blob: f0766e511ec5b3e60f9365afa5d2154793d8349c [file] [log] [blame]
// Copyright 2015 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 shared_test
import (
"bufio"
"bytes"
"debug/elf"
"encoding/binary"
"errors"
"flag"
"fmt"
"go/build"
"io"
"io/ioutil"
"log"
"math/rand"
"os"
"os/exec"
"path/filepath"
"regexp"
"runtime"
"strings"
"testing"
"time"
)
var gopathInstallDir, gorootInstallDir, suffix string
// This is the smallest set of packages we can link into a shared
// library (runtime/cgo is built implicitly).
var minpkgs = []string{"runtime", "sync/atomic"}
var soname = "libruntime,sync-atomic.so"
// run runs a command and calls t.Errorf if it fails.
func run(t *testing.T, msg string, args ...string) {
c := exec.Command(args[0], args[1:]...)
if output, err := c.CombinedOutput(); err != nil {
t.Errorf("executing %s (%s) failed %s:\n%s", strings.Join(args, " "), msg, err, output)
}
}
// goCmd invokes the go tool with the installsuffix set up by TestMain. It calls
// t.Fatalf if the command fails.
func goCmd(t *testing.T, args ...string) {
newargs := []string{args[0], "-installsuffix=" + suffix}
if testing.Verbose() {
newargs = append(newargs, "-v")
}
newargs = append(newargs, args[1:]...)
c := exec.Command("go", newargs...)
var output []byte
var err error
if testing.Verbose() {
fmt.Printf("+ go %s\n", strings.Join(newargs, " "))
c.Stdout = os.Stdout
c.Stderr = os.Stderr
err = c.Run()
} else {
output, err = c.CombinedOutput()
}
if err != nil {
if t != nil {
t.Fatalf("executing %s failed %v:\n%s", strings.Join(c.Args, " "), err, output)
} else {
log.Fatalf("executing %s failed %v:\n%s", strings.Join(c.Args, " "), err, output)
}
}
}
// TestMain calls testMain so that the latter can use defer (TestMain exits with os.Exit).
func testMain(m *testing.M) (int, error) {
// Because go install -buildmode=shared $standard_library_package always
// installs into $GOROOT, here are some gymnastics to come up with a unique
// installsuffix to use in this test that we can clean up afterwards.
myContext := build.Default
runtimeP, err := myContext.Import("runtime", ".", build.ImportComment)
if err != nil {
return 0, fmt.Errorf("import failed: %v", err)
}
for i := 0; i < 10000; i++ {
try := fmt.Sprintf("%s_%d_dynlink", runtimeP.PkgTargetRoot, rand.Int63())
err = os.Mkdir(try, 0700)
if os.IsExist(err) {
continue
}
if err == nil {
gorootInstallDir = try
}
break
}
if err != nil {
return 0, fmt.Errorf("can't create temporary directory: %v", err)
}
if gorootInstallDir == "" {
return 0, errors.New("could not create temporary directory after 10000 tries")
}
if testing.Verbose() {
fmt.Printf("+ mkdir -p %s\n", gorootInstallDir)
}
defer os.RemoveAll(gorootInstallDir)
// Some tests need to edit the source in GOPATH, so copy this directory to a
// temporary directory and chdir to that.
