Adding upstream version 1.16.10.upstream/1.16.10upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1284 insertions, 0 deletions

diff --git a/src/go/internal/gccgoimporter/parser.go b/src/go/internal/gccgoimporter/parser.go
new file mode 100644
index 0000000..1b1d07d
--- /dev/null
+++ b/src/go/internal/gccgoimporter/parser.go
@@ -0,0 +1,1284 @@
+// Copyright 2013 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 gccgoimporter
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"go/constant"
+	"go/token"
+	"go/types"
+	"io"
+	"strconv"
+	"strings"
+	"text/scanner"
+	"unicode/utf8"
+)
+
+type parser struct {
+	scanner  *scanner.Scanner
+	version  string                    // format version
+	tok      rune                      // current token
+	lit      string                    // literal string; only valid for Ident, Int, String tokens
+	pkgpath  string                    // package path of imported package
+	pkgname  string                    // name of imported package
+	pkg      *types.Package            // reference to imported package
+	imports  map[string]*types.Package // package path -> package object
+	typeList []types.Type              // type number -> type
+	typeData []string                  // unparsed type data (v3 and later)
+	fixups   []fixupRecord             // fixups to apply at end of parsing
+	initdata InitData                  // package init priority data
+	aliases  map[int]string            // maps saved type number to alias name
+}
+
+// When reading export data it's possible to encounter a defined type
+// N1 with an underlying defined type N2 while we are still reading in
+// that defined type N2; see issues #29006 and #29198 for instances
+// of this. Example:
+//
+//   type N1 N2
+//   type N2 struct {
+//      ...
+//      p *N1
+//   }
+//
+// To handle such cases, the parser generates a fixup record (below) and
+// delays setting of N1's underlying type until parsing is complete, at
+// which point fixups are applied.
+
+type fixupRecord struct {
+	toUpdate *types.Named // type to modify when fixup is processed
+	target   types.Type   // type that was incomplete when fixup was created
+}
+
+func (p *parser) init(filename string, src io.Reader, imports map[string]*types.Package) {
+	p.scanner = new(scanner.Scanner)
+	p.initScanner(filename, src)
+	p.imports = imports
+	p.aliases = make(map[int]string)
+	p.typeList = make([]types.Type, 1 /* type numbers start at 1 */, 16)
+}
+
+func (p *parser) initScanner(filename string, src io.Reader) {
+	p.scanner.Init(src)
+	p.scanner.Error = func(_ *scanner.Scanner, msg string) { p.error(msg) }
+	p.scanner.Mode = scanner.ScanIdents | scanner.ScanInts | scanner.ScanFloats | scanner.ScanStrings
+	p.scanner.Whitespace = 1<<'\t' | 1<<' '
+	p.scanner.Filename = filename // for good error messages
+	p.next()
+}
+
+type importError struct {
+	pos scanner.Position
+	err error
+}
+
+func (e importError) Error() string {
+	return fmt.Sprintf("import error %s (byte offset = %d): %s", e.pos, e.pos.Offset, e.err)
+}
+
+func (p *parser) error(err interface{}) {
+	if s, ok := err.(string); ok {
+		err = errors.New(s)
+	}
+	// panic with a runtime.Error if err is not an error
+	panic(importError{p.scanner.Pos(), err.(error)})
+}
+
+func (p *parser) errorf(format string, args ...interface{}) {
+	p.error(fmt.Errorf(format, args...))
+}
+
+func (p *parser) expect(tok rune) string {
+	lit := p.lit
+	if p.tok != tok {
+		p.errorf("expected %s, got %s (%s)", scanner.TokenString(tok), scanner.TokenString(p.tok), lit)
+	}
+	p.next()
+	return lit
+}
+
+func (p *parser) expectEOL() {
+	if p.version == "v1" || p.version == "v2" {
+		p.expect(';')
+	}
+	p.expect('\n')
+}
+
+func (p *parser) expectKeyword(keyword string) {
+	lit := p.expect(scanner.Ident)
+	if lit != keyword {
+		p.errorf("expected keyword %s, got %q", keyword, lit)
+	}
+}
+
+func (p *parser) parseString() string {
+	str, err := strconv.Unquote(p.expect(scanner.String))
+	if err != nil {
+		p.error(err)
+	}
+	return str
+}
+
+// unquotedString     = { unquotedStringChar } .
+// unquotedStringChar = <neither a whitespace nor a ';' char> .
+func (p *parser) parseUnquotedString() string {
+	if p.tok == scanner.EOF {
+		p.error("unexpected EOF")
+	}
+	var buf bytes.Buffer
+	buf.WriteString(p.scanner.TokenText())
+	// This loop needs to examine each character before deciding whether to consume it. If we see a semicolon,
+	// we need to let it be consumed by p.next().
+	for ch := p.scanner.Peek(); ch != '\n' && ch != ';' && ch != scanner.EOF && p.scanner.Whitespace&(1<<uint(ch)) == 0; ch = p.scanner.Peek() {
+		buf.WriteRune(ch)
+		p.scanner.Next()
+	}
+	p.next()
+	return buf.String()
+}
+
+func (p *parser) next() {
+	p.tok = p.scanner.Scan()
+	switch p.tok {
+	case scanner.Ident, scanner.Int, scanner.Float, scanner.String, '·':
+		p.lit = p.scanner.TokenText()
+	default:
+		p.lit = ""
+	}
+}
+
+func (p *parser) parseQualifiedName() (path, name string) {
+	return p.parseQualifiedNameStr(p.parseString())
+}
+
+func (p *parser) parseUnquotedQualifiedName() (path, name string) {
+	return p.parseQualifiedNameStr(p.parseUnquotedString())
+}
+
+// qualifiedName = [ ["."] unquotedString "." ] unquotedString .
