blob: 70516703d96041072c2ab75c17b17f9543aa3c94 [file] [log] [blame]
// Copyright 2016 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 carchive_test
import (
"bufio"
"bytes"
"debug/elf"
"flag"
"fmt"
"io/ioutil"
"log"
"os"
"os/exec"
"path/filepath"
"regexp"
"runtime"
"strings"
"syscall"
"testing"
"time"
"unicode"
)
// Program to run.
var bin []string
// C compiler with args (from $(go env CC) $(go env GOGCCFLAGS)).
var cc []string
// ".exe" on Windows.
var exeSuffix string
var GOOS, GOARCH, GOPATH string
var libgodir string
func TestMain(m *testing.M) {
flag.Parse()
if testing.Short() && os.Getenv("GO_BUILDER_NAME") == "" {
fmt.Printf("SKIP - short mode and $GO_BUILDER_NAME not set\n")
os.Exit(0)
}
log.SetFlags(log.Lshortfile)
os.Exit(testMain(m))
}
func testMain(m *testing.M) int {
// We need a writable GOPATH in which to run the tests.
// Construct one in a temporary directory.
var err error
GOPATH, err = ioutil.TempDir("", "carchive_test")
if err != nil {
log.Panic(err)
}
defer os.RemoveAll(GOPATH)
os.Setenv("GOPATH", GOPATH)
// Copy testdata into GOPATH/src/testarchive, along with a go.mod file
// declaring the same path.
modRoot := filepath.Join(GOPATH, "src", "testcarchive")
if err := overlayDir(modRoot, "testdata"); err != nil {
log.Panic(err)
}
if err := os.Chdir(modRoot); err != nil {
log.Panic(err)
}
os.Setenv("PWD", modRoot)
if err := ioutil.WriteFile("go.mod", []byte("module testcarchive\n"), 0666); err != nil {
log.Panic(err)
}
GOOS = goEnv("GOOS")
GOARCH = goEnv("GOARCH")
bin = cmdToRun("./testp")
ccOut := goEnv("CC")
cc = []string{string(ccOut)}
out := goEnv("GOGCCFLAGS")
quote := '\000'
start := 0
lastSpace := true
backslash := false
s := string(out)
for i, c := range s {
if quote == '\000' && unicode.IsSpace(c) {
if !lastSpace {
cc = append(cc, s[start:i])
lastSpace = true
}
} else {
if lastSpace {
start = i
lastSpace = false
}
if quote == '\000' && !backslash && (c == '"' || c == '\'') {
quote = c
backslash = false
} else if !backslash && quote == c {
quote = '\000'
} else if (quote == '\000' || quote == '"') && !backslash && c == '\\' {
backslash = true
} else {
backslash = false
}
}
}
if !lastSpace {
cc = append(cc, s[start:])
}
if GOOS == "darwin" {
// For Darwin/ARM.
// TODO(crawshaw): can we do better?
cc = append(cc, []string{"-framework", "CoreFoundation", "-framework", "Foundation"}...)
}
if GOOS == "aix" {
// -Wl,-bnoobjreorder is mandatory to keep the same layout
// in .text section.
cc = append(cc, "-Wl,-bnoobjreorder")
}
libbase := GOOS + "_" + GOARCH
if runtime.Compiler == "gccgo" {
libbase = "gccgo_" + libbase + "_fPIC"
} else {
switch GOOS {
case "darwin":
if GOARCH == "arm" || GOARCH == "arm64" {
libbase += "_shared"
}
case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris", "illumos":
libbase += "_shared"
}
}
libgodir = filepath.Join(GOPATH, "pkg", libbase, "testcarchive")
cc = append(cc, "-I", libgodir)
if GOOS == "windows" {
exeSuffix = ".exe"
}
return m.Run()
}
func goEnv(key string) string {
out, err := exec.Command("go", "env", key).Output()
if err != nil {
if ee, ok := err.(*exec.ExitError); ok {
fmt.Fprintf(os.Stderr, "%s", ee.Stderr)
}
log.Panicf("go env %s failed:\n%s\n", key, err)
}
return strings.TrimSpace(string(out))
}
func cmdToRun(name string) []string {
execScript := "go_" + goEnv("GOOS") + "_" + goEnv("GOARCH") + "_exec"
executor, err := exec.LookPath(execScript)
if err != nil {
return []string{name}
}
return []string{executor, name}
}
func testInstall(t *testing.T, exe, libgoa, libgoh string, buildcmd ...string) {
t.Helper()
cmd := exec.Command(buildcmd[0], buildcmd[1:]...)