scratchDir, err := ioutil.TempDir("", "testshared")
if err != nil {
return 0, fmt.Errorf("TempDir failed: %v", err)
}
if testing.Verbose() {
fmt.Printf("+ mkdir -p %s\n", scratchDir)
}
defer os.RemoveAll(scratchDir)
err = filepath.Walk(".", func(path string, info os.FileInfo, err error) error {
scratchPath := filepath.Join(scratchDir, path)
if info.IsDir() {
if path == "." {
return nil
}
if testing.Verbose() {
fmt.Printf("+ mkdir -p %s\n", scratchPath)
}
return os.Mkdir(scratchPath, info.Mode())
} else {
fromBytes, err := ioutil.ReadFile(path)
if err != nil {
return err
}
if testing.Verbose() {
fmt.Printf("+ cp %s %s\n", path, scratchPath)
}
return ioutil.WriteFile(scratchPath, fromBytes, info.Mode())
}
})
if err != nil {
return 0, fmt.Errorf("walk failed: %v", err)
}
os.Setenv("GOPATH", scratchDir)
if testing.Verbose() {
fmt.Printf("+ export GOPATH=%s\n", scratchDir)
}
myContext.GOPATH = scratchDir
if testing.Verbose() {
fmt.Printf("+ cd %s\n", scratchDir)
}
os.Chdir(scratchDir)
// All tests depend on runtime being built into a shared library. Because
// that takes a few seconds, do it here and have all tests use the version
// built here.
suffix = strings.Split(filepath.Base(gorootInstallDir), "_")[2]
goCmd(nil, append([]string{"install", "-buildmode=shared"}, minpkgs...)...)
myContext.InstallSuffix = suffix + "_dynlink"
depP, err := myContext.Import("depBase", ".", build.ImportComment)
if err != nil {
return 0, fmt.Errorf("import failed: %v", err)
}
gopathInstallDir = depP.PkgTargetRoot
return m.Run(), nil
}
func TestMain(m *testing.M) {
// Some of the tests install binaries into a custom GOPATH.
// That won't work if GOBIN is set.
os.Unsetenv("GOBIN")
flag.Parse()
exitCode, err := testMain(m)
if err != nil {
log.Fatal(err)
}
os.Exit(exitCode)
}
// The shared library was built at the expected location.
func TestSOBuilt(t *testing.T) {
_, err := os.Stat(filepath.Join(gorootInstallDir, soname))
if err != nil {
t.Error(err)
}
}
func hasDynTag(f *elf.File, tag elf.DynTag) bool {
ds := f.SectionByType(elf.SHT_DYNAMIC)
if ds == nil {
return false
}
d, err := ds.Data()
if err != nil {
return false
}
for len(d) > 0 {
var t elf.DynTag
switch f.Class {
case elf.ELFCLASS32:
t = elf.DynTag(f.ByteOrder.Uint32(d[0:4]))
d = d[8:]
case elf.ELFCLASS64:
t = elf.DynTag(f.ByteOrder.Uint64(d[0:8]))
d = d[16:]
}
if t == tag {
return true
}
}
return false
}
// The shared library does not have relocations against the text segment.
func TestNoTextrel(t *testing.T) {
sopath := filepath.Join(gorootInstallDir, soname)
f, err := elf.Open(sopath)
if err != nil {
t.Fatal("elf.Open failed: ", err)
}
defer f.Close()
if hasDynTag(f, elf.DT_TEXTREL) {
t.Errorf("%s has DT_TEXTREL set", soname)
}
}
// The shared library does not contain symbols called ".dup"
func TestNoDupSymbols(t *testing.T) {
sopath := filepath.Join(gorootInstallDir, soname)
f, err := elf.Open(sopath)
if err != nil {
t.Fatal("elf.Open failed: ", err)
}
defer f.Close()
syms, err := f.Symbols()
if err != nil {
t.Errorf("error reading symbols %v", err)
return
}
for _, s := range syms {
if s.Name == ".dup" {
t.Fatalf("%s contains symbol called .dup", sopath)
}
}
}
// The install command should have created a "shlibname" file for the
// listed packages (and runtime/cgo, and math on arm) indicating the
// name of the shared library containing it.
func TestShlibnameFiles(t *testing.T) {
pkgs := append([]string{}, minpkgs...)
pkgs = append(pkgs, "runtime/cgo")
if runtime.GOARCH == "arm" {
pkgs = append(pkgs, "math")
}
for _, pkg := range pkgs {
shlibnamefile := filepath.Join(gorootInstallDir, pkg+".shlibname")
contentsb, err := ioutil.ReadFile(shlibnamefile)
if err != nil {
t.Errorf("error reading shlibnamefile for %s: %v", pkg, err)
continue
}
contents := strings.TrimSpace(string(contentsb))
if contents != soname {
t.Errorf("shlibnamefile for %s has wrong contents: %q", pkg, contents)
}
}
}
// Is a given offset into the file contained in a loaded segment?
