cmd/go: allow the user to specify ar via an environment variable

This allows one to customize which ar to use by fetching its path
from the environment. This way one can swap it out for a
different implementation.

Change-Id: I40d8cbd8a69e97b5254e66081d9bf0b726c10366
GitHub-Last-Rev: 4aa1d631eaca58be6c3a4be40f7404fa75a0db25
GitHub-Pull-Request: golang/go#28746
Reviewed-on: https://go-review.googlesource.com/c/149117
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index f8c4d2ffa912f43652333433b49f39b1c952fdce..e7412f9bc7c5154e593d5de291447ba8303fcf30 100644 (file)
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -1500,6 +1500,10 @@
 //             The command to use to compile C++ code.
 //     PKG_CONFIG
 //             Path to pkg-config tool.
+//     AR
+//             The command to use to manipulate library archives when
+//             building with the gccgo compiler.
+//             The default is 'ar'.
 //
 // Architecture-specific environment variables:
 //

diff --git a/src/cmd/go/internal/help/helpdoc.go b/src/cmd/go/internal/help/helpdoc.go
index e2c4e61615bcc7c63539101ba68ec2d2ee44df52..c8ea66a3273d28bf67eefec1de029fa06756be3c 100644 (file)
--- a/src/cmd/go/internal/help/helpdoc.go
+++ b/src/cmd/go/internal/help/helpdoc.go
@@ -546,6 +546,10 @@ Environment variables for use with cgo:
                The command to use to compile C++ code.
        PKG_CONFIG
                Path to pkg-config tool.
+       AR
+               The command to use to manipulate library archives when
+               building with the gccgo compiler.
+               The default is 'ar'.
 
 Architecture-specific environment variables:
 

diff --git a/src/cmd/go/internal/work/gccgo.go b/src/cmd/go/internal/work/gccgo.go
index 784a4ae1b3fa553c4a89898f89f8153a3f13456c..69a25bea62ff449894c996bd985bdc0735f094b6 100644 (file)
--- a/src/cmd/go/internal/work/gccgo.go
+++ b/src/cmd/go/internal/work/gccgo.go
@@ -43,6 +43,14 @@ func (gccgoToolchain) linker() string {
        return GccgoBin
 }
 
+func (gccgoToolchain) ar() string {
+       ar := os.Getenv("AR")
+       if ar == "" {
+               ar = "ar"
+       }
+       return ar
+}
+
 func checkGccgoBin() {
        if gccgoErr == nil {
                return
@@ -183,7 +191,7 @@ func gccgoArchive(basedir, imp string) string {
        return filepath.Join(filepath.Dir(afile), "lib"+filepath.Base(afile))
 }
 
-func (gccgoToolchain) pack(b *Builder, a *Action, afile string, ofiles []string) error {
+func (tools gccgoToolchain) pack(b *Builder, a *Action, afile string, ofiles []string) error {
        p := a.Package
        objdir := a.Objdir
        var absOfiles []string
@@ -198,7 +206,7 @@ func (gccgoToolchain) pack(b *Builder, a *Action, afile string, ofiles []string)
                arArgs = []string{"-X64"}
        }
 
-       return b.run(a, p.Dir, p.ImportPath, nil, "ar", arArgs, "rc", mkAbs(objdir, afile), absOfiles)
+       return b.run(a, p.Dir, p.ImportPath, nil, tools.ar(), arArgs, "rc", mkAbs(objdir, afile), absOfiles)
 }
 
 func (tools gccgoToolchain) link(b *Builder, root *Action, out, importcfg string, allactions []*Action, buildmode, desc string) error {
@@ -257,11 +265,11 @@ func (tools gccgoToolchain) link(b *Builder, root *Action, out, importcfg string
                                return "", nil
                        }
                }
-               err := b.run(root, root.Objdir, desc, nil, "ar", "x", newArchive, "_cgo_flags")
+               err := b.run(root, root.Objdir, desc, nil, tools.ar(), "x", newArchive, "_cgo_flags")
                if err != nil {
                        return "", err
                }
-               err = b.run(root, ".", desc, nil, "ar", "d", newArchive, "_cgo_flags")
+               err = b.run(root, ".", desc, nil, tools.ar(), "d", newArchive, "_cgo_flags")
                if err != nil {
                        return "", err
                }
@@ -473,7 +481,7 @@ func (tools gccgoToolchain) link(b *Builder, root *Action, out, importcfg string
 
        switch buildmode {
        case "c-archive":
-               if err := b.run(root, ".", desc, nil, "ar", "rc", realOut, out); err != nil {
+               if err := b.run(root, ".", desc, nil, tools.ar(), "rc", realOut, out); err != nil {
                        return err
                }
        }