cmd/go: link SWIG objects directly rather than using a shared library

This change requires using SWIG version 3.0 or later.  Earlier
versions of SWIG do not generate the pragmas required to use
the external linker.

Fixes #7155.
Fixes #7156.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/97120046

diff --git a/doc/go1.3.html b/doc/go1.3.html
index 60effb294d24efb9e75768653db376a1a941c357..e13faa1b085c0d58d713c985384174e0064fca90 100644 (file)
--- a/doc/go1.3.html
+++ b/doc/go1.3.html
@@ -179,6 +179,15 @@ Finally, the go command now supports packages that import Objective-C
 files (suffixed <code>.m</code>) through cgo.
 </p>
 
+<h3 id="swig">SWIG 3.0 required for programs that use SWIG</h3>
+
+<p>
+For Go programs that use SWIG, SWIG version 3.0 is now required.  The
+<a href="/cmd/go"><code>cmd/go</code></a> command will now link the
+SWIG generated object files directly into the binary, rather than
+building and linking with a shared library.
+</p>
+
 <h3 id="gc_flag">Command-line flag parsing</h3>
 
 <p>

diff --git a/src/cmd/go/build.go b/src/cmd/go/build.go
index 78ff9ade389618a4e816ff3ce72f74b28f653e67..a6a21317e40212bb947faa0c2742d19ba43319b9 100644 (file)
--- a/src/cmd/go/build.go
+++ b/src/cmd/go/build.go
@@ -1048,21 +1048,6 @@ func (b *builder) install(a *action) (err error) {
                defer os.Remove(a1.target)
        }
 
-       if a.p.usesSwig() {
-               for _, f := range stringList(a.p.SwigFiles, a.p.SwigCXXFiles) {
-                       dir = a.p.swigDir(&buildContext)
-                       if err := b.mkdir(dir); err != nil {
-                               return err
-                       }
-                       soname := a.p.swigSoname(f)
-                       source := filepath.Join(a.objdir, soname)
-                       target := filepath.Join(dir, soname)
-                       if err = b.copyFile(a, target, source, perm); err != nil {
-                               return err
-                       }
-               }
-       }
-
        return b.moveOrCopyFile(a, a.target, a1.target, perm)
 }
 
@@ -1721,25 +1706,8 @@ func packInternal(b *builder, afile string, ofiles []string) error {
 
 func (gcToolchain) ld(b *builder, p *Package, out string, allactions []*action, mainpkg string, ofiles []string) error {
        importArgs := b.includeArgs("-L", allactions)
-       swigDirs := make(map[string]bool)
-       swigArg := []string{}
        cxx := false
        for _, a := range allactions {
-               if a.p != nil && a.p.usesSwig() {
-                       sd := a.p.swigDir(&buildContext)
-                       if len(swigArg) == 0 {
-                               swigArg = []string{"-r", sd}
-                       } else if !swigDirs[sd] {
-                               swigArg[1] += ":"
-                               swigArg[1] += sd
-                       }
-                       swigDirs[sd] = true
-                       if a.objdir != "" && !swigDirs[a.objdir] {
-                               swigArg[1] += ":"
-                               swigArg[1] += a.objdir
-                               swigDirs[a.objdir] = true
-                       }
-               }
                if a.p != nil && len(a.p.CXXFiles) > 0 {
                        cxx = true
                }
@@ -1792,7 +1760,7 @@ func (gcToolchain) ld(b *builder, p *Package, out string, allactions []*action,
                        }
                }
        }
-       return b.run(".", p.ImportPath, nil, tool(archChar+"l"), "-o", out, importArgs, swigArg, ldflags, mainpkg)
+       return b.run(".", p.ImportPath, nil, tool(archChar+"l"), "-o", out, importArgs, ldflags, mainpkg)
 }
 
