expr) bool {
 
 // ReadFile reads a file and adds it to the FileSet
 // so that we can report errors against it using lineStart.
-func ReadFile(fset *token.FileSet, filename string) ([]byte, *token.File, error) {
-	content, err := os.ReadFile(filename)
+func ReadFile(pass *analysis.Pass, filename string) ([]byte, *token.File, error) {
+	readFile := pass.ReadFile
+	if readFile == nil {
+		readFile = os.ReadFile
+	}
+	content, err := readFile(filename)
 	if err != nil {
 		return nil, nil, err
 	}
-	tf := fset.AddFile(filename, -1, len(content))
+	tf := pass.Fset.AddFile(filename, -1, len(content))
 	tf.SetLinesForContent(content)
 	return content, tf, nil
 }

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/doc.go

@@ -11,29 +11,73 @@
 //
 // The check applies to calls of the formatting functions such as
 // [fmt.Printf] and [fmt.Sprintf], as well as any detected wrappers of
-// those functions.
-//
-// In this example, the %d format operator requires an integer operand:
-//
-//	fmt.Printf("%d", "hello") // fmt.Printf format %d has arg "hello" of wrong type string
+// those functions such as [log.Printf]. It reports a variety of
+// mistakes such as syntax errors in the format string and mismatches
+// (of number and type) between the verbs and their arguments.
 //
 // See the documentation of the fmt package for the complete set of
 // format operators and their operand types.
 //
+// # Examples
+//
+// The %d format operator requires an integer operand.
+// Here it is incorrectly applied to a string:
+//
+//	fmt.Printf("%d", "hello") // fmt.Printf format %d has arg "hello" of wrong type string
+//
+// A call to Printf must have as many operands as there are "verbs" in
+// the format string, not too few:
+//
+//	fmt.Printf("%d") // fmt.Printf format reads arg 1, but call has 0 args
+//
+// nor too many:
+//
+//	fmt.Printf("%d", 1, 2) // fmt.Printf call needs 1 arg, but has 2 args
+//
+// Explicit argument indexes must be no greater than the number of
+// arguments:
+//
+//	fmt.Printf("%[3]d", 1, 2) // fmt.Printf call has invalid argument index 3
+//
+// The checker also uses a heuristic to report calls to Print-like
+// functions that appear to have been intended for their Printf-like
+// counterpart:
+//
+//	log.Print("%d", 123) // log.Print call has possible formatting directive %d
+//
+// # Inferred printf wrappers
+//
+// Functions that delegate their arguments to fmt.Printf are
+// considered "printf wrappers"; calls to them are subject to the same
+// checking. In this example, logf is a printf wrapper:
+//
+//	func logf(level int, format string, args ...any) {
+//		if enabled(level) {
+//			log.Printf(format, args...)
+//		}
+//	}
+//
+//	logf(3, "invalid request: %v") // logf format reads arg 1, but call has 0 args
+//
 // To enable printf checking on a function that is not found by this
 // analyzer's heuristics (for example, because control is obscured by
 // dynamic method calls), insert a bogus call:
 //
 //	func MyPrintf(format string, args ...any) {
 //		if false {
-//			_ = fmt.Sprintf(format, args...) // enable printf checker
+//			_ = fmt.Sprintf(format, args...) // enable printf checking
 //		}
 //		...
 //	}
 //
-// The -funcs flag specifies a comma-separated list of names of additional
-// known formatting functions or methods. If the name contains a period,
-// it must denote a specific function using one of the following forms:
+// # Specifying printf wrappers by flag
+//
+// The -funcs flag specifies a comma-separated list of names of
+// additional known formatting functions or methods. (This legacy flag
+// is rarely used due to the automatic inference described above.)
+//
+// If the name contains a period, it must denote a specific function
+// using one of the following forms:
 //
 //	dir/pkg.Function
 //	dir/pkg.Type.Method

