Update deps, especially quic-go

vendor/golang.org/x/tools/go/ast/astutil/enclosing.go

@@ -106,8 +106,21 @@ func PathEnclosingInterval(root *ast.File, start, end token.Pos) (path []ast.Nod
 
 			// Does augmented child strictly contain [start, end)?
 			if augPos <= start && end <= augEnd {
-				_, isToken := child.(tokenNode)
-				return isToken || visit(child)
+				if is[tokenNode](child) {
+					return true
+				}
+
+				// childrenOf elides the FuncType node beneath FuncDecl.
+				// Add it back here for TypeParams, Params, Results,
+				// all FieldLists). But we don't add it back for the "func" token
+				// even though it is is the tree at FuncDecl.Type.Func.
+				if decl, ok := node.(*ast.FuncDecl); ok {
+					if fields, ok := child.(*ast.FieldList); ok && fields != decl.Recv {
+						path = append(path, decl.Type)
+					}
+				}
+
+				return visit(child)
 			}
 
 			// Does [start, end) overlap multiple children?
@@ -313,6 +326,8 @@ func childrenOf(n ast.Node) []ast.Node {
 		//
 		// As a workaround, we inline the case for FuncType
 		// here and order things correctly.
+		// We also need to insert the elided FuncType just
+		// before the 'visit' recursion.
 		//
 		children = nil // discard ast.Walk(FuncDecl) info subtrees
 		children = append(children, tok(n.Type.Func, len("func")))
@@ -632,3 +647,8 @@ func NodeDescription(n ast.Node) string {
 	}
 	panic(fmt.Sprintf("unexpected node type: %T", n))
 }
+
+func is[T any](x any) bool {
+	_, ok := x.(T)
+	return ok
+}

vendor/golang.org/x/tools/go/ast/astutil/imports.go

@@ -344,7 +344,12 @@ func RewriteImport(fset *token.FileSet, f *ast.File, oldPath, newPath string) (r
 }
 
 // UsesImport reports whether a given import is used.
+// The provided File must have been parsed with syntactic object resolution
+// (not using go/parser.SkipObjectResolution).
 func UsesImport(f *ast.File, path string) (used bool) {
+	if f.Scope == nil {
+		panic("file f was not parsed with syntactic object resolution")
+	}
 	spec := importSpec(f, path)
 	if spec == nil {
 		return

vendor/golang.org/x/tools/go/ast/astutil/util.go

@@ -7,12 +7,5 @@ package astutil
 import "go/ast"
 
 // Unparen returns e with any enclosing parentheses stripped.
-func Unparen(e ast.Expr) ast.Expr {
-	for {
-		p, ok := e.(*ast.ParenExpr)
-		if !ok {
-			return e
-		}
-		e = p.X
-	}
-}
+// Deprecated: use [ast.Unparen].
+func Unparen(e ast.Expr) ast.Expr { return ast.Unparen(e) }

vendor/golang.org/x/tools/go/ast/inspector/inspector.go

@@ -36,6 +36,9 @@ package inspector
 
 import (
 	"go/ast"
+	_ "unsafe"
+
+	"golang.org/x/tools/internal/astutil/edge"
 )
 
 // An Inspector provides methods for inspecting
@@ -44,6 +47,24 @@ type Inspector struct {
 	events []event
 }
 
+//go:linkname events
+func events(in *Inspector) []event { return in.events }
+
+func packEdgeKindAndIndex(ek edge.Kind, index int) int32 {
+	return int32(uint32(index+1)<<7 | uint32(ek))
+}
+
+// unpackEdgeKindAndIndex unpacks the edge kind and edge index (within
+// an []ast.Node slice) from the parent field of a pop event.
+//
+//go:linkname unpackEdgeKindAndIndex
+func unpackEdgeKindAndIndex(x int32) (edge.Kind, int) {
+	// The "parent" field of a pop node holds the
+	// edge Kind in the lower 7 bits and the index+1
+	// in the upper 25.
+	return edge.Kind(x & 0x7f), int(x>>7) - 1
+}
+
 // New returns an Inspector for the specified syntax trees.
 func New(files []*ast.File) *Inspector {
 	return &Inspector{traverse(files)}
@@ -52,9 +73,10 @@ func New(files []*ast.File) *Inspector {
 // An event represents a push or a pop
 // of an ast.Node during a traversal.
 type event struct {
-	node  ast.Node
-	typ   uint64 // typeOf(node) on push event, or union of typ strictly between push and pop events on pop events
-	index int    // index of corresponding push or pop event
+	node   ast.Node
+	typ    uint64 // typeOf(node) on push event, or union of typ strictly between push and pop events on pop events
+	index  int32  // index of corresponding push or pop event
+	parent int32  // index of parent's push node (push nodes only), or packed edge kind/index (pop nodes only)
 }
 
 // TODO: Experiment with storing only the second word of event.node (unsafe.Pointer).
@@ -73,8 +95,17 @@ func (in *Inspector) Preorder(types []ast.Node, f func(ast.Node)) {
 	// check, Preorder is almost twice as fast as Nodes. The two
 	// features seem to contribute similar slowdowns (~1.4x each).
 
+	// This function is equivalent to the PreorderSeq call below,
+	// but to avoid the additional dynamic call (which adds 13-35%
+	// to the benchmarks), we expand it out.
+	//
+	// in.PreorderSeq(types...)(func(n ast.Node) bool {
+	// 	f(n)
+	// 	return true
+	// })
+
 	mask := maskOf(types)
-	for i := 0; i < len(in.events); {
+	for i := int32(0); i < int32(len(in.events)); {
 		ev := in.events[i]
 		if ev.index > i {
 			// push
@@ -104,7 +135,7 @@ func (in *Inspector) Preorder(types []ast.Node, f func(ast.Node)) {
 // matches an element of the types slice.
 func (in *Inspector) Nodes(types []ast.Node, f func(n ast.Node, push bool) (proceed bool)) {
 	mask := maskOf(types)
-	for i := 0; i < len(in.events); {
+	for i := int32(0); i < int32(len(in.events)); {
 		ev := in.events[i]
 		if ev.index > i {
 			// push
@@ -138,7 +169,7 @@ func (in *Inspector) Nodes(types []ast.Node, f func(n ast.Node, push bool) (proc
 func (in *Inspector) WithStack(types []ast.Node, f func(n ast.Node, push bool, stack []ast.Node) (proceed bool)) {
 	mask := maskOf(types)
 	var stack []ast.Node
-	for i := 0; i < len(in.events); {
+	for i := int32(0); i < int32(len(in.events)); {
 		ev := in.events[i]
 		if ev.index > i {
 			// push
@@ -171,50 +202,83 @@ func (in *Inspector) WithStack(types []ast.Node, f func(n ast.Node, push bool, s
 // traverse builds the table of events representing a traversal.
 func traverse(files []*ast.File) []event {
 	// Preallocate approximate number of events
-	// based on source file extent.
+	// based on source file extent of the declarations.
+	// (We use End-Pos not FileStart-FileEnd to neglect
+	// the effect of long doc comments.)
 	// This makes traverse faster by 4x (!).
 	var extent int
 	for _, f := range files {
 		extent += int(f.End() - f.Pos())
 	}
 	// This estimate is based on the net/http package.
-	capacity := extent * 33 / 100
-	if capacity > 1e6 {
-		capacity = 1e6 // impose some reasonable maximum
+	capacity := min(extent*33/100, 1e6) // impose some reasonable maximum (1M)
+
+	v := &visitor{
+		events: make([]event, 0, capacity),
+		stack:  []item{{index: -1}}, // include an extra event so file nodes have a parent
 	}
-	events := make([]event, 0, capacity)
-
-	var stack []event
-	stack = append(stack, event{}) // include an extra event so file nodes have a parent
-	for _, f := range files {
-		ast.Inspect(f, func(n ast.Node) bool {
-			if n != nil {
-				// push
-				ev := event{
-					node:  n,
-					typ:   0,           // temporarily used to accumulate type bits of subtree
-					index: len(events), // push event temporarily holds own index
-				}
-				stack = append(stack, ev)
-				events = append(events, ev)
-			} else {
-				// pop
-				top := len(stack) - 1
-				ev := stack[top]
-				typ := typeOf(ev.node)
-				push := ev.index
-				parent := top - 1
-
-				events[push].typ = typ            // set type of push
-				stack[parent].typ |= typ | ev.typ // parent's typ contains push and pop's typs.
-				events[push].index = len(events)  // make push refer to pop
-
-				stack = stack[:top]
-				events = append(events, ev)
-			}
-			return true
-		})
+	for _, file := range files {
+		walk(v, edge.Invalid, -1, file)
 	}
-
-	return events
+	return v.events
+}
+
+type visitor struct {
+	events []event
+	stack  []item
+}
+
+type item struct {
+	index            int32  // index of current node's push event
+	parentIndex      int32  // index of parent node's push event
+	typAccum         uint64 // accumulated type bits of current node's descendents
+	edgeKindAndIndex int32  // edge.Kind and index, bit packed
+}
+
+func (v *visitor) push(ek edge.Kind, eindex int, node ast.Node) {
+	var (
+		index       = int32(len(v.events))
+		parentIndex = v.stack[len(v.stack)-1].index
+	)
+	v.events = append(v.events, event{
+		node:   node,
+		parent: parentIndex,
+		typ:    typeOf(node),
+		index:  0, // (pop index is set later by visitor.pop)
+	})
+	v.stack = append(v.stack, item{
+		index:            index,
+		parentIndex:      parentIndex,
+		edgeKindAndIndex: packEdgeKindAndIndex(ek, eindex),
+	})
+
+	// 2B nodes ought to be enough for anyone!
+	if int32(len(v.events)) < 0 {
+		panic("event index exceeded int32")
+	}
+
+	// 32M elements in an []ast.Node ought to be enough for anyone!
+	if ek2, eindex2 := unpackEdgeKindAndIndex(packEdgeKindAndIndex(ek, eindex)); ek2 != ek || eindex2 != eindex {
+		panic("Node slice index exceeded uint25")
+	}
+}
+
+func (v *visitor) pop(node ast.Node) {
+	top := len(v.stack) - 1
+	current := v.stack[top]
+
+	push := &v.events[current.index]
+	parent := &v.stack[top-1]
+
+	push.index = int32(len(v.events))              // make push event refer to pop
+	parent.typAccum |= current.typAccum | push.typ // accumulate type bits into parent
+
+	v.stack = v.stack[:top]
+
+	v.events = append(v.events, event{
+		node:   node,
+		typ:    current.typAccum,
+		index:  current.index,
+		parent: current.edgeKindAndIndex, // see [unpackEdgeKindAndIndex]
+	})
 }

vendor/golang.org/x/tools/go/ast/inspector/iter.go

@@ -0,0 +1,85 @@
+// 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.
+
+//go:build go1.23
+
+package inspector
+
+import (
+	"go/ast"
+	"iter"
+)
+
+// PreorderSeq returns an iterator that visits all the
+// nodes of the files supplied to New in depth-first order.
+// It visits each node n before n's children.
+// The complete traversal sequence is determined by ast.Inspect.
+//
+// The types argument, if non-empty, enables type-based
+// filtering of events: only nodes whose type matches an
+// element of the types slice are included in the sequence.
+func (in *Inspector) PreorderSeq(types ...ast.Node) iter.Seq[ast.Node] {
+
+	// This implementation is identical to Preorder,
+	// except that it supports breaking out of the loop.
+
+	return func(yield func(ast.Node) bool) {
+		mask := maskOf(types)
+		for i := int32(0); i < int32(len(in.events)); {
+			ev := in.events[i]
+			if ev.index > i {
+				// push
+				if ev.typ&mask != 0 {
+					if !yield(ev.node) {
+						break
+					}
+				}
+				pop := ev.index
+				if in.events[pop].typ&mask == 0 {
+					// Subtrees do not contain types: skip them and pop.
+					i = pop + 1
+					continue
+				}
+			}
+			i++
+		}
+	}
+}
+
+// All[N] returns an iterator over all the nodes of type N.
+// N must be a pointer-to-struct type that implements ast.Node.
+//
+// Example:
+//
+//	for call := range All[*ast.CallExpr](in) { ... }
+func All[N interface {
+	*S
+	ast.Node
+}, S any](in *Inspector) iter.Seq[N] {
+
+	// To avoid additional dynamic call overheads,
+	// we duplicate rather than call the logic of PreorderSeq.
+
+	mask := typeOf((N)(nil))
+	return func(yield func(N) bool) {
+		for i := int32(0); i < int32(len(in.events)); {
+			ev := in.events[i]
+			if ev.index > i {
+				// push
+				if ev.typ&mask != 0 {
+					if !yield(ev.node.(N)) {
+						break
+					}
+				}
+				pop := ev.index
+				if in.events[pop].typ&mask == 0 {
+					// Subtrees do not contain types: skip them and pop.
+					i = pop + 1
+					continue
+				}
+			}
+			i++
+		}
+	}
+}

vendor/golang.org/x/tools/go/ast/inspector/typeof.go

@@ -12,6 +12,8 @@ package inspector
 import (
 	"go/ast"
 	"math"
+
+	_ "unsafe"
 )
 
 const (
@@ -215,8 +217,9 @@ func typeOf(n ast.Node) uint64 {
 	return 0
 }
 
+//go:linkname maskOf
 func maskOf(nodes []ast.Node) uint64 {
-	if nodes == nil {
+	if len(nodes) == 0 {
 		return math.MaxUint64 // match all node types
 	}
 	var mask uint64

