1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
|
// Copyright 2011 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 work
import (
"fmt"
exec "internal/execabs"
"os"
"path/filepath"
"strings"
"sync"
"cmd/go/internal/base"
"cmd/go/internal/cfg"
"cmd/go/internal/fsys"
"cmd/go/internal/load"
"cmd/go/internal/str"
"cmd/internal/pkgpath"
)
// The Gccgo toolchain.
type gccgoToolchain struct{}
var GccgoName, GccgoBin string
var gccgoErr error
func init() {
GccgoName = cfg.Getenv("GCCGO")
if GccgoName == "" {
GccgoName = "gccgo"
}
GccgoBin, gccgoErr = exec.LookPath(GccgoName)
}
func (gccgoToolchain) compiler() string {
checkGccgoBin()
return GccgoBin
}
func (gccgoToolchain) linker() string {
checkGccgoBin()
return GccgoBin
}
func (gccgoToolchain) ar() string {
ar := cfg.Getenv("AR")
if ar == "" {
ar = "ar"
}
return ar
}
func checkGccgoBin() {
if gccgoErr == nil {
return
}
fmt.Fprintf(os.Stderr, "cmd/go: gccgo: %s\n", gccgoErr)
base.SetExitStatus(2)
base.Exit()
}
func (tools gccgoToolchain) gc(b *Builder, a *Action, archive string, importcfg, embedcfg []byte, symabis string, asmhdr bool, gofiles []string) (ofile string, output []byte, err error) {
p := a.Package
objdir := a.Objdir
out := "_go_.o"
ofile = objdir + out
gcargs := []string{"-g"}
gcargs = append(gcargs, b.gccArchArgs()...)
gcargs = append(gcargs, "-fdebug-prefix-map="+b.WorkDir+"=/tmp/go-build")
gcargs = append(gcargs, "-gno-record-gcc-switches")
if pkgpath := gccgoPkgpath(p); pkgpath != "" {
gcargs = append(gcargs, "-fgo-pkgpath="+pkgpath)
}
if p.Internal.LocalPrefix != "" {
gcargs = append(gcargs, "-fgo-relative-import-path="+p.Internal.LocalPrefix)
}
args := str.StringList(tools.compiler(), "-c", gcargs, "-o", ofile, forcedGccgoflags)
if importcfg != nil {
if b.gccSupportsFlag(args[:1], "-fgo-importcfg=/dev/null") {
if err := b.writeFile(objdir+"importcfg", importcfg); err != nil {
return "", nil, err
}
args = append(args, "-fgo-importcfg="+objdir+"importcfg")
} else {
root := objdir + "_importcfgroot_"
if err := buildImportcfgSymlinks(b, root, importcfg); err != nil {
return "", nil, err
}
args = append(args, "-I", root)
}
}
if embedcfg != nil && b.gccSupportsFlag(args[:1], "-fgo-embedcfg=/dev/null") {
if err := b.writeFile(objdir+"embedcfg", embedcfg); err != nil {
return "", nil, err
}
args = append(args, "-fgo-embedcfg="+objdir+"embedcfg")
}
if b.gccSupportsFlag(args[:1], "-ffile-prefix-map=a=b") {
if cfg.BuildTrimpath {
args = append(args, "-ffile-prefix-map="+base.Cwd+"=.")
args = append(args, "-ffile-prefix-map="+b.WorkDir+"=/tmp/go-build")
}
if fsys.OverlayFile != "" {
for _, name := range gofiles {
absPath := mkAbs(p.Dir, name)
overlayPath, ok := fsys.OverlayPath(absPath)
if !ok {
continue
}
toPath := absPath
// gccgo only applies the last matching rule, so also handle the case where
// BuildTrimpath is true and the path is relative to base.Cwd.
if cfg.BuildTrimpath && str.HasFilePathPrefix(toPath, base.Cwd) {
toPath = "." + toPath[len(base.Cwd):]
}
args = append(args, "-ffile-prefix-map="+overlayPath+"="+toPath)
}
}
}
args = append(args, a.Package.Internal.Gccgoflags...)
for _, f := range gofiles {
f := mkAbs(p.Dir, f)
// Overlay files if necessary.
