internal/buildcfg: move build configuration out of cmd/internal/objabi

The go/build package needs access to this configuration,
so move it into a new package available to the standard library.

Change-Id: I868a94148b52350c76116451f4ad9191246adcff
Reviewed-on: https://go-review.googlesource.com/c/go/+/310731
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>

19 files changed, 106 insertions, 90 deletions

diff --git a/src/cmd/link/internal/ld/ar.go b/src/cmd/link/internal/ld/ar.go
index e4fd591676..22f53a4df2 100644
--- a/src/cmd/link/internal/ld/ar.go
+++ b/src/cmd/link/internal/ld/ar.go
@@ -32,10 +32,10 @@ package ld
 
 import (
 	"cmd/internal/bio"
-	"cmd/internal/objabi"
 	"cmd/link/internal/sym"
 	"encoding/binary"
 	"fmt"
+	"internal/buildcfg"
 	"io"
 	"os"
 )
@@ -170,7 +170,7 @@ func readArmap(filename string, f *bio.Reader, arhdr ArHdr) archiveMap {
 
 		// For Mach-O and PE/386 files we strip a leading
 		// underscore from the symbol name.
-		if objabi.GOOS == "darwin" || objabi.GOOS == "ios" || (objabi.GOOS == "windows" && objabi.GOARCH == "386") {
+		if buildcfg.GOOS == "darwin" || buildcfg.GOOS == "ios" || (buildcfg.GOOS == "windows" && buildcfg.GOARCH == "386") {
 			if name[0] == '_' && len(name) > 1 {
 				name = name[1:]
 			}
diff --git a/src/cmd/link/internal/ld/config.go b/src/cmd/link/internal/ld/config.go
index 9228962fb3..75fddc6a38 100644
--- a/src/cmd/link/internal/ld/config.go
+++ b/src/cmd/link/internal/ld/config.go
@@ -5,9 +5,9 @@
 package ld
 
 import (
-	"cmd/internal/objabi"
 	"cmd/internal/sys"
 	"fmt"
+	"internal/buildcfg"
 )
 
 // A BuildMode indicates the sort of object we are building.
@@ -28,23 +28,23 @@ const (
 
 func (mode *BuildMode) Set(s string) error {
 	badmode := func() error {
-		return fmt.Errorf("buildmode %s not supported on %s/%s", s, objabi.GOOS, objabi.GOARCH)
+		return fmt.Errorf("buildmode %s not supported on %s/%s", s, buildcfg.GOOS, buildcfg.GOARCH)
 	}
 	switch s {
 	default:
 		return fmt.Errorf("invalid buildmode: %q", s)
 	case "exe":
-		switch objabi.GOOS + "/" + objabi.GOARCH {
+		switch buildcfg.GOOS + "/" + buildcfg.GOARCH {
 		case "darwin/arm64", "windows/arm", "windows/arm64": // On these platforms, everything is PIE
 			*mode = BuildModePIE
 		default:
 			*mode = BuildModeExe
 		}
 	case "pie":
-		switch objabi.GOOS {
+		switch buildcfg.GOOS {
 		case "aix", "android", "linux", "windows", "darwin", "ios":
 		case "freebsd":
-			switch objabi.GOARCH {
+			switch buildcfg.GOARCH {
 			case "amd64":
 			default:
 				return badmode()
@@ -54,16 +54,16 @@ func (mode *BuildMode) Set(s string) error {
 		}
 		*mode = BuildModePIE
 	case "c-archive":
-		switch objabi.GOOS {
+		switch buildcfg.GOOS {
 		case "aix", "darwin", "ios", "linux":
 		case "freebsd":
-			switch objabi.GOARCH {
+			switch buildcfg.GOARCH {
 			case "amd64":
 			default:
 				return badmode()
 			}
 		case "windows":
-			switch objabi.GOARCH {
+			switch buildcfg.GOARCH {
 			case "amd64", "386", "arm", "arm64":
 			default:
 				return badmode()
@@ -73,16 +73,16 @@ func (mode *BuildMode) Set(s string) error {
 		}
 		*mode = BuildModeCArchive
 	case "c-shared":
-		switch objabi.GOARCH {
+		switch buildcfg.GOARCH {
 		case "386", "amd64", "arm", "arm64", "ppc64le", "s390x":
 		default:
 			return badmode()
 		}
 		*mode = BuildModeCShared
 	case "shared":
-		switch objabi.GOOS {
+		switch buildcfg.GOOS {
 		case "linux":
-			switch objabi.GOARCH {
+			switch buildcfg.GOARCH {
 			case "386", "amd64", "arm", "arm64", "ppc64le", "s390x":
 			default:
 				return badmode()
@@ -92,21 +92,21 @@ func (mode *BuildMode) Set(s string) error {
 		}
 		*mode = BuildModeShared
 	case "plugin":
-		switch objabi.GOOS {
+		switch buildcfg.GOOS {
 		case "linux":
-			switch objabi.GOARCH {
+			switch buildcfg.GOARCH {
 			case "386", "amd64", "arm", "arm64", "s390x", "ppc64le":
 			default:
 				return badmode()
 			}
 		case "darwin":
-			switch objabi.GOARCH {
+			switch buildcfg.GOARCH {
 			case "amd64", "arm64":
 			default:
 				return badmode()
 			}
 		case "freebsd":
-			switch objabi.GOARCH {
+			switch buildcfg.GOARCH {
 			case "amd64":
 			default:
 				return badmode()
@@ -185,8 +185,8 @@ func mustLinkExternal(ctxt *Link) (res bool, reason string) {
 		}()
 	}
 