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/stdversion/stdversion.go

@@ -0,0 +1,159 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package stdversion reports uses of standard library symbols that are
+// "too new" for the Go version in force in the referring file.
+package stdversion
+
+import (
+	"go/ast"
+	"go/build"
+	"go/types"
+	"regexp"
+
+	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/analysis/passes/inspect"
+	"golang.org/x/tools/go/ast/inspector"
+	"golang.org/x/tools/internal/typesinternal"
+	"golang.org/x/tools/internal/versions"
+)
+
+const Doc = `report uses of too-new standard library symbols
+
+The stdversion analyzer reports references to symbols in the standard
+library that were introduced by a Go release higher than the one in
+force in the referring file. (Recall that the file's Go version is
+defined by the 'go' directive its module's go.mod file, or by a
+"//go:build go1.X" build tag at the top of the file.)
+
+The analyzer does not report a diagnostic for a reference to a "too
+new" field or method of a type that is itself "too new", as this may
+have false positives, for example if fields or methods are accessed
+through a type alias that is guarded by a Go version constraint.
+`
+
+var Analyzer = &analysis.Analyzer{
+	Name:             "stdversion",
+	Doc:              Doc,
+	Requires:         []*analysis.Analyzer{inspect.Analyzer},
+	URL:              "https://pkg.go.dev/golang.org/x/tools/go/analysis/passes/stdversion",
+	RunDespiteErrors: true,
+	Run:              run,
+}
+
+func run(pass *analysis.Pass) (any, error) {
+	// Prior to go1.22, versions.FileVersion returns only the
+	// toolchain version, which is of no use to us, so
+	// disable this analyzer on earlier versions.
+	if !slicesContains(build.Default.ReleaseTags, "go1.22") {
+		return nil, nil
+	}
+
+	// Don't report diagnostics for modules marked before go1.21,
+	// since at that time the go directive wasn't clearly
+	// specified as a toolchain requirement.
+	//
+	// TODO(adonovan): after go1.21, call GoVersion directly.
+	pkgVersion := any(pass.Pkg).(interface{ GoVersion() string }).GoVersion()
+	if !versions.AtLeast(pkgVersion, "go1.21") {
+		return nil, nil
+	}
+
+	// disallowedSymbols returns the set of standard library symbols
+	// in a given package that are disallowed at the specified Go version.
+	type key struct {
+		pkg     *types.Package
+		version string
+	}
+	memo := make(map[key]map[types.Object]string) // records symbol's minimum Go version
+	disallowedSymbols := func(pkg *types.Package, version string) map[types.Object]string {
+		k := key{pkg, version}
+		disallowed, ok := memo[k]
+		if !ok {
+			disallowed = typesinternal.TooNewStdSymbols(pkg, version)
+			memo[k] = disallowed
+		}
+		return disallowed
+	}
+
+	// Scan the syntax looking for references to symbols
+	// that are disallowed by the version of the file.
+	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
+	nodeFilter := []ast.Node{
+		(*ast.File)(nil),
+		(*ast.Ident)(nil),
+	}
+	var fileVersion string // "" => no check
+	inspect.Preorder(nodeFilter, func(n ast.Node) {
+		switch n := n.(type) {
+		case *ast.File:
+			if isGenerated(n) {
+				// Suppress diagnostics in generated files (such as cgo).
+				fileVersion = ""
+			} else {
+				fileVersion = versions.Lang(versions.FileVersion(pass.TypesInfo, n))
+				// (may be "" if unknown)
+			}
+
+		case *ast.Ident:
+			if fileVersion != "" {
+				if obj, ok := pass.TypesInfo.Uses[n]; ok && obj.Pkg() != nil {
+					disallowed := disallowedSymbols(obj.Pkg(), fileVersion)
+					if minVersion, ok := disallowed[origin(obj)]; ok {
+						noun := "module"
+						if fileVersion != pkgVersion {
+							noun = "file"
+						}
+						pass.ReportRangef(n, "%s.%s requires %v or later (%s is %s)",
+							obj.Pkg().Name(), obj.Name(), minVersion, noun, fileVersion)
+					}
+				}
+			}
+		}
+	})
+	return nil, nil
+}
+
+// Reduced from x/tools/gopls/internal/golang/util.go. Good enough for now.
+// TODO(adonovan): use ast.IsGenerated in go1.21.
+func isGenerated(f *ast.File) bool {
+	for _, group := range f.Comments {
+		for _, comment := range group.List {
+			if matched := generatedRx.MatchString(comment.Text); matched {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// Matches cgo generated comment as well as the proposed standard:
+//
+//	https://golang.org/s/generatedcode
+var generatedRx = regexp.MustCompile(`// .*DO NOT EDIT\.?`)
+
+// origin returns the original uninstantiated symbol for obj.
+func origin(obj types.Object) types.Object {
+	switch obj := obj.(type) {
+	case *types.Var:
+		return obj.Origin()
+	case *types.Func:
+		return obj.Origin()
+	case *types.TypeName:
+		if named, ok := obj.Type().(*types.Named); ok { // (don't unalias)
+			return named.Origin().Obj()
+		}
+	}
+	return obj
+}
+
+// TODO(adonovan): use go1.21 slices.Contains.
+func slicesContains[S ~[]E, E comparable](slice S, x E) bool {
+	for _, elem := range slice {
+		if elem == x {
+			return true
+		}
+	}
+	return false
+}