vendor/golang.org/x/tools/go/ast/inspector/walk.go

@@ -0,0 +1,341 @@
+// Copyright 2025 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 inspector
+
+// This file is a fork of ast.Inspect to reduce unnecessary dynamic
+// calls and to gather edge information.
+//
+// Consistency with the original is ensured by TestInspectAllNodes.
+
+import (
+	"fmt"
+	"go/ast"
+
+	"golang.org/x/tools/internal/astutil/edge"
+)
+
+func walkList[N ast.Node](v *visitor, ek edge.Kind, list []N) {
+	for i, node := range list {
+		walk(v, ek, i, node)
+	}
+}
+
+func walk(v *visitor, ek edge.Kind, index int, node ast.Node) {
+	v.push(ek, index, node)
+
+	// walk children
+	// (the order of the cases matches the order
+	// of the corresponding node types in ast.go)
+	switch n := node.(type) {
+	// Comments and fields
+	case *ast.Comment:
+		// nothing to do
+
+	case *ast.CommentGroup:
+		walkList(v, edge.CommentGroup_List, n.List)
+
+	case *ast.Field:
+		if n.Doc != nil {
+			walk(v, edge.Field_Doc, -1, n.Doc)
+		}
+		walkList(v, edge.Field_Names, n.Names)
+		if n.Type != nil {
+			walk(v, edge.Field_Type, -1, n.Type)
+		}
+		if n.Tag != nil {
+			walk(v, edge.Field_Tag, -1, n.Tag)
+		}
+		if n.Comment != nil {
+			walk(v, edge.Field_Comment, -1, n.Comment)
+		}
+
+	case *ast.FieldList:
+		walkList(v, edge.FieldList_List, n.List)
+
+	// Expressions
+	case *ast.BadExpr, *ast.Ident, *ast.BasicLit:
+		// nothing to do
+
+	case *ast.Ellipsis:
+		if n.Elt != nil {
+			walk(v, edge.Ellipsis_Elt, -1, n.Elt)
+		}
+
+	case *ast.FuncLit:
+		walk(v, edge.FuncLit_Type, -1, n.Type)
+		walk(v, edge.FuncLit_Body, -1, n.Body)
+
+	case *ast.CompositeLit:
+		if n.Type != nil {
+			walk(v, edge.CompositeLit_Type, -1, n.Type)
+		}
+		walkList(v, edge.CompositeLit_Elts, n.Elts)
+
+	case *ast.ParenExpr:
+		walk(v, edge.ParenExpr_X, -1, n.X)
+
+	case *ast.SelectorExpr:
+		walk(v, edge.SelectorExpr_X, -1, n.X)
+		walk(v, edge.SelectorExpr_Sel, -1, n.Sel)
+
+	case *ast.IndexExpr:
+		walk(v, edge.IndexExpr_X, -1, n.X)
+		walk(v, edge.IndexExpr_Index, -1, n.Index)
+
+	case *ast.IndexListExpr:
+		walk(v, edge.IndexListExpr_X, -1, n.X)
+		walkList(v, edge.IndexListExpr_Indices, n.Indices)
+
+	case *ast.SliceExpr:
+		walk(v, edge.SliceExpr_X, -1, n.X)
+		if n.Low != nil {
+			walk(v, edge.SliceExpr_Low, -1, n.Low)
+		}
+		if n.High != nil {
+			walk(v, edge.SliceExpr_High, -1, n.High)
+		}
+		if n.Max != nil {
+			walk(v, edge.SliceExpr_Max, -1, n.Max)
+		}
+
+	case *ast.TypeAssertExpr:
+		walk(v, edge.TypeAssertExpr_X, -1, n.X)
+		if n.Type != nil {
+			walk(v, edge.TypeAssertExpr_Type, -1, n.Type)
+		}
+
+	case *ast.CallExpr:
+		walk(v, edge.CallExpr_Fun, -1, n.Fun)
+		walkList(v, edge.CallExpr_Args, n.Args)
+
+	case *ast.StarExpr:
+		walk(v, edge.StarExpr_X, -1, n.X)
+
+	case *ast.UnaryExpr:
+		walk(v, edge.UnaryExpr_X, -1, n.X)
+
+	case *ast.BinaryExpr:
+		walk(v, edge.BinaryExpr_X, -1, n.X)
+		walk(v, edge.BinaryExpr_Y, -1, n.Y)
+
+	case *ast.KeyValueExpr:
+		walk(v, edge.KeyValueExpr_Key, -1, n.Key)
+		walk(v, edge.KeyValueExpr_Value, -1, n.Value)
+
+	// Types
+	case *ast.ArrayType:
+		if n.Len != nil {
+			walk(v, edge.ArrayType_Len, -1, n.Len)
+		}
+		walk(v, edge.ArrayType_Elt, -1, n.Elt)
+
+	case *ast.StructType:
+		walk(v, edge.StructType_Fields, -1, n.Fields)
+
+	case *ast.FuncType:
+		if n.TypeParams != nil {
+			walk(v, edge.FuncType_TypeParams, -1, n.TypeParams)
+		}
+		if n.Params != nil {
+			walk(v, edge.FuncType_Params, -1, n.Params)
+		}
+		if n.Results != nil {
+			walk(v, edge.FuncType_Results, -1, n.Results)
+		}
+
+	case *ast.InterfaceType:
+		walk(v, edge.InterfaceType_Methods, -1, n.Methods)
+
+	case *ast.MapType:
+		walk(v, edge.MapType_Key, -1, n.Key)
+		walk(v, edge.MapType_Value, -1, n.Value)
+
+	case *ast.ChanType:
+		walk(v, edge.ChanType_Value, -1, n.Value)
+
+	// Statements
+	case *ast.BadStmt:
+		// nothing to do
+
+	case *ast.DeclStmt:
+		walk(v, edge.DeclStmt_Decl, -1, n.Decl)
+
+	case *ast.EmptyStmt:
+		// nothing to do
+
+	case *ast.LabeledStmt:
+		walk(v, edge.LabeledStmt_Label, -1, n.Label)
+		walk(v, edge.LabeledStmt_Stmt, -1, n.Stmt)
+
+	case *ast.ExprStmt:
+		walk(v, edge.ExprStmt_X, -1, n.X)
+
+	case *ast.SendStmt:
+		walk(v, edge.SendStmt_Chan, -1, n.Chan)
+		walk(v, edge.SendStmt_Value, -1, n.Value)
+
+	case *ast.IncDecStmt:
+		walk(v, edge.IncDecStmt_X, -1, n.X)
+
+	case *ast.AssignStmt:
+		walkList(v, edge.AssignStmt_Lhs, n.Lhs)
+		walkList(v, edge.AssignStmt_Rhs, n.Rhs)
+
+	case *ast.GoStmt:
+		walk(v, edge.GoStmt_Call, -1, n.Call)
+
+	case *ast.DeferStmt:
+		walk(v, edge.DeferStmt_Call, -1, n.Call)
+
+	case *ast.ReturnStmt:
+		walkList(v, edge.ReturnStmt_Results, n.Results)
+
+	case *ast.BranchStmt:
+		if n.Label != nil {
+			walk(v, edge.BranchStmt_Label, -1, n.Label)
+		}
+
+	case *ast.BlockStmt:
+		walkList(v, edge.BlockStmt_List, n.List)
+
+	case *ast.IfStmt:
+		if n.Init != nil {
+			walk(v, edge.IfStmt_Init, -1, n.Init)
+		}
+		walk(v, edge.IfStmt_Cond, -1, n.Cond)
+		walk(v, edge.IfStmt_Body, -1, n.Body)
+		if n.Else != nil {
+			walk(v, edge.IfStmt_Else, -1, n.Else)
+		}
+
+	case *ast.CaseClause:
+		walkList(v, edge.CaseClause_List, n.List)
+		walkList(v, edge.CaseClause_Body, n.Body)
+
+	case *ast.SwitchStmt:
+		if n.Init != nil {
+			walk(v, edge.SwitchStmt_Init, -1, n.Init)
+		}
+		if n.Tag != nil {
+			walk(v, edge.SwitchStmt_Tag, -1, n.Tag)
+		}
+		walk(v, edge.SwitchStmt_Body, -1, n.Body)
+
+	case *ast.TypeSwitchStmt:
+		if n.Init != nil {
+			walk(v, edge.TypeSwitchStmt_Init, -1, n.Init)
+		}
+		walk(v, edge.TypeSwitchStmt_Assign, -1, n.Assign)
+		walk(v, edge.TypeSwitchStmt_Body, -1, n.Body)
+
+	case *ast.CommClause:
+		if n.Comm != nil {
+			walk(v, edge.CommClause_Comm, -1, n.Comm)
+		}
+		walkList(v, edge.CommClause_Body, n.Body)
+
+	case *ast.SelectStmt:
+		walk(v, edge.SelectStmt_Body, -1, n.Body)
+
+	case *ast.ForStmt:
+		if n.Init != nil {
+			walk(v, edge.ForStmt_Init, -1, n.Init)
+		}
+		if n.Cond != nil {
+			walk(v, edge.ForStmt_Cond, -1, n.Cond)
+		}
+		if n.Post != nil {
+			walk(v, edge.ForStmt_Post, -1, n.Post)
+		}
+		walk(v, edge.ForStmt_Body, -1, n.Body)
+
+	case *ast.RangeStmt:
+		if n.Key != nil {
+			walk(v, edge.RangeStmt_Key, -1, n.Key)
+		}
+		if n.Value != nil {
+			walk(v, edge.RangeStmt_Value, -1, n.Value)
+		}
+		walk(v, edge.RangeStmt_X, -1, n.X)
+		walk(v, edge.RangeStmt_Body, -1, n.Body)
+
+	// Declarations
+	case *ast.ImportSpec:
+		if n.Doc != nil {
+			walk(v, edge.ImportSpec_Doc, -1, n.Doc)
+		}
+		if n.Name != nil {
+			walk(v, edge.ImportSpec_Name, -1, n.Name)
+		}
+		walk(v, edge.ImportSpec_Path, -1, n.Path)
+		if n.Comment != nil {
+			walk(v, edge.ImportSpec_Comment, -1, n.Comment)
+		}
+
+	case *ast.ValueSpec:
+		if n.Doc != nil {
+			walk(v, edge.ValueSpec_Doc, -1, n.Doc)
+		}
+		walkList(v, edge.ValueSpec_Names, n.Names)
+		if n.Type != nil {
+			walk(v, edge.ValueSpec_Type, -1, n.Type)
+		}
+		walkList(v, edge.ValueSpec_Values, n.Values)
+		if n.Comment != nil {
+			walk(v, edge.ValueSpec_Comment, -1, n.Comment)
+		}
+
+	case *ast.TypeSpec:
+		if n.Doc != nil {
+			walk(v, edge.TypeSpec_Doc, -1, n.Doc)
+		}
+		walk(v, edge.TypeSpec_Name, -1, n.Name)
+		if n.TypeParams != nil {
+			walk(v, edge.TypeSpec_TypeParams, -1, n.TypeParams)
+		}
+		walk(v, edge.TypeSpec_Type, -1, n.Type)
+		if n.Comment != nil {
+			walk(v, edge.TypeSpec_Comment, -1, n.Comment)
+		}
+
+	case *ast.BadDecl:
+		// nothing to do
+
+	case *ast.GenDecl:
+		if n.Doc != nil {
+			walk(v, edge.GenDecl_Doc, -1, n.Doc)
+		}
+		walkList(v, edge.GenDecl_Specs, n.Specs)
+
+	case *ast.FuncDecl:
+		if n.Doc != nil {
+			walk(v, edge.FuncDecl_Doc, -1, n.Doc)
+		}
+		if n.Recv != nil {
+			walk(v, edge.FuncDecl_Recv, -1, n.Recv)
+		}
+		walk(v, edge.FuncDecl_Name, -1, n.Name)
+		walk(v, edge.FuncDecl_Type, -1, n.Type)
+		if n.Body != nil {
+			walk(v, edge.FuncDecl_Body, -1, n.Body)
+		}
+
+	case *ast.File:
+		if n.Doc != nil {
+			walk(v, edge.File_Doc, -1, n.Doc)
+		}
+		walk(v, edge.File_Name, -1, n.Name)
+		walkList(v, edge.File_Decls, n.Decls)
+		// don't walk n.Comments - they have been
+		// visited already through the individual
+		// nodes
+
+	default:
+		// (includes *ast.Package)
+		panic(fmt.Sprintf("Walk: unexpected node type %T", n))
+	}
+
+	v.pop(node)
+}

vendor/golang.org/x/tools/go/gcexportdata/gcexportdata.go

@@ -2,22 +2,64 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package gcexportdata provides functions for locating, reading, and
-// writing export data files containing type information produced by the
-// gc compiler.  This package supports go1.7 export data format and all
-// later versions.
+// Package gcexportdata provides functions for reading and writing
+// export data, which is a serialized description of the API of a Go
+// package including the names, kinds, types, and locations of all
+// exported declarations.
 //
-// Although it might seem convenient for this package to live alongside
-// go/types in the standard library, this would cause version skew
-// problems for developer tools that use it, since they must be able to
-// consume the outputs of the gc compiler both before and after a Go
-// update such as from Go 1.7 to Go 1.8.  Because this package lives in
-// golang.org/x/tools, sites can update their version of this repo some
-// time before the Go 1.8 release and rebuild and redeploy their
-// developer tools, which will then be able to consume both Go 1.7 and
-// Go 1.8 export data files, so they will work before and after the
-// Go update. (See discussion at https://golang.org/issue/15651.)
-package gcexportdata // import "golang.org/x/tools/go/gcexportdata"
+// The standard Go compiler (cmd/compile) writes an export data file
+// for each package it compiles, which it later reads when compiling
+// packages that import the earlier one. The compiler must thus
+// contain logic to both write and read export data.
+// (See the "Export" section in the cmd/compile/README file.)
+//
+// The [Read] function in this package can read files produced by the
+// compiler, producing [go/types] data structures. As a matter of
+// policy, Read supports export data files produced by only the last
+// two Go releases plus tip; see https://go.dev/issue/68898. The
+// export data files produced by the compiler contain additional
+// details related to generics, inlining, and other optimizations that
+// cannot be decoded by the [Read] function.
+//
+// In files written by the compiler, the export data is not at the
+// start of the file. Before calling Read, use [NewReader] to locate
+// the desired portion of the file.
+//
+// The [Write] function in this package encodes the exported API of a
+// Go package ([types.Package]) as a file. Such files can be later
+// decoded by Read, but cannot be consumed by the compiler.
+//
+// # Future changes
+//
+// Although Read supports the formats written by both Write and the
+// compiler, the two are quite different, and there is an open
+// proposal (https://go.dev/issue/69491) to separate these APIs.
+//
+// Under that proposal, this package would ultimately provide only the
+// Read operation for compiler export data, which must be defined in
+// this module (golang.org/x/tools), not in the standard library, to
+// avoid version skew for developer tools that need to read compiler
+// export data both before and after a Go release, such as from Go
+// 1.23 to Go 1.24. Because this package lives in the tools module,
+// clients can update their version of the module some time before the
+// Go 1.24 release and rebuild and redeploy their tools, which will
+// then be able to consume both Go 1.23 and Go 1.24 export data files,
+// so they will work before and after the Go update. (See discussion
+// at https://go.dev/issue/15651.)
+//
+// The operations to import and export [go/types] data structures
+// would be defined in the go/types package as Import and Export.
+// [Write] would (eventually) delegate to Export,
+// and [Read], when it detects a file produced by Export,
+// would delegate to Import.
+//
+// # Deprecations
+//
+// The [NewImporter] and [Find] functions are deprecated and should
+// not be used in new code. The [WriteBundle] and [ReadBundle]
+// functions are experimental, and there is an open proposal to
+// deprecate them (https://go.dev/issue/69573).
+package gcexportdata
 
 import (
 	"bufio"
@@ -64,24 +106,18 @@ func Find(importPath, srcDir string) (filename, path string) {
 // additional trailing data beyond the end of the export data.
 func NewReader(r io.Reader) (io.Reader, error) {
 	buf := bufio.NewReader(r)
-	_, size, err := gcimporter.FindExportData(buf)
+	size, err := gcimporter.FindExportData(buf)
 	if err != nil {
 		return nil, err
 	}
 