-	if sys.MustLinkExternal(objabi.GOOS, objabi.GOARCH) {
-		return true, fmt.Sprintf("%s/%s requires external linking", objabi.GOOS, objabi.GOARCH)
+	if sys.MustLinkExternal(buildcfg.GOOS, buildcfg.GOARCH) {
+		return true, fmt.Sprintf("%s/%s requires external linking", buildcfg.GOOS, buildcfg.GOARCH)
 	}
 
 	if *flagMsan {
@@ -197,20 +197,20 @@ func mustLinkExternal(ctxt *Link) (res bool, reason string) {
 	// https://golang.org/issue/14449
 	// https://golang.org/issue/21961
 	if iscgo && ctxt.Arch.InFamily(sys.MIPS64, sys.MIPS, sys.PPC64, sys.RISCV64) {
-		return true, objabi.GOARCH + " does not support internal cgo"
+		return true, buildcfg.GOARCH + " does not support internal cgo"
 	}
-	if iscgo && (objabi.GOOS == "android" || objabi.GOOS == "dragonfly") {
+	if iscgo && (buildcfg.GOOS == "android" || buildcfg.GOOS == "dragonfly") {
 		// It seems that on Dragonfly thread local storage is
 		// set up by the dynamic linker, so internal cgo linking
 		// doesn't work. Test case is "go test runtime/cgo".
-		return true, objabi.GOOS + " does not support internal cgo"
+		return true, buildcfg.GOOS + " does not support internal cgo"
 	}
 
 	// When the race flag is set, the LLVM tsan relocatable file is linked
 	// into the final binary, which means external linking is required because
 	// internal linking does not support it.
 	if *flagRace && ctxt.Arch.InFamily(sys.PPC64) {
-		return true, "race on " + objabi.GOARCH
+		return true, "race on " + buildcfg.GOARCH
 	}
 
 	// Some build modes require work the internal linker cannot do (yet).
@@ -220,7 +220,7 @@ func mustLinkExternal(ctxt *Link) (res bool, reason string) {
 	case BuildModeCShared:
 		return true, "buildmode=c-shared"
 	case BuildModePIE:
-		switch objabi.GOOS + "/" + objabi.GOARCH {
+		switch buildcfg.GOOS + "/" + buildcfg.GOARCH {
 		case "linux/amd64", "linux/arm64", "android/arm64":
 		case "windows/386", "windows/amd64", "windows/arm", "windows/arm64":
 		case "darwin/amd64", "darwin/arm64":
@@ -254,7 +254,7 @@ func determineLinkMode(ctxt *Link) {
 		// default value of -linkmode. If it is not set when the
 		// linker is called we take the value it was set to when
 		// cmd/link was compiled. (See make.bash.)
-		switch objabi.Getgoextlinkenabled() {
+		switch buildcfg.Getgoextlinkenabled() {
 		case "0":
 			ctxt.LinkMode = LinkInternal
 			via = "via GO_EXTLINK_ENABLED "
@@ -277,8 +277,8 @@ func determineLinkMode(ctxt *Link) {
 		}
 	case LinkExternal:
 		switch {
-		case objabi.GOARCH == "ppc64" && objabi.GOOS != "aix":
-			Exitf("external linking not supported for %s/ppc64", objabi.GOOS)
+		case buildcfg.GOARCH == "ppc64" && buildcfg.GOOS != "aix":
+			Exitf("external linking not supported for %s/ppc64", buildcfg.GOOS)
 		}
 	}
 }
diff --git a/src/cmd/link/internal/ld/data_test.go b/src/cmd/link/internal/ld/data_test.go
index 7c46307bd8..f91493bc41 100644
--- a/src/cmd/link/internal/ld/data_test.go
+++ b/src/cmd/link/internal/ld/data_test.go
@@ -8,6 +8,7 @@ import (
 	"cmd/internal/objabi"
 	"cmd/internal/sys"
 	"cmd/link/internal/loader"
+	"internal/buildcfg"
 	"testing"
 )
 
@@ -63,14 +64,14 @@ func TestAddGotSym(t *testing.T) {
 	}
 
 	// Save the architecture as we're going to set it on each test run.
-	origArch := objabi.GOARCH
+	origArch := buildcfg.GOARCH
 	defer func() {
-		objabi.GOARCH = origArch
+		buildcfg.GOARCH = origArch
 	}()
 
 	for i, test := range tests {
 		iself := len(test.rel) != 0
-		objabi.GOARCH = test.arch.Name
+		buildcfg.GOARCH = test.arch.Name
 		ctxt := setUpContext(test.arch, iself, test.ht, test.bm, test.lm)
 		foo := ctxt.loader.CreateSymForUpdate("foo", 0)
 		ctxt.loader.CreateExtSym("bar", 0)
diff --git a/src/cmd/link/internal/ld/deadcode.go b/src/cmd/link/internal/ld/deadcode.go
index 741a72cad8..1ed5598c99 100644
--- a/src/cmd/link/internal/ld/deadcode.go
+++ b/src/cmd/link/internal/ld/deadcode.go
@@ -11,6 +11,7 @@ import (
 	"cmd/link/internal/loader"
 	"cmd/link/internal/sym"
 	"fmt"
+	"internal/buildcfg"
 	"unicode"
 )
 