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/tests/tests.go

@@ -447,6 +447,18 @@ func checkExampleName(pass *analysis.Pass, fn *ast.FuncDecl) {
 	}
 }
 
+type tokenRange struct {
+	p, e token.Pos
+}
+
+func (r tokenRange) Pos() token.Pos {
+	return r.p
+}
+
+func (r tokenRange) End() token.Pos {
+	return r.e
+}
+
 func checkTest(pass *analysis.Pass, fn *ast.FuncDecl, prefix string) {
 	// Want functions with 0 results and 1 parameter.
 	if fn.Type.Results != nil && len(fn.Type.Results.List) > 0 ||
@@ -464,12 +476,11 @@ func checkTest(pass *analysis.Pass, fn *ast.FuncDecl, prefix string) {
 	if tparams := fn.Type.TypeParams; tparams != nil && len(tparams.List) > 0 {
 		// Note: cmd/go/internal/load also errors about TestXXX and BenchmarkXXX functions with type parameters.
 		// We have currently decided to also warn before compilation/package loading. This can help users in IDEs.
-		// TODO(adonovan): use ReportRangef(tparams).
-		pass.Reportf(fn.Pos(), "%s has type parameters: it will not be run by go test as a %sXXX function", fn.Name.Name, prefix)
+		at := tokenRange{tparams.Opening, tparams.Closing}
+		pass.ReportRangef(at, "%s has type parameters: it will not be run by go test as a %sXXX function", fn.Name.Name, prefix)
 	}
 
 	if !isTestSuffix(fn.Name.Name[len(prefix):]) {
-		// TODO(adonovan): use ReportRangef(fn.Name).
-		pass.Reportf(fn.Pos(), "%s has malformed name: first letter after '%s' must not be lowercase", fn.Name.Name, prefix)
+		pass.ReportRangef(fn.Name, "%s has malformed name: first letter after '%s' must not be lowercase", fn.Name.Name, prefix)
 	}
 }

src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go

@@ -49,6 +49,7 @@ import (
 
 	"golang.org/x/tools/go/analysis"
 	"golang.org/x/tools/go/analysis/internal/analysisflags"
+	"golang.org/x/tools/internal/analysisinternal"
 	"golang.org/x/tools/internal/facts"
 	"golang.org/x/tools/internal/versions"
 )
@@ -377,6 +378,7 @@ func run(fset *token.FileSet, cfg *Config, analyzers []*analysis.Analyzer) ([]re
 				ExportPackageFact: facts.ExportPackageFact,
 				AllPackageFacts:   func() []analysis.PackageFact { return facts.AllPackageFacts(factFilter) },
 			}
+			pass.ReadFile = analysisinternal.MakeReadFile(pass)
 
 			t0 := time.Now()
 			act.result, act.err = a.Run(pass)

src/cmd/vendor/golang.org/x/tools/go/types/typeutil/map.go

@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // Package typeutil defines various utilities for types, such as Map,
-// a mapping from types.Type to interface{} values.
+// a mapping from types.Type to any values.
 package typeutil // import "golang.org/x/tools/go/types/typeutil"
 
 import (
@@ -17,7 +17,7 @@ import (
 )
 
 // Map is a hash-table-based mapping from types (types.Type) to
-// arbitrary interface{} values.  The concrete types that implement
+// arbitrary any values.  The concrete types that implement
 // the Type interface are pointers.  Since they are not canonicalized,
 // == cannot be used to check for equivalence, and thus we cannot
 // simply use a Go map.
@@ -34,7 +34,7 @@ type Map struct {
 // entry is an entry (key/value association) in a hash bucket.
 type entry struct {
 	key   types.Type
-	value interface{}
+	value any
 }
 
