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
|
// Copyright 2018 The Bazel Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package main
import (
"flag"
"fmt"
"go/build"
"os"
"path/filepath"
"regexp"
"strings"
)
// stdlib builds the standard library in the appropriate mode into a new goroot.
func stdlib(args []string) error {
// process the args
flags := flag.NewFlagSet("stdlib", flag.ExitOnError)
goenv := envFlags(flags)
out := flags.String("out", "", "Path to output go root")
race := flags.Bool("race", false, "Build in race mode")
shared := flags.Bool("shared", false, "Build in shared mode")
dynlink := flags.Bool("dynlink", false, "Build in dynlink mode")
var packages multiFlag
flags.Var(&packages, "package", "Packages to build")
var gcflags quoteMultiFlag
flags.Var(&gcflags, "gcflags", "Go compiler flags")
if err := flags.Parse(args); err != nil {
return err
}
if err := goenv.checkFlags(); err != nil {
return err
}
goroot := os.Getenv("GOROOT")
if goroot == "" {
return fmt.Errorf("GOROOT not set")
}
output := abs(*out)
// Fail fast if cgo is required but a toolchain is not configured.
if os.Getenv("CGO_ENABLED") == "1" && filepath.Base(os.Getenv("CC")) == "vc_installation_error.bat" {
return fmt.Errorf(`cgo is required, but a C toolchain has not been configured.
You may need to use the flags --cpu=x64_windows --compiler=mingw-gcc.`)
}
// Link in the bare minimum needed to the new GOROOT
if err := replicate(goroot, output, replicatePaths("src", "pkg/tool", "pkg/include")); err != nil {
return err
}
output, err := processPath(output)
if err != nil {
return err
}
// Now switch to the newly created GOROOT
os.Setenv("GOROOT", output)
// Create a temporary cache directory. "go build" requires this starting
// in Go 1.12.
cachePath := filepath.Join(output, ".gocache")
os.Setenv("GOCACHE", cachePath)
defer os.RemoveAll(cachePath)
// Disable modules for the 'go install' command. Depending on the sandboxing
// mode, there may be a go.mod file in a parent directory which will turn
// modules on in "auto" mode.
os.Setenv("GO111MODULE", "off")
// Make sure we have an absolute path to the C compiler.
// TODO(#1357): also take absolute paths of includes and other paths in flags.
os.Setenv("CC", quotePathIfNeeded(abs(os.Getenv("CC"))))
// Ensure paths are absolute.
absPaths := []string{}
for _, path := range filepath.SplitList(os.Getenv("PATH")) {
absPaths = append(absPaths, abs(path))
}
os.Setenv("PATH", strings.Join(absPaths, string(os.PathListSeparator)))
sandboxPath := abs(".")
// Strip path prefix from source files in debug information.
os.Setenv("CGO_CFLAGS", os.Getenv("CGO_CFLAGS")+" "+strings.Join(defaultCFlags(output), " "))
os.Setenv("CGO_LDFLAGS", os.Getenv("CGO_LDFLAGS")+" "+strings.Join(defaultLdFlags(), " "))
// Allow flags in CGO_LDFLAGS that wouldn't pass the security check.
// Workaround for golang.org/issue/42565.
var b strings.Builder
sep := ""
cgoLdflags, _ := splitQuoted(os.Getenv("CGO_LDFLAGS"))
for _, f := range cgoLdflags {
b.WriteString(sep)
sep = "|"
b.WriteString(regexp.QuoteMeta(f))
// If the flag if -framework, the flag value needs to be in the same
// condition.
if f == "-framework" {
sep = " "
}
}
os.Setenv("CGO_LDFLAGS_ALLOW", b.String())
os.Setenv("GODEBUG", "installgoroot=all")
// Build the commands needed to build the std library in the right mode
// NOTE: the go command stamps compiled .a files with build ids, which are
// cryptographic sums derived from the inputs. This prevents us from
// creating reproducible builds because the build ids are hashed from
// CGO_CFLAGS, which frequently contains absolute paths. As a workaround,
// we strip the build ids, since they won't be used after this.
installArgs := goenv.goCmd("install", "-toolexec", abs(os.Args[0])+" filterbuildid")
if len(build.Default.BuildTags) > 0 {
installArgs = append(installArgs, "-tags", strings.Join(build.Default.BuildTags, ","))
}
ldflags := []string{"-trimpath", sandboxPath}
asmflags := []string{"-trimpath", output}
if *race {
installArgs = append(installArgs, "-race")
}
if *shared {
gcflags = append(gcflags, "-shared")
ldflags = append(ldflags, "-shared")
asmflags = append(asmflags, "-shared")
}
if *dynlink {
gcflags = append(gcflags, "-dynlink")
ldflags = append(ldflags, "-dynlink")
asmflags = append(asmflags, "-dynlink")
}
// Since Go 1.10, an all= prefix indicates the flags should apply to the package
// and its dependencies, rather than just the package itself. This was the
// default behavior before Go 1.10.
allSlug := ""
for _, t := range build.Default.ReleaseTags {
if t == "go1.10" {
allSlug = "all="
break
}
}
installArgs = append(installArgs, "-gcflags="+allSlug+strings.Join(gcflags, " "))
installArgs = append(installArgs, "-ldflags="+allSlug+strings.Join(ldflags, " "))
installArgs = append(installArgs, "-asmflags="+allSlug+strings.Join(asmflags, " "))
// Modifying CGO flags to use only absolute path
// because go is having its own sandbox, all CGO flags must use absolute path
if err := absEnv(cgoEnvVars, cgoAbsEnvFlags); err != nil {
return fmt.Errorf("error modifying cgo environment to absolute path: %v", err)
}
installArgs = append(installArgs, packages...)
if err := goenv.runCommand(installArgs); err != nil {
return err
}
return nil
}
|