@@ -32,7 +33,7 @@ type deadcodePass struct {
 func (d *deadcodePass) init() {
 	d.ldr.InitReachable()
 	d.ifaceMethod = make(map[methodsig]bool)
-	if objabi.Experiment.FieldTrack {
+	if buildcfg.Experiment.FieldTrack {
 		d.ldr.Reachparent = make([]loader.Sym, d.ldr.NSym())
 	}
 	d.dynlink = d.ctxt.DynlinkingGo()
@@ -258,7 +259,7 @@ func (d *deadcodePass) mark(symIdx, parent loader.Sym) {
 	if symIdx != 0 && !d.ldr.AttrReachable(symIdx) {
 		d.wq.push(symIdx)
 		d.ldr.SetAttrReachable(symIdx, true)
-		if objabi.Experiment.FieldTrack && d.ldr.Reachparent[symIdx] == 0 {
+		if buildcfg.Experiment.FieldTrack && d.ldr.Reachparent[symIdx] == 0 {
 			d.ldr.Reachparent[symIdx] = parent
 		}
 		if *flagDumpDep {
diff --git a/src/cmd/link/internal/ld/dwarf.go b/src/cmd/link/internal/ld/dwarf.go
index 2f19c3eaa2..c53d2408cb 100644
--- a/src/cmd/link/internal/ld/dwarf.go
+++ b/src/cmd/link/internal/ld/dwarf.go
@@ -22,6 +22,7 @@ import (
 	"cmd/link/internal/loader"
 	"cmd/link/internal/sym"
 	"fmt"
+	"internal/buildcfg"
 	"log"
 	"path"
 	"runtime"
@@ -1843,7 +1844,7 @@ func dwarfGenerateDebugInfo(ctxt *Link) {
 			if producerExtra := d.ldr.Lookup(dwarf.CUInfoPrefix+"producer."+unit.Lib.Pkg, 0); producerExtra != 0 {
 				peData = d.ldr.Data(producerExtra)
 			}
-			producer := "Go cmd/compile " + objabi.Version
+			producer := "Go cmd/compile " + buildcfg.Version
 			if len(peData) > 0 {
 				// We put a semicolon before the flags to clearly
 				// separate them from the version, which can be long
diff --git a/src/cmd/link/internal/ld/elf.go b/src/cmd/link/internal/ld/elf.go
index 3ba9f329ee..87d88dd957 100644
--- a/src/cmd/link/internal/ld/elf.go
+++ b/src/cmd/link/internal/ld/elf.go
@@ -14,6 +14,7 @@ import (
 	"encoding/binary"
 	"encoding/hex"
 	"fmt"
+	"internal/buildcfg"
 	"path/filepath"
 	"sort"
 	"strings"
@@ -584,7 +585,7 @@ func elfWriteMipsAbiFlags(ctxt *Link) int {
 	ctxt.Out.Write8(1)  // gprSize
 	ctxt.Out.Write8(1)  // cpr1Size
 	ctxt.Out.Write8(0)  // cpr2Size
-	if objabi.GOMIPS == "softfloat" {
+	if buildcfg.GOMIPS == "softfloat" {
 		ctxt.Out.Write8(MIPS_FPABI_SOFT) // fpAbi
 	} else {
 		// Go cannot make sure non odd-number-fpr is used (ie, in load a double from memory).
@@ -1557,7 +1558,7 @@ func (ctxt *Link) doelf() {
 		gnuattributes.AddUint8(1)                 // 1:file, 2: section, 3: symbol, 1 here
 		gnuattributes.AddUint32(ctxt.Arch, 7)     // tag length, including tag, 7 here
 		gnuattributes.AddUint8(4)                 // 4 for FP, 8 for MSA
-		if objabi.GOMIPS == "softfloat" {
+		if buildcfg.GOMIPS == "softfloat" {
 			gnuattributes.AddUint8(MIPS_FPABI_SOFT)
 		} else {
 			// Note: MIPS_FPABI_ANY is bad naming: in fact it is MIPS I style FPR usage.
@@ -1743,14 +1744,14 @@ func asmbElf(ctxt *Link) {
 		sh.Flags = uint64(elf.SHF_ALLOC)
 		sh.Addralign = 1
 
-		if interpreter == "" && objabi.GO_LDSO != "" {
-			interpreter = objabi.GO_LDSO
+		if interpreter == "" && buildcfg.GO_LDSO != "" {
+			interpreter = buildcfg.GO_LDSO
 		}
 
 		if interpreter == "" {
 			switch ctxt.HeadType {
 			case objabi.Hlinux:
-				if objabi.GOOS == "android" {
+				if buildcfg.GOOS == "android" {
 					interpreter = thearch.Androiddynld
 					if interpreter == "" {
 						Exitf("ELF interpreter not set")
diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go
index b709569103..b814a277e6 100644
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -49,6 +49,7 @@ import (
 	"encoding/base64"
 	"encoding/binary"
 	"fmt"
+	"internal/buildcfg"
 	exec "internal/execabs"
 	"io"
 	"io/ioutil"
@@ -379,7 +380,7 @@ func libinit(ctxt *Link) {
 		suffix = "msan"
 	}
 