 // SetHasher sets the hasher used by Map.
@@ -82,7 +82,7 @@ func (m *Map) Delete(key types.Type) bool {
 
 // At returns the map entry for the given key.
 // The result is nil if the entry is not present.
-func (m *Map) At(key types.Type) interface{} {
+func (m *Map) At(key types.Type) any {
 	if m != nil && m.table != nil {
 		for _, e := range m.table[m.hasher.Hash(key)] {
 			if e.key != nil && types.Identical(key, e.key) {
@@ -95,7 +95,7 @@ func (m *Map) At(key types.Type) interface{} {
 
 // Set sets the map entry for key to val,
 // and returns the previous entry, if any.
-func (m *Map) Set(key types.Type, value interface{}) (prev interface{}) {
+func (m *Map) Set(key types.Type, value any) (prev any) {
 	if m.table != nil {
 		hash := m.hasher.Hash(key)
 		bucket := m.table[hash]
@@ -142,7 +142,7 @@ func (m *Map) Len() int {
 // f will not be invoked for it, but if f inserts a map entry that
 // Iterate has not yet reached, whether or not f will be invoked for
 // it is unspecified.
-func (m *Map) Iterate(f func(key types.Type, value interface{})) {
+func (m *Map) Iterate(f func(key types.Type, value any)) {
 	if m != nil {
 		for _, bucket := range m.table {
 			for _, e := range bucket {
@@ -158,7 +158,7 @@ func (m *Map) Iterate(f func(key types.Type, value interface{})) {
 // The order is unspecified.
 func (m *Map) Keys() []types.Type {
 	keys := make([]types.Type, 0, m.Len())
-	m.Iterate(func(key types.Type, _ interface{}) {
+	m.Iterate(func(key types.Type, _ any) {
 		keys = append(keys, key)
 	})
 	return keys
@@ -171,7 +171,7 @@ func (m *Map) toString(values bool) string {
 	var buf bytes.Buffer
 	fmt.Fprint(&buf, "{")
 	sep := ""
-	m.Iterate(func(key types.Type, value interface{}) {
+	m.Iterate(func(key types.Type, value any) {
 		fmt.Fprint(&buf, sep)
 		sep = ", "
 		fmt.Fprint(&buf, key)
@@ -209,7 +209,7 @@ type Hasher struct {
 	memo map[types.Type]uint32
 
 	// ptrMap records pointer identity.
-	ptrMap map[interface{}]uint32
+	ptrMap map[any]uint32
 
 	// sigTParams holds type parameters from the signature being hashed.
 	// Signatures are considered identical modulo renaming of type parameters, so
@@ -227,7 +227,7 @@ type Hasher struct {
 func MakeHasher() Hasher {
 	return Hasher{
 		memo:       make(map[types.Type]uint32),
-		ptrMap:     make(map[interface{}]uint32),
+		ptrMap:     make(map[any]uint32),
 		sigTParams: nil,
 	}
 }
@@ -261,7 +261,7 @@ func (h Hasher) hashFor(t types.Type) uint32 {
 		return uint32(t.Kind())
 
 	case *aliases.Alias:
-		return h.Hash(t.Underlying())
+		return h.Hash(aliases.Unalias(t))
 
 	case *types.Array:
 		return 9043 + 2*uint32(t.Len()) + 3*h.Hash(t.Elem())
@@ -432,7 +432,7 @@ func (h Hasher) hashTypeParam(t *types.TypeParam) uint32 {
 
 // hashPtr hashes the pointer identity of ptr. It uses h.ptrMap to ensure that
 // pointers values are not dependent on the GC.
-func (h Hasher) hashPtr(ptr interface{}) uint32 {
+func (h Hasher) hashPtr(ptr any) uint32 {
 	if hash, ok := h.ptrMap[ptr]; ok {
 		return hash
 	}
@@ -462,7 +462,7 @@ func (h Hasher) shallowHash(t types.Type) uint32 {
 	// so there's no need to optimize anything else.
 	switch t := t.(type) {
 	case *aliases.Alias:
-		return h.shallowHash(t.Underlying())
+		return h.shallowHash(aliases.Unalias(t))
 