+//
+// The above production uses greedy matching.
+func (p *parser) parseQualifiedNameStr(unquotedName string) (pkgpath, name string) {
+	parts := strings.Split(unquotedName, ".")
+	if parts[0] == "" {
+		parts = parts[1:]
+	}
+
+	switch len(parts) {
+	case 0:
+		p.errorf("malformed qualified name: %q", unquotedName)
+	case 1:
+		// unqualified name
+		pkgpath = p.pkgpath
+		name = parts[0]
+	default:
+		// qualified name, which may contain periods
+		pkgpath = strings.Join(parts[0:len(parts)-1], ".")
+		name = parts[len(parts)-1]
+	}
+
+	return
+}
+
+// getPkg returns the package for a given path. If the package is
+// not found but we have a package name, create the package and
+// add it to the p.imports map.
+//
+func (p *parser) getPkg(pkgpath, name string) *types.Package {
+	// package unsafe is not in the imports map - handle explicitly
+	if pkgpath == "unsafe" {
+		return types.Unsafe
+	}
+	pkg := p.imports[pkgpath]
+	if pkg == nil && name != "" {
+		pkg = types.NewPackage(pkgpath, name)
+		p.imports[pkgpath] = pkg
+	}
+	return pkg
+}
+
+// parseExportedName is like parseQualifiedName, but
+// the package path is resolved to an imported *types.Package.
+//
+// ExportedName = string [string] .
+func (p *parser) parseExportedName() (pkg *types.Package, name string) {
+	path, name := p.parseQualifiedName()
+	var pkgname string
+	if p.tok == scanner.String {
+		pkgname = p.parseString()
+	}
+	pkg = p.getPkg(path, pkgname)
+	if pkg == nil {
+		p.errorf("package %s (path = %q) not found", name, path)
+	}
+	return
+}
+
+// Name = QualifiedName | "?" .
+func (p *parser) parseName() string {
+	if p.tok == '?' {
+		// Anonymous.
+		p.next()
+		return ""
+	}
+	// The package path is redundant for us. Don't try to parse it.
+	_, name := p.parseUnquotedQualifiedName()
+	return name
+}
+
+func deref(typ types.Type) types.Type {
+	if p, _ := typ.(*types.Pointer); p != nil {
+		typ = p.Elem()
+	}
+	return typ
+}
+
+// Field = Name Type [string] .
+func (p *parser) parseField(pkg *types.Package) (field *types.Var, tag string) {
+	name := p.parseName()
+	typ, n := p.parseTypeExtended(pkg)
+	anon := false
+	if name == "" {
+		anon = true
+		// Alias?
+		if aname, ok := p.aliases[n]; ok {
+			name = aname
+		} else {
+			switch typ := deref(typ).(type) {
+			case *types.Basic:
+				name = typ.Name()
+			case *types.Named:
+				name = typ.Obj().Name()
+			default:
+				p.error("embedded field expected")
+			}
+		}
+	}
+	field = types.NewField(token.NoPos, pkg, name, typ, anon)
+	if p.tok == scanner.String {
+		tag = p.parseString()
+	}
+	return
+}
+
+// Param = Name ["..."] Type .
+func (p *parser) parseParam(pkg *types.Package) (param *types.Var, isVariadic bool) {
+	name := p.parseName()
+	// Ignore names invented for inlinable functions.
+	if strings.HasPrefix(name, "p.") || strings.HasPrefix(name, "r.") || strings.HasPrefix(name, "$ret") {
+		name = ""
+	}
+	if p.tok == '<' && p.scanner.Peek() == 'e' {
+		// EscInfo = "<esc:" int ">" . (optional and ignored)
+		p.next()
+		p.expectKeyword("esc")
+		p.expect(':')
+		p.expect(scanner.Int)
+		p.expect('>')
+	}
+	if p.tok == '.' {
+		p.next()
+		p.expect('.')
+		p.expect('.')
+		isVariadic = true
+	}
+	typ := p.parseType(pkg)
+	if isVariadic {
+		typ = types.NewSlice(typ)
+	}
+	param = types.NewParam(token.NoPos, pkg, name, typ)
+	return
+}
+
+// Var = Name Type .
+func (p *parser) parseVar(pkg *types.Package) *types.Var {
+	name := p.parseName()
+	v := types.NewVar(token.NoPos, pkg, name, p.parseType(pkg))
+	if name[0] == '.' || name[0] == '<' {
+		// This is an unexported variable,
+		// or a variable defined in a different package.
+		// We only want to record exported variables.
+		return nil
+	}
+	return v
+}
+
+// Conversion = "convert" "(" Type "," ConstValue ")" .