-	if size >= 0 {
-		// We were given an archive and found the __.PKGDEF in it.
-		// This tells us the size of the export data, and we don't
-		// need to return the entire file.
-		return &io.LimitedReader{
-			R: buf,
-			N: size,
-		}, nil
-	} else {
-		// We were given an object file. As such, we don't know how large
-		// the export data is and must return the entire file.
-		return buf, nil
-	}
+	// We were given an archive and found the __.PKGDEF in it.
+	// This tells us the size of the export data, and we don't
+	// need to return the entire file.
+	return &io.LimitedReader{
+		R: buf,
+		N: size,
+	}, nil
 }
 
 // readAll works the same way as io.ReadAll, but avoids allocations and copies
@@ -100,6 +136,11 @@ func readAll(r io.Reader) ([]byte, error) {
 // Read reads export data from in, decodes it, and returns type
 // information for the package.
 //
+// Read is capable of reading export data produced by [Write] at the
+// same source code version, or by the last two Go releases (plus tip)
+// of the standard Go compiler. Reading files from older compilers may
+// produce an error.
+//
 // The package path (effectively its linker symbol prefix) is
 // specified by path, since unlike the package name, this information
 // may not be recorded in the export data.
@@ -128,14 +169,26 @@ func Read(in io.Reader, fset *token.FileSet, imports map[string]*types.Package,
 	// (from "version"). Select appropriate importer.
 	if len(data) > 0 {
 		switch data[0] {
-		case 'v', 'c', 'd': // binary, till go1.10
+		case 'v', 'c', 'd':
+			// binary, produced by cmd/compile till go1.10
 			return nil, fmt.Errorf("binary (%c) import format is no longer supported", data[0])
 
-		case 'i': // indexed, till go1.19
+		case 'i':
+			// indexed, produced by cmd/compile till go1.19,
+			// and also by [Write].
+			//
+			// If proposal #69491 is accepted, go/types
+			// serialization will be implemented by
+			// types.Export, to which Write would eventually
+			// delegate (explicitly dropping any pretence at
+			// inter-version Write-Read compatibility).
+			// This [Read] function would delegate to types.Import
+			// when it detects that the file was produced by Export.
 			_, pkg, err := gcimporter.IImportData(fset, imports, data[1:], path)
 			return pkg, err
 
-		case 'u': // unified, from go1.20
+		case 'u':
+			// unified, produced by cmd/compile since go1.20
 			_, pkg, err := gcimporter.UImportData(fset, imports, data[1:], path)
 			return pkg, err
 

vendor/golang.org/x/tools/go/internal/packagesdriver/sizes.go

@@ -1,54 +0,0 @@
-// Copyright 2018 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 packagesdriver fetches type sizes for go/packages and go/analysis.
-package packagesdriver
-
-import (
-	"context"
-	"fmt"
-	"strings"
-
-	"golang.org/x/tools/internal/gocommand"
-)
-
-// TODO(adonovan): move back into go/packages.
-func GetSizesForArgsGolist(ctx context.Context, inv gocommand.Invocation, gocmdRunner *gocommand.Runner) (string, string, error) {
-	inv.Verb = "list"
-	inv.Args = []string{"-f", "{{context.GOARCH}} {{context.Compiler}}", "--", "unsafe"}
-	stdout, stderr, friendlyErr, rawErr := gocmdRunner.RunRaw(ctx, inv)
-	var goarch, compiler string
-	if rawErr != nil {
-		rawErrMsg := rawErr.Error()
-		if strings.Contains(rawErrMsg, "cannot find main module") ||
-			strings.Contains(rawErrMsg, "go.mod file not found") {
-			// User's running outside of a module.
-			// All bets are off. Get GOARCH and guess compiler is gc.
-			// TODO(matloob): Is this a problem in practice?
-			inv.Verb = "env"
-			inv.Args = []string{"GOARCH"}
-			envout, enverr := gocmdRunner.Run(ctx, inv)
-			if enverr != nil {
-				return "", "", enverr
-			}
-			goarch = strings.TrimSpace(envout.String())
-			compiler = "gc"
-		} else if friendlyErr != nil {
-			return "", "", friendlyErr
-		} else {
-			// This should be unreachable, but be defensive
-			// in case RunRaw's error results are inconsistent.
-			return "", "", rawErr
-		}
-	} else {
-		fields := strings.Fields(stdout.String())
-		if len(fields) < 2 {
-			return "", "", fmt.Errorf("could not parse GOARCH and Go compiler in format \"<GOARCH> <compiler>\":\nstdout: <<%s>>\nstderr: <<%s>>",
-				stdout.String(), stderr.String())
-		}
-		goarch = fields[0]
-		compiler = fields[1]
-	}
-	return compiler, goarch, nil
-}

vendor/golang.org/x/tools/go/packages/doc.go

@@ -64,7 +64,7 @@ graph using the Imports fields.
 
 The Load function can be configured by passing a pointer to a Config as
 the first argument. A nil Config is equivalent to the zero Config, which
-causes Load to run in LoadFiles mode, collecting minimal information.
+causes Load to run in [LoadFiles] mode, collecting minimal information.
 See the documentation for type Config for details.
 
 As noted earlier, the Config.Mode controls the amount of detail
@@ -72,14 +72,14 @@ reported about the loaded packages. See the documentation for type LoadMode
 for details.
 
 Most tools should pass their command-line arguments (after any flags)
-uninterpreted to [Load], so that it can interpret them
+uninterpreted to Load, so that it can interpret them
 according to the conventions of the underlying build system.
 
 See the Example function for typical usage.
 
 # The driver protocol
 
-[Load] may be used to load Go packages even in Go projects that use
+Load may be used to load Go packages even in Go projects that use
 alternative build systems, by installing an appropriate "driver"
 program for the build system and specifying its location in the
 GOPACKAGESDRIVER environment variable.
@@ -97,6 +97,15 @@ JSON-encoded [DriverRequest] message providing additional information
 is written to the driver's standard input. The driver must write a
 JSON-encoded [DriverResponse] message to its standard output. (This
 message differs from the JSON schema produced by 'go list'.)
+
+The value of the PWD environment variable seen by the driver process
+is the preferred name of its working directory. (The working directory
+may have other aliases due to symbolic links; see the comment on the
+Dir field of [exec.Cmd] for related information.)
+When the driver process emits in its response the name of a file
+that is a descendant of this directory, it must use an absolute path
+that has the value of PWD as a prefix, to ensure that the returned
+filenames satisfy the original query.
 */
 package packages // import "golang.org/x/tools/go/packages"
 

vendor/golang.org/x/tools/go/packages/external.go

@@ -13,6 +13,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"slices"
 	"strings"
 )
 
@@ -79,10 +80,10 @@ type DriverResponse struct {
 
 // driver is the type for functions that query the build system for the
 // packages named by the patterns.
-type driver func(cfg *Config, patterns ...string) (*DriverResponse, error)
+type driver func(cfg *Config, patterns []string) (*DriverResponse, error)
 
 // findExternalDriver returns the file path of a tool that supplies
-// the build system package structure, or "" if not found."
+// the build system package structure, or "" if not found.
 // If GOPACKAGESDRIVER is set in the environment findExternalTool returns its
 // value, otherwise it searches for a binary named gopackagesdriver on the PATH.
 func findExternalDriver(cfg *Config) driver {
@@ -103,7 +104,7 @@ func findExternalDriver(cfg *Config) driver {
 			return nil
 		}
 	}
-	return func(cfg *Config, words ...string) (*DriverResponse, error) {
+	return func(cfg *Config, patterns []string) (*DriverResponse, error) {
 		req, err := json.Marshal(DriverRequest{
 			Mode:       cfg.Mode,
 			Env:        cfg.Env,
@@ -117,7 +118,7 @@ func findExternalDriver(cfg *Config) driver {
 
 		buf := new(bytes.Buffer)
 		stderr := new(bytes.Buffer)
-		cmd := exec.CommandContext(cfg.Context, tool, words...)
+		cmd := exec.CommandContext(cfg.Context, tool, patterns...)
 		cmd.Dir = cfg.Dir
 		// The cwd gets resolved to the real path. On Darwin, where
 		// /tmp is a symlink, this breaks anything that expects the
@@ -131,7 +132,7 @@ func findExternalDriver(cfg *Config) driver {
 		// command.
 		//
 		// (See similar trick in Invocation.run in ../../internal/gocommand/invoke.go)
-		cmd.Env = append(slicesClip(cfg.Env), "PWD="+cfg.Dir)
+		cmd.Env = append(slices.Clip(cfg.Env), "PWD="+cfg.Dir)
 		cmd.Stdin = bytes.NewReader(req)
 		cmd.Stdout = buf
 		cmd.Stderr = stderr
@@ -150,7 +151,3 @@ func findExternalDriver(cfg *Config) driver {
 		return &response, nil
 	}
 }
-
-// slicesClip removes unused capacity from the slice, returning s[:len(s):len(s)].
-// TODO(adonovan): use go1.21 slices.Clip.
-func slicesClip[S ~[]E, E any](s S) S { return s[:len(s):len(s)] }

vendor/golang.org/x/tools/go/packages/golist.go

@@ -21,7 +21,6 @@ import (
 	"sync"
 	"unicode"
 
-	"golang.org/x/tools/go/internal/packagesdriver"
 	"golang.org/x/tools/internal/gocommand"
 	"golang.org/x/tools/internal/packagesinternal"
 )
@@ -81,6 +80,12 @@ type golistState struct {
 	cfg *Config
 	ctx context.Context
 
+	runner *gocommand.Runner
+
+	// overlay is the JSON file that encodes the Config.Overlay
+	// mapping, used by 'go list -overlay=...'.
+	overlay string
+
 	envOnce    sync.Once
 	goEnvError error
 	goEnv      map[string]string
@@ -128,7 +133,10 @@ func (state *golistState) mustGetEnv() map[string]string {
 // goListDriver uses the go list command to interpret the patterns and produce
 // the build system package structure.
 // See driver for more details.
-func goListDriver(cfg *Config, patterns ...string) (_ *DriverResponse, err error) {
+//
+// overlay is the JSON file that encodes the cfg.Overlay
+// mapping, used by 'go list -overlay=...'
+func goListDriver(cfg *Config, runner *gocommand.Runner, overlay string, patterns []string) (_ *DriverResponse, err error) {
 	// Make sure that any asynchronous go commands are killed when we return.
 	parentCtx := cfg.Context
 	if parentCtx == nil {
@@ -143,13 +151,15 @@ func goListDriver(cfg *Config, patterns ...string) (_ *DriverResponse, err error
 		cfg:        cfg,
 		ctx:        ctx,
 		vendorDirs: map[string]bool{},
+		overlay:    overlay,
+		runner:     runner,
 	}
 
 	// Fill in response.Sizes asynchronously if necessary.
-	if cfg.Mode&NeedTypesSizes != 0 || cfg.Mode&NeedTypes != 0 {
+	if cfg.Mode&NeedTypesSizes != 0 || cfg.Mode&(NeedTypes|NeedTypesInfo) != 0 {
 		errCh := make(chan error)
 		go func() {
-			compiler, arch, err := packagesdriver.GetSizesForArgsGolist(ctx, state.cfgInvocation(), cfg.gocmdRunner)
+			compiler, arch, err := getSizesForArgs(ctx, state.cfgInvocation(), runner)
 			response.dr.Compiler = compiler
 			response.dr.Arch = arch
 			errCh <- err
@@ -312,6 +322,7 @@ type jsonPackage struct {
 	ImportPath        string
 	Dir               string
 	Name              string
+	Target            string
 	Export            string
 	GoFiles           []string
 	CompiledGoFiles   []string
@@ -495,13 +506,15 @@ func (state *golistState) createDriverResponse(words ...string) (*DriverResponse
 		pkg := &Package{
 			Name:            p.Name,
 			ID:              p.ImportPath,
+			Dir:             p.Dir,
+			Target:          p.Target,
 			GoFiles:         absJoin(p.Dir, p.GoFiles, p.CgoFiles),
 			CompiledGoFiles: absJoin(p.Dir, p.CompiledGoFiles),
 			OtherFiles:      absJoin(p.Dir, otherFiles(p)...),
 			EmbedFiles:      absJoin(p.Dir, p.EmbedFiles),
 			EmbedPatterns:   absJoin(p.Dir, p.EmbedPatterns),
 			IgnoredFiles:    absJoin(p.Dir, p.IgnoredGoFiles, p.IgnoredOtherFiles),
-			forTest:         p.ForTest,
+			ForTest:         p.ForTest,
 			depsErrors:      p.DepsErrors,
 			Module:          p.Module,
 		}
@@ -682,7 +695,7 @@ func (state *golistState) shouldAddFilenameFromError(p *jsonPackage) bool {
 // getGoVersion returns the effective minor version of the go command.
 func (state *golistState) getGoVersion() (int, error) {
 	state.goVersionOnce.Do(func() {
-		state.goVersion, state.goVersionError = gocommand.GoVersion(state.ctx, state.cfgInvocation(), state.cfg.gocmdRunner)
+		state.goVersion, state.goVersionError = gocommand.GoVersion(state.ctx, state.cfgInvocation(), state.runner)
 	})
 	return state.goVersion, state.goVersionError
 }
@@ -752,7 +765,7 @@ func jsonFlag(cfg *Config, goVersion int) string {
 		}
 	}
 	addFields("Name", "ImportPath", "Error") // These fields are always needed
-	if cfg.Mode&NeedFiles != 0 || cfg.Mode&NeedTypes != 0 {
+	if cfg.Mode&NeedFiles != 0 || cfg.Mode&(NeedTypes|NeedTypesInfo) != 0 {
 		addFields("Dir", "GoFiles", "IgnoredGoFiles", "IgnoredOtherFiles", "CFiles",
 			"CgoFiles", "CXXFiles", "MFiles", "HFiles", "FFiles", "SFiles",
 			"SwigFiles", "SwigCXXFiles", "SysoFiles")
@@ -760,7 +773,7 @@ func jsonFlag(cfg *Config, goVersion int) string {
 			addFields("TestGoFiles", "XTestGoFiles")
 		}
 	}
-	if cfg.Mode&NeedTypes != 0 {
+	if cfg.Mode&(NeedTypes|NeedTypesInfo) != 0 {
 		// CompiledGoFiles seems to be required for the test case TestCgoNoSyntax,
 		// even when -compiled isn't passed in.
 		// TODO(#52435): Should we make the test ask for -compiled, or automatically
@@ -785,7 +798,7 @@ func jsonFlag(cfg *Config, goVersion int) string {
 		// Request Dir in the unlikely case Export is not absolute.
 		addFields("Dir", "Export")
 	}
-	if cfg.Mode&needInternalForTest != 0 {
+	if cfg.Mode&NeedForTest != 0 {
 		addFields("ForTest")
 	}
 	if cfg.Mode&needInternalDepsErrors != 0 {
@@ -800,6 +813,9 @@ func jsonFlag(cfg *Config, goVersion int) string {
 	if cfg.Mode&NeedEmbedPatterns != 0 {
 		addFields("EmbedPatterns")
 	}
+	if cfg.Mode&NeedTarget != 0 {
+		addFields("Target")
+	}
 	return "-json=" + strings.Join(fields, ",")
 }
 