 	case *types.Signature:
 		var hash uint32 = 604171

src/cmd/vendor/golang.org/x/tools/internal/aliases/aliases.go

@@ -16,10 +16,14 @@ import (
 // NewAlias creates a new TypeName in Package pkg that
 // is an alias for the type rhs.
 //
-// When GoVersion>=1.22 and GODEBUG=gotypesalias=1,
-// the Type() of the return value is a *types.Alias.
-func NewAlias(pos token.Pos, pkg *types.Package, name string, rhs types.Type) *types.TypeName {
-	if enabled() {
+// The enabled parameter determines whether the resulting [TypeName]'s
+// type is an [types.Alias]. Its value must be the result of a call to
+// [Enabled], which computes the effective value of
+// GODEBUG=gotypesalias=... by invoking the type checker. The Enabled
+// function is expensive and should be called once per task (e.g.
+// package import), not once per call to NewAlias.
+func NewAlias(enabled bool, pos token.Pos, pkg *types.Package, name string, rhs types.Type) *types.TypeName {
+	if enabled {
 		tname := types.NewTypeName(pos, pkg, name, nil)
 		newAlias(tname, rhs)
 		return tname

src/cmd/vendor/golang.org/x/tools/internal/aliases/aliases_go121.go

@@ -15,16 +15,17 @@ import (
 // It will never be created by go/types.
 type Alias struct{}
 
-func (*Alias) String() string { panic("unreachable") }
-
+func (*Alias) String() string         { panic("unreachable") }
 func (*Alias) Underlying() types.Type { panic("unreachable") }
-
-func (*Alias) Obj() *types.TypeName { panic("unreachable") }
+func (*Alias) Obj() *types.TypeName   { panic("unreachable") }
+func Rhs(alias *Alias) types.Type     { panic("unreachable") }
 
 // Unalias returns the type t for go <=1.21.
 func Unalias(t types.Type) types.Type { return t }
 
-// Always false for go <=1.21. Ignores GODEBUG.
-func enabled() bool { return false }
-
 func newAlias(name *types.TypeName, rhs types.Type) *Alias { panic("unreachable") }
+
+// Enabled reports whether [NewAlias] should create [types.Alias] types.
+//
+// Before go1.22, this function always returns false.
+func Enabled() bool { return false }

src/cmd/vendor/golang.org/x/tools/internal/aliases/aliases_go122.go

@@ -12,14 +12,22 @@ import (
 	"go/parser"
 	"go/token"
 	"go/types"
-	"os"
-	"strings"
-	"sync"
 )
 
 // Alias is an alias of types.Alias.
 type Alias = types.Alias
 
+// Rhs returns the type on the right-hand side of the alias declaration.
+func Rhs(alias *Alias) types.Type {
+	if alias, ok := any(alias).(interface{ Rhs() types.Type }); ok {
+		return alias.Rhs() // go1.23+
+	}
+
+	// go1.22's Alias didn't have the Rhs method,
+	// so Unalias is the best we can do.
+	return Unalias(alias)
+}
+
 // Unalias is a wrapper of types.Unalias.
 func Unalias(t types.Type) types.Type { return types.Unalias(t) }
 
@@ -33,40 +41,23 @@ func newAlias(tname *types.TypeName, rhs types.Type) *Alias {
 	return a
 }
 
-// enabled returns true when types.Aliases are enabled.
-func enabled() bool {
-	// Use the gotypesalias value in GODEBUG if set.
-	godebug := os.Getenv("GODEBUG")
-	value := -1 // last set value.
-	for _, f := range strings.Split(godebug, ",") {
-		switch f {
-		case "gotypesalias=1":
-			value = 1
-		case "gotypesalias=0":
-			value = 0
-		}
-	}
-	switch value {
-	case 0:
-		return false
-	case 1:
-		return true
-	default:
-		return aliasesDefault()
-	}
+// Enabled reports whether [NewAlias] should create [types.Alias] types.
+//
+// This function is expensive! Call it sparingly.
+func Enabled() bool {
+	// The only reliable way to compute the answer is to invoke go/types.
+	// We don't parse the GODEBUG environment variable, because
+	// (a) it's tricky to do so in a manner that is consistent
+	//     with the godebug package; in particular, a simple
+	//     substring check is not good enough. The value is a
+	//     rightmost-wins list of options. But more importantly:
+	// (b) it is impossible to detect changes to the effective
+	//     setting caused by os.Setenv("GODEBUG"), as happens in
+	//     many tests. Therefore any attempt to cache the result
+	//     is just incorrect.
+	fset := token.NewFileSet()
+	f, _ := parser.ParseFile(fset, "a.go", "package p; type A = int", 0)
+	pkg, _ := new(types.Config).Check("p", fset, []*ast.File{f}, nil)
+	_, enabled := pkg.Scope().Lookup("A").Type().(*types.Alias)
+	return enabled
 }
-
-// aliasesDefault reports if aliases are enabled by default.
-func aliasesDefault() bool {
-	// Dynamically check if Aliases will be produced from go/types.
-	aliasesDefaultOnce.Do(func() {
-		fset := token.NewFileSet()
-		f, _ := parser.ParseFile(fset, "a.go", "package p; type A = int", 0)
-		pkg, _ := new(types.Config).Check("p", fset, []*ast.File{f}, nil)
-		_, gotypesaliasDefault = pkg.Scope().Lookup("A").Type().(*types.Alias)
-	})
-	return gotypesaliasDefault
-}
-
-var gotypesaliasDefault bool
-var aliasesDefaultOnce sync.Once