+func (p *parser) parseConversion(pkg *types.Package) (val constant.Value, typ types.Type) {
+	p.expectKeyword("convert")
+	p.expect('(')
+	typ = p.parseType(pkg)
+	p.expect(',')
+	val, _ = p.parseConstValue(pkg)
+	p.expect(')')
+	return
+}
+
+// ConstValue     = string | "false" | "true" | ["-"] (int ["'"] | FloatOrComplex) | Conversion .
+// FloatOrComplex = float ["i" | ("+"|"-") float "i"] .
+func (p *parser) parseConstValue(pkg *types.Package) (val constant.Value, typ types.Type) {
+	// v3 changed to $false, $true, $convert, to avoid confusion
+	// with variable names in inline function bodies.
+	if p.tok == '$' {
+		p.next()
+		if p.tok != scanner.Ident {
+			p.errorf("expected identifier after '$', got %s (%q)", scanner.TokenString(p.tok), p.lit)
+		}
+	}
+
+	switch p.tok {
+	case scanner.String:
+		str := p.parseString()
+		val = constant.MakeString(str)
+		typ = types.Typ[types.UntypedString]
+		return
+
+	case scanner.Ident:
+		b := false
+		switch p.lit {
+		case "false":
+		case "true":
+			b = true
+
+		case "convert":
+			return p.parseConversion(pkg)
+
+		default:
+			p.errorf("expected const value, got %s (%q)", scanner.TokenString(p.tok), p.lit)
+		}
+
+		p.next()
+		val = constant.MakeBool(b)
+		typ = types.Typ[types.UntypedBool]
+		return
+	}
+
+	sign := ""
+	if p.tok == '-' {
+		p.next()
+		sign = "-"
+	}
+
+	switch p.tok {
+	case scanner.Int:
+		val = constant.MakeFromLiteral(sign+p.lit, token.INT, 0)
+		if val == nil {
+			p.error("could not parse integer literal")
+		}
+
+		p.next()
+		if p.tok == '\'' {
+			p.next()
+			typ = types.Typ[types.UntypedRune]
+		} else {
+			typ = types.Typ[types.UntypedInt]
+		}
+
+	case scanner.Float:
+		re := sign + p.lit
+		p.next()
+
+		var im string
+		switch p.tok {
+		case '+':
+			p.next()
+			im = p.expect(scanner.Float)
+
+		case '-':
+			p.next()
+			im = "-" + p.expect(scanner.Float)
+
+		case scanner.Ident:
+			// re is in fact the imaginary component. Expect "i" below.
+			im = re
+			re = "0"
+
+		default:
+			val = constant.MakeFromLiteral(re, token.FLOAT, 0)
+			if val == nil {
+				p.error("could not parse float literal")
+			}
+			typ = types.Typ[types.UntypedFloat]
+			return
+		}
+
+		p.expectKeyword("i")
+		reval := constant.MakeFromLiteral(re, token.FLOAT, 0)
+		if reval == nil {
+			p.error("could not parse real component of complex literal")
+		}
+		imval := constant.MakeFromLiteral(im+"i", token.IMAG, 0)
+		if imval == nil {
+			p.error("could not parse imag component of complex literal")
+		}
+		val = constant.BinaryOp(reval, token.ADD, imval)
+		typ = types.Typ[types.UntypedComplex]
+
+	default:
+		p.errorf("expected const value, got %s (%q)", scanner.TokenString(p.tok), p.lit)
+	}
+
+	return
+}
+
+// Const = Name [Type] "=" ConstValue .
+func (p *parser) parseConst(pkg *types.Package) *types.Const {
+	name := p.parseName()
+	var typ types.Type
+	if p.tok == '<' {
+		typ = p.parseType(pkg)
+	}
+	p.expect('=')
+	val, vtyp := p.parseConstValue(pkg)
+	if typ == nil {
+		typ = vtyp
+	}
+	return types.NewConst(token.NoPos, pkg, name, typ, val)
+}
+
+// reserved is a singleton type used to fill type map slots that have
+// been reserved (i.e., for which a type number has been parsed) but
+// which don't have their actual type yet. When the type map is updated,
+// the actual type must replace a reserved entry (or we have an internal
+// error). Used for self-verification only - not required for correctness.
+var reserved = new(struct{ types.Type })
+
+// reserve reserves the type map entry n for future use.
+func (p *parser) reserve(n int) {
+	// Notes:
+	// - for pre-V3 export data, the type numbers we see are
+	//   guaranteed to be in increasing order, so we append a
+	//   reserved entry onto the list.
+	// - for V3+ export data, type numbers can appear in
+	//   any order, however the 'types' section tells us the
+	//   total number of types, hence typeList is pre-allocated.
+	if len(p.typeData) == 0 {
+		if n != len(p.typeList) {
+			p.errorf("invalid type number %d (out of sync)", n)
+		}
+		p.typeList = append(p.typeList, reserved)
+	} else {
+		if p.typeList[n] != nil {
+			p.errorf("previously visited type number %d", n)
+		}
+		p.typeList[n] = reserved
+	}
+}
+
+// update sets the type map entries for the entries in nlist to t.
+// An entry in nlist can be a type number in p.typeList,
+// used to resolve named types, or it can be a *types.Pointer,
+// used to resolve pointers to named types in case they are referenced
+// by embedded fields.
