go/internal/gccgoimporter: accept missed portions of v2 format

Fixes #18301.

Change-Id: I990c105904ab62f2225d671bbc10209ec51b12e2
Reviewed-on: https://go-review.googlesource.com/34371
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>

src/go/internal/gccgoimporter/importer_test.go

@@ -96,8 +96,11 @@ var importerTests = [...]importerTest{
 	{pkgpath: "complexnums", name: "PN", want: "const PN untyped complex", wantval: "(1 + -1i)"},
 	{pkgpath: "complexnums", name: "PP", want: "const PP untyped complex", wantval: "(1 + 1i)"},
 	{pkgpath: "conversions", name: "Bits", want: "const Bits Units", wantval: `"bits"`},
-	// TODO: enable this entry once bug has been tracked down
-	//{pkgpath: "imports", wantinits: []string{"imports..import", "fmt..import", "math..import"}},
+	{pkgpath: "time", name: "Duration", want: "type Duration int64"},
+	{pkgpath: "time", name: "Nanosecond", want: "const Nanosecond Duration", wantval: "1"},
+	{pkgpath: "unicode", name: "IsUpper", want: "func IsUpper(r rune) bool"},
+	{pkgpath: "unicode", name: "MaxRune", want: "const MaxRune untyped rune", wantval: "1114111"},
+	{pkgpath: "imports", wantinits: []string{"imports..import", "fmt..import", "math..import"}},
 }
 
 func TestGoxImporter(t *testing.T) {

src/go/internal/gccgoimporter/parser.go

@@ -711,7 +711,10 @@ func (p *parser) parseType(pkg *types.Package) (t types.Type) {
 func (p *parser) parsePackageInit() PackageInit {
 	name := p.parseUnquotedString()
 	initfunc := p.parseUnquotedString()
-	priority := int(p.parseInt())
+	priority := -1
+	if p.version == "v1" {
+		priority = int(p.parseInt())
+	}
 	return PackageInit{Name: name, InitFunc: initfunc, Priority: priority}
 }
 
@@ -766,6 +769,15 @@ func (p *parser) parseInitDataDirective() {
 		}
 		p.expect(';')
 
+	case "init_graph":
+		p.next()
+		// The graph data is thrown away for now.
+		for p.tok != ';' && p.tok != scanner.EOF {
+			p.parseInt()
+			p.parseInt()
+		}
+		p.expect(';')
+
 	case "checksum":
 		// Don't let the scanner try to parse the checksum as a number.
 		defer func(mode uint) {
@@ -797,7 +809,7 @@ func (p *parser) parseDirective() {
 	}
 
 	switch p.lit {
-	case "v1", "v2", "priority", "init", "checksum":
+	case "v1", "v2", "priority", "init", "init_graph", "checksum":
 		p.parseInitDataDirective()
 
 	case "package":