diff --git a/src/cmd/go.mod b/src/cmd/go.mod
index e6431c0f20a..c72a250aeab 100644
--- a/src/cmd/go.mod
+++ b/src/cmd/go.mod
@@ -11,7 +11,7 @@ require (
 	golang.org/x/sys v0.36.0
 	golang.org/x/telemetry v0.0.0-20250908211612-aef8a434d053
 	golang.org/x/term v0.34.0
-	golang.org/x/tools v0.37.1-0.20250911182313-3adf0e96d87d
+	golang.org/x/tools v0.37.1-0.20250915202913-9fccddc465ef
 )
 
 require (
diff --git a/src/cmd/go.sum b/src/cmd/go.sum
index 5a70558fe9c..a4801f18430 100644
--- a/src/cmd/go.sum
+++ b/src/cmd/go.sum
@@ -22,7 +22,7 @@ golang.org/x/term v0.34.0 h1:O/2T7POpk0ZZ7MAzMeWFSg6S5IpWd/RXDlM9hgM3DR4=
 golang.org/x/term v0.34.0/go.mod h1:5jC53AEywhIVebHgPVeg0mj8OD3VO9OzclacVrqpaAw=
 golang.org/x/text v0.29.0 h1:1neNs90w9YzJ9BocxfsQNHKuAT4pkghyXc4nhZ6sJvk=
 golang.org/x/text v0.29.0/go.mod h1:7MhJOA9CD2qZyOKYazxdYMF85OwPdEr9jTtBpO7ydH4=
-golang.org/x/tools v0.37.1-0.20250911182313-3adf0e96d87d h1:ykSs3aFXygx903AtF0IG27E/xLaCW5t85BAdCALyp8s=
-golang.org/x/tools v0.37.1-0.20250911182313-3adf0e96d87d/go.mod h1:MBN5QPQtLMHVdvsbtarmTNukZDdgwdwlO5qGacAzF0w=
+golang.org/x/tools v0.37.1-0.20250915202913-9fccddc465ef h1:ISPkUgvOYIt0oS7oVnwAPktCKBvgWkDlWWGMgX0veZM=
+golang.org/x/tools v0.37.1-0.20250915202913-9fccddc465ef/go.mod h1:MBN5QPQtLMHVdvsbtarmTNukZDdgwdwlO5qGacAzF0w=
 rsc.io/markdown v0.0.0-20240306144322-0bf8f97ee8ef h1:mqLYrXCXYEZOop9/Dbo6RPX11539nwiCNBb1icVPmw8=
 rsc.io/markdown v0.0.0-20240306144322-0bf8f97ee8ef/go.mod h1:8xcPgWmwlZONN1D9bjxtHEjrUtSEa3fakVF8iaewYKQ=
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go
index 1aa7afb9c2a..efbf05d596a 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go
@@ -237,7 +237,7 @@ Files:
 					// so accumulate them all and then prefer the one that
 					// matches build.Default.GOARCH.
 					var archCandidates []*asmArch
-					for _, fld := range strings.Fields(m[1]) {
+					for fld := range strings.FieldsSeq(m[1]) {
 						for _, a := range arches {
 							if a.name == fld {
 								archCandidates = append(archCandidates, a)
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/buildtag/buildtag.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/buildtag/buildtag.go
index 6c7a0df585d..6e32f298dc2 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/buildtag/buildtag.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/buildtag/buildtag.go
@@ -298,7 +298,7 @@ func (check *checker) plusBuildLine(pos token.Pos, line string) {
 	fields := strings.Fields(line[len("//"):])
 	// IsPlusBuildConstraint check above implies fields[0] == "+build"
 	for _, arg := range fields[1:] {
-		for _, elem := range strings.Split(arg, ",") {
+		for elem := range strings.SplitSeq(arg, ",") {
 			if strings.HasPrefix(elem, "!!") {
 				check.pass.Reportf(pos, "invalid double negative in build constraint: %s", arg)
 				check.crossCheck = false
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/hostport/hostport.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/hostport/hostport.go
index e808b1aa1ba..07f154963e8 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/hostport/hostport.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/hostport/hostport.go
@@ -10,7 +10,9 @@ import (
 	"fmt"
 	"go/ast"
 	"go/constant"
+	"go/token"
 	"go/types"
+	"strconv"
 
 	"golang.org/x/tools/go/analysis"
 	"golang.org/x/tools/go/analysis/passes/inspect"
@@ -57,13 +59,16 @@ func run(pass *analysis.Pass) (any, error) {
 	}
 
 	// checkAddr reports a diagnostic (and returns true) if e
-	// is a call of the form fmt.Sprintf("%d:%d", ...).
+	// is a call of the form fmt.Sprintf("%s:%d", ...).
 	// The diagnostic includes a fix.
 	//
 	// dialCall is non-nil if the Dial call is non-local
 	// but within the same file.
 	checkAddr := func(e ast.Expr, dialCall *ast.CallExpr) {
-		if call, ok := e.(*ast.CallExpr); ok && typeutil.Callee(info, call) == fmtSprintf {
+		if call, ok := e.(*ast.CallExpr); ok &&
+			len(call.Args) == 3 &&
+			typeutil.Callee(info, call) == fmtSprintf {
+
 			// Examine format string.
 			formatArg := call.Args[0]
 			if tv := info.Types[formatArg]; tv.Value != nil {
@@ -99,21 +104,41 @@ func run(pass *analysis.Pass) (any, error) {
 