t.Log(buildcmd)
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
defer func() {
os.Remove(libgoa)
os.Remove(libgoh)
}()
ccArgs := append(cc, "-o", exe, "main.c")
if GOOS == "windows" {
ccArgs = append(ccArgs, "main_windows.c", libgoa, "-lntdll", "-lws2_32", "-lwinmm")
} else {
ccArgs = append(ccArgs, "main_unix.c", libgoa)
}
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
t.Log(ccArgs)
if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
defer os.Remove(exe)
binArgs := append(cmdToRun(exe), "arg1", "arg2")
cmd = exec.Command(binArgs[0], binArgs[1:]...)
if runtime.Compiler == "gccgo" {
cmd.Env = append(os.Environ(), "GCCGO=1")
}
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
checkLineComments(t, libgoh)
}
var badLineRegexp = regexp.MustCompile(`(?m)^#line [0-9]+ "/.*$`)
// checkLineComments checks that the export header generated by
// -buildmode=c-archive doesn't have any absolute paths in the #line
// comments. We don't want those paths because they are unhelpful for
// the user and make the files change based on details of the location
// of GOPATH.
func checkLineComments(t *testing.T, hdrname string) {
hdr, err := ioutil.ReadFile(hdrname)
if err != nil {
if !os.IsNotExist(err) {
t.Error(err)
}
return
}
if line := badLineRegexp.Find(hdr); line != nil {
t.Errorf("bad #line directive with absolute path in %s: %q", hdrname, line)
}
}
func TestInstall(t *testing.T) {
defer os.RemoveAll(filepath.Join(GOPATH, "pkg"))
libgoa := "libgo.a"
if runtime.Compiler == "gccgo" {
libgoa = "liblibgo.a"
}
testInstall(t, "./testp1"+exeSuffix,
filepath.Join(libgodir, libgoa),
filepath.Join(libgodir, "libgo.h"),
"go", "install", "-i", "-buildmode=c-archive", "./libgo")
// Test building libgo other than installing it.
// Header files are now present.
testInstall(t, "./testp2"+exeSuffix, "libgo.a", "libgo.h",
"go", "build", "-buildmode=c-archive", filepath.Join(".", "libgo", "libgo.go"))
testInstall(t, "./testp3"+exeSuffix, "libgo.a", "libgo.h",
"go", "build", "-buildmode=c-archive", "-o", "libgo.a", "./libgo")
}
func TestEarlySignalHandler(t *testing.T) {
switch GOOS {
case "darwin":
switch GOARCH {
case "arm", "arm64":
t.Skipf("skipping on %s/%s; see https://golang.org/issue/13701", GOOS, GOARCH)
}
case "windows":
t.Skip("skipping signal test on Windows")
}
defer func() {
os.Remove("libgo2.a")
os.Remove("libgo2.h")
os.Remove("testp")
os.RemoveAll(filepath.Join(GOPATH, "pkg"))
}()
cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "./libgo2")
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
checkLineComments(t, "libgo2.h")
ccArgs := append(cc, "-o", "testp"+exeSuffix, "main2.c", "libgo2.a")
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
if out, err := exec.Command(bin[0], bin[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
}
func TestSignalForwarding(t *testing.T) {
checkSignalForwardingTest(t)
defer func() {
os.Remove("libgo2.a")
os.Remove("libgo2.h")
os.Remove("testp")
os.RemoveAll(filepath.Join(GOPATH, "pkg"))
}()
cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "./libgo2")
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
checkLineComments(t, "libgo2.h")
ccArgs := append(cc, "-o", "testp"+exeSuffix, "main5.c", "libgo2.a")
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
cmd = exec.Command(bin[0], append(bin[1:], "1")...)
out, err := cmd.CombinedOutput()
t.Logf("%s", out)
expectSignal(t, err, syscall.SIGSEGV)
// Test SIGPIPE forwarding
cmd = exec.Command(bin[0], append(bin[1:], "3")...)