@@ -841,7 +857,7 @@ func (state *golistState) cfgInvocation() gocommand.Invocation {
 		Env:        cfg.Env,
 		Logf:       cfg.Logf,
 		WorkingDir: cfg.Dir,
-		Overlay:    cfg.goListOverlayFile,
+		Overlay:    state.overlay,
 	}
 }
 
@@ -852,11 +868,8 @@ func (state *golistState) invokeGo(verb string, args ...string) (*bytes.Buffer,
 	inv := state.cfgInvocation()
 	inv.Verb = verb
 	inv.Args = args
-	gocmdRunner := cfg.gocmdRunner
-	if gocmdRunner == nil {
-		gocmdRunner = &gocommand.Runner{}
-	}
-	stdout, stderr, friendlyErr, err := gocmdRunner.RunRaw(cfg.Context, inv)
+
+	stdout, stderr, friendlyErr, err := state.runner.RunRaw(cfg.Context, inv)
 	if err != nil {
 		// Check for 'go' executable not being found.
 		if ee, ok := err.(*exec.Error); ok && ee.Err == exec.ErrNotFound {
@@ -880,6 +893,12 @@ func (state *golistState) invokeGo(verb string, args ...string) (*bytes.Buffer,
 			return nil, friendlyErr
 		}
 
+		// Return an error if 'go list' failed due to missing tools in
+		// $GOROOT/pkg/tool/$GOOS_$GOARCH (#69606).
+		if len(stderr.String()) > 0 && strings.Contains(stderr.String(), `go: no such tool`) {
+			return nil, friendlyErr
+		}
+
 		// Is there an error running the C compiler in cgo? This will be reported in the "Error" field
 		// and should be suppressed by go list -e.
 		//
@@ -1024,3 +1043,44 @@ func cmdDebugStr(cmd *exec.Cmd) string {
 	}
 	return fmt.Sprintf("GOROOT=%v GOPATH=%v GO111MODULE=%v GOPROXY=%v PWD=%v %v", env["GOROOT"], env["GOPATH"], env["GO111MODULE"], env["GOPROXY"], env["PWD"], strings.Join(args, " "))
 }
+
+// getSizesForArgs queries 'go list' for the appropriate
+// Compiler and GOARCH arguments to pass to [types.SizesFor].
+func getSizesForArgs(ctx context.Context, inv gocommand.Invocation, gocmdRunner *gocommand.Runner) (string, string, error) {
+	inv.Verb = "list"
+	inv.Args = []string{"-f", "{{context.GOARCH}} {{context.Compiler}}", "--", "unsafe"}
+	stdout, stderr, friendlyErr, rawErr := gocmdRunner.RunRaw(ctx, inv)
+	var goarch, compiler string
+	if rawErr != nil {
+		rawErrMsg := rawErr.Error()
+		if strings.Contains(rawErrMsg, "cannot find main module") ||
+			strings.Contains(rawErrMsg, "go.mod file not found") {
+			// User's running outside of a module.
+			// All bets are off. Get GOARCH and guess compiler is gc.
+			// TODO(matloob): Is this a problem in practice?
+			inv.Verb = "env"
+			inv.Args = []string{"GOARCH"}
+			envout, enverr := gocmdRunner.Run(ctx, inv)
+			if enverr != nil {
+				return "", "", enverr
+			}
+			goarch = strings.TrimSpace(envout.String())
+			compiler = "gc"
+		} else if friendlyErr != nil {
+			return "", "", friendlyErr
+		} else {
+			// This should be unreachable, but be defensive
+			// in case RunRaw's error results are inconsistent.
+			return "", "", rawErr
+		}
+	} else {
+		fields := strings.Fields(stdout.String())
+		if len(fields) < 2 {
+			return "", "", fmt.Errorf("could not parse GOARCH and Go compiler in format \"<GOARCH> <compiler>\":\nstdout: <<%s>>\nstderr: <<%s>>",
+				stdout.String(), stderr.String())
+		}
+		goarch = fields[0]
+		compiler = fields[1]
+	}
+	return compiler, goarch, nil
+}

vendor/golang.org/x/tools/go/packages/loadmode_string.go

@@ -9,49 +9,48 @@ import (
 	"strings"
 )
 
-var allModes = []LoadMode{
-	NeedName,
-	NeedFiles,
-	NeedCompiledGoFiles,
-	NeedImports,
-	NeedDeps,
-	NeedExportFile,
-	NeedTypes,
-	NeedSyntax,
-	NeedTypesInfo,
-	NeedTypesSizes,
+var modes = [...]struct {
+	mode LoadMode
+	name string
+}{
+	{NeedName, "NeedName"},
+	{NeedFiles, "NeedFiles"},
+	{NeedCompiledGoFiles, "NeedCompiledGoFiles"},
+	{NeedImports, "NeedImports"},
+	{NeedDeps, "NeedDeps"},
+	{NeedExportFile, "NeedExportFile"},
+	{NeedTypes, "NeedTypes"},
+	{NeedSyntax, "NeedSyntax"},
+	{NeedTypesInfo, "NeedTypesInfo"},
+	{NeedTypesSizes, "NeedTypesSizes"},
+	{NeedForTest, "NeedForTest"},
+	{NeedModule, "NeedModule"},
+	{NeedEmbedFiles, "NeedEmbedFiles"},
+	{NeedEmbedPatterns, "NeedEmbedPatterns"},
+	{NeedTarget, "NeedTarget"},
 }
 
-var modeStrings = []string{
-	"NeedName",
-	"NeedFiles",
-	"NeedCompiledGoFiles",
-	"NeedImports",
-	"NeedDeps",
-	"NeedExportFile",
-	"NeedTypes",
-	"NeedSyntax",
-	"NeedTypesInfo",
-	"NeedTypesSizes",
-}
-
-func (mod LoadMode) String() string {
-	m := mod
-	if m == 0 {
+func (mode LoadMode) String() string {
+	if mode == 0 {
 		return "LoadMode(0)"
 	}
 	var out []string
-	for i, x := range allModes {
-		if x > m {
-			break
-		}
-		if (m & x) != 0 {
-			out = append(out, modeStrings[i])
-			m = m ^ x
+	// named bits
+	for _, item := range modes {
+		if (mode & item.mode) != 0 {
+			mode ^= item.mode
+			out = append(out, item.name)
 		}
 	}
-	if m != 0 {
-		out = append(out, "Unknown")
+	// unnamed residue
+	if mode != 0 {
+		if out == nil {
+			return fmt.Sprintf("LoadMode(%#x)", int(mode))
+		}
+		out = append(out, fmt.Sprintf("%#x", int(mode)))
 	}
-	return fmt.Sprintf("LoadMode(%s)", strings.Join(out, "|"))
+	if len(out) == 1 {
+		return out[0]
+	}
+	return "(" + strings.Join(out, "|") + ")"
 }

vendor/golang.org/x/tools/go/packages/packages.go

@@ -16,13 +16,13 @@ import (
 	"go/scanner"
 	"go/token"
 	"go/types"
-	"io"
 	"log"
 	"os"
 	"path/filepath"
 	"runtime"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"golang.org/x/sync/errgroup"
@@ -31,7 +31,6 @@ import (
 	"golang.org/x/tools/internal/gocommand"
 	"golang.org/x/tools/internal/packagesinternal"
 	"golang.org/x/tools/internal/typesinternal"
-	"golang.org/x/tools/internal/versions"
 )
 
 // A LoadMode controls the amount of detail to return when loading.
@@ -44,20 +43,33 @@ import (
 // ID and Errors (if present) will always be filled.
 // [Load] may return more information than requested.
 //
+// The Mode flag is a union of several bits named NeedName,
+// NeedFiles, and so on, each of which determines whether
+// a given field of Package (Name, Files, etc) should be
+// populated.
+//
+// For convenience, we provide named constants for the most
+// common combinations of Need flags:
+//
+//	[LoadFiles]     lists of files in each package
+//	[LoadImports]   ... plus imports
+//	[LoadTypes]     ... plus type information
+//	[LoadSyntax]    ... plus type-annotated syntax
+//	[LoadAllSyntax] ... for all dependencies
+//
 // Unfortunately there are a number of open bugs related to
 // interactions among the LoadMode bits:
-// - https://github.com/golang/go/issues/48226
-// - https://github.com/golang/go/issues/56633
-// - https://github.com/golang/go/issues/56677
-// - https://github.com/golang/go/issues/58726
-// - https://github.com/golang/go/issues/63517
+//   - https://go.dev/issue/56633
+//   - https://go.dev/issue/56677
+//   - https://go.dev/issue/58726
+//   - https://go.dev/issue/63517
 type LoadMode int
 
 const (
 	// NeedName adds Name and PkgPath.
 	NeedName LoadMode = 1 << iota
 
-	// NeedFiles adds GoFiles and OtherFiles.
+	// NeedFiles adds Dir, GoFiles, OtherFiles, and IgnoredFiles
 	NeedFiles
 
 	// NeedCompiledGoFiles adds CompiledGoFiles.
@@ -76,10 +88,10 @@ const (
 	// NeedTypes adds Types, Fset, and IllTyped.
 	NeedTypes
 
-	// NeedSyntax adds Syntax.
+	// NeedSyntax adds Syntax and Fset.
 	NeedSyntax
 
-	// NeedTypesInfo adds TypesInfo.
+	// NeedTypesInfo adds TypesInfo and Fset.
 	NeedTypesInfo
 
 	// NeedTypesSizes adds TypesSizes.
@@ -88,9 +100,10 @@ const (
 	// needInternalDepsErrors adds the internal deps errors field for use by gopls.
 	needInternalDepsErrors
 
-	// needInternalForTest adds the internal forTest field.
+	// NeedForTest adds ForTest.
+	//
 	// Tests must also be set on the context for this field to be populated.
-	needInternalForTest
+	NeedForTest
 
 	// typecheckCgo enables full support for type checking cgo. Requires Go 1.15+.
 	// Modifies CompiledGoFiles and Types, and has no effect on its own.
@@ -104,27 +117,27 @@ const (
 
 	// NeedEmbedPatterns adds EmbedPatterns.
 	NeedEmbedPatterns
+
+	// NeedTarget adds Target.
+	NeedTarget
+
+	// Be sure to update loadmode_string.go when adding new items!
 )
 
 const (
-	// Deprecated: LoadFiles exists for historical compatibility
-	// and should not be used. Please directly specify the needed fields using the Need values.
+	// LoadFiles loads the name and file names for the initial packages.
 	LoadFiles = NeedName | NeedFiles | NeedCompiledGoFiles
 
-	// Deprecated: LoadImports exists for historical compatibility
-	// and should not be used. Please directly specify the needed fields using the Need values.
+	// LoadImports loads the name, file names, and import mapping for the initial packages.
 	LoadImports = LoadFiles | NeedImports
 
-	// Deprecated: LoadTypes exists for historical compatibility
-	// and should not be used. Please directly specify the needed fields using the Need values.
+	// LoadTypes loads exported type information for the initial packages.
 	LoadTypes = LoadImports | NeedTypes | NeedTypesSizes
 
-	// Deprecated: LoadSyntax exists for historical compatibility
-	// and should not be used. Please directly specify the needed fields using the Need values.
+	// LoadSyntax loads typed syntax for the initial packages.
 	LoadSyntax = LoadTypes | NeedSyntax | NeedTypesInfo
 
-	// Deprecated: LoadAllSyntax exists for historical compatibility
-	// and should not be used. Please directly specify the needed fields using the Need values.
+	// LoadAllSyntax loads typed syntax for the initial packages and all dependencies.
 	LoadAllSyntax = LoadSyntax | NeedDeps
 
 	// Deprecated: NeedExportsFile is a historical misspelling of NeedExportFile.
@@ -134,13 +147,7 @@ const (
 // A Config specifies details about how packages should be loaded.
 // The zero value is a valid configuration.
 //
-// Calls to Load do not modify this struct.
-//
-// TODO(adonovan): #67702: this is currently false: in fact,
-// calls to [Load] do not modify the public fields of this struct, but
-// may modify hidden fields, so concurrent calls to [Load] must not
-// use the same Config. But perhaps we should reestablish the
-// documented invariant.
+// Calls to [Load] do not modify this struct.
 type Config struct {
 	// Mode controls the level of information returned for each package.
 	Mode LoadMode
@@ -171,19 +178,10 @@ type Config struct {
 	//
 	Env []string
 
-	// gocmdRunner guards go command calls from concurrency errors.
-	gocmdRunner *gocommand.Runner
-
 	// BuildFlags is a list of command-line flags to be passed through to
 	// the build system's query tool.
 	BuildFlags []string
 
-	// modFile will be used for -modfile in go command invocations.
-	modFile string
-
-	// modFlag will be used for -modfile in go command invocations.
-	modFlag string
-
 	// Fset provides source position information for syntax trees and types.
 	// If Fset is nil, Load will use a new fileset, but preserve Fset's value.
 	Fset *token.FileSet
@@ -230,21 +228,24 @@ type Config struct {
 	// drivers may vary in their level of support for overlays.
 	Overlay map[string][]byte
 
-	// goListOverlayFile is the JSON file that encodes the Overlay
-	// mapping, used by 'go list -overlay=...'
-	goListOverlayFile string
+	// -- Hidden configuration fields only for use in x/tools --
+
+	// modFile will be used for -modfile in go command invocations.
+	modFile string
+
+	// modFlag will be used for -modfile in go command invocations.
+	modFlag string
 }
 
 // Load loads and returns the Go packages named by the given patterns.
 //
-// Config specifies loading options;
-// nil behaves the same as an empty Config.
+// The cfg parameter specifies loading options; nil behaves the same as an empty [Config].
 //
 // The [Config.Mode] field is a set of bits that determine what kinds
 // of information should be computed and returned. Modes that require
 // more information tend to be slower. See [LoadMode] for details
 // and important caveats. Its zero value is equivalent to
-// NeedName | NeedFiles | NeedCompiledGoFiles.
+// [NeedName] | [NeedFiles] | [NeedCompiledGoFiles].
 //
 // Each call to Load returns a new set of [Package] instances.
 // The Packages and their Imports form a directed acyclic graph.
@@ -261,7 +262,7 @@ type Config struct {
 // Errors associated with a particular package are recorded in the
 // corresponding Package's Errors list, and do not cause Load to
 // return an error. Clients may need to handle such errors before
-// proceeding with further analysis. The PrintErrors function is
+// proceeding with further analysis. The [PrintErrors] function is
 // provided for convenient display of all errors.
 func Load(cfg *Config, patterns ...string) ([]*Package, error) {
 	ld := newLoader(cfg)
@@ -324,21 +325,24 @@ func defaultDriver(cfg *Config, patterns ...string) (*DriverResponse, bool, erro
 		} else if !response.NotHandled {
 			return response, true, nil
 		}
-		// (fall through)
+		// not handled: fall through
 	}
 