+func (p *parser) update(t types.Type, nlist []interface{}) {
+	if t == reserved {
+		p.errorf("internal error: update(%v) invoked on reserved", nlist)
+	}
+	if t == nil {
+		p.errorf("internal error: update(%v) invoked on nil", nlist)
+	}
+	for _, n := range nlist {
+		switch n := n.(type) {
+		case int:
+			if p.typeList[n] == t {
+				continue
+			}
+			if p.typeList[n] != reserved {
+				p.errorf("internal error: update(%v): %d not reserved", nlist, n)
+			}
+			p.typeList[n] = t
+		case *types.Pointer:
+			if *n != (types.Pointer{}) {
+				elem := n.Elem()
+				if elem == t {
+					continue
+				}
+				p.errorf("internal error: update: pointer already set to %v, expected %v", elem, t)
+			}
+			*n = *types.NewPointer(t)
+		default:
+			p.errorf("internal error: %T on nlist", n)
+		}
+	}
+}
+
+// NamedType = TypeName [ "=" ] Type { Method } .
+// TypeName  = ExportedName .
+// Method    = "func" "(" Param ")" Name ParamList ResultList [InlineBody] ";" .
+func (p *parser) parseNamedType(nlist []interface{}) types.Type {
+	pkg, name := p.parseExportedName()
+	scope := pkg.Scope()
+	obj := scope.Lookup(name)
+	if obj != nil && obj.Type() == nil {
+		p.errorf("%v has nil type", obj)
+	}
+
+	if p.tok == scanner.Ident && p.lit == "notinheap" {
+		p.next()
+		// The go/types package has no way of recording that
+		// this type is marked notinheap. Presumably no user
+		// of this package actually cares.
+	}
+
+	// type alias
+	if p.tok == '=' {
+		p.next()
+		p.aliases[nlist[len(nlist)-1].(int)] = name
+		if obj != nil {
+			// use the previously imported (canonical) type
+			t := obj.Type()
+			p.update(t, nlist)
+			p.parseType(pkg) // discard
+			return t
+		}
+		t := p.parseType(pkg, nlist...)
+		obj = types.NewTypeName(token.NoPos, pkg, name, t)
+		scope.Insert(obj)
+		return t
+	}
+
+	// defined type
+	if obj == nil {
+		// A named type may be referred to before the underlying type
+		// is known - set it up.
+		tname := types.NewTypeName(token.NoPos, pkg, name, nil)
+		types.NewNamed(tname, nil, nil)
+		scope.Insert(tname)
+		obj = tname
+	}
+
+	// use the previously imported (canonical), or newly created type
+	t := obj.Type()
+	p.update(t, nlist)
+
+	nt, ok := t.(*types.Named)
+	if !ok {
+		// This can happen for unsafe.Pointer, which is a TypeName holding a Basic type.
+		pt := p.parseType(pkg)
+		if pt != t {
+			p.error("unexpected underlying type for non-named TypeName")
+		}
+		return t
+	}
+
+	underlying := p.parseType(pkg)
+	if nt.Underlying() == nil {
+		if underlying.Underlying() == nil {
+			fix := fixupRecord{toUpdate: nt, target: underlying}
+			p.fixups = append(p.fixups, fix)
+		} else {
+			nt.SetUnderlying(underlying.Underlying())
+		}
+	}
+
+	if p.tok == '\n' {
+		p.next()
+		// collect associated methods
+		for p.tok == scanner.Ident {
+			p.expectKeyword("func")
+			if p.tok == '/' {
+				// Skip a /*nointerface*/ or /*asm ID */ comment.
+				p.expect('/')
+				p.expect('*')
+				if p.expect(scanner.Ident) == "asm" {
+					p.parseUnquotedString()
+				}
+				p.expect('*')
+				p.expect('/')
+			}
+			p.expect('(')
+			receiver, _ := p.parseParam(pkg)
+			p.expect(')')
+			name := p.parseName()
+			params, isVariadic := p.parseParamList(pkg)
+			results := p.parseResultList(pkg)
+			p.skipInlineBody()
+			p.expectEOL()
+
+			sig := types.NewSignature(receiver, params, results, isVariadic)
+			nt.AddMethod(types.NewFunc(token.NoPos, pkg, name, sig))
+		}
+	}
+
+	return nt
+}
+
+func (p *parser) parseInt64() int64 {
+	lit := p.expect(scanner.Int)
+	n, err := strconv.ParseInt(lit, 10, 64)
+	if err != nil {
+		p.error(err)
+	}
+	return n
+}
+
+func (p *parser) parseInt() int {
+	lit := p.expect(scanner.Int)
+	n, err := strconv.ParseInt(lit, 10, 0 /* int */)
+	if err != nil {
+		p.error(err)
+	}
+	return int(n)
+}
+
+// ArrayOrSliceType = "[" [ int ] "]" Type .
+func (p *parser) parseArrayOrSliceType(pkg *types.Package, nlist []interface{}) types.Type {
+	p.expect('[')
+	if p.tok == ']' {
+		p.next()
+
+		t := new(types.Slice)
+		p.update(t, nlist)
+
+		*t = *types.NewSlice(p.parseType(pkg))
+		return t
+	}
+
+	t := new(types.Array)
+	p.update(t, nlist)
+
+	len := p.parseInt64()
+	p.expect(']')
+
+	*t = *types.NewArray(p.parseType(pkg), len)
+	return t
+}
+
+// MapType = "map" "[" Type "]" Type .