out, err = cmd.CombinedOutput()
t.Logf("%s", out)
expectSignal(t, err, syscall.SIGPIPE)
}
func TestSignalForwardingExternal(t *testing.T) {
if GOOS == "freebsd" || GOOS == "aix" {
t.Skipf("skipping on %s/%s; signal always goes to the Go runtime", GOOS, GOARCH)
} else if GOOS == "darwin" && GOARCH == "amd64" {
t.Skipf("skipping on %s/%s: runtime does not permit SI_USER SIGSEGV", GOOS, GOARCH)
}
checkSignalForwardingTest(t)
defer func() {
os.Remove("libgo2.a")
os.Remove("libgo2.h")
os.Remove("testp")
os.RemoveAll(filepath.Join(GOPATH, "pkg"))
}()
cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "./libgo2")
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
checkLineComments(t, "libgo2.h")
ccArgs := append(cc, "-o", "testp"+exeSuffix, "main5.c", "libgo2.a")
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
// We want to send the process a signal and see if it dies.
// Normally the signal goes to the C thread, the Go signal
// handler picks it up, sees that it is running in a C thread,
// and the program dies. Unfortunately, occasionally the
// signal is delivered to a Go thread, which winds up
// discarding it because it was sent by another program and
// there is no Go handler for it. To avoid this, run the
// program several times in the hopes that it will eventually
// fail.
const tries = 20
for i := 0; i < tries; i++ {
cmd = exec.Command(bin[0], append(bin[1:], "2")...)
stderr, err := cmd.StderrPipe()
if err != nil {
t.Fatal(err)
}
defer stderr.Close()
r := bufio.NewReader(stderr)
err = cmd.Start()
if err != nil {
t.Fatal(err)
}
// Wait for trigger to ensure that the process is started.
ok, err := r.ReadString('\n')
// Verify trigger.
if err != nil || ok != "OK\n" {
t.Fatalf("Did not receive OK signal")
}
// Give the program a chance to enter the sleep function.
time.Sleep(time.Millisecond)
cmd.Process.Signal(syscall.SIGSEGV)
err = cmd.Wait()
if err == nil {
continue
}
if expectSignal(t, err, syscall.SIGSEGV) {
return
}
}
t.Errorf("program succeeded unexpectedly %d times", tries)
}
// checkSignalForwardingTest calls t.Skip if the SignalForwarding test
// doesn't work on this platform.
func checkSignalForwardingTest(t *testing.T) {
switch GOOS {
case "darwin":
switch GOARCH {
case "arm", "arm64":
t.Skipf("skipping on %s/%s; see https://golang.org/issue/13701", GOOS, GOARCH)
}
case "windows":
t.Skip("skipping signal test on Windows")
}
}
// expectSignal checks that err, the exit status of a test program,
// shows a failure due to a specific signal. Returns whether we found
// the expected signal.
func expectSignal(t *testing.T, err error, sig syscall.Signal) bool {
if err == nil {
t.Error("test program succeeded unexpectedly")
} else if ee, ok := err.(*exec.ExitError); !ok {
t.Errorf("error (%v) has type %T; expected exec.ExitError", err, err)
} else if ws, ok := ee.Sys().(syscall.WaitStatus); !ok {
t.Errorf("error.Sys (%v) has type %T; expected syscall.WaitStatus", ee.Sys(), ee.Sys())
} else if !ws.Signaled() || ws.Signal() != sig {
t.Errorf("got %v; expected signal %v", ee, sig)
} else {
return true
}
return false
}
func TestOsSignal(t *testing.T) {
switch GOOS {
case "windows":
t.Skip("skipping signal test on Windows")
}
defer func() {
os.Remove("libgo3.a")
os.Remove("libgo3.h")
os.Remove("testp")
os.RemoveAll(filepath.Join(GOPATH, "pkg"))
}()
cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo3.a", "./libgo3")
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
checkLineComments(t, "libgo3.h")
ccArgs := append(cc, "-o", "testp"+exeSuffix, "main3.c", "libgo3.a")
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
if out, err := exec.Command(bin[0], bin[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
}
func TestSigaltstack(t *testing.T) {
switch GOOS {
case "windows":
t.Skip("skipping signal test on Windows")
}
defer func() {
os.Remove("libgo4.a")
os.Remove("libgo4.h")
os.Remove("testp")
