Revert "cmd/compile: enable Asan check for global variables"

This reverts CL 321715.

Reason for revert: broke cmd/go.TestScript/install_msan_and_race_require_cgo on several builders.

Change-Id: Ia0392de555d6e973960769a0e4709f0193d16706
Reviewed-on: https://go-review.googlesource.com/c/go/+/401755
Run-TryBot: Bryan Mills <bcmills@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>

17 files changed, 9 insertions, 461 deletions

diff --git a/misc/cgo/testsanitizers/asan_test.go b/misc/cgo/testsanitizers/asan_test.go
index 23392c00f6..ff578ac63e 100644
--- a/misc/cgo/testsanitizers/asan_test.go
+++ b/misc/cgo/testsanitizers/asan_test.go
@@ -22,14 +22,6 @@ func TestASAN(t *testing.T) {
 	if !aSanSupported(goos, goarch) {
 		t.Skipf("skipping on %s/%s; -asan option is not supported.", goos, goarch)
 	}
-	// The current implementation is only compatible with the ASan library from version
-	// v7 to v9 (See the description in src/runtime/asan/asan.go). Therefore, using the
-	// -asan option must use a compatible version of ASan library, which requires that
-	// the gcc version is not less than 7 and the clang version is not less than 4,
-	// otherwise a segmentation fault will occur.
-	if !compilerRequiredAsanVersion() {
-		t.Skipf("skipping: too old version of compiler")
-	}
 
 	t.Parallel()
 	requireOvercommit(t)
diff --git a/misc/cgo/testsanitizers/cc_test.go b/misc/cgo/testsanitizers/cc_test.go
index ee3c3bf28c..05b77932b4 100644
--- a/misc/cgo/testsanitizers/cc_test.go
+++ b/misc/cgo/testsanitizers/cc_test.go
@@ -235,22 +235,6 @@ func compilerSupportsLocation() bool {
 	}
 }
 
-// compilerRequiredAsanVersion reports whether the compiler is the version required by Asan.
-func compilerRequiredAsanVersion() bool {
-	compiler, err := compilerVersion()
-	if err != nil {
-		return false
-	}
-	switch compiler.name {
-	case "gcc":
-		return compiler.major >= 7
-	case "clang":
-		return true
-	default:
-		return false
-	}
-}
-
 type compilerCheck struct {
 	once sync.Once
 	err  error
diff --git a/src/cmd/compile/internal/base/base.go b/src/cmd/compile/internal/base/base.go
index 5e1493e275..39ce8e66f7 100644
--- a/src/cmd/compile/internal/base/base.go
+++ b/src/cmd/compile/internal/base/base.go
@@ -70,7 +70,6 @@ var NoInstrumentPkgs = []string{
 	"runtime/msan",
 	"runtime/asan",
 	"internal/cpu",
-	"buildcfg",
 }
 