src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/analysis.go

@@ -12,8 +12,10 @@ import (
 	"go/ast"
 	"go/token"
 	"go/types"
+	"os"
 	"strconv"
 
+	"golang.org/x/tools/go/analysis"
 	"golang.org/x/tools/internal/aliases"
 )
 
@@ -32,22 +34,22 @@ func TypeErrorEndPos(fset *token.FileSet, src []byte, start token.Pos) token.Pos
 func ZeroValue(f *ast.File, pkg *types.Package, typ types.Type) ast.Expr {
 	// TODO(adonovan): think about generics, and also generic aliases.
 	under := aliases.Unalias(typ)
-	// Don't call Underlying unconditionally: although it removed
+	// Don't call Underlying unconditionally: although it removes
 	// Named and Alias, it also removes TypeParam.
-	if n, ok := typ.(*types.Named); ok {
+	if n, ok := under.(*types.Named); ok {
 		under = n.Underlying()
 	}
-	switch u := under.(type) {
+	switch under := under.(type) {
 	case *types.Basic:
 		switch {
-		case u.Info()&types.IsNumeric != 0:
+		case under.Info()&types.IsNumeric != 0:
 			return &ast.BasicLit{Kind: token.INT, Value: "0"}
-		case u.Info()&types.IsBoolean != 0:
+		case under.Info()&types.IsBoolean != 0:
 			return &ast.Ident{Name: "false"}
-		case u.Info()&types.IsString != 0:
+		case under.Info()&types.IsString != 0:
 			return &ast.BasicLit{Kind: token.STRING, Value: `""`}
 		default:
-			panic(fmt.Sprintf("unknown basic type %v", u))
+			panic(fmt.Sprintf("unknown basic type %v", under))
 		}
 	case *types.Chan, *types.Interface, *types.Map, *types.Pointer, *types.Signature, *types.Slice, *types.Array:
 		return ast.NewIdent("nil")
@@ -178,7 +180,7 @@ func TypeExpr(f *ast.File, pkg *types.Package, typ types.Type) ast.Expr {
 				List: returns,
 			},
 		}
-	case *types.Named:
+	case interface{ Obj() *types.TypeName }: // *types.{Alias,Named,TypeParam}
 		if t.Obj().Pkg() == nil {
 			return ast.NewIdent(t.Obj().Name())
 		}
@@ -393,3 +395,38 @@ func equivalentTypes(want, got types.Type) bool {
 	}
 	return types.AssignableTo(want, got)
 }
+
+// MakeReadFile returns a simple implementation of the Pass.ReadFile function.
+func MakeReadFile(pass *analysis.Pass) func(filename string) ([]byte, error) {
+	return func(filename string) ([]byte, error) {
+		if err := checkReadable(pass, filename); err != nil {
+			return nil, err
+		}
+		return os.ReadFile(filename)
+	}
+}
+
+// checkReadable enforces the access policy defined by the ReadFile field of [analysis.Pass].
+func checkReadable(pass *analysis.Pass, filename string) error {
+	if slicesContains(pass.OtherFiles, filename) ||
+		slicesContains(pass.IgnoredFiles, filename) {
+		return nil
+	}
+	for _, f := range pass.Files {
+		// TODO(adonovan): use go1.20 f.FileStart
+		if pass.Fset.File(f.Pos()).Name() == filename {
+			return nil
+		}
+	}
+	return fmt.Errorf("Pass.ReadFile: %s is not among OtherFiles, IgnoredFiles, or names of Files", filename)
+}
+
+// TODO(adonovan): use go1.21 slices.Contains.
+func slicesContains[S ~[]E, E comparable](slice S, x E) bool {
+	for _, elem := range slice {
+		if elem == x {
+			return true
+		}
+	}
+	return false
+}