func isOffsetLoaded(f *elf.File, offset uint64) bool {
for _, prog := range f.Progs {
if prog.Type == elf.PT_LOAD {
if prog.Off <= offset && offset < prog.Off+prog.Filesz {
return true
}
}
}
return false
}
func rnd(v int32, r int32) int32 {
if r <= 0 {
return v
}
v += r - 1
c := v % r
if c < 0 {
c += r
}
v -= c
return v
}
func readwithpad(r io.Reader, sz int32) ([]byte, error) {
data := make([]byte, rnd(sz, 4))
_, err := io.ReadFull(r, data)
if err != nil {
return nil, err
}
data = data[:sz]
return data, nil
}
type note struct {
name string
tag int32
desc string
section *elf.Section
}
// Read all notes from f. As ELF section names are not supposed to be special, one
// looks for a particular note by scanning all SHT_NOTE sections looking for a note
// with a particular "name" and "tag".
func readNotes(f *elf.File) ([]*note, error) {
var notes []*note
for _, sect := range f.Sections {
if sect.Type != elf.SHT_NOTE {
continue
}
r := sect.Open()
for {
var namesize, descsize, tag int32
err := binary.Read(r, f.ByteOrder, &namesize)
if err != nil {
if err == io.EOF {
break
}
return nil, fmt.Errorf("read namesize failed: %v", err)
}
err = binary.Read(r, f.ByteOrder, &descsize)
if err != nil {
return nil, fmt.Errorf("read descsize failed: %v", err)
}
err = binary.Read(r, f.ByteOrder, &tag)
if err != nil {
return nil, fmt.Errorf("read type failed: %v", err)
}
name, err := readwithpad(r, namesize)
if err != nil {
return nil, fmt.Errorf("read name failed: %v", err)
}
desc, err := readwithpad(r, descsize)
if err != nil {
return nil, fmt.Errorf("read desc failed: %v", err)
}
notes = append(notes, &note{name: string(name), tag: tag, desc: string(desc), section: sect})
}
}
return notes, nil
}
func dynStrings(t *testing.T, path string, flag elf.DynTag) []string {
f, err := elf.Open(path)
defer f.Close()
if err != nil {
t.Fatalf("elf.Open(%q) failed: %v", path, err)
}
dynstrings, err := f.DynString(flag)
if err != nil {
t.Fatalf("DynString(%s) failed on %s: %v", flag, path, err)
}
return dynstrings
}
func AssertIsLinkedToRegexp(t *testing.T, path string, re *regexp.Regexp) {
for _, dynstring := range dynStrings(t, path, elf.DT_NEEDED) {
if re.MatchString(dynstring) {
return
}
}
t.Errorf("%s is not linked to anything matching %v", path, re)
}
func AssertIsLinkedTo(t *testing.T, path, lib string) {
AssertIsLinkedToRegexp(t, path, regexp.MustCompile(regexp.QuoteMeta(lib)))
}
func AssertHasRPath(t *testing.T, path, dir string) {
for _, tag := range []elf.DynTag{elf.DT_RPATH, elf.DT_RUNPATH} {
for _, dynstring := range dynStrings(t, path, tag) {
for _, rpath := range strings.Split(dynstring, ":") {
if filepath.Clean(rpath) == filepath.Clean(dir) {
return
}
}
}
}
t.Errorf("%s does not have rpath %s", path, dir)
}
// Build a trivial program that links against the shared runtime and check it runs.
func TestTrivialExecutable(t *testing.T) {
goCmd(t, "install", "-linkshared", "trivial")
run(t, "trivial executable", "./bin/trivial")
AssertIsLinkedTo(t, "./bin/trivial", soname)
AssertHasRPath(t, "./bin/trivial", gorootInstallDir)
}
// Build a trivial program in PIE mode that links against the shared runtime and check it runs.