 func (gcToolchain) cc(b *builder, p *Package, objdir, ofile, cfile string) error {
@@ -1865,7 +1833,6 @@ func (tools gccgoToolchain) ld(b *builder, p *Package, out string, allactions []
        // and all LDFLAGS from cgo dependencies.
        apackagesSeen := make(map[*Package]bool)
        afiles := []string{}
-       sfiles := []string{}
        ldflags := b.gccArchArgs()
        cgoldflags := []string{}
        usesCgo := false
@@ -1898,14 +1865,6 @@ func (tools gccgoToolchain) ld(b *builder, p *Package, out string, allactions []
                                usesCgo = true
                        }
                        if a.p.usesSwig() {
-                               sd := a.p.swigDir(&buildContext)
-                               if a.objdir != "" {
-                                       sd = a.objdir
-                               }
-                               for _, f := range stringList(a.p.SwigFiles, a.p.SwigCXXFiles) {
-                                       soname := a.p.swigSoname(f)
-                                       sfiles = append(sfiles, filepath.Join(sd, soname))
-                               }
                                usesCgo = true
                        }
                        if len(a.p.CXXFiles) > 0 {
@@ -1917,7 +1876,6 @@ func (tools gccgoToolchain) ld(b *builder, p *Package, out string, allactions []
                }
        }
        ldflags = append(ldflags, afiles...)
-       ldflags = append(ldflags, sfiles...)
        ldflags = append(ldflags, cgoldflags...)
        ldflags = append(ldflags, p.CgoLDFLAGS...)
        if usesCgo && goos == "linux" {
@@ -2364,13 +2322,12 @@ func (b *builder) swig(p *Package, obj string, gccfiles, gxxfiles, mfiles []stri
        cflags := stringList(cgoCPPFLAGS, cgoCFLAGS)
        cxxflags := stringList(cgoCPPFLAGS, cgoCXXFLAGS)
 
-       var extraObj []string
        for _, file := range gccfiles {
                ofile := obj + cgoRe.ReplaceAllString(file[:len(file)-1], "_") + "o"
                if err := b.gcc(p, ofile, cflags, file); err != nil {
                        return nil, nil, err
                }
-               extraObj = append(extraObj, ofile)
+               outObj = append(outObj, ofile)
        }
 
        for _, file := range gxxfiles {
@@ -2379,7 +2336,7 @@ func (b *builder) swig(p *Package, obj string, gccfiles, gxxfiles, mfiles []stri
                if err := b.gxx(p, ofile, cxxflags, file); err != nil {
                        return nil, nil, err
                }
-               extraObj = append(extraObj, ofile)
+               outObj = append(outObj, ofile)
        }
 
        for _, file := range mfiles {
@@ -2388,7 +2345,7 @@ func (b *builder) swig(p *Package, obj string, gccfiles, gxxfiles, mfiles []stri
                if err := b.gcc(p, ofile, cflags, file); err != nil {
                        return nil, nil, err
                }
-               extraObj = append(extraObj, ofile)
+               outObj = append(outObj, ofile)
        }
 
        intgosize, err := b.swigIntSize(obj)
@@ -2397,7 +2354,7 @@ func (b *builder) swig(p *Package, obj string, gccfiles, gxxfiles, mfiles []stri
        }
 
        for _, f := range p.SwigFiles {
-               goFile, objFile, err := b.swigOne(p, f, obj, false, intgosize, extraObj)
+               goFile, objFile, gccObjFile, err := b.swigOne(p, f, obj, false, intgosize)
                if err != nil {
                        return nil, nil, err
                }
@@ -2407,9 +2364,12 @@ func (b *builder) swig(p *Package, obj string, gccfiles, gxxfiles, mfiles []stri
                if objFile != "" {
                        outObj = append(outObj, objFile)
                }
+               if gccObjFile != "" {
+                       outObj = append(outObj, gccObjFile)
+               }
        }
        for _, f := range p.SwigCXXFiles {
-               goFile, objFile, err := b.swigOne(p, f, obj, true, intgosize, extraObj)
+               goFile, objFile, gccObjFile, err := b.swigOne(p, f, obj, true, intgosize)
                if err != nil {
                        return nil, nil, err
                }
@@ -2419,6 +2379,9 @@ func (b *builder) swig(p *Package, obj string, gccfiles, gxxfiles, mfiles []stri
                if objFile != "" {
                        outObj = append(outObj, objFile)
                }
+               if gccObjFile != "" {
+                       outObj = append(outObj, gccObjFile)
+               }
        }
        return outGo, outObj, nil
 }
@@ -2450,13 +2413,13 @@ func (b *builder) swigIntSize(obj string) (intsize string, err error) {
 }
 