+func (p *parser) parseMapType(pkg *types.Package, nlist []interface{}) types.Type {
+	p.expectKeyword("map")
+
+	t := new(types.Map)
+	p.update(t, nlist)
+
+	p.expect('[')
+	key := p.parseType(pkg)
+	p.expect(']')
+	elem := p.parseType(pkg)
+
+	*t = *types.NewMap(key, elem)
+	return t
+}
+
+// ChanType = "chan" ["<-" | "-<"] Type .
+func (p *parser) parseChanType(pkg *types.Package, nlist []interface{}) types.Type {
+	p.expectKeyword("chan")
+
+	t := new(types.Chan)
+	p.update(t, nlist)
+
+	dir := types.SendRecv
+	switch p.tok {
+	case '-':
+		p.next()
+		p.expect('<')
+		dir = types.SendOnly
+
+	case '<':
+		// don't consume '<' if it belongs to Type
+		if p.scanner.Peek() == '-' {
+			p.next()
+			p.expect('-')
+			dir = types.RecvOnly
+		}
+	}
+
+	*t = *types.NewChan(dir, p.parseType(pkg))
+	return t
+}
+
+// StructType = "struct" "{" { Field } "}" .
+func (p *parser) parseStructType(pkg *types.Package, nlist []interface{}) types.Type {
+	p.expectKeyword("struct")
+
+	t := new(types.Struct)
+	p.update(t, nlist)
+
+	var fields []*types.Var
+	var tags []string
+
+	p.expect('{')
+	for p.tok != '}' && p.tok != scanner.EOF {
+		field, tag := p.parseField(pkg)
+		p.expect(';')
+		fields = append(fields, field)
+		tags = append(tags, tag)
+	}
+	p.expect('}')
+
+	*t = *types.NewStruct(fields, tags)
+	return t
+}
+
+// ParamList = "(" [ { Parameter "," } Parameter ] ")" .
+func (p *parser) parseParamList(pkg *types.Package) (*types.Tuple, bool) {
+	var list []*types.Var
+	isVariadic := false
+
+	p.expect('(')
+	for p.tok != ')' && p.tok != scanner.EOF {
+		if len(list) > 0 {
+			p.expect(',')
+		}
+		par, variadic := p.parseParam(pkg)
+		list = append(list, par)
+		if variadic {
+			if isVariadic {
+				p.error("... not on final argument")
+			}
+			isVariadic = true
+		}
+	}
+	p.expect(')')
+
+	return types.NewTuple(list...), isVariadic
+}
+
+// ResultList = Type | ParamList .
+func (p *parser) parseResultList(pkg *types.Package) *types.Tuple {
+	switch p.tok {
+	case '<':
+		p.next()
+		if p.tok == scanner.Ident && p.lit == "inl" {
+			return nil
+		}
+		taa, _ := p.parseTypeAfterAngle(pkg)
+		return types.NewTuple(types.NewParam(token.NoPos, pkg, "", taa))
+
+	case '(':
+		params, _ := p.parseParamList(pkg)
+		return params
+
+	default:
+		return nil
+	}
+}
+
+// FunctionType = ParamList ResultList .
+func (p *parser) parseFunctionType(pkg *types.Package, nlist []interface{}) *types.Signature {
+	t := new(types.Signature)
+	p.update(t, nlist)
+
+	params, isVariadic := p.parseParamList(pkg)
+	results := p.parseResultList(pkg)
+
+	*t = *types.NewSignature(nil, params, results, isVariadic)
+	return t
+}
+
+// Func = Name FunctionType [InlineBody] .
+func (p *parser) parseFunc(pkg *types.Package) *types.Func {
+	if p.tok == '/' {
+		// Skip an /*asm ID */ comment.
+		p.expect('/')
+		p.expect('*')
+		if p.expect(scanner.Ident) == "asm" {
+			p.parseUnquotedString()
+		}
+		p.expect('*')
+		p.expect('/')
+	}
+
+	name := p.parseName()
+	f := types.NewFunc(token.NoPos, pkg, name, p.parseFunctionType(pkg, nil))
+	p.skipInlineBody()
+
+	if name[0] == '.' || name[0] == '<' || strings.ContainsRune(name, '$') {
+		// This is an unexported function,
+		// or a function defined in a different package,
+		// or a type$equal or type$hash function.
+		// We only want to record exported functions.
+		return nil
+	}
+
+	return f
+}
+
+// InterfaceType = "interface" "{" { ("?" Type | Func) ";" } "}" .
+func (p *parser) parseInterfaceType(pkg *types.Package, nlist []interface{}) types.Type {
+	p.expectKeyword("interface")
+
+	t := new(types.Interface)
+	p.update(t, nlist)
+
+	var methods []*types.Func
+	var embeddeds []types.Type
+
+	p.expect('{')
+	for p.tok != '}' && p.tok != scanner.EOF {
+		if p.tok == '?' {
+			p.next()
+			embeddeds = append(embeddeds, p.parseType(pkg))
+		} else {
+			method := p.parseFunc(pkg)
+			if method != nil {
+				methods = append(methods, method)
+			}
+		}
+		p.expect(';')
+	}
+	p.expect('}')
+
+	*t = *types.NewInterfaceType(methods, embeddeds)
+	return t
+}
+
+// PointerType = "*" ("any" | Type) .