func TestTrivialExecutablePIE(t *testing.T) {
goCmd(t, "build", "-buildmode=pie", "-o", "trivial.pie", "-linkshared", "trivial")
run(t, "trivial executable", "./trivial.pie")
AssertIsLinkedTo(t, "./trivial.pie", soname)
AssertHasRPath(t, "./trivial.pie", gorootInstallDir)
}
// Build an executable that uses cgo linked against the shared runtime and check it
// runs.
func TestCgoExecutable(t *testing.T) {
goCmd(t, "install", "-linkshared", "execgo")
run(t, "cgo executable", "./bin/execgo")
}
func checkPIE(t *testing.T, name string) {
f, err := elf.Open(name)
if err != nil {
t.Fatal("elf.Open failed: ", err)
}
defer f.Close()
if f.Type != elf.ET_DYN {
t.Errorf("%s has type %v, want ET_DYN", name, f.Type)
}
if hasDynTag(f, elf.DT_TEXTREL) {
t.Errorf("%s has DT_TEXTREL set", name)
}
}
func TestTrivialPIE(t *testing.T) {
name := "trivial_pie"
goCmd(t, "build", "-buildmode=pie", "-o="+name, "trivial")
defer os.Remove(name)
run(t, name, "./"+name)
checkPIE(t, name)
}
func TestCgoPIE(t *testing.T) {
name := "cgo_pie"
goCmd(t, "build", "-buildmode=pie", "-o="+name, "execgo")
defer os.Remove(name)
run(t, name, "./"+name)
checkPIE(t, name)
}
// Build a GOPATH package into a shared library that links against the goroot runtime
// and an executable that links against both.
func TestGopathShlib(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
AssertIsLinkedTo(t, filepath.Join(gopathInstallDir, "libdepBase.so"), soname)
goCmd(t, "install", "-linkshared", "exe")
AssertIsLinkedTo(t, "./bin/exe", soname)
AssertIsLinkedTo(t, "./bin/exe", "libdepBase.so")
AssertHasRPath(t, "./bin/exe", gorootInstallDir)
AssertHasRPath(t, "./bin/exe", gopathInstallDir)
// And check it runs.
run(t, "executable linked to GOPATH library", "./bin/exe")
}
// The shared library contains a note listing the packages it contains in a section
// that is not mapped into memory.
func testPkgListNote(t *testing.T, f *elf.File, note *note) {
if note.section.Flags != 0 {
t.Errorf("package list section has flags %v", note.section.Flags)
}
if isOffsetLoaded(f, note.section.Offset) {
t.Errorf("package list section contained in PT_LOAD segment")
}
if note.desc != "depBase\n" {
t.Errorf("incorrect package list %q", note.desc)
}
}
// The shared library contains a note containing the ABI hash that is mapped into
// memory and there is a local symbol called go.link.abihashbytes that points 16
// bytes into it.
func testABIHashNote(t *testing.T, f *elf.File, note *note) {
if note.section.Flags != elf.SHF_ALLOC {
t.Errorf("abi hash section has flags %v", note.section.Flags)
}
if !isOffsetLoaded(f, note.section.Offset) {
t.Errorf("abihash section not contained in PT_LOAD segment")
}
var hashbytes elf.Symbol
symbols, err := f.Symbols()
if err != nil {
t.Errorf("error reading symbols %v", err)
return
}
for _, sym := range symbols {
if sym.Name == "go.link.abihashbytes" {
hashbytes = sym
}
}
if hashbytes.Name == "" {
t.Errorf("no symbol called go.link.abihashbytes")
return
}
if elf.ST_BIND(hashbytes.Info) != elf.STB_LOCAL {
t.Errorf("%s has incorrect binding %v", hashbytes.Name, elf.ST_BIND(hashbytes.Info))
}
if f.Sections[hashbytes.Section] != note.section {
t.Errorf("%s has incorrect section %v", hashbytes.Name, f.Sections[hashbytes.Section].Name)
}
if hashbytes.Value-note.section.Addr != 16 {
t.Errorf("%s has incorrect offset into section %d", hashbytes.Name, hashbytes.Value-note.section.Addr)
}
}
// A Go shared library contains a note indicating which other Go shared libraries it
// was linked against in an unmapped section.