 // Don't insert racefuncenter/racefuncexit into the following packages.
diff --git a/src/cmd/compile/internal/gc/obj.go b/src/cmd/compile/internal/gc/obj.go
index fea2df85e5..fe8b6e9d45 100644
--- a/src/cmd/compile/internal/gc/obj.go
+++ b/src/cmd/compile/internal/gc/obj.go
@@ -9,7 +9,6 @@ import (
 	"cmd/compile/internal/ir"
 	"cmd/compile/internal/noder"
 	"cmd/compile/internal/objw"
-	"cmd/compile/internal/pkginit"
 	"cmd/compile/internal/reflectdata"
 	"cmd/compile/internal/staticdata"
 	"cmd/compile/internal/typecheck"
@@ -111,6 +110,7 @@ func dumpCompilerObj(bout *bio.Writer) {
 func dumpdata() {
 	numExterns := len(typecheck.Target.Externs)
 	numDecls := len(typecheck.Target.Decls)
+
 	dumpglobls(typecheck.Target.Externs)
 	reflectdata.CollectPTabs()
 	numExports := len(typecheck.Target.Exports)
@@ -287,20 +287,7 @@ func ggloblnod(nam *ir.Name) {
 	if nam.Type() != nil && !nam.Type().HasPointers() {
 		flags |= obj.NOPTR
 	}
-	size := nam.Type().Size()
-	linkname := nam.Sym().Linkname
-	name := nam.Sym().Name
-
-	// We've skipped linkname'd globals's instrument, so we can skip them here as well.
-	if base.Flag.ASan && linkname == "" && pkginit.InstrumentGlobalsMap[name] != nil {
-		// Write the new size of instrumented global variables that have
-		// trailing redzones into object file.
-		rzSize := pkginit.GetRedzoneSizeForGlobal(size)
-		sizeWithRZ := rzSize + size
-		base.Ctxt.Globl(s, sizeWithRZ, flags)
-	} else {
-		base.Ctxt.Globl(s, size, flags)
-	}
+	base.Ctxt.Globl(s, nam.Type().Size(), flags)
 	if nam.LibfuzzerExtraCounter() {
 		s.Type = objabi.SLIBFUZZER_EXTRA_COUNTER
 	}
diff --git a/src/cmd/compile/internal/noder/noder.go b/src/cmd/compile/internal/noder/noder.go
index c4c2db5f78..9a42b5afd1 100644
--- a/src/cmd/compile/internal/noder/noder.go
+++ b/src/cmd/compile/internal/noder/noder.go
@@ -442,7 +442,7 @@ func parseGoEmbed(args string) ([]string, error) {
 // the name, normally "pkg.init", is altered to "pkg.init.0".
 var renameinitgen int
 
-func Renameinit() *types.Sym {
+func renameinit() *types.Sym {
 	s := typecheck.LookupNum("init.", renameinitgen)
 	renameinitgen++
 	return s
diff --git a/src/cmd/compile/internal/noder/object.go b/src/cmd/compile/internal/noder/object.go
index ee9e0e2680..e8dbaac161 100644
--- a/src/cmd/compile/internal/noder/object.go
+++ b/src/cmd/compile/internal/noder/object.go
@@ -104,7 +104,7 @@ func (g *irgen) obj(obj types2.Object) *ir.Name {
 		var typ *types.Type
 		if recv := sig.Recv(); recv == nil {
 			if obj.Name() == "init" {
-				sym = Renameinit()
+				sym = renameinit()
 			} else {
 				sym = g.sym(obj)
 			}
diff --git a/src/cmd/compile/internal/noder/reader.go b/src/cmd/compile/internal/noder/reader.go
index 10861717f3..1350c22467 100644
--- a/src/cmd/compile/internal/noder/reader.go
+++ b/src/cmd/compile/internal/noder/reader.go
@@ -643,7 +643,7 @@ func (pr *pkgReader) objIdx(idx int, implicits, explicits []*types.Type) ir.Node
 