-	Lflag(ctxt, filepath.Join(objabi.GOROOT, "pkg", fmt.Sprintf("%s_%s%s%s", objabi.GOOS, objabi.GOARCH, suffixsep, suffix)))
+	Lflag(ctxt, filepath.Join(buildcfg.GOROOT, "pkg", fmt.Sprintf("%s_%s%s%s", buildcfg.GOOS, buildcfg.GOARCH, suffixsep, suffix)))
 
 	mayberemoveoutfile()
 
@@ -390,9 +391,9 @@ func libinit(ctxt *Link) {
 	if *flagEntrySymbol == "" {
 		switch ctxt.BuildMode {
 		case BuildModeCShared, BuildModeCArchive:
-			*flagEntrySymbol = fmt.Sprintf("_rt0_%s_%s_lib", objabi.GOARCH, objabi.GOOS)
+			*flagEntrySymbol = fmt.Sprintf("_rt0_%s_%s_lib", buildcfg.GOARCH, buildcfg.GOOS)
 		case BuildModeExe, BuildModePIE:
-			*flagEntrySymbol = fmt.Sprintf("_rt0_%s_%s", objabi.GOARCH, objabi.GOOS)
+			*flagEntrySymbol = fmt.Sprintf("_rt0_%s_%s", buildcfg.GOARCH, buildcfg.GOOS)
 		case BuildModeShared, BuildModePlugin:
 			// No *flagEntrySymbol for -buildmode=shared and plugin
 		default:
@@ -495,7 +496,7 @@ func (ctxt *Link) loadlib() {
 	default:
 		log.Fatalf("invalid -strictdups flag value %d", *FlagStrictDups)
 	}
-	if !objabi.Experiment.RegabiWrappers || ctxt.linkShared {
+	if !buildcfg.Experiment.RegabiWrappers || ctxt.linkShared {
 		// Use ABI aliases if ABI wrappers are not used.
 		// TODO: for now we still use ABI aliases in shared linkage, even if
 		// the wrapper is enabled.
@@ -543,7 +544,7 @@ func (ctxt *Link) loadlib() {
 	// We now have enough information to determine the link mode.
 	determineLinkMode(ctxt)
 
-	if ctxt.LinkMode == LinkExternal && !iscgo && !(objabi.GOOS == "darwin" && ctxt.BuildMode != BuildModePlugin && ctxt.Arch.Family == sys.AMD64) {
+	if ctxt.LinkMode == LinkExternal && !iscgo && !(buildcfg.GOOS == "darwin" && ctxt.BuildMode != BuildModePlugin && ctxt.Arch.Family == sys.AMD64) {
 		// This indicates a user requested -linkmode=external.
 		// The startup code uses an import of runtime/cgo to decide
 		// whether to initialize the TLS.  So give it one. This could
@@ -705,7 +706,7 @@ func (ctxt *Link) linksetup() {
 		}
 	}
 
-	if ctxt.LinkMode == LinkExternal && ctxt.Arch.Family == sys.PPC64 && objabi.GOOS != "aix" {
+	if ctxt.LinkMode == LinkExternal && ctxt.Arch.Family == sys.PPC64 && buildcfg.GOOS != "aix" {
 		toc := ctxt.loader.LookupOrCreateSym(".TOC.", 0)
 		sb := ctxt.loader.MakeSymbolUpdater(toc)
 		sb.SetType(sym.SDYNIMPORT)
@@ -714,7 +715,7 @@ func (ctxt *Link) linksetup() {
 	// The Android Q linker started to complain about underalignment of the our TLS
 	// section. We don't actually use the section on android, so don't
 	// generate it.
-	if objabi.GOOS != "android" {
+	if buildcfg.GOOS != "android" {
 		tlsg := ctxt.loader.LookupOrCreateSym("runtime.tlsg", 0)
 		sb := ctxt.loader.MakeSymbolUpdater(tlsg)
 
@@ -755,7 +756,7 @@ func (ctxt *Link) linksetup() {
 			sb := ctxt.loader.MakeSymbolUpdater(goarm)
 			sb.SetType(sym.SDATA)
 			sb.SetSize(0)
-			sb.AddUint8(uint8(objabi.GOARM))
+			sb.AddUint8(uint8(buildcfg.GOARM))
 		}
 
 		// Set runtime.disableMemoryProfiling bool if
@@ -1248,7 +1249,7 @@ func (ctxt *Link) hostlink() {
 			// -headerpad is incompatible with -fembed-bitcode.
 			argv = append(argv, "-Wl,-headerpad,1144")
 		}
-		if ctxt.DynlinkingGo() && objabi.GOOS != "ios" {
+		if ctxt.DynlinkingGo() && buildcfg.GOOS != "ios" {
 			// -flat_namespace is deprecated on iOS.
 			// It is useful for supporting plugins. We don't support plugins on iOS.
 			argv = append(argv, "-Wl,-flat_namespace")
@@ -1366,12 +1367,12 @@ func (ctxt *Link) hostlink() {
 		// from the beginning of the section (like sym.STYPE).
 		argv = append(argv, "-Wl,-znocopyreloc")
 