// See comment on gctoolchain.gc about overlay TODOs
f, _ = fsys.OverlayPath(f)
args = append(args, f)
}
output, err = b.runOut(a, p.Dir, nil, args)
return ofile, output, err
}
// buildImportcfgSymlinks builds in root a tree of symlinks
// implementing the directives from importcfg.
// This serves as a temporary transition mechanism until
// we can depend on gccgo reading an importcfg directly.
// (The Go 1.9 and later gc compilers already do.)
func buildImportcfgSymlinks(b *Builder, root string, importcfg []byte) error {
for lineNum, line := range strings.Split(string(importcfg), "\n") {
lineNum++ // 1-based
line = strings.TrimSpace(line)
if line == "" {
continue
}
if line == "" || strings.HasPrefix(line, "#") {
continue
}
var verb, args string
if i := strings.Index(line, " "); i < 0 {
verb = line
} else {
verb, args = line[:i], strings.TrimSpace(line[i+1:])
}
var before, after string
if i := strings.Index(args, "="); i >= 0 {
before, after = args[:i], args[i+1:]
}
switch verb {
default:
base.Fatalf("importcfg:%d: unknown directive %q", lineNum, verb)
case "packagefile":
if before == "" || after == "" {
return fmt.Errorf(`importcfg:%d: invalid packagefile: syntax is "packagefile path=filename": %s`, lineNum, line)
}
archive := gccgoArchive(root, before)
if err := b.Mkdir(filepath.Dir(archive)); err != nil {
return err
}
if err := b.Symlink(after, archive); err != nil {
return err
}
case "importmap":
if before == "" || after == "" {
return fmt.Errorf(`importcfg:%d: invalid importmap: syntax is "importmap old=new": %s`, lineNum, line)
}
beforeA := gccgoArchive(root, before)
afterA := gccgoArchive(root, after)
if err := b.Mkdir(filepath.Dir(beforeA)); err != nil {
return err
}
if err := b.Mkdir(filepath.Dir(afterA)); err != nil {
return err
}
if err := b.Symlink(afterA, beforeA); err != nil {
return err
}
case "packageshlib":
return fmt.Errorf("gccgo -importcfg does not support shared libraries")
}
}
return nil
}
func (tools gccgoToolchain) asm(b *Builder, a *Action, sfiles []string) ([]string, error) {
p := a.Package
var ofiles []string
for _, sfile := range sfiles {
base := filepath.Base(sfile)
ofile := a.Objdir + base[:len(base)-len(".s")] + ".o"
ofiles = append(ofiles, ofile)
sfile, _ = fsys.OverlayPath(mkAbs(p.Dir, sfile))
defs := []string{"-D", "GOOS_" + cfg.Goos, "-D", "GOARCH_" + cfg.Goarch}
if pkgpath := tools.gccgoCleanPkgpath(b, p); pkgpath != "" {
defs = append(defs, `-D`, `GOPKGPATH=`+pkgpath)
}
defs = tools.maybePIC(defs)
defs = append(defs, b.gccArchArgs()...)
err := b.run(a, p.Dir, p.ImportPath, nil, tools.compiler(), "-xassembler-with-cpp", "-I", a.Objdir, "-c", "-o", ofile, defs, sfile)
if err != nil {
return nil, err
}
}
return ofiles, nil
}
func (gccgoToolchain) symabis(b *Builder, a *Action, sfiles []string) (string, error) {
return "", nil
}
func gccgoArchive(basedir, imp string) string {
end := filepath.FromSlash(imp + ".a")
afile := filepath.Join(basedir, end)
// add "lib" to the final element
return filepath.Join(filepath.Dir(afile), "lib"+filepath.Base(afile))
}
func (tools gccgoToolchain) pack(b *Builder, a *Action, afile string, ofiles []string) error {
p := a.Package
objdir := a.Objdir
var absOfiles []string
for _, f := range ofiles {
absOfiles = append(absOfiles, mkAbs(objdir, f))
}
var arArgs []string
if cfg.Goos == "aix" && cfg.Goarch == "ppc64" {
// AIX puts both 32-bit and 64-bit objects in the same archive.