 	case pkgbits.ObjFunc:
 		if sym.Name == "init" {
-			sym = Renameinit()
+			sym = renameinit()
 		}
 		name := do(ir.ONAME, true)
 		setType(name, r.signature(sym.Pkg, nil))
diff --git a/src/cmd/compile/internal/pkginit/init.go b/src/cmd/compile/internal/pkginit/init.go
index d94482a962..32e95bedc2 100644
--- a/src/cmd/compile/internal/pkginit/init.go
+++ b/src/cmd/compile/internal/pkginit/init.go
@@ -7,7 +7,6 @@ package pkginit
 import (
 	"cmd/compile/internal/base"
 	"cmd/compile/internal/ir"
-	"cmd/compile/internal/noder"
 	"cmd/compile/internal/objw"
 	"cmd/compile/internal/staticinit"
 	"cmd/compile/internal/typecheck"
@@ -84,58 +83,6 @@ func Task() *ir.Name {
 		}
 		deps = append(deps, n.(*ir.Name).Linksym())
 	}
-	if base.Flag.ASan {
-		// Make an initialization function to call runtime.asanregisterglobals to register an
-		// array of instrumented global variables when -asan is enabled. An instrumented global
-		// variable is described by a structure.
-		// See the _asan_global structure declared in src/runtime/asan/asan.go.
-		//
-		// func init {
-		// 		var globals []_asan_global {...}
-		// 		asanregisterglobals(&globals[0], len(globals))
-		// }
-		for _, n := range typecheck.Target.Externs {
-			if canInstrumentGlobal(n) {
-				name := n.Sym().Name
-				InstrumentGlobalsMap[name] = n
-				InstrumentGlobalsSlice = append(InstrumentGlobalsSlice, n)
-			}
-		}
-		ni := len(InstrumentGlobalsMap)
-		if ni != 0 {
-			// Make an init._ function.
-			base.Pos = base.AutogeneratedPos
-			typecheck.DeclContext = ir.PEXTERN
-			name := noder.Renameinit()
-			fnInit := typecheck.DeclFunc(name, ir.NewFuncType(base.Pos, nil, nil, nil))
-
-			// Get an array of intrumented global variables.
-			globals := instrumentGlobals(fnInit)
-
-			// Call runtime.asanregisterglobals function to poison redzones.
-			// runtime.asanregisterglobals(unsafe.Pointer(&globals[0]), ni)
-			asanf := typecheck.NewName(ir.Pkgs.Runtime.Lookup("asanregisterglobals"))
-			ir.MarkFunc(asanf)
-			asanf.SetType(types.NewSignature(types.NoPkg, nil, nil, []*types.Field{
-				types.NewField(base.Pos, nil, types.Types[types.TUNSAFEPTR]),
-				types.NewField(base.Pos, nil, types.Types[types.TUINTPTR]),
-			}, nil))
-			asancall := ir.NewCallExpr(base.Pos, ir.OCALL, asanf, nil)
-			asancall.Args.Append(typecheck.ConvNop(typecheck.NodAddr(
-				ir.NewIndexExpr(base.Pos, globals, ir.NewInt(0))), types.Types[types.TUNSAFEPTR]))
-			asancall.Args.Append(typecheck.ConvNop(ir.NewInt(int64(ni)), types.Types[types.TUINTPTR]))
-
-			fnInit.Body.Append(asancall)
-			typecheck.FinishFuncBody()
-			typecheck.Func(fnInit)
-			ir.CurFunc = fnInit
-			typecheck.Stmts(fnInit.Body)
-			ir.CurFunc = nil
-
-			typecheck.Target.Decls = append(typecheck.Target.Decls, fnInit)
-			typecheck.Target.Inits = append(typecheck.Target.Inits, fnInit)
-		}
-	}
 