-		if objabi.GOOS == "android" {
+		if buildcfg.GOOS == "android" {
 			// Use lld to avoid errors from default linker (issue #38838)
 			altLinker = "lld"
 		}
 
-		if ctxt.Arch.InFamily(sys.ARM, sys.ARM64) && objabi.GOOS == "linux" {
+		if ctxt.Arch.InFamily(sys.ARM, sys.ARM64) && buildcfg.GOOS == "linux" {
 			// On ARM, the GNU linker will generate COPY relocations
 			// even with -znocopyreloc set.
 			// https://sourceware.org/bugzilla/show_bug.cgi?id=19962
@@ -1393,7 +1394,7 @@ func (ctxt *Link) hostlink() {
 			}
 		}
 	}
-	if ctxt.Arch.Family == sys.ARM64 && objabi.GOOS == "freebsd" {
+	if ctxt.Arch.Family == sys.ARM64 && buildcfg.GOOS == "freebsd" {
 		// Switch to ld.bfd on freebsd/arm64.
 		altLinker = "bfd"
 
@@ -1420,7 +1421,7 @@ func (ctxt *Link) hostlink() {
 	// only want to do this when producing a Windows output file
 	// on a Windows host.
 	outopt := *flagOutfile
-	if objabi.GOOS == "windows" && runtime.GOOS == "windows" && filepath.Ext(outopt) == "" {
+	if buildcfg.GOOS == "windows" && runtime.GOOS == "windows" && filepath.Ext(outopt) == "" {
 		outopt += "."
 	}
 	argv = append(argv, "-o")
@@ -1737,7 +1738,7 @@ func hostlinkArchArgs(arch *sys.Arch) []string {
 	case sys.I386:
 		return []string{"-m32"}
 	case sys.AMD64:
-		if objabi.GOOS == "darwin" {
+		if buildcfg.GOOS == "darwin" {
 			return []string{"-arch", "x86_64", "-m64"}
 		}
 		return []string{"-m64"}
@@ -1746,7 +1747,7 @@ func hostlinkArchArgs(arch *sys.Arch) []string {
 	case sys.ARM:
 		return []string{"-marm"}
 	case sys.ARM64:
-		if objabi.GOOS == "darwin" {
+		if buildcfg.GOOS == "darwin" {
 			return []string{"-arch", "arm64"}
 		}
 	case sys.MIPS64:
@@ -1754,7 +1755,7 @@ func hostlinkArchArgs(arch *sys.Arch) []string {
 	case sys.MIPS:
 		return []string{"-mabi=32"}
 	case sys.PPC64:
-		if objabi.GOOS == "aix" {
+		if buildcfg.GOOS == "aix" {
 			return []string{"-maix64"}
 		} else {
 			return []string{"-m64"}
@@ -1862,7 +1863,7 @@ func ldobj(ctxt *Link, f *bio.Reader, lib *sym.Library, length int64, pn string,
 	}
 
 	// First, check that the basic GOOS, GOARCH, and Version match.
-	t := fmt.Sprintf("%s %s %s ", objabi.GOOS, objabi.GOARCH, objabi.Version)
+	t := fmt.Sprintf("%s %s %s ", buildcfg.GOOS, buildcfg.GOARCH, buildcfg.Version)
 
 	line = strings.TrimRight(line, "\n")
 	if !strings.HasPrefix(line[10:]+" ", t) && !*flagF {
@@ -2084,7 +2085,7 @@ func ldshlibsyms(ctxt *Link, shlib string) {
 