 	// go list fallback
-	//
+
 	// Write overlays once, as there are many calls
 	// to 'go list' (one per chunk plus others too).
-	overlay, cleanupOverlay, err := gocommand.WriteOverlays(cfg.Overlay)
+	overlayFile, cleanupOverlay, err := gocommand.WriteOverlays(cfg.Overlay)
 	if err != nil {
 		return nil, false, err
 	}
 	defer cleanupOverlay()
-	cfg.goListOverlayFile = overlay
 
-	response, err := callDriverOnChunks(goListDriver, cfg, chunks)
+	var runner gocommand.Runner // (shared across many 'go list' calls)
+	driver := func(cfg *Config, patterns []string) (*DriverResponse, error) {
+		return goListDriver(cfg, &runner, overlayFile, patterns)
+	}
+	response, err := callDriverOnChunks(driver, cfg, chunks)
 	if err != nil {
 		return nil, false, err
 	}
@@ -376,16 +380,14 @@ func splitIntoChunks(patterns []string, argMax int) ([][]string, error) {
 
 func callDriverOnChunks(driver driver, cfg *Config, chunks [][]string) (*DriverResponse, error) {
 	if len(chunks) == 0 {
-		return driver(cfg)
+		return driver(cfg, nil)
 	}
 	responses := make([]*DriverResponse, len(chunks))
 	errNotHandled := errors.New("driver returned NotHandled")
 	var g errgroup.Group
 	for i, chunk := range chunks {
-		i := i
-		chunk := chunk
 		g.Go(func() (err error) {
-			responses[i], err = driver(cfg, chunk...)
+			responses[i], err = driver(cfg, chunk)
 			if responses[i] != nil && responses[i].NotHandled {
 				err = errNotHandled
 			}
@@ -435,6 +437,12 @@ type Package struct {
 	// PkgPath is the package path as used by the go/types package.
 	PkgPath string
 
+	// Dir is the directory associated with the package, if it exists.
+	//
+	// For packages listed by the go command, this is the directory containing
+	// the package files.
+	Dir string
+
 	// Errors contains any errors encountered querying the metadata
 	// of the package, or while parsing or type-checking its files.
 	Errors []Error
@@ -474,6 +482,10 @@ type Package struct {
 	// information for the package as provided by the build system.
 	ExportFile string
 
+	// Target is the absolute install path of the .a file, for libraries,
+	// and of the executable file, for binaries.
+	Target string
+
 	// Imports maps import paths appearing in the package's Go source files
 	// to corresponding loaded Packages.
 	Imports map[string]*Package
@@ -522,8 +534,8 @@ type Package struct {
 
 	// -- internal --
 
-	// forTest is the package under test, if any.
-	forTest string
+	// ForTest is the package under test, if any.
+	ForTest string
 
 	// depsErrors is the DepsErrors field from the go list response, if any.
 	depsErrors []*packagesinternal.PackageError
@@ -552,9 +564,6 @@ type ModuleError struct {
 }
 
 func init() {
-	packagesinternal.GetForTest = func(p interface{}) string {
-		return p.(*Package).forTest
-	}
 	packagesinternal.GetDepsErrors = func(p interface{}) []*packagesinternal.PackageError {
 		return p.(*Package).depsErrors
 	}
@@ -566,7 +575,6 @@ func init() {
 	}
 	packagesinternal.TypecheckCgo = int(typecheckCgo)
 	packagesinternal.DepsErrors = int(needInternalDepsErrors)
-	packagesinternal.ForTest = int(needInternalForTest)
 }
 
 // An Error describes a problem with a package's metadata, syntax, or types.
@@ -682,18 +690,19 @@ func (p *Package) String() string { return p.ID }
 // loaderPackage augments Package with state used during the loading phase
 type loaderPackage struct {
 	*Package
-	importErrors map[string]error // maps each bad import to its error
-	loadOnce     sync.Once
-	color        uint8 // for cycle detection
-	needsrc      bool  // load from source (Mode >= LoadTypes)
-	needtypes    bool  // type information is either requested or depended on
-	initial      bool  // package was matched by a pattern
-	goVersion    int   // minor version number of go command on PATH
+	importErrors    map[string]error // maps each bad import to its error
+	preds           []*loaderPackage // packages that import this one
+	unfinishedSuccs atomic.Int32     // number of direct imports not yet loaded
+	color           uint8            // for cycle detection
+	needsrc         bool             // load from source (Mode >= LoadTypes)
+	needtypes       bool             // type information is either requested or depended on
+	initial         bool             // package was matched by a pattern
+	goVersion       int              // minor version number of go command on PATH
 }
 
 // loader holds the working state of a single call to load.
 type loader struct {
-	pkgs map[string]*loaderPackage
+	pkgs map[string]*loaderPackage // keyed by Package.ID
 	Config
 	sizes        types.Sizes // non-nil if needed by mode
 	parseCache   map[string]*parseValue
@@ -739,9 +748,6 @@ func newLoader(cfg *Config) *loader {
 	if ld.Config.Env == nil {
 		ld.Config.Env = os.Environ()
 	}
-	if ld.Config.gocmdRunner == nil {
-		ld.Config.gocmdRunner = &gocommand.Runner{}
-	}
 	if ld.Context == nil {
 		ld.Context = context.Background()
 	}
@@ -755,7 +761,7 @@ func newLoader(cfg *Config) *loader {
 	ld.requestedMode = ld.Mode
 	ld.Mode = impliedLoadMode(ld.Mode)
 
-	if ld.Mode&NeedTypes != 0 || ld.Mode&NeedSyntax != 0 {
+	if ld.Mode&(NeedSyntax|NeedTypes|NeedTypesInfo) != 0 {
 		if ld.Fset == nil {
 			ld.Fset = token.NewFileSet()
 		}
@@ -764,6 +770,7 @@ func newLoader(cfg *Config) *loader {
 		// because we load source if export data is missing.
 		if ld.ParseFile == nil {
 			ld.ParseFile = func(fset *token.FileSet, filename string, src []byte) (*ast.File, error) {
+				// We implicitly promise to keep doing ast.Object resolution. :(
 				const mode = parser.AllErrors | parser.ParseComments
 				return parser.ParseFile(fset, filename, src, mode)
 			}
@@ -795,7 +802,7 @@ func (ld *loader) refine(response *DriverResponse) ([]*Package, error) {
 		exportDataInvalid := len(ld.Overlay) > 0 || pkg.ExportFile == "" && pkg.PkgPath != "unsafe"
 		// This package needs type information if the caller requested types and the package is
 		// either a root, or it's a non-root and the user requested dependencies ...
-		needtypes := (ld.Mode&NeedTypes|NeedTypesInfo != 0 && (rootIndex >= 0 || ld.Mode&NeedDeps != 0))
+		needtypes := (ld.Mode&(NeedTypes|NeedTypesInfo) != 0 && (rootIndex >= 0 || ld.Mode&NeedDeps != 0))
 		// This package needs source if the call requested source (or types info, which implies source)
 		// and the package is either a root, or itas a non- root and the user requested dependencies...
 		needsrc := ((ld.Mode&(NeedSyntax|NeedTypesInfo) != 0 && (rootIndex >= 0 || ld.Mode&NeedDeps != 0)) ||
@@ -820,9 +827,10 @@ func (ld *loader) refine(response *DriverResponse) ([]*Package, error) {
 		}
 	}
 
-	if ld.Mode&NeedImports != 0 {
-		// Materialize the import graph.
-
+	// Materialize the import graph if it is needed (NeedImports),
+	// or if we'll be using loadPackages (Need{Syntax|Types|TypesInfo}).
+	var leaves []*loaderPackage // packages with no unfinished successors
+	if ld.Mode&(NeedImports|NeedSyntax|NeedTypes|NeedTypesInfo) != 0 {
 		const (
 			white = 0 // new
 			grey  = 1 // in progress
@@ -841,63 +849,76 @@ func (ld *loader) refine(response *DriverResponse) ([]*Package, error) {
 		// dependency on a package that does. These are the only packages
 		// for which we load source code.
 		var stack []*loaderPackage
-		var visit func(lpkg *loaderPackage) bool
-		visit = func(lpkg *loaderPackage) bool {
-			switch lpkg.color {
-			case black:
-				return lpkg.needsrc
-			case grey:
+		var visit func(from, lpkg *loaderPackage) bool
+		visit = func(from, lpkg *loaderPackage) bool {
+			if lpkg.color == grey {
 				panic("internal error: grey node")
 			}
-			lpkg.color = grey
-			stack = append(stack, lpkg) // push
-			stubs := lpkg.Imports       // the structure form has only stubs with the ID in the Imports
-			lpkg.Imports = make(map[string]*Package, len(stubs))
-			for importPath, ipkg := range stubs {
-				var importErr error
-				imp := ld.pkgs[ipkg.ID]
-				if imp == nil {
-					// (includes package "C" when DisableCgo)
-					importErr = fmt.Errorf("missing package: %q", ipkg.ID)
-				} else if imp.color == grey {
-					importErr = fmt.Errorf("import cycle: %s", stack)
-				}
-				if importErr != nil {
-					if lpkg.importErrors == nil {
-						lpkg.importErrors = make(map[string]error)
+			if lpkg.color == white {
+				lpkg.color = grey
+				stack = append(stack, lpkg) // push
+				stubs := lpkg.Imports       // the structure form has only stubs with the ID in the Imports
+				lpkg.Imports = make(map[string]*Package, len(stubs))
+				for importPath, ipkg := range stubs {
+					var importErr error
+					imp := ld.pkgs[ipkg.ID]
+					if imp == nil {
+						// (includes package "C" when DisableCgo)
+						importErr = fmt.Errorf("missing package: %q", ipkg.ID)
+					} else if imp.color == grey {
+						importErr = fmt.Errorf("import cycle: %s", stack)
 					}
-					lpkg.importErrors[importPath] = importErr
-					continue
+					if importErr != nil {
+						if lpkg.importErrors == nil {
+							lpkg.importErrors = make(map[string]error)
+						}
+						lpkg.importErrors[importPath] = importErr
+						continue
+					}
+
+					if visit(lpkg, imp) {
+						lpkg.needsrc = true
+					}
+					lpkg.Imports[importPath] = imp.Package
 				}
 
-				if visit(imp) {
-					lpkg.needsrc = true
+				// -- postorder --
+
+				// Complete type information is required for the
+				// immediate dependencies of each source package.
+				if lpkg.needsrc && ld.Mode&NeedTypes != 0 {
+					for _, ipkg := range lpkg.Imports {
+						ld.pkgs[ipkg.ID].needtypes = true
+					}
 				}
-				lpkg.Imports[importPath] = imp.Package
+
+				// NeedTypeSizes causes TypeSizes to be set even
+				// on packages for which types aren't needed.
+				if ld.Mode&NeedTypesSizes != 0 {
+					lpkg.TypesSizes = ld.sizes
+				}
+
+				// Add packages with no imports directly to the queue of leaves.
+				if len(lpkg.Imports) == 0 {
+					leaves = append(leaves, lpkg)
+				}
+
+				stack = stack[:len(stack)-1] // pop
+				lpkg.color = black
 			}
 
-			// Complete type information is required for the
-			// immediate dependencies of each source package.
-			if lpkg.needsrc && ld.Mode&NeedTypes != 0 {
-				for _, ipkg := range lpkg.Imports {
-					ld.pkgs[ipkg.ID].needtypes = true
-				}
+			// Add edge from predecessor.
+			if from != nil {
+				from.unfinishedSuccs.Add(+1) // incref
+				lpkg.preds = append(lpkg.preds, from)
 			}
 
-			// NeedTypeSizes causes TypeSizes to be set even
-			// on packages for which types aren't needed.
-			if ld.Mode&NeedTypesSizes != 0 {
-				lpkg.TypesSizes = ld.sizes
-			}
-			stack = stack[:len(stack)-1] // pop
-			lpkg.color = black
-
 			return lpkg.needsrc
 		}
 
 		// For each initial package, create its import DAG.
 		for _, lpkg := range initial {
-			visit(lpkg)
+			visit(nil, lpkg)
 		}
 
 	} else {
@@ -910,16 +931,45 @@ func (ld *loader) refine(response *DriverResponse) ([]*Package, error) {
 
 	// Load type data and syntax if needed, starting at
 	// the initial packages (roots of the import DAG).
-	if ld.Mode&NeedTypes != 0 || ld.Mode&NeedSyntax != 0 {
-		var wg sync.WaitGroup
-		for _, lpkg := range initial {
-			wg.Add(1)
-			go func(lpkg *loaderPackage) {
-				ld.loadRecursive(lpkg)
-				wg.Done()
-			}(lpkg)
+	if ld.Mode&(NeedSyntax|NeedTypes|NeedTypesInfo) != 0 {
+
+		// We avoid using g.SetLimit to limit concurrency as
+		// it makes g.Go stop accepting work, which prevents
+		// workers from enqeuing, and thus finishing, and thus
+		// allowing the group to make progress: deadlock.
+		//
+		// Instead we use the ioLimit and cpuLimit semaphores.
+		g, _ := errgroup.WithContext(ld.Context)
+
+		// enqueues adds a package to the type-checking queue.
+		// It must have no unfinished successors.
+		var enqueue func(*loaderPackage)
+		enqueue = func(lpkg *loaderPackage) {
+			g.Go(func() error {
+				// Parse and type-check.
+				ld.loadPackage(lpkg)
+
+				// Notify each waiting predecessor,
+				// and enqueue it when it becomes a leaf.
+				for _, pred := range lpkg.preds {
+					if pred.unfinishedSuccs.Add(-1) == 0 { // decref
+						enqueue(pred)
+					}
+				}
+
+				return nil
+			})
+		}
+
+		// Load leaves first, adding new packages
+		// to the queue as they become leaves.
+		for _, leaf := range leaves {
+			enqueue(leaf)
+		}
+
+		if err := g.Wait(); err != nil {
+			return nil, err // cancelled
 		}
-		wg.Wait()
 	}
 
 	// If the context is done, return its error and
@@ -961,12 +1011,14 @@ func (ld *loader) refine(response *DriverResponse) ([]*Package, error) {
 		}
 		if ld.requestedMode&NeedTypes == 0 {
 			ld.pkgs[i].Types = nil
-			ld.pkgs[i].Fset = nil
 			ld.pkgs[i].IllTyped = false
 		}
 		if ld.requestedMode&NeedSyntax == 0 {
 			ld.pkgs[i].Syntax = nil
 		}
+		if ld.requestedMode&(NeedSyntax|NeedTypes|NeedTypesInfo) == 0 {
+			ld.pkgs[i].Fset = nil
+		}
 		if ld.requestedMode&NeedTypesInfo == 0 {
 			ld.pkgs[i].TypesInfo = nil
 		}
@@ -981,31 +1033,10 @@ func (ld *loader) refine(response *DriverResponse) ([]*Package, error) {
 	return result, nil
 }
 