 				// Turn numeric port into a string.
 				if numericPort {
-					//  port => fmt.Sprintf("%d", port)
-					//   123 => "123"
 					port := call.Args[2]
-					newPort := fmt.Sprintf(`fmt.Sprintf("%%d", %s)`, port)
-					if port := info.Types[port].Value; port != nil {
-						if i, ok := constant.Int64Val(port); ok {
-							newPort = fmt.Sprintf(`"%d"`, i) // numeric constant
+
+					// Is port an integer literal?
+					//
+					// (Don't allow arbitrary constants k otherwise the
+					// transformation k => fmt.Sprintf("%d", "123")
+					// loses the symbolic connection to k.)
+					var kPort int64 = -1
+					if lit, ok := port.(*ast.BasicLit); ok && lit.Kind == token.INT {
+						if v, err := strconv.ParseInt(lit.Value, 0, 64); err == nil {
+							kPort = v
 						}
 					}
-
-					edits = append(edits, analysis.TextEdit{
-						Pos:     port.Pos(),
-						End:     port.End(),
-						NewText: []byte(newPort),
-					})
+					if kPort >= 0 {
+						// literal: 0x7B  => "123"
+						edits = append(edits, analysis.TextEdit{
+							Pos:     port.Pos(),
+							End:     port.End(),
+							NewText: fmt.Appendf(nil, `"%d"`, kPort), // (decimal)
+						})
+					} else {
+						// non-literal: port => fmt.Sprintf("%d", port)
+						edits = append(edits, []analysis.TextEdit{
+							{
+								Pos:     port.Pos(),
+								End:     port.Pos(),
+								NewText: []byte(`fmt.Sprintf("%d", `),
+							},
+							{
+								Pos:     port.End(),
+								End:     port.End(),
+								NewText: []byte(`)`),
+							},
+						}...)
+					}
 				}
 
 				// Refer to Dial call, if not adjacent.
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go
index 9ad18a041e5..f008eca36fe 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go
@@ -992,7 +992,7 @@ func (ss stringSet) String() string {
 }
 
 func (ss stringSet) Set(flag string) error {
-	for _, name := range strings.Split(flag, ",") {
+	for name := range strings.SplitSeq(flag, ",") {
 		if len(name) == 0 {
 			return fmt.Errorf("empty string")
 		}
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/unusedresult/unusedresult.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/unusedresult/unusedresult.go
index 556ffed7d99..ed4cf7ae0be 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/unusedresult/unusedresult.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/unusedresult/unusedresult.go
@@ -188,7 +188,7 @@ func (ss *stringSetFlag) String() string {
 func (ss *stringSetFlag) Set(s string) error {
 	m := make(map[string]bool) // clobber previous value
 	if s != "" {
-		for _, name := range strings.Split(s, ",") {
+		for name := range strings.SplitSeq(s, ",") {
 			if name == "" {
 				continue // TODO: report error? proceed?
 			}
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go
index 633af5a1da0..7b805b882bf 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go
@@ -74,7 +74,8 @@ type Config struct {
 	VetxOnly                  bool              // run analysis only for facts, not diagnostics
 	VetxOutput                string            // where to write file of fact information
 	Stdout                    string            // write stdout (e.g. JSON, unified diff) to this file
-	SucceedOnTypecheckFailure bool
+	SucceedOnTypecheckFailure bool              // obsolete awful hack; see #18395 and below
+	WarnDiagnostics           bool              // printing diagnostics should not cause a non-zero exit
 }
 
 // Main is the main function of a vet-like analysis tool that must be
@@ -162,7 +163,7 @@ func Run(configFile string, analyzers []*analysis.Analyzer) {
 
 	// In VetxOnly mode, the analysis is run only for facts.
 	if !cfg.VetxOnly {
-		code = processResults(fset, cfg.ID, results)
+		code = processResults(fset, cfg.ID, results, cfg.WarnDiagnostics)
 	}
 
 	os.Exit(code)
@@ -186,7 +187,7 @@ func readConfig(filename string) (*Config, error) {
 	return cfg, nil
 }
 