 	// collect text symbol ABI versions.
 	symabi := make(map[string]int) // map (unmangled) symbol name to version
-	if objabi.Experiment.RegabiWrappers {
+	if buildcfg.Experiment.RegabiWrappers {
 		for _, elfsym := range syms {
 			if elf.ST_TYPE(elfsym.Info) != elf.STT_FUNC {
 				continue
@@ -2112,7 +2113,7 @@ func ldshlibsyms(ctxt *Link, shlib string) {
 		symname := elfsym.Name // (unmangled) symbol name
 		if elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC && strings.HasPrefix(elfsym.Name, "type.") {
 			ver = sym.SymVerABIInternal
-		} else if objabi.Experiment.RegabiWrappers && elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC {
+		} else if buildcfg.Experiment.RegabiWrappers && elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC {
 			if strings.HasSuffix(elfsym.Name, ".abiinternal") {
 				ver = sym.SymVerABIInternal
 				symname = strings.TrimSuffix(elfsym.Name, ".abiinternal")
@@ -2162,7 +2163,7 @@ func ldshlibsyms(ctxt *Link, shlib string) {
 		// mangle Go function names in the .so to include the
 		// ABI.
 		if elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC && ver == 0 {
-			if objabi.Experiment.RegabiWrappers {
+			if buildcfg.Experiment.RegabiWrappers {
 				if _, ok := symabi[symname]; ok {
 					continue // only use alias for functions w/o ABI wrappers
 				}
@@ -2234,7 +2235,7 @@ func (ctxt *Link) dostkcheck() {
 	// of non-splitting functions.
 	var ch chain
 	ch.limit = objabi.StackLimit - callsize(ctxt)
-	if objabi.GOARCH == "arm64" {
+	if buildcfg.GOARCH == "arm64" {
 		// need extra 8 bytes below SP to save FP
 		ch.limit -= 8
 	}
diff --git a/src/cmd/link/internal/ld/macho.go b/src/cmd/link/internal/ld/macho.go
index 4c55c5761f..98c9a32f4d 100644
--- a/src/cmd/link/internal/ld/macho.go
+++ b/src/cmd/link/internal/ld/macho.go
@@ -15,6 +15,7 @@ import (
 	"debug/macho"
 	"encoding/binary"
 	"fmt"
+	"internal/buildcfg"
 	"io"
 	"os"
 	"sort"
@@ -945,12 +946,12 @@ func collectmachosyms(ctxt *Link) {
 			if machoPlatform == PLATFORM_MACOS {
 				switch n := ldr.SymExtname(s); n {
 				case "fdopendir":
-					switch objabi.GOARCH {
+					switch buildcfg.GOARCH {
 					case "amd64":
 						ldr.SetSymExtname(s, n+"$INODE64")
 					}
 				case "readdir_r", "getfsstat":
-					switch objabi.GOARCH {
+					switch buildcfg.GOARCH {
 					case "amd64":
 						ldr.SetSymExtname(s, n+"$INODE64")
 					}
diff --git a/src/cmd/link/internal/ld/main.go b/src/cmd/link/internal/ld/main.go
index 1e3c3bdff7..7ab9ca7d10 100644
--- a/src/cmd/link/internal/ld/main.go
+++ b/src/cmd/link/internal/ld/main.go
@@ -37,6 +37,7 @@ import (
 	"cmd/internal/sys"
 	"cmd/link/internal/benchmark"
 	"flag"
+	"internal/buildcfg"
 	"log"
 	"os"
 	"runtime"
@@ -118,14 +119,14 @@ func Main(arch *sys.Arch, theArch Arch) {
 	addstrdata1(ctxt, "runtime.defaultGOROOT="+final)
 	addstrdata1(ctxt, "cmd/internal/objabi.defaultGOROOT="+final)
 
-	buildVersion := objabi.Version
-	if goexperiment := objabi.GOEXPERIMENT(); goexperiment != "" {
+	buildVersion := buildcfg.Version
+	if goexperiment := buildcfg.GOEXPERIMENT(); goexperiment != "" {
 		buildVersion += " X:" + goexperiment
 	}
 	addstrdata1(ctxt, "runtime.buildVersion="+buildVersion)
 
 	// TODO(matloob): define these above and then check flag values here
-	if ctxt.Arch.Family == sys.AMD64 && objabi.GOOS == "plan9" {
+	if ctxt.Arch.Family == sys.AMD64 && buildcfg.GOOS == "plan9" {
 		flag.BoolVar(&flag8, "8", false, "use 64-bit addresses in symbol table")
 	}
 	flagHeadType := flag.String("H", "", "set header `type`")
@@ -159,7 +160,7 @@ func Main(arch *sys.Arch, theArch Arch) {
 		}
 	}
 	if ctxt.HeadType == objabi.Hunknown {
-		ctxt.HeadType.Set(objabi.GOOS)
+		ctxt.HeadType.Set(buildcfg.GOOS)
 	}
 
 	if !*flagAslr && ctxt.BuildMode != BuildModeCShared {
@@ -255,7 +256,7 @@ func Main(arch *sys.Arch, theArch Arch) {
 
 	bench.Start("dostrdata")
 	ctxt.dostrdata()
-	if objabi.Experiment.FieldTrack {
+	if buildcfg.Experiment.FieldTrack {
 		bench.Start("fieldtrack")
 		fieldtrack(ctxt.Arch, ctxt.loader)
 	}
diff --git a/src/cmd/link/internal/ld/pcln.go b/src/cmd/link/internal/ld/pcln.go
index 61b64f4f5a..79ad9d73e9 100644
--- a/src/cmd/link/internal/ld/pcln.go
+++ b/src/cmd/link/internal/ld/pcln.go
@@ -11,6 +11,7 @@ import (
 	"cmd/link/internal/loader"
 	"cmd/link/internal/sym"
 	"fmt"
+	"internal/buildcfg"
 	"os"
 	"path/filepath"
 )
@@ -879,7 +880,7 @@ func (ctxt *Link) pclntab(container loader.Bitmap) *pclntab {
 }
 
 func gorootFinal() string {
-	root := objabi.GOROOT
+	root := buildcfg.GOROOT
 	if final := os.Getenv("GOROOT_FINAL"); final != "" {
 		root = final
 	}
diff --git a/src/cmd/link/internal/ld/pe.go b/src/cmd/link/internal/ld/pe.go
index 3ed8943828..729b6b2443 100644
--- a/src/cmd/link/internal/ld/pe.go
+++ b/src/cmd/link/internal/ld/pe.go
@@ -15,6 +15,7 @@ import (
 	"debug/pe"
 	"encoding/binary"
 	"fmt"
+	"internal/buildcfg"
 	"sort"
 	"strconv"
 	"strings"
@@ -481,9 +482,9 @@ func (f *peFile) addInitArray(ctxt *Link) *peSection {
 	// that this will need to grow in the future.
 	var size int
 	var alignment uint32
-	switch objabi.GOARCH {
+	switch buildcfg.GOARCH {
 	default:
-		Exitf("peFile.addInitArray: unsupported GOARCH=%q\n", objabi.GOARCH)
+		Exitf("peFile.addInitArray: unsupported GOARCH=%q\n", buildcfg.GOARCH)
 	case "386", "arm":
 		size = 4
 		alignment = IMAGE_SCN_ALIGN_4BYTES
@@ -499,7 +500,7 @@ func (f *peFile) addInitArray(ctxt *Link) *peSection {
 