os.RemoveAll(filepath.Join(GOPATH, "pkg"))
}()
cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo4.a", "./libgo4")
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
checkLineComments(t, "libgo4.h")
ccArgs := append(cc, "-o", "testp"+exeSuffix, "main4.c", "libgo4.a")
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
if out, err := exec.Command(bin[0], bin[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
}
const testar = `#!/usr/bin/env bash
while [[ $1 == -* ]] >/dev/null; do
shift
done
echo "testar" > $1
echo "testar" > PWD/testar.ran
`
func TestExtar(t *testing.T) {
switch GOOS {
case "windows":
t.Skip("skipping signal test on Windows")
}
if runtime.Compiler == "gccgo" {
t.Skip("skipping -extar test when using gccgo")
}
if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
t.Skip("shell scripts are not executable on iOS hosts")
}
defer func() {
os.Remove("libgo4.a")
os.Remove("libgo4.h")
os.Remove("testar")
os.Remove("testar.ran")
os.RemoveAll(filepath.Join(GOPATH, "pkg"))
}()
os.Remove("testar")
dir, err := os.Getwd()
if err != nil {
t.Fatal(err)
}
s := strings.Replace(testar, "PWD", dir, 1)
if err := ioutil.WriteFile("testar", []byte(s), 0777); err != nil {
t.Fatal(err)
}
cmd := exec.Command("go", "build", "-buildmode=c-archive", "-ldflags=-extar="+filepath.Join(dir, "testar"), "-o", "libgo4.a", "./libgo4")
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
checkLineComments(t, "libgo4.h")
if _, err := os.Stat("testar.ran"); err != nil {
if os.IsNotExist(err) {
t.Error("testar does not exist after go build")
} else {
t.Errorf("error checking testar: %v", err)
}
}
}
func TestPIE(t *testing.T) {
switch GOOS {
case "windows", "darwin", "plan9":
t.Skipf("skipping PIE test on %s", GOOS)
}
defer func() {
os.Remove("testp" + exeSuffix)
os.RemoveAll(filepath.Join(GOPATH, "pkg"))
}()
cmd := exec.Command("go", "install", "-i", "-buildmode=c-archive", "./libgo")
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
libgoa := "libgo.a"
if runtime.Compiler == "gccgo" {
libgoa = "liblibgo.a"
}
ccArgs := append(cc, "-fPIE", "-pie", "-o", "testp"+exeSuffix, "main.c", "main_unix.c", filepath.Join(libgodir, libgoa))
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
binArgs := append(bin, "arg1", "arg2")
cmd = exec.Command(binArgs[0], binArgs[1:]...)
if runtime.Compiler == "gccgo" {
cmd.Env = append(os.Environ(), "GCCGO=1")
}
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
if GOOS != "aix" {
f, err := elf.Open("testp" + exeSuffix)
if err != nil {
t.Fatal("elf.Open failed: ", err)
}
defer f.Close()
if hasDynTag(t, f, elf.DT_TEXTREL) {
t.Errorf("%s has DT_TEXTREL flag", "testp"+exeSuffix)
}
}
}
func hasDynTag(t *testing.T, f *elf.File, tag elf.DynTag) bool {
ds := f.SectionByType(elf.SHT_DYNAMIC)
if ds == nil {
t.Error("no SHT_DYNAMIC section")
return false
}
d, err := ds.Data()
if err != nil {
t.Errorf("can't read SHT_DYNAMIC contents: %v", err)
return false
}
for len(d) > 0 {
var t elf.DynTag
switch f.Class {
case elf.ELFCLASS32:
t = elf.DynTag(f.ByteOrder.Uint32(d[:4]))
d = d[8:]
case elf.ELFCLASS64:
t = elf.DynTag(f.ByteOrder.Uint64(d[:8]))
d = d[16:]
}
if t == tag {
return true
}
}
return false
}
func TestSIGPROF(t *testing.T) {
switch GOOS {
case "windows", "plan9":
t.Skipf("skipping SIGPROF test on %s", GOOS)
case "darwin":
t.Skipf("skipping SIGPROF test on %s; see https://golang.org/issue/19320", GOOS)
}
t.Parallel()
defer func() {
os.Remove("testp6" + exeSuffix)
os.Remove("libgo6.a")
os.Remove("libgo6.h")
}()
cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo6.a", "./libgo6")
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
checkLineComments(t, "libgo6.h")
ccArgs := append(cc, "-o", "testp6"+exeSuffix, "main6.c", "libgo6.a")
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
if out, err := exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
argv := cmdToRun("./testp6")
cmd = exec.Command(argv[0], argv[1:]...)