 // Run SWIG on one SWIG input file.
-func (b *builder) swigOne(p *Package, file, obj string, cxx bool, intgosize string, extraObj []string) (outGo, outObj string, err error) {
-       cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, cgoLDFLAGS := b.cflags(p, true)
+func (b *builder) swigOne(p *Package, file, obj string, cxx bool, intgosize string) (outGo, outObj, objGccObj string, err error) {
+       cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, _ := b.cflags(p, true)
        var cflags []string
        if cxx {
-               cflags = stringList(cgoCPPFLAGS, cgoCXXFLAGS, "-fPIC")
+               cflags = stringList(cgoCPPFLAGS, cgoCXXFLAGS)
        } else {
-               cflags = stringList(cgoCPPFLAGS, cgoCFLAGS, "-fPIC")
+               cflags = stringList(cgoCPPFLAGS, cgoCFLAGS)
        }
 
        n := 5 // length of ".swig"
@@ -2471,7 +2434,6 @@ func (b *builder) swigOne(p *Package, file, obj string, cxx bool, intgosize stri
        if cxx {
                gccExt = "cxx"
        }
-       soname := p.swigSoname(file)
 
        _, gccgo := buildToolchain.(gccgoToolchain)
 
@@ -2480,12 +2442,14 @@ func (b *builder) swigOne(p *Package, file, obj string, cxx bool, intgosize stri
                "-go",
                "-intgosize", intgosize,
                "-module", base,
-               "-soname", soname,
                "-o", obj + gccBase + gccExt,
                "-outdir", obj,
        }
        if gccgo {
                args = append(args, "-gccgo")
+               if pkgpath := gccgoPkgpath(p); pkgpath != "" {
+                       args = append(args, "-go-pkgpath", pkgpath)
+               }
        }
        if cxx {
                args = append(args, "-c++")
@@ -2494,12 +2458,12 @@ func (b *builder) swigOne(p *Package, file, obj string, cxx bool, intgosize stri
        if out, err := b.runOut(p.Dir, p.ImportPath, nil, "swig", args, file); err != nil {
                if len(out) > 0 {
                        if bytes.Contains(out, []byte("Unrecognized option -intgosize")) {
-                               return "", "", errors.New("must have SWIG version >= 2.0.9\n")
+                               return "", "", "", errors.New("must have SWIG version >= 3.0\n")
                        }
                        b.showOutput(p.Dir, p.ImportPath, b.processOutput(out))
-                       return "", "", errPrintedOutput
+                       return "", "", "", errPrintedOutput
                }
-               return "", "", err
+               return "", "", "", err
        }
 
        var cObj string
@@ -2507,7 +2471,7 @@ func (b *builder) swigOne(p *Package, file, obj string, cxx bool, intgosize stri
                // cc
                cObj = obj + cBase + archChar
                if err := buildToolchain.cc(b, p, obj, cObj, obj+cBase+"c"); err != nil {
-                       return "", "", err
+                       return "", "", "", err
                }
        }
 
@@ -2515,32 +2479,15 @@ func (b *builder) swigOne(p *Package, file, obj string, cxx bool, intgosize stri
        gccObj := obj + gccBase + "o"
        if !cxx {
                if err := b.gcc(p, gccObj, cflags, obj+gccBase+gccExt); err != nil {
-                       return "", "", err
+                       return "", "", "", err
                }
        } else {
                if err := b.gxx(p, gccObj, cflags, obj+gccBase+gccExt); err != nil {
-                       return "", "", err
+                       return "", "", "", err
                }
        }
 