 	init_entry := ctxt.loader.Lookup(*flagEntrySymbol, 0)
 	addr := uint64(ctxt.loader.SymValue(init_entry)) - ctxt.loader.SymSect(init_entry).Vaddr
-	switch objabi.GOARCH {
+	switch buildcfg.GOARCH {
 	case "386", "arm":
 		ctxt.Out.Write32(uint32(addr))
 	case "amd64", "arm64":
@@ -610,9 +611,9 @@ dwarfLoop:
 		dottext := ldr.Lookup(".text", 0)
 		ctxt.Out.Write32(0)
 		ctxt.Out.Write32(uint32(ldr.SymDynid(dottext)))
-		switch objabi.GOARCH {
+		switch buildcfg.GOARCH {
 		default:
-			ctxt.Errorf(dottext, "unknown architecture for PE: %q\n", objabi.GOARCH)
+			ctxt.Errorf(dottext, "unknown architecture for PE: %q\n", buildcfg.GOARCH)
 		case "386":
 			ctxt.Out.Write16(IMAGE_REL_I386_DIR32)
 		case "amd64":
diff --git a/src/cmd/link/internal/ld/sym.go b/src/cmd/link/internal/ld/sym.go
index 75489720cc..72639962e2 100644
--- a/src/cmd/link/internal/ld/sym.go
+++ b/src/cmd/link/internal/ld/sym.go
@@ -36,6 +36,7 @@ import (
 	"cmd/internal/sys"
 	"cmd/link/internal/loader"
 	"cmd/link/internal/sym"
+	"internal/buildcfg"
 	"log"
 	"runtime"
 )
@@ -53,8 +54,8 @@ func linknew(arch *sys.Arch) *Link {
 		generatorSyms: make(map[loader.Sym]generatorFunc),
 	}
 
-	if objabi.GOARCH != arch.Name {
-		log.Fatalf("invalid objabi.GOARCH %s (want %s)", objabi.GOARCH, arch.Name)
+	if buildcfg.GOARCH != arch.Name {
+		log.Fatalf("invalid buildcfg.GOARCH %s (want %s)", buildcfg.GOARCH, arch.Name)
 	}
 
 	AtExit(func() {
diff --git a/src/cmd/link/internal/ld/symtab.go b/src/cmd/link/internal/ld/symtab.go
index dcb9d7eb48..013f7b55b6 100644
--- a/src/cmd/link/internal/ld/symtab.go
+++ b/src/cmd/link/internal/ld/symtab.go
@@ -37,6 +37,7 @@ import (
 	"cmd/link/internal/sym"
 	"debug/elf"
 	"fmt"
+	"internal/buildcfg"
 	"path/filepath"
 	"strings"
 )
@@ -844,7 +845,7 @@ func mangleABIName(ldr *loader.Loader, x loader.Sym, name string) string {
 	// TODO: avoid the ldr.Lookup calls below by instead using an aux
 	// sym or marker relocation to associate the wrapper with the
 	// wrapped function.
-	if !objabi.Experiment.RegabiWrappers {
+	if !buildcfg.Experiment.RegabiWrappers {
 		return name
 	}
 
diff --git a/src/cmd/link/internal/mips/obj.go b/src/cmd/link/internal/mips/obj.go
index f20597c0f5..5ca7582529 100644
--- a/src/cmd/link/internal/mips/obj.go
+++ b/src/cmd/link/internal/mips/obj.go
@@ -34,11 +34,12 @@ import (
 	"cmd/internal/objabi"
 	"cmd/internal/sys"
 	"cmd/link/internal/ld"
+	"internal/buildcfg"
 )
 
 func Init() (*sys.Arch, ld.Arch) {
 	arch := sys.ArchMIPS
-	if objabi.GOARCH == "mipsle" {
+	if buildcfg.GOARCH == "mipsle" {
 		arch = sys.ArchMIPSLE
 	}
 
diff --git a/src/cmd/link/internal/mips64/obj.go b/src/cmd/link/internal/mips64/obj.go
index 01d89a209c..544e1ef7be 100644
--- a/src/cmd/link/internal/mips64/obj.go
+++ b/src/cmd/link/internal/mips64/obj.go
@@ -34,11 +34,12 @@ import (
 	"cmd/internal/objabi"
 	"cmd/internal/sys"
 	"cmd/link/internal/ld"
+	"internal/buildcfg"
 )
 
 func Init() (*sys.Arch, ld.Arch) {
 	arch := sys.ArchMIPS64
-	if objabi.GOARCH == "mips64le" {
+	if buildcfg.GOARCH == "mips64le" {
 		arch = sys.ArchMIPS64LE
 	}
 