func testDepsNote(t *testing.T, f *elf.File, note *note) {
if note.section.Flags != 0 {
t.Errorf("package list section has flags %v", note.section.Flags)
}
if isOffsetLoaded(f, note.section.Offset) {
t.Errorf("package list section contained in PT_LOAD segment")
}
// libdepBase.so just links against the lib containing the runtime.
if note.desc != soname {
t.Errorf("incorrect dependency list %q", note.desc)
}
}
// The shared library contains notes with defined contents; see above.
func TestNotes(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
f, err := elf.Open(filepath.Join(gopathInstallDir, "libdepBase.so"))
if err != nil {
t.Fatal(err)
}
defer f.Close()
notes, err := readNotes(f)
if err != nil {
t.Fatal(err)
}
pkgListNoteFound := false
abiHashNoteFound := false
depsNoteFound := false
for _, note := range notes {
if note.name != "Go\x00\x00" {
continue
}
switch note.tag {
case 1: // ELF_NOTE_GOPKGLIST_TAG
if pkgListNoteFound {
t.Error("multiple package list notes")
}
testPkgListNote(t, f, note)
pkgListNoteFound = true
case 2: // ELF_NOTE_GOABIHASH_TAG
if abiHashNoteFound {
t.Error("multiple abi hash notes")
}
testABIHashNote(t, f, note)
abiHashNoteFound = true
case 3: // ELF_NOTE_GODEPS_TAG
if depsNoteFound {
t.Error("multiple abi hash notes")
}
testDepsNote(t, f, note)
depsNoteFound = true
}
}
if !pkgListNoteFound {
t.Error("package list note not found")
}
if !abiHashNoteFound {
t.Error("abi hash note not found")
}
if !depsNoteFound {
t.Error("deps note not found")
}
}
// Build a GOPATH package (depBase) into a shared library that links against the goroot
// runtime, another package (dep2) that links against the first, and and an
// executable that links against dep2.
func TestTwoGopathShlibs(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep2")
goCmd(t, "install", "-linkshared", "exe2")
run(t, "executable linked to GOPATH library", "./bin/exe2")
}
func TestThreeGopathShlibs(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep2")
goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep3")
goCmd(t, "install", "-linkshared", "exe3")
run(t, "executable linked to GOPATH library", "./bin/exe3")
}
// If gccgo is not available or not new enough call t.Skip. Otherwise,
// return a build.Context that is set up for gccgo.
func prepGccgo(t *testing.T) build.Context {
gccgoName := os.Getenv("GCCGO")
if gccgoName == "" {
gccgoName = "gccgo"
}
gccgoPath, err := exec.LookPath(gccgoName)
if err != nil {
t.Skip("gccgo not found")
}
cmd := exec.Command(gccgoPath, "-dumpversion")
output, err := cmd.CombinedOutput()
if err != nil {
t.Fatalf("%s -dumpversion failed: %v\n%s", gccgoPath, err, output)
}
if string(output) < "5" {
t.Skipf("gccgo too old (%s)", strings.TrimSpace(string(output)))
}
gccgoContext := build.Default
gccgoContext.InstallSuffix = suffix + "_fPIC"
gccgoContext.Compiler = "gccgo"
gccgoContext.GOPATH = os.Getenv("GOPATH")
return gccgoContext
}
// Build a GOPATH package into a shared library with gccgo and an executable that
// links against it.