+func (p *parser) parsePointerType(pkg *types.Package, nlist []interface{}) types.Type {
+	p.expect('*')
+	if p.tok == scanner.Ident {
+		p.expectKeyword("any")
+		t := types.Typ[types.UnsafePointer]
+		p.update(t, nlist)
+		return t
+	}
+
+	t := new(types.Pointer)
+	p.update(t, nlist)
+
+	*t = *types.NewPointer(p.parseType(pkg, t))
+
+	return t
+}
+
+// TypeSpec = NamedType | MapType | ChanType | StructType | InterfaceType | PointerType | ArrayOrSliceType | FunctionType .
+func (p *parser) parseTypeSpec(pkg *types.Package, nlist []interface{}) types.Type {
+	switch p.tok {
+	case scanner.String:
+		return p.parseNamedType(nlist)
+
+	case scanner.Ident:
+		switch p.lit {
+		case "map":
+			return p.parseMapType(pkg, nlist)
+
+		case "chan":
+			return p.parseChanType(pkg, nlist)
+
+		case "struct":
+			return p.parseStructType(pkg, nlist)
+
+		case "interface":
+			return p.parseInterfaceType(pkg, nlist)
+		}
+
+	case '*':
+		return p.parsePointerType(pkg, nlist)
+
+	case '[':
+		return p.parseArrayOrSliceType(pkg, nlist)
+
+	case '(':
+		return p.parseFunctionType(pkg, nlist)
+	}
+
+	p.errorf("expected type name or literal, got %s", scanner.TokenString(p.tok))
+	return nil
+}
+
+const (
+	// From gofrontend/go/export.h
+	// Note that these values are negative in the gofrontend and have been made positive
+	// in the gccgoimporter.
+	gccgoBuiltinINT8       = 1
+	gccgoBuiltinINT16      = 2
+	gccgoBuiltinINT32      = 3
+	gccgoBuiltinINT64      = 4
+	gccgoBuiltinUINT8      = 5
+	gccgoBuiltinUINT16     = 6
+	gccgoBuiltinUINT32     = 7
+	gccgoBuiltinUINT64     = 8
+	gccgoBuiltinFLOAT32    = 9
+	gccgoBuiltinFLOAT64    = 10
+	gccgoBuiltinINT        = 11
+	gccgoBuiltinUINT       = 12
+	gccgoBuiltinUINTPTR    = 13
+	gccgoBuiltinBOOL       = 15
+	gccgoBuiltinSTRING     = 16
+	gccgoBuiltinCOMPLEX64  = 17
+	gccgoBuiltinCOMPLEX128 = 18
+	gccgoBuiltinERROR      = 19
+	gccgoBuiltinBYTE       = 20
+	gccgoBuiltinRUNE       = 21
+)
+
+func lookupBuiltinType(typ int) types.Type {
+	return [...]types.Type{
+		gccgoBuiltinINT8:       types.Typ[types.Int8],
+		gccgoBuiltinINT16:      types.Typ[types.Int16],
+		gccgoBuiltinINT32:      types.Typ[types.Int32],
+		gccgoBuiltinINT64:      types.Typ[types.Int64],
+		gccgoBuiltinUINT8:      types.Typ[types.Uint8],
+		gccgoBuiltinUINT16:     types.Typ[types.Uint16],
+		gccgoBuiltinUINT32:     types.Typ[types.Uint32],
+		gccgoBuiltinUINT64:     types.Typ[types.Uint64],
+		gccgoBuiltinFLOAT32:    types.Typ[types.Float32],
+		gccgoBuiltinFLOAT64:    types.Typ[types.Float64],
+		gccgoBuiltinINT:        types.Typ[types.Int],
+		gccgoBuiltinUINT:       types.Typ[types.Uint],
+		gccgoBuiltinUINTPTR:    types.Typ[types.Uintptr],
+		gccgoBuiltinBOOL:       types.Typ[types.Bool],
+		gccgoBuiltinSTRING:     types.Typ[types.String],
+		gccgoBuiltinCOMPLEX64:  types.Typ[types.Complex64],
+		gccgoBuiltinCOMPLEX128: types.Typ[types.Complex128],
+		gccgoBuiltinERROR:      types.Universe.Lookup("error").Type(),
+		gccgoBuiltinBYTE:       types.Universe.Lookup("byte").Type(),
+		gccgoBuiltinRUNE:       types.Universe.Lookup("rune").Type(),
+	}[typ]
+}
+
+// Type = "<" "type" ( "-" int | int [ TypeSpec ] ) ">" .
+//
+// parseType updates the type map to t for all type numbers n.
+//
+func (p *parser) parseType(pkg *types.Package, n ...interface{}) types.Type {
+	p.expect('<')
+	t, _ := p.parseTypeAfterAngle(pkg, n...)
+	return t
+}
+
+// (*parser).Type after reading the "<".