// Tell the AIX "ar" command to only care about 64-bit objects.
arArgs = []string{"-X64"}
}
absAfile := mkAbs(objdir, afile)
// Try with D modifier first, then without if that fails.
output, err := b.runOut(a, p.Dir, nil, tools.ar(), arArgs, "rcD", absAfile, absOfiles)
if err != nil {
return b.run(a, p.Dir, p.ImportPath, nil, tools.ar(), arArgs, "rc", absAfile, absOfiles)
}
if len(output) > 0 {
// Show the output if there is any even without errors.
b.showOutput(a, p.Dir, p.ImportPath, b.processOutput(output))
}
return nil
}
func (tools gccgoToolchain) link(b *Builder, root *Action, out, importcfg string, allactions []*Action, buildmode, desc string) error {
// gccgo needs explicit linking with all package dependencies,
// and all LDFLAGS from cgo dependencies.
afiles := []string{}
shlibs := []string{}
ldflags := b.gccArchArgs()
cgoldflags := []string{}
usesCgo := false
cxx := false
objc := false
fortran := false
if root.Package != nil {
cxx = len(root.Package.CXXFiles) > 0 || len(root.Package.SwigCXXFiles) > 0
objc = len(root.Package.MFiles) > 0
fortran = len(root.Package.FFiles) > 0
}
readCgoFlags := func(flagsFile string) error {
flags, err := os.ReadFile(flagsFile)
if err != nil {
return err
}
const ldflagsPrefix = "_CGO_LDFLAGS="
for _, line := range strings.Split(string(flags), "\n") {
if strings.HasPrefix(line, ldflagsPrefix) {
newFlags := strings.Fields(line[len(ldflagsPrefix):])
for _, flag := range newFlags {
// Every _cgo_flags file has -g and -O2 in _CGO_LDFLAGS
// but they don't mean anything to the linker so filter
// them out.
if flag != "-g" && !strings.HasPrefix(flag, "-O") {
cgoldflags = append(cgoldflags, flag)
}
}
}
}
return nil
}
var arArgs []string
if cfg.Goos == "aix" && cfg.Goarch == "ppc64" {
// AIX puts both 32-bit and 64-bit objects in the same archive.
// Tell the AIX "ar" command to only care about 64-bit objects.
arArgs = []string{"-X64"}
}
newID := 0
readAndRemoveCgoFlags := func(archive string) (string, error) {
newID++
newArchive := root.Objdir + fmt.Sprintf("_pkg%d_.a", newID)
if err := b.copyFile(newArchive, archive, 0666, false); err != nil {
return "", err
}
if cfg.BuildN || cfg.BuildX {
b.Showcmd("", "ar d %s _cgo_flags", newArchive)
if cfg.BuildN {
// TODO(rsc): We could do better about showing the right _cgo_flags even in -n mode.
// Either the archive is already built and we can read them out,
// or we're printing commands to build the archive and can
// forward the _cgo_flags directly to this step.
return "", nil
}
}
err := b.run(root, root.Objdir, desc, nil, tools.ar(), arArgs, "x", newArchive, "_cgo_flags")
if err != nil {
return "", err
}
err = b.run(root, ".", desc, nil, tools.ar(), arArgs, "d", newArchive, "_cgo_flags")
if err != nil {
return "", err
}
err = readCgoFlags(filepath.Join(root.Objdir, "_cgo_flags"))
if err != nil {
return "", err
}
return newArchive, nil
}
// If using -linkshared, find the shared library deps.
haveShlib := make(map[string]bool)
targetBase := filepath.Base(root.Target)
if cfg.BuildLinkshared {
for _, a := range root.Deps {
p := a.Package
if p == nil || p.Shlib == "" {
continue
}
// The .a we are linking into this .so
// will have its Shlib set to this .so.
// Don't start thinking we want to link
// this .so into itself.
base := filepath.Base(p.Shlib)
if base != targetBase {
haveShlib[base] = true
}
}
}
// Arrange the deps into afiles and shlibs.
addedShlib := make(map[string]bool)
for _, a := range root.Deps {
p := a.Package
if p != nil && p.Shlib != "" && haveShlib[filepath.Base(p.Shlib)] {
// This is a package linked into a shared
// library that we will put into shlibs.
continue
}
if haveShlib[filepath.Base(a.Target)] {
// This is a shared library we want to link against.
if !addedShlib[a.Target] {
shlibs = append(shlibs, a.Target)
addedShlib[a.Target] = true
}
continue
}
if p != nil {
target := a.built
if p.UsesCgo() || p.UsesSwig() {
var err error
target, err = readAndRemoveCgoFlags(target)
if err != nil {
continue
}
}
afiles = append(afiles, target)
}
}
for _, a := range allactions {
// Gather CgoLDFLAGS, but not from standard packages.