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
}
// TestCompileWithoutShared tests that if we compile code without the
// -shared option, we can put it into an archive. When we use the go
// tool with -buildmode=c-archive, it passes -shared to the compiler,
// so we override that. The go tool doesn't work this way, but Bazel
// will likely do it in the future. And it ought to work. This test
// was added because at one time it did not work on PPC GNU/Linux.
func TestCompileWithoutShared(t *testing.T) {
// For simplicity, reuse the signal forwarding test.
checkSignalForwardingTest(t)
defer func() {
os.Remove("libgo2.a")
os.Remove("libgo2.h")
}()
cmd := exec.Command("go", "build", "-buildmode=c-archive", "-gcflags=-shared=false", "-o", "libgo2.a", "./libgo2")
t.Log(cmd.Args)
out, err := cmd.CombinedOutput()
t.Logf("%s", out)
if err != nil {
t.Fatal(err)
}
checkLineComments(t, "libgo2.h")
exe := "./testnoshared" + exeSuffix
// In some cases, -no-pie is needed here, but not accepted everywhere. First try
// if -no-pie is accepted. See #22126.
ccArgs := append(cc, "-o", exe, "-no-pie", "main5.c", "libgo2.a")
if runtime.Compiler == "gccgo" {
ccArgs = append(ccArgs, "-lgo")
}
t.Log(ccArgs)
out, err = exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput()
// If -no-pie unrecognized, try -nopie if this is possibly clang
if err != nil && bytes.Contains(out, []byte("unknown")) && !strings.Contains(cc[0], "gcc") {
ccArgs = append(cc, "-o", exe, "-nopie", "main5.c", "libgo2.a")
t.Log(ccArgs)
out, err = exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput()
}
// Don't use either -no-pie or -nopie
if err != nil && bytes.Contains(out, []byte("unrecognized")) {
ccArgs := append(cc, "-o", exe, "main5.c", "libgo2.a")
t.Log(ccArgs)
out, err = exec.Command(ccArgs[0], ccArgs[1:]...).CombinedOutput()
}
t.Logf("%s", out)
if err != nil {
t.Fatal(err)
}
defer os.Remove(exe)
binArgs := append(cmdToRun(exe), "3")
t.Log(binArgs)
out, err = exec.Command(binArgs[0], binArgs[1:]...).CombinedOutput()
t.Logf("%s", out)
expectSignal(t, err, syscall.SIGPIPE)
}
// Test that installing a second time recreates the header files.
func TestCachedInstall(t *testing.T) {
defer os.RemoveAll(filepath.Join(GOPATH, "pkg"))
h1 := filepath.Join(libgodir, "libgo.h")
h2 := filepath.Join(libgodir, "p.h")
buildcmd := []string{"go", "install", "-i", "-buildmode=c-archive", "./libgo"}
cmd := exec.Command(buildcmd[0], buildcmd[1:]...)
t.Log(buildcmd)
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
if _, err := os.Stat(h1); err != nil {
t.Errorf("libgo.h not installed: %v", err)
}
if _, err := os.Stat(h2); err != nil {
t.Errorf("p.h not installed: %v", err)
}
if err := os.Remove(h1); err != nil {
t.Fatal(err)
}
if err := os.Remove(h2); err != nil {
t.Fatal(err)
}
cmd = exec.Command(buildcmd[0], buildcmd[1:]...)
t.Log(buildcmd)
if out, err := cmd.CombinedOutput(); err != nil {
t.Logf("%s", out)
t.Fatal(err)
}
if _, err := os.Stat(h1); err != nil {
t.Errorf("libgo.h not installed in second run: %v", err)
}
if _, err := os.Stat(h2); err != nil {
t.Errorf("p.h not installed in second run: %v", err)
}
}