-// loadRecursive loads the specified package and its dependencies,
-// recursively, in parallel, in topological order.
-// It is atomic and idempotent.
-// Precondition: ld.Mode&NeedTypes.
-func (ld *loader) loadRecursive(lpkg *loaderPackage) {
-	lpkg.loadOnce.Do(func() {
-		// Load the direct dependencies, in parallel.
-		var wg sync.WaitGroup
-		for _, ipkg := range lpkg.Imports {
-			imp := ld.pkgs[ipkg.ID]
-			wg.Add(1)
-			go func(imp *loaderPackage) {
-				ld.loadRecursive(imp)
-				wg.Done()
-			}(imp)
-		}
-		wg.Wait()
-		ld.loadPackage(lpkg)
-	})
-}
-
-// loadPackage loads the specified package.
+// loadPackage loads/parses/typechecks the specified package.
 // It must be called only once per Package,
 // after immediate dependencies are loaded.
-// Precondition: ld.Mode & NeedTypes.
+// Precondition: ld.Mode&(NeedSyntax|NeedTypes|NeedTypesInfo) != 0.
 func (ld *loader) loadPackage(lpkg *loaderPackage) {
 	if lpkg.PkgPath == "unsafe" {
 		// Fill in the blanks to avoid surprises.
@@ -1041,6 +1072,10 @@ func (ld *loader) loadPackage(lpkg *loaderPackage) {
 	if !lpkg.needtypes && !lpkg.needsrc {
 		return
 	}
+
+	// TODO(adonovan): this condition looks wrong:
+	// I think it should be lpkg.needtypes && !lpg.needsrc,
+	// so that NeedSyntax without NeedTypes can be satisfied by export data.
 	if !lpkg.needsrc {
 		if err := ld.loadFromExportData(lpkg); err != nil {
 			lpkg.Errors = append(lpkg.Errors, Error{
@@ -1146,7 +1181,7 @@ func (ld *loader) loadPackage(lpkg *loaderPackage) {
 	}
 
 	lpkg.Syntax = files
-	if ld.Config.Mode&NeedTypes == 0 {
+	if ld.Config.Mode&(NeedTypes|NeedTypesInfo) == 0 {
 		return
 	}
 
@@ -1157,16 +1192,20 @@ func (ld *loader) loadPackage(lpkg *loaderPackage) {
 		return
 	}
 
-	lpkg.TypesInfo = &types.Info{
-		Types:      make(map[ast.Expr]types.TypeAndValue),
-		Defs:       make(map[*ast.Ident]types.Object),
-		Uses:       make(map[*ast.Ident]types.Object),
-		Implicits:  make(map[ast.Node]types.Object),
-		Instances:  make(map[*ast.Ident]types.Instance),
-		Scopes:     make(map[ast.Node]*types.Scope),
-		Selections: make(map[*ast.SelectorExpr]*types.Selection),
+	// Populate TypesInfo only if needed, as it
+	// causes the type checker to work much harder.
+	if ld.Config.Mode&NeedTypesInfo != 0 {
+		lpkg.TypesInfo = &types.Info{
+			Types:        make(map[ast.Expr]types.TypeAndValue),
+			Defs:         make(map[*ast.Ident]types.Object),
+			Uses:         make(map[*ast.Ident]types.Object),
+			Implicits:    make(map[ast.Node]types.Object),
+			Instances:    make(map[*ast.Ident]types.Instance),
+			Scopes:       make(map[ast.Node]*types.Scope),
+			Selections:   make(map[*ast.SelectorExpr]*types.Selection),
+			FileVersions: make(map[*ast.File]string),
+		}
 	}
-	versions.InitFileVersions(lpkg.TypesInfo)
 	lpkg.TypesSizes = ld.sizes
 
 	importer := importerFunc(func(path string) (*types.Package, error) {
@@ -1219,6 +1258,10 @@ func (ld *loader) loadPackage(lpkg *loaderPackage) {
 		}
 	}
 
+	// Type-checking is CPU intensive.
+	cpuLimit <- unit{}            // acquire a token
+	defer func() { <-cpuLimit }() // release a token
+
 	typErr := types.NewChecker(tc, ld.Fset, lpkg.Types, lpkg.TypesInfo).Files(lpkg.Syntax)
 	lpkg.importErrors = nil // no longer needed
 
@@ -1283,8 +1326,11 @@ type importerFunc func(path string) (*types.Package, error)
 func (f importerFunc) Import(path string) (*types.Package, error) { return f(path) }
 
 // We use a counting semaphore to limit
-// the number of parallel I/O calls per process.
-var ioLimit = make(chan bool, 20)
+// the number of parallel I/O calls or CPU threads per process.
+var (
+	ioLimit  = make(chan unit, 20)
+	cpuLimit = make(chan unit, runtime.GOMAXPROCS(0))
+)
 
 func (ld *loader) parseFile(filename string) (*ast.File, error) {
 	ld.parseCacheMu.Lock()
@@ -1301,20 +1347,28 @@ func (ld *loader) parseFile(filename string) (*ast.File, error) {
 
 		var src []byte
 		for f, contents := range ld.Config.Overlay {
+			// TODO(adonovan): Inefficient for large overlays.
+			// Do an exact name-based map lookup
+			// (for nonexistent files) followed by a
+			// FileID-based map lookup (for existing ones).
 			if sameFile(f, filename) {
 				src = contents
+				break
 			}
 		}
 		var err error
 		if src == nil {
-			ioLimit <- true // wait
+			ioLimit <- unit{} // acquire a token
 			src, err = os.ReadFile(filename)
-			<-ioLimit // signal
+			<-ioLimit // release a token
 		}
 		if err != nil {
 			v.err = err
 		} else {
+			// Parsing is CPU intensive.
+			cpuLimit <- unit{} // acquire a token
 			v.f, v.err = ld.ParseFile(ld.Fset, filename, src)
+			<-cpuLimit // release a token
 		}
 
 		close(v.ready)
@@ -1329,18 +1383,21 @@ func (ld *loader) parseFile(filename string) (*ast.File, error) {
 // Because files are scanned in parallel, the token.Pos
 // positions of the resulting ast.Files are not ordered.
 func (ld *loader) parseFiles(filenames []string) ([]*ast.File, []error) {
-	var wg sync.WaitGroup
-	n := len(filenames)
-	parsed := make([]*ast.File, n)
-	errors := make([]error, n)
-	for i, file := range filenames {
-		wg.Add(1)
-		go func(i int, filename string) {
+	var (
+		n      = len(filenames)
+		parsed = make([]*ast.File, n)
+		errors = make([]error, n)
+	)
+	var g errgroup.Group
+	for i, filename := range filenames {
+		// This creates goroutines unnecessarily in the
+		// cache-hit case, but that case is uncommon.
+		g.Go(func() error {
 			parsed[i], errors[i] = ld.parseFile(filename)
-			wg.Done()
-		}(i, file)
+			return nil
+		})
 	}
-	wg.Wait()
+	g.Wait()
 
 	// Eliminate nils, preserving order.
 	var o int
@@ -1499,6 +1556,10 @@ func impliedLoadMode(loadMode LoadMode) LoadMode {
 		// All these things require knowing the import graph.
 		loadMode |= NeedImports
 	}
+	if loadMode&NeedTypes != 0 {
+		// Types require the GoVersion from Module.
+		loadMode |= NeedModule
+	}
 
 	return loadMode
 }
@@ -1507,4 +1568,4 @@ func usesExportData(cfg *Config) bool {
 	return cfg.Mode&NeedExportFile != 0 || cfg.Mode&NeedTypes != 0 && cfg.Mode&NeedDeps == 0
 }
 
-var _ interface{} = io.Discard // assert build toolchain is go1.16 or later
+type unit struct{}

vendor/golang.org/x/tools/go/packages/visit.go

@@ -49,11 +49,20 @@ func Visit(pkgs []*Package, pre func(*Package) bool, post func(*Package)) {
 // PrintErrors returns the number of errors printed.
 func PrintErrors(pkgs []*Package) int {
 	var n int
+	errModules := make(map[*Module]bool)
 	Visit(pkgs, nil, func(pkg *Package) {
 		for _, err := range pkg.Errors {
 			fmt.Fprintln(os.Stderr, err)
 			n++
 		}
+
+		// Print pkg.Module.Error once if present.
+		mod := pkg.Module
+		if mod != nil && mod.Error != nil && !errModules[mod] {
+			errModules[mod] = true
+			fmt.Fprintln(os.Stderr, mod.Error.Err)
+			n++
+		}
 	})
 	return n
 }

vendor/golang.org/x/tools/go/types/objectpath/objectpath.go

@@ -51,7 +51,7 @@ type Path string
 //
 //	PO package->object	Package.Scope.Lookup
 //	OT  object->type 	Object.Type
-//	TT    type->type 	Type.{Elem,Key,Params,Results,Underlying} [EKPRU]
+//	TT    type->type 	Type.{Elem,Key,{,{,Recv}Type}Params,Results,Underlying,Rhs} [EKPRUTrCa]
 //	TO   type->object	Type.{At,Field,Method,Obj} [AFMO]
 //
 // All valid paths start with a package and end at an object
@@ -63,8 +63,8 @@ type Path string
 //   - The only PO operator is Package.Scope.Lookup, which requires an identifier.
 //   - The only OT operator is Object.Type,
 //     which we encode as '.' because dot cannot appear in an identifier.
-//   - The TT operators are encoded as [EKPRUTC];
-//     one of these (TypeParam) requires an integer operand,
+//   - The TT operators are encoded as [EKPRUTrCa];
+//     two of these ({,Recv}TypeParams) require an integer operand,
 //     which is encoded as a string of decimal digits.
 //   - The TO operators are encoded as [AFMO];
 //     three of these (At,Field,Method) require an integer operand,
@@ -98,19 +98,21 @@ const (
 	opType = '.' // .Type()		  (Object)
 
 	// type->type operators
-	opElem       = 'E' // .Elem()		        (Pointer, Slice, Array, Chan, Map)
-	opKey        = 'K' // .Key()		        (Map)
-	opParams     = 'P' // .Params()		      (Signature)
-	opResults    = 'R' // .Results()	      (Signature)
-	opUnderlying = 'U' // .Underlying()	    (Named)
-	opTypeParam  = 'T' // .TypeParams.At(i) (Named, Signature)
-	opConstraint = 'C' // .Constraint()     (TypeParam)
+	opElem          = 'E' // .Elem()		(Pointer, Slice, Array, Chan, Map)
+	opKey           = 'K' // .Key()			(Map)
+	opParams        = 'P' // .Params()		(Signature)
+	opResults       = 'R' // .Results()		(Signature)
+	opUnderlying    = 'U' // .Underlying()		(Named)
+	opTypeParam     = 'T' // .TypeParams.At(i)	(Named, Signature)
+	opRecvTypeParam = 'r' // .RecvTypeParams.At(i)	(Signature)
+	opConstraint    = 'C' // .Constraint()		(TypeParam)
+	opRhs           = 'a' // .Rhs()			(Alias)
 
 	// type->object operators
-	opAt     = 'A' // .At(i)		 (Tuple)
-	opField  = 'F' // .Field(i)	 (Struct)
-	opMethod = 'M' // .Method(i) (Named or Interface; not Struct: "promoted" names are ignored)
-	opObj    = 'O' // .Obj()		 (Named, TypeParam)
+	opAt     = 'A' // .At(i)	(Tuple)
+	opField  = 'F' // .Field(i)	(Struct)
+	opMethod = 'M' // .Method(i)	(Named or Interface; not Struct: "promoted" names are ignored)
+	opObj    = 'O' // .Obj()	(Named, TypeParam)
 )
 
 // For is equivalent to new(Encoder).For(obj).
@@ -226,7 +228,7 @@ func (enc *Encoder) For(obj types.Object) (Path, error) {
 	//    Reject obviously non-viable cases.
 	switch obj := obj.(type) {
 	case *types.TypeName:
-		if _, ok := aliases.Unalias(obj.Type()).(*types.TypeParam); !ok {
+		if _, ok := types.Unalias(obj.Type()).(*types.TypeParam); !ok {
 			// With the exception of type parameters, only package-level type names
 			// have a path.
 			return "", fmt.Errorf("no path for %v", obj)
@@ -278,21 +280,26 @@ func (enc *Encoder) For(obj types.Object) (Path, error) {
 		path = append(path, opType)
 
 		T := o.Type()
-
-		if tname.IsAlias() {
-			// type alias
-			if r := find(obj, T, path, nil); r != nil {
+		if alias, ok := T.(*types.Alias); ok {
+			if r := findTypeParam(obj, aliases.TypeParams(alias), path, opTypeParam); r != nil {
 				return Path(r), nil
 			}
-		} else {
-			if named, _ := T.(*types.Named); named != nil {
-				if r := findTypeParam(obj, named.TypeParams(), path, nil); r != nil {
-					// generic named type
-					return Path(r), nil
-				}
+			if r := find(obj, aliases.Rhs(alias), append(path, opRhs)); r != nil {
+				return Path(r), nil
 			}
+
+		} else if tname.IsAlias() {
+			// legacy alias
+			if r := find(obj, T, path); r != nil {
+				return Path(r), nil
+			}
+
+		} else if named, ok := T.(*types.Named); ok {
 			// defined (named) type
-			if r := find(obj, T.Underlying(), append(path, opUnderlying), nil); r != nil {
+			if r := findTypeParam(obj, named.TypeParams(), path, opTypeParam); r != nil {
+				return Path(r), nil
+			}
+			if r := find(obj, named.Underlying(), append(path, opUnderlying)); r != nil {
 				return Path(r), nil
 			}
 		}
@@ -305,7 +312,7 @@ func (enc *Encoder) For(obj types.Object) (Path, error) {
 		if _, ok := o.(*types.TypeName); !ok {
 			if o.Exported() {
 				// exported non-type (const, var, func)
-				if r := find(obj, o.Type(), append(path, opType), nil); r != nil {
+				if r := find(obj, o.Type(), append(path, opType)); r != nil {
 					return Path(r), nil
 				}
 			}
@@ -313,7 +320,7 @@ func (enc *Encoder) For(obj types.Object) (Path, error) {
 		}
 