// The go tool can dig up runtime/cgo from GOROOT and
// think that it should use its CgoLDFLAGS, but gccgo
// doesn't use runtime/cgo.
if a.Package == nil {
continue
}
if !a.Package.Standard {
cgoldflags = append(cgoldflags, a.Package.CgoLDFLAGS...)
}
if len(a.Package.CgoFiles) > 0 {
usesCgo = true
}
if a.Package.UsesSwig() {
usesCgo = true
}
if len(a.Package.CXXFiles) > 0 || len(a.Package.SwigCXXFiles) > 0 {
cxx = true
}
if len(a.Package.MFiles) > 0 {
objc = true
}
if len(a.Package.FFiles) > 0 {
fortran = true
}
}
wholeArchive := []string{"-Wl,--whole-archive"}
noWholeArchive := []string{"-Wl,--no-whole-archive"}
if cfg.Goos == "aix" {
wholeArchive = nil
noWholeArchive = nil
}
ldflags = append(ldflags, wholeArchive...)
ldflags = append(ldflags, afiles...)
ldflags = append(ldflags, noWholeArchive...)
ldflags = append(ldflags, cgoldflags...)
ldflags = append(ldflags, envList("CGO_LDFLAGS", "")...)
if root.Package != nil {
ldflags = append(ldflags, root.Package.CgoLDFLAGS...)
}
if cfg.Goos != "aix" {
ldflags = str.StringList("-Wl,-(", ldflags, "-Wl,-)")
}
if root.buildID != "" {
// On systems that normally use gold or the GNU linker,
// use the --build-id option to write a GNU build ID note.
switch cfg.Goos {
case "android", "dragonfly", "linux", "netbsd":
ldflags = append(ldflags, fmt.Sprintf("-Wl,--build-id=0x%x", root.buildID))
}
}
var rLibPath string
if cfg.Goos == "aix" {
rLibPath = "-Wl,-blibpath="
} else {
rLibPath = "-Wl,-rpath="
}
for _, shlib := range shlibs {
ldflags = append(
ldflags,
"-L"+filepath.Dir(shlib),
rLibPath+filepath.Dir(shlib),
"-l"+strings.TrimSuffix(
strings.TrimPrefix(filepath.Base(shlib), "lib"),
".so"))
}
var realOut string
goLibBegin := str.StringList(wholeArchive, "-lgolibbegin", noWholeArchive)
switch buildmode {
case "exe":
if usesCgo && cfg.Goos == "linux" {
ldflags = append(ldflags, "-Wl,-E")
}
case "c-archive":
// Link the Go files into a single .o, and also link
// in -lgolibbegin.
//
// We need to use --whole-archive with -lgolibbegin
// because it doesn't define any symbols that will
// cause the contents to be pulled in; it's just
// initialization code.
//
// The user remains responsible for linking against
// -lgo -lpthread -lm in the final link. We can't use
// -r to pick them up because we can't combine
// split-stack and non-split-stack code in a single -r
// link, and libgo picks up non-split-stack code from
// libffi.
ldflags = append(ldflags, "-Wl,-r", "-nostdlib")
ldflags = append(ldflags, goLibBegin...)
if nopie := b.gccNoPie([]string{tools.linker()}); nopie != "" {
ldflags = append(ldflags, nopie)
}
// We are creating an object file, so we don't want a build ID.
if root.buildID == "" {
ldflags = b.disableBuildID(ldflags)
}
realOut = out
out = out + ".o"
case "c-shared":
ldflags = append(ldflags, "-shared", "-nostdlib")
ldflags = append(ldflags, goLibBegin...)