src/cmd/vendor/golang.org/x/tools/internal/facts/facts.go

@@ -295,10 +295,10 @@ func (s *Set) Encode() []byte {
 		// we aren't careful about which structs or methods
 		// we rexport: it should be only those referenced
 		// from the API of s.pkg.
-		// TOOD(adonovan): opt: be more precise. e.g.
+		// TODO(adonovan): opt: be more precise. e.g.
 		// intersect with the set of objects computed by
 		// importMap(s.pkg.Imports()).
-		// TOOD(adonovan): opt: implement "shallow" facts.
+		// TODO(adonovan): opt: implement "shallow" facts.
 		if k.pkg != s.pkg {
 			if k.obj == nil {
 				continue // imported package fact

src/cmd/vendor/golang.org/x/tools/internal/typeparams/common.go

@@ -73,7 +73,7 @@ func IsTypeParam(t types.Type) bool {
 // implements the following rule for uninstantiated generic types:
 //
 // If V and T are generic named types, then V is considered assignable to T if,
-// for every possible instantation of V[A_1, ..., A_N], the instantiation
+// for every possible instantiation of V[A_1, ..., A_N], the instantiation
 // T[A_1, ..., A_N] is valid and V[A_1, ..., A_N] implements T[A_1, ..., A_N].
 //
 // If T has structural constraints, they must be satisfied by V.

src/cmd/vendor/golang.org/x/tools/internal/typesinternal/errorcode.go

@@ -1449,10 +1449,10 @@ const (
 	NotAGenericType
 
 	// WrongTypeArgCount occurs when a type or function is instantiated with an
-	// incorrent number of type arguments, including when a generic type or
+	// incorrect number of type arguments, including when a generic type or
 	// function is used without instantiation.
 	//
-	// Errors inolving failed type inference are assigned other error codes.
+	// Errors involving failed type inference are assigned other error codes.
 	//
 	// Example:
 	//  type T[p any] int

src/cmd/vendor/modules.txt

@@ -25,7 +25,7 @@ golang.org/x/arch/x86/x86asm
 # golang.org/x/build v0.0.0-20240222153247-cf4ed81bb19f
 ## explicit; go 1.21
 golang.org/x/build/relnote
-# golang.org/x/mod v0.16.0
+# golang.org/x/mod v0.17.0
 ## explicit; go 1.18
 golang.org/x/mod/internal/lazyregexp
 golang.org/x/mod/modfile
@@ -36,7 +36,7 @@ golang.org/x/mod/sumdb/dirhash
 golang.org/x/mod/sumdb/note
 golang.org/x/mod/sumdb/tlog
 golang.org/x/mod/zip
-# golang.org/x/sync v0.6.0
+# golang.org/x/sync v0.7.0
 ## explicit; go 1.18
 golang.org/x/sync/errgroup
 golang.org/x/sync/semaphore
@@ -71,7 +71,7 @@ golang.org/x/text/internal/tag
 golang.org/x/text/language
 golang.org/x/text/transform
 golang.org/x/text/unicode/norm
-# golang.org/x/tools v0.19.1-0.20240329171618-904c6baa6e14
+# golang.org/x/tools v0.20.1-0.20240429173604-74c9cfe4d22f
 ## explicit; go 1.19
 golang.org/x/tools/cmd/bisect
 golang.org/x/tools/cover
@@ -103,6 +103,7 @@ golang.org/x/tools/go/analysis/passes/shift
 golang.org/x/tools/go/analysis/passes/sigchanyzer
 golang.org/x/tools/go/analysis/passes/slog
 golang.org/x/tools/go/analysis/passes/stdmethods
+golang.org/x/tools/go/analysis/passes/stdversion
 golang.org/x/tools/go/analysis/passes/stringintconv
 golang.org/x/tools/go/analysis/passes/structtag
 golang.org/x/tools/go/analysis/passes/testinggoroutine