cmd/link: pass darwin/amd64-specific flags only on AMD64

The linker assumed macOS is AMD64 (and 386 in the past). It
passes darwin/amd64-specific flags to the external linker when
building for macOS. They don't work for ARM64-based macOS. So
only pass them on AMD64.

Disable DWARF combining for macOS ARM64 for now. The generated
binary doesn't run. (TODO: fix.)

For macOS ARM64 port. External linking now works.

Change-Id: Iab53bc48f4fadd9b91de8898b4b450ea442667a2
Reviewed-on: https://go-review.googlesource.com/c/go/+/253019
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
This commit is contained in:
Cherry Zhang 2020-09-02 21:04:12 -04:00
parent e61d17d3b9
commit 612b119447

View File

@ -1240,7 +1240,8 @@ func (ctxt *Link) hostlink() {
switch ctxt.HeadType {
case objabi.Hdarwin:
if machoPlatform == PLATFORM_MACOS {
if machoPlatform == PLATFORM_MACOS && ctxt.IsAMD64() {
// Leave room for DWARF combining.
// -headerpad is incompatible with -fembed-bitcode.
argv = append(argv, "-Wl,-headerpad,1144")
}
@ -1280,7 +1281,7 @@ func (ctxt *Link) hostlink() {
switch ctxt.BuildMode {
case BuildModeExe:
if ctxt.HeadType == objabi.Hdarwin {
if machoPlatform == PLATFORM_MACOS {
if machoPlatform == PLATFORM_MACOS && ctxt.IsAMD64() {
argv = append(argv, "-Wl,-no_pie")
argv = append(argv, "-Wl,-pagezero_size,4000000")
}
@ -1517,7 +1518,7 @@ func (ctxt *Link) hostlink() {
// does not work, the resulting programs will not run. See
// issue #17847. To avoid this problem pass -no-pie to the
// toolchain if it is supported.
if ctxt.BuildMode == BuildModeExe && !ctxt.linkShared {
if ctxt.BuildMode == BuildModeExe && !ctxt.linkShared && !(ctxt.IsDarwin() && ctxt.IsARM64()) {
// GCC uses -no-pie, clang uses -nopie.
for _, nopie := range []string{"-no-pie", "-nopie"} {
if linkerFlagSupported(argv[0], altLinker, nopie) {
@ -1607,7 +1608,7 @@ func (ctxt *Link) hostlink() {
Exitf("%s: parsing Mach-O header failed: %v", os.Args[0], err)
}
// Only macOS supports unmapped segments such as our __DWARF segment.
if machoPlatform == PLATFORM_MACOS {
if machoPlatform == PLATFORM_MACOS && ctxt.IsAMD64() {
if err := machoCombineDwarf(ctxt, exef, exem, dsym, combinedOutput); err != nil {
Exitf("%s: combining dwarf failed: %v", os.Args[0], err)
}