func TestGoPathShlibGccgo(t *testing.T) {
gccgoContext := prepGccgo(t)
libgoRE := regexp.MustCompile("libgo.so.[0-9]+")
depP, err := gccgoContext.Import("depBase", ".", build.ImportComment)
if err != nil {
t.Fatalf("import failed: %v", err)
}
gccgoInstallDir := filepath.Join(depP.PkgTargetRoot, "shlibs")
goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "depBase")
AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdepBase.so"), libgoRE)
goCmd(t, "install", "-compiler=gccgo", "-linkshared", "exe")
AssertIsLinkedToRegexp(t, "./bin/exe", libgoRE)
AssertIsLinkedTo(t, "./bin/exe", "libdepBase.so")
AssertHasRPath(t, "./bin/exe", gccgoInstallDir)
// And check it runs.
run(t, "gccgo-built", "./bin/exe")
}
// The gccgo version of TestTwoGopathShlibs: build a GOPATH package into a shared
// library with gccgo, another GOPATH package that depends on the first and an
// executable that links the second library.
func TestTwoGopathShlibsGccgo(t *testing.T) {
gccgoContext := prepGccgo(t)
libgoRE := regexp.MustCompile("libgo.so.[0-9]+")
depP, err := gccgoContext.Import("depBase", ".", build.ImportComment)
if err != nil {
t.Fatalf("import failed: %v", err)
}
gccgoInstallDir := filepath.Join(depP.PkgTargetRoot, "shlibs")
goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "depBase")
goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "dep2")
goCmd(t, "install", "-compiler=gccgo", "-linkshared", "exe2")
AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdepBase.so"), libgoRE)
AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdep2.so"), libgoRE)
AssertIsLinkedTo(t, filepath.Join(gccgoInstallDir, "libdep2.so"), "libdepBase.so")
AssertIsLinkedToRegexp(t, "./bin/exe2", libgoRE)
AssertIsLinkedTo(t, "./bin/exe2", "libdep2")
AssertIsLinkedTo(t, "./bin/exe2", "libdepBase.so")
// And check it runs.
run(t, "gccgo-built", "./bin/exe2")
}
// Testing rebuilding of shared libraries when they are stale is a bit more
// complicated that it seems like it should be. First, we make everything "old": but
// only a few seconds old, or it might be older than gc (or the runtime source) and
// everything will get rebuilt. Then define a timestamp slightly newer than this
// time, which is what we set the mtime to of a file to cause it to be seen as new,
// and finally another slightly even newer one that we can compare files against to
// see if they have been rebuilt.
var oldTime = time.Now().Add(-9 * time.Second)
var nearlyNew = time.Now().Add(-6 * time.Second)
var stampTime = time.Now().Add(-3 * time.Second)
// resetFileStamps makes "everything" (bin, src, pkg from GOPATH and the
// test-specific parts of GOROOT) appear old.
func resetFileStamps() {
chtime := func(path string, info os.FileInfo, err error) error {
return os.Chtimes(path, oldTime, oldTime)
}
reset := func(path string) {
if err := filepath.Walk(path, chtime); err != nil {
log.Fatalf("resetFileStamps failed: %v", err)
}
}
reset("bin")
reset("pkg")
reset("src")
reset(gorootInstallDir)
}
// touch makes path newer than the "old" time stamp used by resetFileStamps.
func touch(path string) {
if err := os.Chtimes(path, nearlyNew, nearlyNew); err != nil {
log.Fatalf("os.Chtimes failed: %v", err)
}
}
// isNew returns if the path is newer than the time stamp used by touch.
func isNew(path string) bool {
fi, err := os.Stat(path)
if err != nil {
log.Fatalf("os.Stat failed: %v", err)
}
return fi.ModTime().After(stampTime)
}
// Fail unless path has been rebuilt (i.e. is newer than the time stamp used by
// isNew)
func AssertRebuilt(t *testing.T, msg, path string) {
if !isNew(path) {
t.Errorf("%s was not rebuilt (%s)", msg, path)
}
}
// Fail if path has been rebuilt (i.e. is newer than the time stamp used by isNew)
func AssertNotRebuilt(t *testing.T, msg, path string) {
if isNew(path) {
t.Errorf("%s was rebuilt (%s)", msg, path)
}
}
func TestRebuilding(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
goCmd(t, "install", "-linkshared", "exe")
// If the source is newer than both the .a file and the .so, both are rebuilt.