 		// Inspect declared methods of defined types.
-		if T, ok := aliases.Unalias(o.Type()).(*types.Named); ok {
+		if T, ok := types.Unalias(o.Type()).(*types.Named); ok {
 			path = append(path, opType)
 			// The method index here is always with respect
 			// to the underlying go/types data structures,
@@ -325,7 +332,7 @@ func (enc *Encoder) For(obj types.Object) (Path, error) {
 				if m == obj {
 					return Path(path2), nil // found declared method
 				}
-				if r := find(obj, m.Type(), append(path2, opType), nil); r != nil {
+				if r := find(obj, m.Type(), append(path2, opType)); r != nil {
 					return Path(r), nil
 				}
 			}
@@ -440,43 +447,64 @@ func (enc *Encoder) concreteMethod(meth *types.Func) (Path, bool) {
 //
 // The seen map is used to short circuit cycles through type parameters. If
 // nil, it will be allocated as necessary.
-func find(obj types.Object, T types.Type, path []byte, seen map[*types.TypeName]bool) []byte {
+//
+// The seenMethods map is used internally to short circuit cycles through
+// interface methods, such as occur in the following example:
+//
+//	type I interface { f() interface{I} }
+//
+// See golang/go#68046 for details.
+func find(obj types.Object, T types.Type, path []byte) []byte {
+	return (&finder{obj: obj}).find(T, path)
+}
+
+// finder closes over search state for a call to find.
+type finder struct {
+	obj             types.Object             // the sought object
+	seenTParamNames map[*types.TypeName]bool // for cycle breaking through type parameters
+	seenMethods     map[*types.Func]bool     // for cycle breaking through recursive interfaces
+}
+
+func (f *finder) find(T types.Type, path []byte) []byte {
 	switch T := T.(type) {
-	case *aliases.Alias:
-		return find(obj, aliases.Unalias(T), path, seen)
+	case *types.Alias:
+		return f.find(types.Unalias(T), path)
 	case *types.Basic, *types.Named:
 		// Named types belonging to pkg were handled already,
 		// so T must belong to another package. No path.
 		return nil
 	case *types.Pointer:
-		return find(obj, T.Elem(), append(path, opElem), seen)
+		return f.find(T.Elem(), append(path, opElem))
 	case *types.Slice:
-		return find(obj, T.Elem(), append(path, opElem), seen)
+		return f.find(T.Elem(), append(path, opElem))
 	case *types.Array:
-		return find(obj, T.Elem(), append(path, opElem), seen)
+		return f.find(T.Elem(), append(path, opElem))
 	case *types.Chan:
-		return find(obj, T.Elem(), append(path, opElem), seen)
+		return f.find(T.Elem(), append(path, opElem))
 	case *types.Map:
-		if r := find(obj, T.Key(), append(path, opKey), seen); r != nil {
+		if r := f.find(T.Key(), append(path, opKey)); r != nil {
 			return r
 		}
-		return find(obj, T.Elem(), append(path, opElem), seen)
+		return f.find(T.Elem(), append(path, opElem))
 	case *types.Signature:
-		if r := findTypeParam(obj, T.TypeParams(), path, seen); r != nil {
+		if r := f.findTypeParam(T.RecvTypeParams(), path, opRecvTypeParam); r != nil {
 			return r
 		}
-		if r := find(obj, T.Params(), append(path, opParams), seen); r != nil {
+		if r := f.findTypeParam(T.TypeParams(), path, opTypeParam); r != nil {
 			return r
 		}
-		return find(obj, T.Results(), append(path, opResults), seen)
+		if r := f.find(T.Params(), append(path, opParams)); r != nil {
+			return r
+		}
+		return f.find(T.Results(), append(path, opResults))
 	case *types.Struct:
 		for i := 0; i < T.NumFields(); i++ {
 			fld := T.Field(i)
 			path2 := appendOpArg(path, opField, i)
-			if fld == obj {
+			if fld == f.obj {
 				return path2 // found field var
 			}
-			if r := find(obj, fld.Type(), append(path2, opType), seen); r != nil {
+			if r := f.find(fld.Type(), append(path2, opType)); r != nil {
 				return r
 			}
 		}
@@ -485,10 +513,10 @@ func find(obj types.Object, T types.Type, path []byte, seen map[*types.TypeName]
 		for i := 0; i < T.Len(); i++ {
 			v := T.At(i)
 			path2 := appendOpArg(path, opAt, i)
-			if v == obj {
+			if v == f.obj {
 				return path2 // found param/result var
 			}
-			if r := find(obj, v.Type(), append(path2, opType), seen); r != nil {
+			if r := f.find(v.Type(), append(path2, opType)); r != nil {
 				return r
 			}
 		}
@@ -496,28 +524,35 @@ func find(obj types.Object, T types.Type, path []byte, seen map[*types.TypeName]
 	case *types.Interface:
 		for i := 0; i < T.NumMethods(); i++ {
 			m := T.Method(i)
+			if f.seenMethods[m] {
+				return nil
+			}
 			path2 := appendOpArg(path, opMethod, i)
-			if m == obj {
+			if m == f.obj {
 				return path2 // found interface method
 			}
-			if r := find(obj, m.Type(), append(path2, opType), seen); r != nil {
+			if f.seenMethods == nil {
+				f.seenMethods = make(map[*types.Func]bool)
+			}
+			f.seenMethods[m] = true
+			if r := f.find(m.Type(), append(path2, opType)); r != nil {
 				return r
 			}
 		}
 		return nil
 	case *types.TypeParam:
 		name := T.Obj()
-		if name == obj {
-			return append(path, opObj)
-		}
-		if seen[name] {
+		if f.seenTParamNames[name] {
 			return nil
 		}
-		if seen == nil {
-			seen = make(map[*types.TypeName]bool)
+		if name == f.obj {
+			return append(path, opObj)
 		}
-		seen[name] = true
-		if r := find(obj, T.Constraint(), append(path, opConstraint), seen); r != nil {
+		if f.seenTParamNames == nil {
+			f.seenTParamNames = make(map[*types.TypeName]bool)
+		}
+		f.seenTParamNames[name] = true
+		if r := f.find(T.Constraint(), append(path, opConstraint)); r != nil {
 			return r
 		}
 		return nil
@@ -525,11 +560,15 @@ func find(obj types.Object, T types.Type, path []byte, seen map[*types.TypeName]
 	panic(T)
 }
 
-func findTypeParam(obj types.Object, list *types.TypeParamList, path []byte, seen map[*types.TypeName]bool) []byte {
+func findTypeParam(obj types.Object, list *types.TypeParamList, path []byte, op byte) []byte {
+	return (&finder{obj: obj}).findTypeParam(list, path, op)
+}
+
+func (f *finder) findTypeParam(list *types.TypeParamList, path []byte, op byte) []byte {
 	for i := 0; i < list.Len(); i++ {
 		tparam := list.At(i)
-		path2 := appendOpArg(path, opTypeParam, i)
-		if r := find(obj, tparam, path2, seen); r != nil {
+		path2 := appendOpArg(path, op, i)
+		if r := f.find(tparam, path2); r != nil {
 			return r
 		}
 	}
@@ -580,10 +619,10 @@ func Object(pkg *types.Package, p Path) (types.Object, error) {
 		code := suffix[0]
 		suffix = suffix[1:]
 
-		// Codes [AFM] have an integer operand.
+		// Codes [AFMTr] have an integer operand.
 		var index int
 		switch code {
-		case opAt, opField, opMethod, opTypeParam:
+		case opAt, opField, opMethod, opTypeParam, opRecvTypeParam:
 			rest := strings.TrimLeft(suffix, "0123456789")
 			numerals := suffix[:len(suffix)-len(rest)]
 			suffix = rest
@@ -616,7 +655,7 @@ func Object(pkg *types.Package, p Path) (types.Object, error) {
 
 		// Inv: t != nil, obj == nil
 
-		t = aliases.Unalias(t)
+		t = types.Unalias(t)
 		switch code {
 		case opElem:
 			hasElem, ok := t.(hasElem) // Pointer, Slice, Array, Chan, Map
@@ -653,6 +692,16 @@ func Object(pkg *types.Package, p Path) (types.Object, error) {
 			}
 			t = named.Underlying()
 
+		case opRhs:
+			if alias, ok := t.(*types.Alias); ok {
+				t = aliases.Rhs(alias)
+			} else if false && aliases.Enabled() {
+				// The Enabled check is too expensive, so for now we
+				// simply assume that aliases are not enabled.
+				// TODO(adonovan): replace with "if true {" when go1.24 is assured.
+				return nil, fmt.Errorf("cannot apply %q to %s (got %T, want alias)", code, t, t)
+			}
+
 		case opTypeParam:
 			hasTypeParams, ok := t.(hasTypeParams) // Named, Signature
 			if !ok {
@@ -664,6 +713,17 @@ func Object(pkg *types.Package, p Path) (types.Object, error) {
 			}
 			t = tparams.At(index)
 
+		case opRecvTypeParam:
+			sig, ok := t.(*types.Signature) // Signature
+			if !ok {
+				return nil, fmt.Errorf("cannot apply %q to %s (got %T, want signature)", code, t, t)
+			}
+			rtparams := sig.RecvTypeParams()
+			if n := rtparams.Len(); index >= n {
+				return nil, fmt.Errorf("tuple index %d out of range [0-%d)", index, n)
+			}
+			t = rtparams.At(index)
+
 		case opConstraint:
 			tparam, ok := t.(*types.TypeParam)
 			if !ok {
@@ -725,6 +785,10 @@ func Object(pkg *types.Package, p Path) (types.Object, error) {
 		}
 	}
 
+	if obj == nil {
+		panic(p) // path does not end in an object-valued operator
+	}
+
 	if obj.Pkg() != pkg {
 		return nil, fmt.Errorf("path denotes %s, which belongs to a different package", obj)
 	}

vendor/golang.org/x/tools/go/types/typeutil/callee.go

@@ -0,0 +1,68 @@
+// Copyright 2018 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 typeutil
+
+import (
+	"go/ast"
+	"go/types"
+
+	"golang.org/x/tools/internal/typeparams"
+)
+
+// Callee returns the named target of a function call, if any:
+// a function, method, builtin, or variable.
+//
+// Functions and methods may potentially have type parameters.
+func Callee(info *types.Info, call *ast.CallExpr) types.Object {
+	fun := ast.Unparen(call.Fun)
+
+	// Look through type instantiation if necessary.
+	isInstance := false
+	switch fun.(type) {
+	case *ast.IndexExpr, *ast.IndexListExpr:
+		// When extracting the callee from an *IndexExpr, we need to check that
+		// it is a *types.Func and not a *types.Var.
+		// Example: Don't match a slice m within the expression `m[0]()`.
+		isInstance = true
+		fun, _, _, _ = typeparams.UnpackIndexExpr(fun)
+	}
+
+	var obj types.Object
+	switch fun := fun.(type) {
+	case *ast.Ident:
+		obj = info.Uses[fun] // type, var, builtin, or declared func
+	case *ast.SelectorExpr:
+		if sel, ok := info.Selections[fun]; ok {
+			obj = sel.Obj() // method or field
+		} else {
+			obj = info.Uses[fun.Sel] // qualified identifier?
+		}
+	}
+	if _, ok := obj.(*types.TypeName); ok {
+		return nil // T(x) is a conversion, not a call
+	}
+	// A Func is required to match instantiations.
+	if _, ok := obj.(*types.Func); isInstance && !ok {
+		return nil // Was not a Func.
+	}
+	return obj
+}
+
+// StaticCallee returns the target (function or method) of a static function
+// call, if any. It returns nil for calls to builtins.
+//
+// Note: for calls of instantiated functions and methods, StaticCallee returns
+// the corresponding generic function or method on the generic type.
+func StaticCallee(info *types.Info, call *ast.CallExpr) *types.Func {
+	if f, ok := Callee(info, call).(*types.Func); ok && !interfaceMethod(f) {
+		return f
+	}
+	return nil
+}
+
+func interfaceMethod(f *types.Func) bool {
+	recv := f.Type().(*types.Signature).Recv()
+	return recv != nil && types.IsInterface(recv.Type())
+}

vendor/golang.org/x/tools/go/types/typeutil/imports.go

@@ -0,0 +1,30 @@
+// Copyright 2014 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 typeutil
+
+import "go/types"
+
+// Dependencies returns all dependencies of the specified packages.
+//
+// Dependent packages appear in topological order: if package P imports
+// package Q, Q appears earlier than P in the result.
+// The algorithm follows import statements in the order they
+// appear in the source code, so the result is a total order.
+func Dependencies(pkgs ...*types.Package) []*types.Package {
+	var result []*types.Package
+	seen := make(map[*types.Package]bool)
+	var visit func(pkgs []*types.Package)
+	visit = func(pkgs []*types.Package) {
+		for _, p := range pkgs {
+			if !seen[p] {
+				seen[p] = true
+				visit(p.Imports())
+				result = append(result, p)
+			}
+		}
+	}
+	visit(pkgs)
+	return result
+}