ldflags = append(ldflags, "-lgo", "-lgcc_s", "-lgcc", "-lc", "-lgcc")
case "shared":
if cfg.Goos != "aix" {
ldflags = append(ldflags, "-zdefs")
}
ldflags = append(ldflags, "-shared", "-nostdlib", "-lgo", "-lgcc_s", "-lgcc", "-lc")
default:
base.Fatalf("-buildmode=%s not supported for gccgo", buildmode)
}
switch buildmode {
case "exe", "c-shared":
if cxx {
ldflags = append(ldflags, "-lstdc++")
}
if objc {
ldflags = append(ldflags, "-lobjc")
}
if fortran {
fc := cfg.Getenv("FC")
if fc == "" {
fc = "gfortran"
}
// support gfortran out of the box and let others pass the correct link options
// via CGO_LDFLAGS
if strings.Contains(fc, "gfortran") {
ldflags = append(ldflags, "-lgfortran")
}
}
}
if err := b.run(root, ".", desc, nil, tools.linker(), "-o", out, ldflags, forcedGccgoflags, root.Package.Internal.Gccgoflags); err != nil {
return err
}
switch buildmode {
case "c-archive":
if err := b.run(root, ".", desc, nil, tools.ar(), arArgs, "rc", realOut, out); err != nil {
return err
}
}
return nil
}
func (tools gccgoToolchain) ld(b *Builder, root *Action, out, importcfg, mainpkg string) error {
return tools.link(b, root, out, importcfg, root.Deps, ldBuildmode, root.Package.ImportPath)
}
func (tools gccgoToolchain) ldShared(b *Builder, root *Action, toplevelactions []*Action, out, importcfg string, allactions []*Action) error {
return tools.link(b, root, out, importcfg, allactions, "shared", out)
}
func (tools gccgoToolchain) cc(b *Builder, a *Action, ofile, cfile string) error {
p := a.Package
inc := filepath.Join(cfg.GOROOT, "pkg", "include")
cfile = mkAbs(p.Dir, cfile)
defs := []string{"-D", "GOOS_" + cfg.Goos, "-D", "GOARCH_" + cfg.Goarch}
defs = append(defs, b.gccArchArgs()...)
if pkgpath := tools.gccgoCleanPkgpath(b, p); pkgpath != "" {
defs = append(defs, `-D`, `GOPKGPATH="`+pkgpath+`"`)
}
compiler := envList("CC", cfg.DefaultCC(cfg.Goos, cfg.Goarch))
if b.gccSupportsFlag(compiler, "-fsplit-stack") {
defs = append(defs, "-fsplit-stack")
}
defs = tools.maybePIC(defs)
if b.gccSupportsFlag(compiler, "-ffile-prefix-map=a=b") {
defs = append(defs, "-ffile-prefix-map="+base.Cwd+"=.")
defs = append(defs, "-ffile-prefix-map="+b.WorkDir+"=/tmp/go-build")
} else if b.gccSupportsFlag(compiler, "-fdebug-prefix-map=a=b") {
defs = append(defs, "-fdebug-prefix-map="+b.WorkDir+"=/tmp/go-build")
}
if b.gccSupportsFlag(compiler, "-gno-record-gcc-switches") {
defs = append(defs, "-gno-record-gcc-switches")
}
return b.run(a, p.Dir, p.ImportPath, nil, compiler, "-Wall", "-g",
"-I", a.Objdir, "-I", inc, "-o", ofile, defs, "-c", cfile)
}
// maybePIC adds -fPIC to the list of arguments if needed.
func (tools gccgoToolchain) maybePIC(args []string) []string {
switch cfg.BuildBuildmode {
case "c-shared", "shared", "plugin":
args = append(args, "-fPIC")
}
return args
}
func gccgoPkgpath(p *load.Package) string {
if p.Internal.Build.IsCommand() && !p.Internal.ForceLibrary {
return ""
}
return p.ImportPath
}
var gccgoToSymbolFuncOnce sync.Once
var gccgoToSymbolFunc func(string) string
func (tools gccgoToolchain) gccgoCleanPkgpath(b *Builder, p *load.Package) string {
gccgoToSymbolFuncOnce.Do(func() {
fn, err := pkgpath.ToSymbolFunc(tools.compiler(), b.WorkDir)
if err != nil {
fmt.Fprintf(os.Stderr, "cmd/go: %v\n", err)
base.SetExitStatus(2)
base.Exit()
}
gccgoToSymbolFunc = fn
})
return gccgoToSymbolFunc(gccgoPkgpath(p))
}
|