 	// Record user init functions.
 	for _, fn := range typecheck.Target.Inits {
diff --git a/src/cmd/compile/internal/pkginit/initAsanGlobals.go b/src/cmd/compile/internal/pkginit/initAsanGlobals.go
deleted file mode 100644
index 7276791d6e..0000000000
--- a/src/cmd/compile/internal/pkginit/initAsanGlobals.go
+++ /dev/null
@@ -1,241 +0,0 @@
-// Copyright 2022 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package pkginit
-
-import (
-	"strings"
-
-	"cmd/compile/internal/base"
-	"cmd/compile/internal/ir"
-	"cmd/compile/internal/typecheck"
-	"cmd/compile/internal/types"
-	"cmd/internal/src"
-)
-
-// instrumentGlobals declares a global array of _asan_global structures and initializes it.
-func instrumentGlobals(fn *ir.Func) *ir.Name {
-	asanGlobalStruct, asanLocationStruct, defStringstruct := createtypes()
-	lname := typecheck.Lookup
-	tconv := typecheck.ConvNop
-	// Make a global array of asanGlobalStruct type.
-	// var asanglobals []asanGlobalStruct
-	arraytype := types.NewArray(asanGlobalStruct, int64(len(InstrumentGlobalsMap)))
-	symG := lname(".asanglobals")
-	globals := typecheck.NewName(symG)
-	globals.SetType(arraytype)
-	globals.Class = ir.PEXTERN
-	symG.Def = globals
-	typecheck.Target.Externs = append(typecheck.Target.Externs, globals)
-	// Make a global array of asanLocationStruct type.
-	// var asanL []asanLocationStruct
-	arraytype = types.NewArray(asanLocationStruct, int64(len(InstrumentGlobalsMap)))
-	symL := lname(".asanL")
-	asanlocation := typecheck.NewName(symL)
-	asanlocation.SetType(arraytype)
-	asanlocation.Class = ir.PEXTERN
-	symL.Def = asanlocation
-	typecheck.Target.Externs = append(typecheck.Target.Externs, asanlocation)
-	// Make three global string variables to pass the global name and module name
-	// and the name of the source file that defines it.
-	// var asanName string
-	// var asanModulename string
-	// var asanFilename string
-	symL = lname(".asanName")
-	asanName := typecheck.NewName(symL)
-	asanName.SetType(types.Types[types.TSTRING])
-	asanName.Class = ir.PEXTERN
-	symL.Def = asanName
-	typecheck.Target.Externs = append(typecheck.Target.Externs, asanName)
-
-	symL = lname(".asanModulename")
-	asanModulename := typecheck.NewName(symL)
-	asanModulename.SetType(types.Types[types.TSTRING])
-	asanModulename.Class = ir.PEXTERN
-	symL.Def = asanModulename
-	typecheck.Target.Externs = append(typecheck.Target.Externs, asanModulename)
-
-	symL = lname(".asanFilename")
-	asanFilename := typecheck.NewName(symL)
-	asanFilename.SetType(types.Types[types.TSTRING])
-	asanFilename.Class = ir.PEXTERN
-	symL.Def = asanFilename
-	typecheck.Target.Externs = append(typecheck.Target.Externs, asanFilename)
-
-	var init ir.Nodes
-	var c ir.Node
-	// globals[i].odrIndicator = 0 is the default, no need to set it explicitly here.
-	for i, n := range InstrumentGlobalsSlice {
-		setField := func(f string, val ir.Node, i int) {
-			r := ir.NewAssignStmt(base.Pos, ir.NewSelectorExpr(base.Pos, ir.ODOT,
-				ir.NewIndexExpr(base.Pos, globals, ir.NewInt(int64(i))), lname(f)), val)
-			init.Append(typecheck.Stmt(r))
-		}
-		// globals[i].beg = uintptr(unsafe.Pointer(&n))
-		c = tconv(typecheck.NodAddr(n), types.Types[types.TUNSAFEPTR])
-		c = tconv(c, types.Types[types.TUINTPTR])
-		setField("beg", c, i)
-		// Assign globals[i].size.
-		g := n.(*ir.Name)
-		size := g.Type().Size()
-		c = tconv(ir.NewInt(size), types.Types[types.TUINTPTR])
-		setField("size", c, i)
-		// Assign globals[i].sizeWithRedzone.
-		rzSize := GetRedzoneSizeForGlobal(size)