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

@@ -0,0 +1,470 @@
+// Copyright 2014 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 typeutil defines various utilities for types, such as [Map],
+// a hash table that maps [types.Type] to any value.
+package typeutil
+
+import (
+	"bytes"
+	"fmt"
+	"go/types"
+	"hash/maphash"
+	"unsafe"
+
+	"golang.org/x/tools/internal/typeparams"
+)
+
+// Map is a hash-table-based mapping from types (types.Type) to
+// arbitrary 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.
+//
+// Just as with map[K]V, a nil *Map is a valid empty map.
+//
+// Read-only map operations ([Map.At], [Map.Len], and so on) may
+// safely be called concurrently.
+//
+// TODO(adonovan): deprecate in favor of https://go.dev/issues/69420
+// and 69559, if the latter proposals for a generic hash-map type and
+// a types.Hash function are accepted.
+type Map struct {
+	table  map[uint32][]entry // maps hash to bucket; entry.key==nil means unused
+	length int                // number of map entries
+}
+
+// entry is an entry (key/value association) in a hash bucket.
+type entry struct {
+	key   types.Type
+	value any
+}
+
+// SetHasher has no effect.
+//
+// It is a relic of an optimization that is no longer profitable. Do
+// not use [Hasher], [MakeHasher], or [SetHasher] in new code.
+func (m *Map) SetHasher(Hasher) {}
+
+// Delete removes the entry with the given key, if any.
+// It returns true if the entry was found.
+func (m *Map) Delete(key types.Type) bool {
+	if m != nil && m.table != nil {
+		hash := hash(key)
+		bucket := m.table[hash]
+		for i, e := range bucket {
+			if e.key != nil && types.Identical(key, e.key) {
+				// We can't compact the bucket as it
+				// would disturb iterators.
+				bucket[i] = entry{}
+				m.length--
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// 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) any {
+	if m != nil && m.table != nil {
+		for _, e := range m.table[hash(key)] {
+			if e.key != nil && types.Identical(key, e.key) {
+				return e.value
+			}
+		}
+	}
+	return nil
+}
+
+// Set sets the map entry for key to val,
+// and returns the previous entry, if any.
+func (m *Map) Set(key types.Type, value any) (prev any) {
+	if m.table != nil {
+		hash := hash(key)
+		bucket := m.table[hash]
+		var hole *entry
+		for i, e := range bucket {
+			if e.key == nil {
+				hole = &bucket[i]
+			} else if types.Identical(key, e.key) {
+				prev = e.value
+				bucket[i].value = value
+				return
+			}
+		}
+
+		if hole != nil {
+			*hole = entry{key, value} // overwrite deleted entry
+		} else {
+			m.table[hash] = append(bucket, entry{key, value})
+		}
+	} else {
+		hash := hash(key)
+		m.table = map[uint32][]entry{hash: {entry{key, value}}}
+	}
+
+	m.length++
+	return
+}
+
+// Len returns the number of map entries.
+func (m *Map) Len() int {
+	if m != nil {
+		return m.length
+	}
+	return 0
+}
+
+// Iterate calls function f on each entry in the map in unspecified order.
+//
+// If f should mutate the map, Iterate provides the same guarantees as
+// Go maps: if f deletes a map entry that Iterate has not yet reached,
+// 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 any)) {
+	if m != nil {
+		for _, bucket := range m.table {
+			for _, e := range bucket {
+				if e.key != nil {
+					f(e.key, e.value)
+				}
+			}
+		}
+	}
+}
+
+// Keys returns a new slice containing the set of map keys.
+// The order is unspecified.
+func (m *Map) Keys() []types.Type {
+	keys := make([]types.Type, 0, m.Len())
+	m.Iterate(func(key types.Type, _ any) {
+		keys = append(keys, key)
+	})
+	return keys
+}
+
+func (m *Map) toString(values bool) string {
+	if m == nil {
+		return "{}"
+	}
+	var buf bytes.Buffer
+	fmt.Fprint(&buf, "{")
+	sep := ""
+	m.Iterate(func(key types.Type, value any) {
+		fmt.Fprint(&buf, sep)
+		sep = ", "
+		fmt.Fprint(&buf, key)
+		if values {
+			fmt.Fprintf(&buf, ": %q", value)
+		}
+	})
+	fmt.Fprint(&buf, "}")
+	return buf.String()
+}
+
+// String returns a string representation of the map's entries.
+// Values are printed using fmt.Sprintf("%v", v).
+// Order is unspecified.
+func (m *Map) String() string {
+	return m.toString(true)
+}
+
+// KeysString returns a string representation of the map's key set.
+// Order is unspecified.
+func (m *Map) KeysString() string {
+	return m.toString(false)
+}
+
+// -- Hasher --
+
+// hash returns the hash of type t.
+// TODO(adonovan): replace by types.Hash when Go proposal #69420 is accepted.
+func hash(t types.Type) uint32 {
+	return theHasher.Hash(t)
+}
+
+// A Hasher provides a [Hasher.Hash] method to map a type to its hash value.
+// Hashers are stateless, and all are equivalent.
+type Hasher struct{}
+
+var theHasher Hasher
+
+// MakeHasher returns Hasher{}.
+// Hashers are stateless; all are equivalent.
+func MakeHasher() Hasher { return theHasher }
+
+// Hash computes a hash value for the given type t such that
+// Identical(t, t') => Hash(t) == Hash(t').
+func (h Hasher) Hash(t types.Type) uint32 {
+	return hasher{inGenericSig: false}.hash(t)
+}
+
+// hasher holds the state of a single Hash traversal: whether we are
+// inside the signature of a generic function; this is used to
+// optimize [hasher.hashTypeParam].
+type hasher struct{ inGenericSig bool }
+
+// hashString computes the Fowler–Noll–Vo hash of s.
+func hashString(s string) uint32 {
+	var h uint32
+	for i := 0; i < len(s); i++ {
+		h ^= uint32(s[i])
+		h *= 16777619
+	}
+	return h
+}
+
+// hash computes the hash of t.
+func (h hasher) hash(t types.Type) uint32 {
+	// See Identical for rationale.
+	switch t := t.(type) {
+	case *types.Basic:
+		return uint32(t.Kind())
+
+	case *types.Alias:
+		return h.hash(types.Unalias(t))
+
+	case *types.Array:
+		return 9043 + 2*uint32(t.Len()) + 3*h.hash(t.Elem())
+
+	case *types.Slice:
+		return 9049 + 2*h.hash(t.Elem())
+
+	case *types.Struct:
+		var hash uint32 = 9059
+		for i, n := 0, t.NumFields(); i < n; i++ {
+			f := t.Field(i)
+			if f.Anonymous() {
+				hash += 8861
+			}
+			hash += hashString(t.Tag(i))
+			hash += hashString(f.Name()) // (ignore f.Pkg)
+			hash += h.hash(f.Type())
+		}
+		return hash
+
+	case *types.Pointer:
+		return 9067 + 2*h.hash(t.Elem())
+
+	case *types.Signature:
+		var hash uint32 = 9091
+		if t.Variadic() {
+			hash *= 8863
+		}
+
+		tparams := t.TypeParams()
+		if n := tparams.Len(); n > 0 {
+			h.inGenericSig = true // affects constraints, params, and results
+
+			for i := range n {
+				tparam := tparams.At(i)
+				hash += 7 * h.hash(tparam.Constraint())
+			}
+		}
+
+		return hash + 3*h.hashTuple(t.Params()) + 5*h.hashTuple(t.Results())
+
+	case *types.Union:
+		return h.hashUnion(t)
+
+	case *types.Interface:
+		// Interfaces are identical if they have the same set of methods, with
+		// identical names and types, and they have the same set of type
+		// restrictions. See go/types.identical for more details.
+		var hash uint32 = 9103
+
+		// Hash methods.
+		for i, n := 0, t.NumMethods(); i < n; i++ {
+			// Method order is not significant.
+			// Ignore m.Pkg().
+			m := t.Method(i)
+			// Use shallow hash on method signature to
+			// avoid anonymous interface cycles.
+			hash += 3*hashString(m.Name()) + 5*h.shallowHash(m.Type())
+		}
+
+		// Hash type restrictions.
+		terms, err := typeparams.InterfaceTermSet(t)
+		// if err != nil t has invalid type restrictions.
+		if err == nil {
+			hash += h.hashTermSet(terms)
+		}
+
+		return hash
+
+	case *types.Map:
+		return 9109 + 2*h.hash(t.Key()) + 3*h.hash(t.Elem())
+
+	case *types.Chan:
+		return 9127 + 2*uint32(t.Dir()) + 3*h.hash(t.Elem())
+
+	case *types.Named:
+		hash := h.hashTypeName(t.Obj())
+		targs := t.TypeArgs()
+		for i := 0; i < targs.Len(); i++ {
+			targ := targs.At(i)
+			hash += 2 * h.hash(targ)
+		}
+		return hash
+
+	case *types.TypeParam:
+		return h.hashTypeParam(t)
+
+	case *types.Tuple:
+		return h.hashTuple(t)
+	}
+
+	panic(fmt.Sprintf("%T: %v", t, t))
+}
+
+func (h hasher) hashTuple(tuple *types.Tuple) uint32 {
+	// See go/types.identicalTypes for rationale.
+	n := tuple.Len()
+	hash := 9137 + 2*uint32(n)
+	for i := range n {
+		hash += 3 * h.hash(tuple.At(i).Type())
+	}
+	return hash
+}
+
+func (h hasher) hashUnion(t *types.Union) uint32 {
+	// Hash type restrictions.
+	terms, err := typeparams.UnionTermSet(t)
+	// if err != nil t has invalid type restrictions. Fall back on a non-zero
+	// hash.
+	if err != nil {
+		return 9151
+	}
+	return h.hashTermSet(terms)
+}
+
+func (h hasher) hashTermSet(terms []*types.Term) uint32 {
+	hash := 9157 + 2*uint32(len(terms))
+	for _, term := range terms {
+		// term order is not significant.
+		termHash := h.hash(term.Type())
+		if term.Tilde() {
+			termHash *= 9161
+		}
+		hash += 3 * termHash
+	}
+	return hash
+}
+
+// hashTypeParam returns the hash of a type parameter.
+func (h hasher) hashTypeParam(t *types.TypeParam) uint32 {
+	// Within the signature of a generic function, TypeParams are
+	// identical if they have the same index and constraint, so we
+	// hash them based on index.
+	//
+	// When we are outside a generic function, free TypeParams are
+	// identical iff they are the same object, so we can use a
+	// more discriminating hash consistent with object identity.
+	// This optimization saves [Map] about 4% when hashing all the
+	// types.Info.Types in the forward closure of net/http.
+	if !h.inGenericSig {
+		// Optimization: outside a generic function signature,
+		// use a more discrimating hash consistent with object identity.
+		return h.hashTypeName(t.Obj())
+	}
+	return 9173 + 3*uint32(t.Index())
+}
+
+var theSeed = maphash.MakeSeed()
+
+// hashTypeName hashes the pointer of tname.
+func (hasher) hashTypeName(tname *types.TypeName) uint32 {
+	// Since types.Identical uses == to compare TypeNames,
+	// the Hash function uses maphash.Comparable.
+	// TODO(adonovan): or will, when it becomes available in go1.24.
+	// In the meantime we use the pointer's numeric value.
+	//
+	//   hash := maphash.Comparable(theSeed, tname)
+	//
+	// (Another approach would be to hash the name and package
+	// path, and whether or not it is a package-level typename. It
+	// is rare for a package to define multiple local types with
+	// the same name.)
+	hash := uintptr(unsafe.Pointer(tname))
+	return uint32(hash ^ (hash >> 32))
+}
+
+// shallowHash computes a hash of t without looking at any of its
+// element Types, to avoid potential anonymous cycles in the types of
+// interface methods.
+//
+// When an unnamed non-empty interface type appears anywhere among the
+// arguments or results of an interface method, there is a potential
+// for endless recursion. Consider:
+//
+//	type X interface { m() []*interface { X } }
+//
+// The problem is that the Methods of the interface in m's result type
+// include m itself; there is no mention of the named type X that
+// might help us break the cycle.
+// (See comment in go/types.identical, case *Interface, for more.)
+func (h hasher) shallowHash(t types.Type) uint32 {
+	// t is the type of an interface method (Signature),
+	// its params or results (Tuples), or their immediate
+	// elements (mostly Slice, Pointer, Basic, Named),
+	// so there's no need to optimize anything else.
+	switch t := t.(type) {
+	case *types.Alias:
+		return h.shallowHash(types.Unalias(t))
+
+	case *types.Signature:
+		var hash uint32 = 604171
+		if t.Variadic() {
+			hash *= 971767
+		}
+		// The Signature/Tuple recursion is always finite
+		// and invariably shallow.
+		return hash + 1062599*h.shallowHash(t.Params()) + 1282529*h.shallowHash(t.Results())
+
+	case *types.Tuple:
+		n := t.Len()
+		hash := 9137 + 2*uint32(n)
+		for i := range n {
+			hash += 53471161 * h.shallowHash(t.At(i).Type())
+		}
+		return hash
+
+	case *types.Basic:
+		return 45212177 * uint32(t.Kind())
+
+	case *types.Array:
+		return 1524181 + 2*uint32(t.Len())
+
+	case *types.Slice:
+		return 2690201
+
+	case *types.Struct:
+		return 3326489
+
+	case *types.Pointer:
+		return 4393139
+
+	case *types.Union:
+		return 562448657
+
+	case *types.Interface:
+		return 2124679 // no recursion here
+
+	case *types.Map:
+		return 9109
+
+	case *types.Chan:
+		return 9127
+
+	case *types.Named:
+		return h.hashTypeName(t.Obj())
+
+	case *types.TypeParam:
+		return h.hashTypeParam(t)
+	}
+	panic(fmt.Sprintf("shallowHash: %T: %v", t, t))
+}

vendor/golang.org/x/tools/go/types/typeutil/methodsetcache.go

@@ -0,0 +1,71 @@
+// Copyright 2014 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.
+
+// This file implements a cache of method sets.
+
+package typeutil
+
+import (
+	"go/types"
+	"sync"
+)
+
+// A MethodSetCache records the method set of each type T for which
+// MethodSet(T) is called so that repeat queries are fast.
+// The zero value is a ready-to-use cache instance.
+type MethodSetCache struct {
+	mu     sync.Mutex
+	named  map[*types.Named]struct{ value, pointer *types.MethodSet } // method sets for named N and *N
+	others map[types.Type]*types.MethodSet                            // all other types
+}
+
+// MethodSet returns the method set of type T.  It is thread-safe.
+//
+// If cache is nil, this function is equivalent to types.NewMethodSet(T).
+// Utility functions can thus expose an optional *MethodSetCache
+// parameter to clients that care about performance.
+func (cache *MethodSetCache) MethodSet(T types.Type) *types.MethodSet {
+	if cache == nil {
+		return types.NewMethodSet(T)
+	}
+	cache.mu.Lock()
+	defer cache.mu.Unlock()
+
+	switch T := types.Unalias(T).(type) {
+	case *types.Named:
+		return cache.lookupNamed(T).value
+
+	case *types.Pointer:
+		if N, ok := types.Unalias(T.Elem()).(*types.Named); ok {
+			return cache.lookupNamed(N).pointer
+		}
+	}
+
+	// all other types
+	// (The map uses pointer equivalence, not type identity.)
+	mset := cache.others[T]
+	if mset == nil {
+		mset = types.NewMethodSet(T)
+		if cache.others == nil {
+			cache.others = make(map[types.Type]*types.MethodSet)
+		}
+		cache.others[T] = mset
+	}
+	return mset
+}
+
+func (cache *MethodSetCache) lookupNamed(named *types.Named) struct{ value, pointer *types.MethodSet } {
+	if cache.named == nil {
+		cache.named = make(map[*types.Named]struct{ value, pointer *types.MethodSet })
+	}
+	// Avoid recomputing mset(*T) for each distinct Pointer
+	// instance whose underlying type is a named type.
+	msets, ok := cache.named[named]
+	if !ok {
+		msets.value = types.NewMethodSet(named)
+		msets.pointer = types.NewMethodSet(types.NewPointer(named))
+		cache.named[named] = msets
+	}
+	return msets
+}

vendor/golang.org/x/tools/go/types/typeutil/ui.go

@@ -0,0 +1,53 @@
+// Copyright 2014 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 typeutil
+
+// This file defines utilities for user interfaces that display types.
+
+import (
+	"go/types"
+)
+
+// IntuitiveMethodSet returns the intuitive method set of a type T,
+// which is the set of methods you can call on an addressable value of
+// that type.
+//
+// The result always contains MethodSet(T), and is exactly MethodSet(T)
+// for interface types and for pointer-to-concrete types.
+// For all other concrete types T, the result additionally
+// contains each method belonging to *T if there is no identically
+// named method on T itself.
+//
+// This corresponds to user intuition about method sets;
+// this function is intended only for user interfaces.
+//
+// The order of the result is as for types.MethodSet(T).
+func IntuitiveMethodSet(T types.Type, msets *MethodSetCache) []*types.Selection {
+	isPointerToConcrete := func(T types.Type) bool {
+		ptr, ok := types.Unalias(T).(*types.Pointer)
+		return ok && !types.IsInterface(ptr.Elem())
+	}
+
+	var result []*types.Selection
+	mset := msets.MethodSet(T)
+	if types.IsInterface(T) || isPointerToConcrete(T) {
+		for i, n := 0, mset.Len(); i < n; i++ {
+			result = append(result, mset.At(i))
+		}
+	} else {
+		// T is some other concrete type.
+		// Report methods of T and *T, preferring those of T.
+		pmset := msets.MethodSet(types.NewPointer(T))
+		for i, n := 0, pmset.Len(); i < n; i++ {
+			meth := pmset.At(i)
+			if m := mset.Lookup(meth.Obj().Pkg(), meth.Obj().Name()); m != nil {
+				meth = m
+			}
+			result = append(result, meth)
+		}
+
+	}
+	return result
+}