diff --git a/src/cmd/link/internal/ppc64/obj.go b/src/cmd/link/internal/ppc64/obj.go
index ef4393f489..54d4606487 100644
--- a/src/cmd/link/internal/ppc64/obj.go
+++ b/src/cmd/link/internal/ppc64/obj.go
@@ -34,11 +34,12 @@ import (
 	"cmd/internal/objabi"
 	"cmd/internal/sys"
 	"cmd/link/internal/ld"
+	"internal/buildcfg"
 )
 
 func Init() (*sys.Arch, ld.Arch) {
 	arch := sys.ArchPPC64
-	if objabi.GOARCH == "ppc64le" {
+	if buildcfg.GOARCH == "ppc64le" {
 		arch = sys.ArchPPC64LE
 	}
 
diff --git a/src/cmd/link/internal/wasm/asm.go b/src/cmd/link/internal/wasm/asm.go
index 31851fbb56..5bdfdbaee6 100644
--- a/src/cmd/link/internal/wasm/asm.go
+++ b/src/cmd/link/internal/wasm/asm.go
@@ -10,6 +10,7 @@ import (
 	"cmd/link/internal/ld"
 	"cmd/link/internal/loader"
 	"cmd/link/internal/sym"
+	"internal/buildcfg"
 	"io"
 	"regexp"
 )
@@ -506,15 +507,15 @@ func writeProducerSec(ctxt *ld.Link) {
 
 	writeUleb128(ctxt.Out, 2) // number of fields
 
-	writeName(ctxt.Out, "language")     // field name
-	writeUleb128(ctxt.Out, 1)           // number of values
-	writeName(ctxt.Out, "Go")           // value: name
-	writeName(ctxt.Out, objabi.Version) // value: version
+	writeName(ctxt.Out, "language")       // field name
+	writeUleb128(ctxt.Out, 1)             // number of values
+	writeName(ctxt.Out, "Go")             // value: name
+	writeName(ctxt.Out, buildcfg.Version) // value: version
 
 	writeName(ctxt.Out, "processed-by")   // field name
 	writeUleb128(ctxt.Out, 1)             // number of values
 	writeName(ctxt.Out, "Go cmd/compile") // value: name
-	writeName(ctxt.Out, objabi.Version)   // value: version
+	writeName(ctxt.Out, buildcfg.Version) // value: version
 
 	writeSecSize(ctxt, sizeOffset)
 }
diff --git a/src/cmd/link/linkbig_test.go b/src/cmd/link/linkbig_test.go
index 917bd9e8a3..9a4430c162 100644
--- a/src/cmd/link/linkbig_test.go
+++ b/src/cmd/link/linkbig_test.go
@@ -10,8 +10,8 @@ package main
 
 import (
 	"bytes"
-	"cmd/internal/objabi"
 	"fmt"
+	"internal/buildcfg"
 	"internal/testenv"
 	"io/ioutil"
 	"os/exec"
@@ -19,8 +19,8 @@ import (
 )
 
 func TestLargeText(t *testing.T) {
-	if testing.Short() || (objabi.GOARCH != "ppc64le" && objabi.GOARCH != "ppc64" && objabi.GOARCH != "arm") {
-		t.Skipf("Skipping large text section test in short mode or on %s", objabi.GOARCH)
+	if testing.Short() || (buildcfg.GOARCH != "ppc64le" && buildcfg.GOARCH != "ppc64" && buildcfg.GOARCH != "arm") {
+		t.Skipf("Skipping large text section test in short mode or on %s", buildcfg.GOARCH)
 	}
 	testenv.MustHaveGoBuild(t)
 
@@ -42,7 +42,7 @@ func TestLargeText(t *testing.T) {
 		"ppc64le": "\tMOVD\tR0,R3\n",
 		"arm":     "\tMOVW\tR0,R1\n",
 	}
-	inst := instOnArch[objabi.GOARCH]
+	inst := instOnArch[buildcfg.GOARCH]
 	for j := 0; j < FN; j++ {
 		testname := fmt.Sprintf("bigfn%d", j)
 		fmt.Fprintf(&w, "TEXT ·%s(SB),$0\n", testname)
diff --git a/src/cmd/link/main.go b/src/cmd/link/main.go
index 6b4ca9706d..d92478e61e 100644
--- a/src/cmd/link/main.go
+++ b/src/cmd/link/main.go
@@ -5,7 +5,6 @@
 package main
 
 import (
-	"cmd/internal/objabi"
 	"cmd/internal/sys"
 	"cmd/link/internal/amd64"
 	"cmd/link/internal/arm"
@@ -19,6 +18,7 @@ import (
 	"cmd/link/internal/wasm"
 	"cmd/link/internal/x86"
 	"fmt"
+	"internal/buildcfg"
 	"os"
 )
 
@@ -40,9 +40,10 @@ func main() {
 	var arch *sys.Arch
 	var theArch ld.Arch
 
-	switch objabi.GOARCH {
+	buildcfg.Check()
+	switch buildcfg.GOARCH {
 	default:
-		fmt.Fprintf(os.Stderr, "link: unknown architecture %q\n", objabi.GOARCH)
+		fmt.Fprintf(os.Stderr, "link: unknown architecture %q\n", buildcfg.GOARCH)
 		os.Exit(2)
 	case "386":
 		arch, theArch = x86.Init()