resetFileStamps()
touch("src/depBase/dep.go")
goCmd(t, "install", "-linkshared", "exe")
AssertRebuilt(t, "new source", filepath.Join(gopathInstallDir, "depBase.a"))
AssertRebuilt(t, "new source", filepath.Join(gopathInstallDir, "libdepBase.so"))
// If the .a file is newer than the .so, the .so is rebuilt (but not the .a)
resetFileStamps()
touch(filepath.Join(gopathInstallDir, "depBase.a"))
goCmd(t, "install", "-linkshared", "exe")
AssertNotRebuilt(t, "new .a file", filepath.Join(gopathInstallDir, "depBase.a"))
AssertRebuilt(t, "new .a file", filepath.Join(gopathInstallDir, "libdepBase.so"))
}
func appendFile(path, content string) {
f, err := os.OpenFile(path, os.O_WRONLY|os.O_APPEND, 0660)
if err != nil {
log.Fatalf("os.OpenFile failed: %v", err)
}
defer func() {
err := f.Close()
if err != nil {
log.Fatalf("f.Close failed: %v", err)
}
}()
_, err = f.WriteString(content)
if err != nil {
log.Fatalf("f.WriteString failed: %v", err)
}
}
func TestABIChecking(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
goCmd(t, "install", "-linkshared", "exe")
// If we make an ABI-breaking change to depBase and rebuild libp.so but not exe,
// exe will abort with a complaint on startup.
// This assumes adding an exported function breaks ABI, which is not true in
// some senses but suffices for the narrow definition of ABI compatibility the
// toolchain uses today.
resetFileStamps()
appendFile("src/depBase/dep.go", "func ABIBreak() {}\n")
goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
c := exec.Command("./bin/exe")
output, err := c.CombinedOutput()
if err == nil {
t.Fatal("executing exe did not fail after ABI break")
}
scanner := bufio.NewScanner(bytes.NewReader(output))
foundMsg := false
const wantLine = "abi mismatch detected between the executable and libdepBase.so"
for scanner.Scan() {
if scanner.Text() == wantLine {
foundMsg = true
break
}
}
if err = scanner.Err(); err != nil {
t.Errorf("scanner encountered error: %v", err)
}
if !foundMsg {
t.Fatalf("exe failed, but without line %q; got output:\n%s", wantLine, output)
}
// Rebuilding exe makes it work again.
goCmd(t, "install", "-linkshared", "exe")
run(t, "rebuilt exe", "./bin/exe")
// If we make a change which does not break ABI (such as adding an unexported
// function) and rebuild libdepBase.so, exe still works.
resetFileStamps()
appendFile("src/depBase/dep.go", "func noABIBreak() {}\n")
goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
run(t, "after non-ABI breaking change", "./bin/exe")
}
// If a package 'explicit' imports a package 'implicit', building
// 'explicit' into a shared library implicitly includes implicit in
// the shared library. Building an executable that imports both
// explicit and implicit builds the code from implicit into the
// executable rather than fetching it from the shared library. The
// link still succeeds and the executable still runs though.
func TestImplicitInclusion(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "explicit")
goCmd(t, "install", "-linkshared", "implicitcmd")
run(t, "running executable linked against library that contains same package as it", "./bin/implicitcmd")
}
// Tests to make sure that the type fields of empty interfaces and itab
// fields of nonempty interfaces are unique even across modules,
// so that interface equality works correctly.
func TestInterface(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "iface_a")
// Note: iface_i gets installed implicitly as a dependency of iface_a.
goCmd(t, "install", "-buildmode=shared", "-linkshared", "iface_b")
goCmd(t, "install", "-linkshared", "iface")
run(t, "running type/itab uniqueness tester", "./bin/iface")
}