+func (p *parser) parseTypeAfterAngle(pkg *types.Package, n ...interface{}) (t types.Type, n1 int) {
+	p.expectKeyword("type")
+
+	n1 = 0
+	switch p.tok {
+	case scanner.Int:
+		n1 = p.parseInt()
+		if p.tok == '>' {
+			if len(p.typeData) > 0 && p.typeList[n1] == nil {
+				p.parseSavedType(pkg, n1, n)
+			}
+			t = p.typeList[n1]
+			if len(p.typeData) == 0 && t == reserved {
+				p.errorf("invalid type cycle, type %d not yet defined (nlist=%v)", n1, n)
+			}
+			p.update(t, n)
+		} else {
+			p.reserve(n1)
+			t = p.parseTypeSpec(pkg, append(n, n1))
+		}
+
+	case '-':
+		p.next()
+		n1 := p.parseInt()
+		t = lookupBuiltinType(n1)
+		p.update(t, n)
+
+	default:
+		p.errorf("expected type number, got %s (%q)", scanner.TokenString(p.tok), p.lit)
+		return nil, 0
+	}
+
+	if t == nil || t == reserved {
+		p.errorf("internal error: bad return from parseType(%v)", n)
+	}
+
+	p.expect('>')
+	return
+}
+
+// parseTypeExtended is identical to parseType, but if the type in
+// question is a saved type, returns the index as well as the type
+// pointer (index returned is zero if we parsed a builtin).
+func (p *parser) parseTypeExtended(pkg *types.Package, n ...interface{}) (t types.Type, n1 int) {
+	p.expect('<')
+	t, n1 = p.parseTypeAfterAngle(pkg, n...)
+	return
+}
+
+// InlineBody = "<inl:NN>" .{NN}
+// Reports whether a body was skipped.
+func (p *parser) skipInlineBody() {
+	// We may or may not have seen the '<' already, depending on
+	// whether the function had a result type or not.
+	if p.tok == '<' {
+		p.next()
+		p.expectKeyword("inl")
+	} else if p.tok != scanner.Ident || p.lit != "inl" {
+		return
+	} else {
+		p.next()
+	}
+
+	p.expect(':')
+	want := p.parseInt()
+	p.expect('>')
+
+	defer func(w uint64) {
+		p.scanner.Whitespace = w
+	}(p.scanner.Whitespace)
+	p.scanner.Whitespace = 0
+
+	got := 0
+	for got < want {
+		r := p.scanner.Next()
+		if r == scanner.EOF {
+			p.error("unexpected EOF")
+		}
+		got += utf8.RuneLen(r)
+	}
+}
+
+// Types = "types" maxp1 exportedp1 (offset length)* .
+func (p *parser) parseTypes(pkg *types.Package) {
+	maxp1 := p.parseInt()
+	exportedp1 := p.parseInt()
+	p.typeList = make([]types.Type, maxp1, maxp1)
+
+	type typeOffset struct {
+		offset int
+		length int
+	}
+	var typeOffsets []typeOffset
+
+	total := 0
+	for i := 1; i < maxp1; i++ {
+		len := p.parseInt()
+		typeOffsets = append(typeOffsets, typeOffset{total, len})
+		total += len
+	}
+
+	defer func(w uint64) {
+		p.scanner.Whitespace = w
+	}(p.scanner.Whitespace)
+	p.scanner.Whitespace = 0
+
+	// We should now have p.tok pointing to the final newline.
+	// The next runes from the scanner should be the type data.
+
+	var sb strings.Builder
+	for sb.Len() < total {
+		r := p.scanner.Next()
+		if r == scanner.EOF {
+			p.error("unexpected EOF")
+		}
+		sb.WriteRune(r)
+	}
+	allTypeData := sb.String()
+
+	p.typeData = []string{""} // type 0, unused
+	for _, to := range typeOffsets {
+		p.typeData = append(p.typeData, allTypeData[to.offset:to.offset+to.length])
+	}
+
+	for i := 1; i < int(exportedp1); i++ {
+		p.parseSavedType(pkg, i, nil)
+	}
+}
+
+// parseSavedType parses one saved type definition.
+func (p *parser) parseSavedType(pkg *types.Package, i int, nlist []interface{}) {
+	defer func(s *scanner.Scanner, tok rune, lit string) {
+		p.scanner = s
+		p.tok = tok
+		p.lit = lit
+	}(p.scanner, p.tok, p.lit)
+
+	p.scanner = new(scanner.Scanner)
+	p.initScanner(p.scanner.Filename, strings.NewReader(p.typeData[i]))
+	p.expectKeyword("type")
+	id := p.parseInt()
+	if id != i {
+		p.errorf("type ID mismatch: got %d, want %d", id, i)
+	}
+	if p.typeList[i] == reserved {
+		p.errorf("internal error: %d already reserved in parseSavedType", i)
+	}
+	if p.typeList[i] == nil {
+		p.reserve(i)
+		p.parseTypeSpec(pkg, append(nlist, i))
+	}
+	if p.typeList[i] == nil || p.typeList[i] == reserved {
+		p.errorf("internal error: parseSavedType(%d,%v) reserved/nil", i, nlist)
+	}
+}
+
+// PackageInit = unquotedString unquotedString int .
+func (p *parser) parsePackageInit() PackageInit {
+	name := p.parseUnquotedString()
+	initfunc := p.parseUnquotedString()
+	priority := -1
+	if p.version == "v1" {
+		priority = p.parseInt()
+	}
+	return PackageInit{Name: name, InitFunc: initfunc, Priority: priority}
+}
+
+// Create the package if we have parsed both the package path and package name.