-       // create shared library
-       osldflags := map[string][]string{
-               "darwin":  {"-dynamiclib", "-Wl,-undefined,dynamic_lookup"},
-               "freebsd": {"-shared", "-lpthread", "-lm"},
-               "linux":   {"-shared", "-lpthread", "-lm"},
-               "windows": {"-shared", "-lm", "-mthreads"},
-       }
-       var cxxlib []string
-       if cxx {
-               cxxlib = []string{"-lstdc++"}
-       }
-       ldflags := stringList(osldflags[goos], cflags, cgoLDFLAGS, cxxlib)
-       target := filepath.Join(obj, soname)
-       if err := b.run(p.Dir, p.ImportPath, nil, b.gccCmd(p.Dir), "-o", target, gccObj, extraObj, ldflags); err != nil {
-               return "", "", err
-       }
-
-       return obj + goFile, cObj, nil
+       return obj + goFile, cObj, gccObj, nil
 }
 
 // An actionQueue is a priority queue of actions.

diff --git a/src/cmd/go/clean.go b/src/cmd/go/clean.go
index 3028193bc7d5185708cf23cf3eea852c2ff778f6..16054a5b5bc33869a78ac1eaac2fe4a19c6a8587 100644 (file)
--- a/src/cmd/go/clean.go
+++ b/src/cmd/go/clean.go
@@ -216,20 +216,6 @@ func clean(p *Package) {
                }
        }
 
-       if cleanI && p.usesSwig() {
-               for _, f := range stringList(p.SwigFiles, p.SwigCXXFiles) {
-                       dir := p.swigDir(&buildContext)
-                       soname := p.swigSoname(f)
-                       target := filepath.Join(dir, soname)
-                       if buildN || buildX {
-                               b.showcmd("", "rm -f %s", target)
-                       }
-                       if !buildN {
-                               removeFile(target)
-                       }
-               }
-       }
-
        if cleanR {
                for _, p1 := range p.imports {
                        clean(p1)

diff --git a/src/cmd/go/doc.go b/src/cmd/go/doc.go
index 7fe0008a076138a9949c17d4883f60d1c5e03b11..05dc9c2bdfdc27e1dc8e5ee277db4edcc01a9def 100644 (file)
--- a/src/cmd/go/doc.go
+++ b/src/cmd/go/doc.go
@@ -144,7 +144,6 @@ source directories corresponding to the import paths:
        DIR(.exe)        from go build
        DIR.test(.exe)   from go test -c
        MAINFILE(.exe)   from go build MAINFILE.go
-       *.so             from SWIG
 
 In the list, DIR represents the final path element of the
 directory, and MAINFILE is the base name of any Go source

diff --git a/src/cmd/go/pkg.go b/src/cmd/go/pkg.go
index 59c5d357e37f3e868bb0683b74b3db17edd6bfb5..7c78f8e6679bca0373a759959d18916f482f9223 100644 (file)
--- a/src/cmd/go/pkg.go
+++ b/src/cmd/go/pkg.go
@@ -560,24 +560,6 @@ func (p *Package) usesCgo() bool {
        return len(p.CgoFiles) > 0
 }
 
-// swigSoname returns the name of the shared library we create for a
-// SWIG input file.
-func (p *Package) swigSoname(file string) string {
-       return strings.Replace(p.ImportPath, "/", "-", -1) + "-" + strings.Replace(file, ".", "-", -1) + ".so"
-}
-
-// swigDir returns the name of the shared SWIG directory for a
-// package.
-func (p *Package) swigDir(ctxt *build.Context) string {
-       dir := p.build.PkgRoot
-       if ctxt.Compiler == "gccgo" {
-               dir = filepath.Join(dir, "gccgo_"+ctxt.GOOS+"_"+ctxt.GOARCH)
-       } else {
-               dir = filepath.Join(dir, ctxt.GOOS+"_"+ctxt.GOARCH)
-       }
-       return filepath.Join(dir, "swig")
-}
-
 // packageList returns the list of packages in the dag rooted at roots
 // as visited in a depth-first post-order traversal.
 func packageList(roots []*Package) []*Package {