-func processResults(fset *token.FileSet, id string, results []result) (exit int) {
+func processResults(fset *token.FileSet, id string, results []result, warnDiagnostics bool) (exit int) {
 	if analysisflags.Fix {
 		// Don't print the diagnostics,
 		// but apply all fixes from the root actions.
@@ -235,7 +236,9 @@ func processResults(fset *token.FileSet, id string, results []result) (exit int)
 		for _, res := range results {
 			for _, diag := range res.diagnostics {
 				analysisflags.PrintPlain(os.Stderr, fset, analysisflags.Context, diag)
-				exit = 1
+				if !warnDiagnostics {
+					exit = 1
+				}
 			}
 		}
 	}
diff --git a/src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/analysis.go b/src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/analysis.go
index c8e349f4fed..bc7f9984e90 100644
--- a/src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/analysis.go
+++ b/src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/analysis.go
@@ -74,25 +74,6 @@ func TypeErrorEndPos(fset *token.FileSet, src []byte, start token.Pos) token.Pos
 	return end
 }
 
-// WalkASTWithParent walks the AST rooted at n. The semantics are
-// similar to ast.Inspect except it does not call f(nil).
-func WalkASTWithParent(n ast.Node, f func(n ast.Node, parent ast.Node) bool) {
-	var ancestors []ast.Node
-	ast.Inspect(n, func(n ast.Node) (recurse bool) {
-		if n == nil {
-			ancestors = ancestors[:len(ancestors)-1]
-			return false
-		}
-
-		var parent ast.Node
-		if len(ancestors) > 0 {
-			parent = ancestors[len(ancestors)-1]
-		}
-		ancestors = append(ancestors, n)
-		return f(n, parent)
-	})
-}
-
 // MatchingIdents finds the names of all identifiers in 'node' that match any of the given types.
 // 'pos' represents the position at which the identifiers may be inserted. 'pos' must be within
 // the scope of each of identifier we select. Otherwise, we will insert a variable at 'pos' that
diff --git a/src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/extractdoc.go b/src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/extractdoc.go
index 39507723d3d..bfb5900f1b3 100644
--- a/src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/extractdoc.go
+++ b/src/cmd/vendor/golang.org/x/tools/internal/analysisinternal/extractdoc.go
@@ -97,7 +97,7 @@ func ExtractDoc(content, name string) (string, error) {
 	if f.Doc == nil {
 		return "", fmt.Errorf("Go source file has no package doc comment")
 	}
-	for _, section := range strings.Split(f.Doc.Text(), "\n# ") {
+	for section := range strings.SplitSeq(f.Doc.Text(), "\n# ") {
 		if body := strings.TrimPrefix(section, "Analyzer "+name); body != section &&
 			body != "" &&
 			body[0] == '\r' || body[0] == '\n' {
diff --git a/src/cmd/vendor/golang.org/x/tools/internal/astutil/comment.go b/src/cmd/vendor/golang.org/x/tools/internal/astutil/comment.go
index ee4be23f226..c3a256c987c 100644
--- a/src/cmd/vendor/golang.org/x/tools/internal/astutil/comment.go
+++ b/src/cmd/vendor/golang.org/x/tools/internal/astutil/comment.go
@@ -15,7 +15,7 @@ import (
 // https://go.dev/wiki/Deprecated, or "" if the documented symbol is not
 // deprecated.
 func Deprecation(doc *ast.CommentGroup) string {
-	for _, p := range strings.Split(doc.Text(), "\n\n") {
+	for p := range strings.SplitSeq(doc.Text(), "\n\n") {
 		// There is still some ambiguity for deprecation message. This function
 		// only returns the paragraph introduced by "Deprecated: ". More
 		// information related to the deprecation may follow in additional
diff --git a/src/cmd/vendor/golang.org/x/tools/internal/typesinternal/qualifier.go b/src/cmd/vendor/golang.org/x/tools/internal/typesinternal/qualifier.go
index b64f714eb30..64f47919f02 100644
--- a/src/cmd/vendor/golang.org/x/tools/internal/typesinternal/qualifier.go
+++ b/src/cmd/vendor/golang.org/x/tools/internal/typesinternal/qualifier.go
@@ -15,6 +15,14 @@ import (
 // file.
 // If the same package is imported multiple times, the last appearance is
 // recorded.
+//
+// TODO(adonovan): this function ignores the effect of shadowing. It
+// should accept a [token.Pos] and a [types.Info] and compute only the
+// set of imports that are not shadowed at that point, analogous to
+// [analysisinternal.AddImport]. It could also compute (as a side
+// effect) the set of additional imports required to ensure that there
+// is an accessible import for each necessary package, making it
+// converge even more closely with AddImport.
 func FileQualifier(f *ast.File, pkg *types.Package) types.Qualifier {
 	// Construct mapping of import paths to their defined names.
 	// It is only necessary to look at renaming imports.
diff --git a/src/cmd/vendor/modules.txt b/src/cmd/vendor/modules.txt
index 37cd448bc9e..f166b77ea20 100644
--- a/src/cmd/vendor/modules.txt
+++ b/src/cmd/vendor/modules.txt
@@ -73,7 +73,7 @@ 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 v0.37.1-0.20250911182313-3adf0e96d87d
+# golang.org/x/tools v0.37.1-0.20250915202913-9fccddc465ef
 ## explicit; go 1.24.0
 golang.org/x/tools/cmd/bisect
 golang.org/x/tools/cover