cmd/dist, cmd/link, cmd/go: make c-shared work on windows

Thanks to Christopher Nelson for spearheading the effort.

Fixes #11058

Change-Id: Icafabac8dc697626ff1bd943cc577b0b1cc6b349
Reviewed-on: https://go-review.googlesource.com/69091
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

diff --git a/src/cmd/dist/test.go b/src/cmd/dist/test.go
index 41fc84e3ede781962d3b297458110944ff2fc3e4..3bbeb76e4da1b02423c3fb0c0b0c5452186e066a 100644 (file)
--- a/src/cmd/dist/test.go
+++ b/src/cmd/dist/test.go
@@ -817,7 +817,8 @@ func (t *tester) supportedBuildmode(mode string) bool {
                switch pair {
                case "linux-386", "linux-amd64", "linux-arm", "linux-arm64", "linux-ppc64le",
                        "darwin-amd64", "darwin-386",
-                       "android-arm", "android-arm64", "android-386":
+                       "android-arm", "android-arm64", "android-386",
+                       "windows-amd64", "windows-386":
                        return true
                }
                return false

diff --git a/src/cmd/go/internal/work/build.go b/src/cmd/go/internal/work/build.go
index 92e2a3750dad1a9bdda57a280f65a125f3036a02..13bbabf65bdfa22af4d2e076f169331e12da947d 100644 (file)
--- a/src/cmd/go/internal/work/build.go
+++ b/src/cmd/go/internal/work/build.go
@@ -301,6 +301,9 @@ func BuildModeInit() {
                                "android/amd64", "android/arm", "android/arm64", "android/386":
                                codegenArg = "-shared"
                        case "darwin/amd64", "darwin/386":
+                       case "windows/amd64", "windows/386":
+                               // Do not add usual .exe suffix to the .dll file.
+                               cfg.ExeSuffix = ""
                        default:
                                base.Fatalf("-buildmode=c-shared not supported on %s\n", platform)
                        }
@@ -997,12 +1000,14 @@ func (b *Builder) action1(mode BuildMode, depMode BuildMode, p *load.Package, lo
                        name := "a.out"
                        if p.Internal.ExeName != "" {
                                name = p.Internal.ExeName
-                       } else if cfg.Goos == "darwin" && cfg.BuildBuildmode == "c-shared" && p.Internal.Target != "" {
+                       } else if (cfg.Goos == "darwin" || cfg.Goos == "windows") && cfg.BuildBuildmode == "c-shared" && p.Internal.Target != "" {
                                // On OS X, the linker output name gets recorded in the
                                // shared library's LC_ID_DYLIB load command.
                                // The code invoking the linker knows to pass only the final
                                // path element. Arrange that the path element matches what
                                // we'll install it as; otherwise the library is only loadable as "a.out".
+                               // On Windows, DLL file name is recorded in PE file
+                               // export section, so do like on OS X.
                                _, name = filepath.Split(p.Internal.Target)
                        }
                        a.Target = a.Objdir + filepath.Join("exe", name) + cfg.ExeSuffix
@@ -2641,8 +2646,10 @@ func (gcToolchain) ld(b *Builder, root *Action, out, importcfg string, allaction
        // (and making the resulting shared library useless),
        // run the link in the output directory so that -o can name
        // just the final path element.
+       // On Windows, DLL file name is recorded in PE file
+       // export section, so do like on OS X.
        dir := "."
-       if cfg.Goos == "darwin" && cfg.BuildBuildmode == "c-shared" {
+       if (cfg.Goos == "darwin" || cfg.Goos == "windows") && cfg.BuildBuildmode == "c-shared" {
                dir, out = filepath.Split(out)
        }
 

diff --git a/src/cmd/internal/obj/x86/asm6.go b/src/cmd/internal/obj/x86/asm6.go
index 7482b28c7407444623da7263c09179bb9636717f..53bef1cf7831483be06c22486e0f059d702856e6 100644 (file)
--- a/src/cmd/internal/obj/x86/asm6.go
+++ b/src/cmd/internal/obj/x86/asm6.go
@@ -2290,7 +2290,7 @@ func prefixof(ctxt *obj.Link, p *obj.Prog, a *obj.Addr) int {
                return 0x26
 
        case REG_TLS:
-               if ctxt.Flag_shared {
+               if ctxt.Flag_shared && ctxt.Headtype != objabi.Hwindows {
                        // When building for inclusion into a shared library, an instruction of the form
                        //     MOV 0(CX)(TLS*1), AX
                        // becomes

diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go
index 0621b22c75fc40d77012bfdfe421c4ea28ab2d9e..e4dcadb8a904646d14e3da3f5e1b7552c38b6a64 100644 (file)
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -592,7 +592,7 @@ func (ctxt *Link) loadlib() {
        }
 
        if ctxt.Arch == sys.Arch386 {
-               if (ctxt.BuildMode == BuildModeCArchive && Iself) || ctxt.BuildMode == BuildModeCShared || ctxt.BuildMode == BuildModePIE || ctxt.DynlinkingGo() {
+               if (ctxt.BuildMode == BuildModeCArchive && Iself) || (ctxt.BuildMode == BuildModeCShared && Headtype != objabi.Hwindows) || ctxt.BuildMode == BuildModePIE || ctxt.DynlinkingGo() {
                        got := ctxt.Syms.Lookup("_GLOBAL_OFFSET_TABLE_", 0)
                        got.Type = sym.SDYNIMPORT
                        got.Attr |= sym.AttrReachable
@@ -1126,9 +1126,12 @@ func (ctxt *Link) hostlink() {
                        if ctxt.UseRelro() {
                                argv = append(argv, "-Wl,-z,relro")
                        }
-                       // Pass -z nodelete to mark the shared library as
-                       // non-closeable: a dlclose will do nothing.
-                       argv = append(argv, "-shared", "-Wl,-z,nodelete")
+                       argv = append(argv, "-shared")
+                       if Headtype != objabi.Hwindows {
+                               // Pass -z nodelete to mark the shared library as
+                               // non-closeable: a dlclose will do nothing.
+                               argv = append(argv, "-Wl,-z,nodelete")
+                       }
                }
        case BuildModeShared:
                if ctxt.UseRelro() {