-		sizeWithRz := rzSize + size
-		c = tconv(ir.NewInt(sizeWithRz), types.Types[types.TUINTPTR])
-		setField("sizeWithRedzone", c, i)
-		// The C string type is terminated by a null charactor "\0", Go should use three-digit
-		// octal "\000" or two-digit hexadecimal "\x00" to create null terminated string.
-		// asanName = symbol's linkname + "\000"
-		// globals[i].name = (*defString)(unsafe.Pointer(&asanName)).data
-		name := g.Linksym().Name
-		init.Append(typecheck.Stmt(ir.NewAssignStmt(base.Pos, asanName, ir.NewString(name+"\000"))))
-		c = tconv(typecheck.NodAddr(asanName), types.Types[types.TUNSAFEPTR])
-		c = tconv(c, types.NewPtr(defStringstruct))
-		c = ir.NewSelectorExpr(base.Pos, ir.ODOT, c, lname("data"))
-		setField("name", c, i)
-
-		// Set the name of package being compiled as a unique identifier of a module.
-		// asanModulename = pkgName + "\000"
-		init.Append(typecheck.Stmt(ir.NewAssignStmt(base.Pos, asanModulename, ir.NewString(types.LocalPkg.Name+"\000"))))
-		c = tconv(typecheck.NodAddr(asanModulename), types.Types[types.TUNSAFEPTR])
-		c = tconv(c, types.NewPtr(defStringstruct))
-		c = ir.NewSelectorExpr(base.Pos, ir.ODOT, c, lname("data"))
-		setField("moduleName", c, i)
-		// Assign asanL[i].filename, asanL[i].line, asanL[i].column
-		// and assign globals[i].location = uintptr(unsafe.Pointer(&asanL[i]))
-		asanLi := ir.NewIndexExpr(base.Pos, asanlocation, ir.NewInt(int64(i)))
-		filename := ir.NewString(base.Ctxt.PosTable.Pos(n.Pos()).Filename() + "\000")
-		init.Append(typecheck.Stmt(ir.NewAssignStmt(base.Pos, asanFilename, filename)))
-		c = tconv(typecheck.NodAddr(asanFilename), types.Types[types.TUNSAFEPTR])
-		c = tconv(c, types.NewPtr(defStringstruct))
-		c = ir.NewSelectorExpr(base.Pos, ir.ODOT, c, lname("data"))
-		init.Append(typecheck.Stmt(ir.NewAssignStmt(base.Pos, ir.NewSelectorExpr(base.Pos, ir.ODOT, asanLi, lname("filename")), c)))
-		line := ir.NewInt(int64(n.Pos().Line()))
-		init.Append(typecheck.Stmt(ir.NewAssignStmt(base.Pos, ir.NewSelectorExpr(base.Pos, ir.ODOT, asanLi, lname("line")), line)))
-		col := ir.NewInt(int64(n.Pos().Col()))
-		init.Append(typecheck.Stmt(ir.NewAssignStmt(base.Pos, ir.NewSelectorExpr(base.Pos, ir.ODOT, asanLi, lname("column")), col)))
-		c = tconv(typecheck.NodAddr(asanLi), types.Types[types.TUNSAFEPTR])
-		c = tconv(c, types.Types[types.TUINTPTR])
-		setField("sourceLocation", c, i)
-	}
-	fn.Body.Append(init...)
-	return globals
-}
-
-// createtypes creates the asanGlobal, asanLocation and defString struct type.
-// Go compiler does not refer to the C types, we represent the struct field
-// by a uintptr, then use type conversion to make copies of the data.
-// E.g., (*defString)(asanGlobal.name).data to C string.
-//
-// Keep in sync with src/runtime/asan/asan.go.
-// type asanGlobal struct {
-//	beg               uintptr
-//	size              uintptr
-//	size_with_redzone uintptr
-//	name              uintptr
-//	moduleName        uintptr
-//	hasDynamicInit    uintptr
-//	sourceLocation    uintptr
-//	odrIndicator      uintptr
-// }
-//
-// type asanLocation struct {
-//	filename uintptr
-//	line     int32
-//	column   int32
-// }
-//
-// defString is synthesized struct type meant to capture the underlying
-// implementations of string.
-// type defString struct {
-//	data uintptr
-//	len  uintptr
-// }
-
-func createtypes() (*types.Type, *types.Type, *types.Type) {
-	up := types.Types[types.TUINTPTR]
-	i32 := types.Types[types.TINT32]
-	fname := typecheck.Lookup
-	nxp := src.NoXPos
