go/...: make most tests pass with gccgo

There is one non-test change: have FakeContext change the compiler to
"gc", as callers expect to be accessing a gc-style GOROOT.

The go/pointer, go/ssa, and go/ssa/interp tests still fail with gccgo.

Change-Id: I850c9618401f6b9e63d7ca7196f91931b03f1524
Reviewed-on: https://go-review.googlesource.com/117395
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

go/buildutil/allpackages_test.go

@@ -10,6 +10,7 @@ package buildutil_test
 
 import (
 	"go/build"
+	"runtime"
 	"sort"
 	"strings"
 	"testing"
@@ -18,6 +19,10 @@ import (
 )
 
 func TestAllPackages(t *testing.T) {
+	if runtime.Compiler == "gccgo" {
+		t.Skip("gccgo has no standard packages")
+	}
+
 	all := buildutil.AllPackages(&build.Default)
 
 	set := make(map[string]bool)

go/buildutil/fakecontext.go

@@ -41,6 +41,7 @@ func FakeContext(pkgs map[string]map[string]string) *build.Context {
 	ctxt := build.Default // copy
 	ctxt.GOROOT = "/go"
 	ctxt.GOPATH = ""
+	ctxt.Compiler = "gc"
 	ctxt.IsDir = func(dir string) bool {
 		dir = clean(dir)
 		if dir == "" {

go/buildutil/util_test.go

@@ -15,6 +15,10 @@ import (
 )
 
 func TestContainingPackage(t *testing.T) {
+	if runtime.Compiler == "gccgo" {
+		t.Skip("gccgo has no GOROOT")
+	}
+
 	// unvirtualized:
 	goroot := runtime.GOROOT()
 	gopath := gopathContainingTools(t)

go/gcexportdata/example_test.go

@@ -3,6 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build go1.7
+// +build gc
 
 package gcexportdata_test
 

go/internal/gccgoimporter/gccgoinstallation_test.go

@@ -64,8 +64,6 @@ var importablePackages = [...]string{
 	"encoding/pem",
 	"encoding/xml",
 	"errors",
-	"exp/proxy",
-	"exp/terminal",
 	"expvar",
 	"flag",
 	"fmt",
@@ -116,8 +114,6 @@ var importablePackages = [...]string{
 	"net/smtp",
 	"net/textproto",
 	"net/url",
-	"old/regexp",
-	"old/template",
 	"os/exec",
 	"os",
 	"os/signal",
@@ -183,12 +179,12 @@ func TestInstallationImporter(t *testing.T) {
 
 	// Test for certain specific entities in the imported data.
 	for _, test := range [...]importerTest{
-		{pkgpath: "io", name: "Reader", want: "type Reader interface{Read(p []uint8) (n int, err error)}"},
+		{pkgpath: "io", name: "Reader", want: "type Reader interface{Read(p []byte) (n int, err error)}"},
 		{pkgpath: "io", name: "ReadWriter", want: "type ReadWriter interface{Reader; Writer}"},
 		{pkgpath: "math", name: "Pi", want: "const Pi untyped float"},
 		{pkgpath: "math", name: "Sin", want: "func Sin(x float64) float64"},
 		{pkgpath: "sort", name: "Ints", want: "func Ints(a []int)"},
-		{pkgpath: "unsafe", name: "Pointer", want: "type Pointer unsafe.Pointer"},
+		{pkgpath: "unsafe", name: "Pointer", want: "type Pointer"},
 	} {
 		runImporterTest(t, imp, nil, &test)
 	}

go/internal/gccgoimporter/importer_test.go

@@ -144,6 +144,13 @@ func TestObjImporter(t *testing.T) {
 
 	for _, test := range importerTests {
 		gofile := filepath.Join("testdata", test.pkgpath+".go")
+
+		if _, err := os.Stat(gofile); err != nil {
+			// There is a .gox file but no .go file,
+			// so there is nothing to compile.
+			continue
+		}
+
 		ofile := filepath.Join(tmpdir, test.pkgpath+".o")
 		afile := filepath.Join(artmpdir, "lib"+test.pkgpath+".a")
 
@@ -154,6 +161,10 @@ func TestObjImporter(t *testing.T) {
 			t.Fatalf("gccgo %s failed: %s", gofile, err)
 		}
 
+		// The expected initializations are version dependent,
+		// so don't check for them.
+		test.wantinits = nil
+
 		runImporterTest(t, imp, initmap, &test)
 
 		cmd = exec.Command("ar", "cr", afile, ofile)

go/internal/gcimporter/bexport_test.go

@@ -23,6 +23,9 @@ import (
 )
 
 func TestBExportData_stdlib(t *testing.T) {
+	if runtime.Compiler == "gccgo" {
+		t.Skip("gccgo standard library is inaccessible")
+	}
 	if runtime.GOOS == "android" {
 		t.Skipf("incomplete std lib on %s", runtime.GOOS)
 	}

go/loader/loader_test.go

@@ -15,6 +15,7 @@ import (
 	"go/types"
 	"path/filepath"
 	"reflect"
+	"runtime"
 	"sort"
 	"strings"
 	"sync"
@@ -127,6 +128,10 @@ func TestLoad_MissingInitialPackage(t *testing.T) {
 }
 
 func TestLoad_MissingInitialPackage_AllowErrors(t *testing.T) {
+	if runtime.Compiler == "gccgo" {
+		t.Skip("gccgo has no standard library test files")
+	}
+
 	var conf loader.Config
 	conf.AllowErrors = true
 	conf.Import("nosuchpkg")
@@ -251,6 +256,10 @@ func TestLoad_FromSource_Success(t *testing.T) {
 }
 
 func TestLoad_FromImports_Success(t *testing.T) {
+	if runtime.Compiler == "gccgo" {
+		t.Skip("gccgo has no standard library test files")
+	}
+
 	var conf loader.Config
 	conf.ImportWithTests("fmt")
 	conf.ImportWithTests("errors")