+func (p *parser) maybeCreatePackage() {
+	if p.pkgname != "" && p.pkgpath != "" {
+		p.pkg = p.getPkg(p.pkgpath, p.pkgname)
+	}
+}
+
+// InitDataDirective = ( "v1" | "v2" | "v3" ) ";" |
+//                     "priority" int ";" |
+//                     "init" { PackageInit } ";" |
+//                     "checksum" unquotedString ";" .
+func (p *parser) parseInitDataDirective() {
+	if p.tok != scanner.Ident {
+		// unexpected token kind; panic
+		p.expect(scanner.Ident)
+	}
+
+	switch p.lit {
+	case "v1", "v2", "v3":
+		p.version = p.lit
+		p.next()
+		p.expect(';')
+		p.expect('\n')
+
+	case "priority":
+		p.next()
+		p.initdata.Priority = p.parseInt()
+		p.expectEOL()
+
+	case "init":
+		p.next()
+		for p.tok != '\n' && p.tok != ';' && p.tok != scanner.EOF {
+			p.initdata.Inits = append(p.initdata.Inits, p.parsePackageInit())
+		}
+		p.expectEOL()
+
+	case "init_graph":
+		p.next()
+		// The graph data is thrown away for now.
+		for p.tok != '\n' && p.tok != ';' && p.tok != scanner.EOF {
+			p.parseInt64()
+			p.parseInt64()
+		}
+		p.expectEOL()
+
+	case "checksum":
+		// Don't let the scanner try to parse the checksum as a number.
+		defer func(mode uint) {
+			p.scanner.Mode = mode
+		}(p.scanner.Mode)
+		p.scanner.Mode &^= scanner.ScanInts | scanner.ScanFloats
+		p.next()
+		p.parseUnquotedString()
+		p.expectEOL()
+
+	default:
+		p.errorf("unexpected identifier: %q", p.lit)
+	}
+}
+
+// Directive = InitDataDirective |
+//             "package" unquotedString [ unquotedString ] [ unquotedString ] ";" |
+//             "pkgpath" unquotedString ";" |
+//             "prefix" unquotedString ";" |
+//             "import" unquotedString unquotedString string ";" |
+//             "indirectimport" unquotedString unquotedstring ";" |
+//             "func" Func ";" |
+//             "type" Type ";" |
+//             "var" Var ";" |
+//             "const" Const ";" .
+func (p *parser) parseDirective() {
+	if p.tok != scanner.Ident {
+		// unexpected token kind; panic
+		p.expect(scanner.Ident)
+	}
+
+	switch p.lit {
+	case "v1", "v2", "v3", "priority", "init", "init_graph", "checksum":
+		p.parseInitDataDirective()
+
+	case "package":
+		p.next()
+		p.pkgname = p.parseUnquotedString()
+		p.maybeCreatePackage()
+		if p.version != "v1" && p.tok != '\n' && p.tok != ';' {
+			p.parseUnquotedString()
+			p.parseUnquotedString()
+		}
+		p.expectEOL()
+
+	case "pkgpath":
+		p.next()
+		p.pkgpath = p.parseUnquotedString()
+		p.maybeCreatePackage()
+		p.expectEOL()
+
+	case "prefix":
+		p.next()
+		p.pkgpath = p.parseUnquotedString()
+		p.expectEOL()
+
+	case "import":
+		p.next()
+		pkgname := p.parseUnquotedString()
+		pkgpath := p.parseUnquotedString()
+		p.getPkg(pkgpath, pkgname)
+		p.parseString()
+		p.expectEOL()
+
+	case "indirectimport":
+		p.next()
+		pkgname := p.parseUnquotedString()
+		pkgpath := p.parseUnquotedString()
+		p.getPkg(pkgpath, pkgname)
+		p.expectEOL()
+
+	case "types":
+		p.next()
+		p.parseTypes(p.pkg)
+		p.expectEOL()
+
+	case "func":
+		p.next()
+		fun := p.parseFunc(p.pkg)
+		if fun != nil {
+			p.pkg.Scope().Insert(fun)
+		}
+		p.expectEOL()
+
+	case "type":
+		p.next()
+		p.parseType(p.pkg)
+		p.expectEOL()
+
+	case "var":
+		p.next()
+		v := p.parseVar(p.pkg)
+		if v != nil {
+			p.pkg.Scope().Insert(v)
+		}
+		p.expectEOL()
+
+	case "const":
+		p.next()
+		c := p.parseConst(p.pkg)
+		p.pkg.Scope().Insert(c)
+		p.expectEOL()
+
+	default:
+		p.errorf("unexpected identifier: %q", p.lit)
+	}
+}
+
+// Package = { Directive } .
+func (p *parser) parsePackage() *types.Package {
+	for p.tok != scanner.EOF {
+		p.parseDirective()
+	}
+	for _, f := range p.fixups {
+		if f.target.Underlying() == nil {
+			p.errorf("internal error: fixup can't be applied, loop required")
+		}
+		f.toUpdate.SetUnderlying(f.target.Underlying())
+	}
+	p.fixups = nil
+	for _, typ := range p.typeList {
+		if it, ok := typ.(*types.Interface); ok {
+			it.Complete()
+		}
+	}
+	p.pkg.MarkComplete()
+	return p.pkg
+}