-	nfield := types.NewField
-	asanGlobal := types.NewStruct(types.NoPkg, []*types.Field{
-		nfield(nxp, fname("beg"), up),
-		nfield(nxp, fname("size"), up),
-		nfield(nxp, fname("sizeWithRedzone"), up),
-		nfield(nxp, fname("name"), up),
-		nfield(nxp, fname("moduleName"), up),
-		nfield(nxp, fname("hasDynamicInit"), up),
-		nfield(nxp, fname("sourceLocation"), up),
-		nfield(nxp, fname("odrIndicator"), up),
-	})
-	types.CalcSize(asanGlobal)
-
-	asanLocation := types.NewStruct(types.NoPkg, []*types.Field{
-		nfield(nxp, fname("filename"), up),
-		nfield(nxp, fname("line"), i32),
-		nfield(nxp, fname("column"), i32),
-	})
-	types.CalcSize(asanLocation)
-
-	defString := types.NewStruct(types.NoPkg, []*types.Field{
-		types.NewField(nxp, fname("data"), up),
-		types.NewField(nxp, fname("len"), up),
-	})
-	types.CalcSize(defString)
-
-	return asanGlobal, asanLocation, defString
-}
-
-// Calculate redzone for globals.
-func GetRedzoneSizeForGlobal(size int64) int64 {
-	maxRZ := int64(1 << 18)
-	minRZ := int64(32)
-	redZone := (size / minRZ / 4) * minRZ
-	switch {
-	case redZone > maxRZ:
-		redZone = maxRZ
-	case redZone < minRZ:
-		redZone = minRZ
-	}
-	// Round up to multiple of minRZ.
-	if size%minRZ != 0 {
-		redZone += minRZ - (size % minRZ)
-	}
-	return redZone
-}
-
-// InstrumentGlobalsMap contains only package-local (and unlinknamed from somewhere else)
-// globals.
-// And the key is the object name. For example, in package p, a global foo would be in this
-// map as "foo".
-// Consider range over maps is nondeterministic, make a slice to hold all the values in the
-// InstrumentGlobalsMap and iterate over the InstrumentGlobalsSlice.
-var InstrumentGlobalsMap = make(map[string]ir.Node)
-var InstrumentGlobalsSlice = make([]ir.Node, 0, 0)
-
-func canInstrumentGlobal(g ir.Node) bool {
-	if g.Op() != ir.ONAME {
-		return false
-	}
-	n := g.(*ir.Name)
-	if n.Class == ir.PFUNC {
-		return false
-	}
-	if n.Sym().Pkg != types.LocalPkg {
-		return false
-	}
-	// Do not instrument any _cgo_ related global variables, because they are declared in C code.
-	if strings.Contains(n.Sym().Name, "cgo") {
-		return false
-	}
-
-	// Do not instrument globals that are linknamed, because their home package will do the work.
-	if n.Sym().Linkname != "" {
-		return false
-	}
-
-	return true
-}
diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index 7193ab6c7e..6fdb4f93a3 100644
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -123,8 +123,6 @@
 //	-asan
 //		enable interoperation with address sanitizer.
 //		Supported only on linux/arm64, linux/amd64.
-//		Supported only on linux/amd64 or linux/arm64 and only with GCC 7 and higher
-//		or Clang/LLVM 4 and higher.
 //	-v
 //		print the names of packages as they are compiled.
 //	-work
diff --git a/src/cmd/go/internal/work/build.go b/src/cmd/go/internal/work/build.go
index d69eb7a9bf..e9a8ee6cb3 100644
--- a/src/cmd/go/internal/work/build.go
+++ b/src/cmd/go/internal/work/build.go
@@ -79,8 +79,6 @@ and test commands:
 	-asan
 		enable interoperation with address sanitizer.
 		Supported only on linux/arm64, linux/amd64.
-		Supported only on linux/amd64 or linux/arm64 and only with GCC 7 and higher
-		or Clang/LLVM 4 and higher.
 	-v
 		print the names of packages as they are compiled.
 	-work
diff --git a/src/cmd/go/internal/work/init.go b/src/cmd/go/internal/work/init.go
index 22e29e87f4..26192ecaed 100644
--- a/src/cmd/go/internal/work/init.go
+++ b/src/cmd/go/internal/work/init.go
@@ -14,13 +14,9 @@ import (
 	"cmd/internal/quoted"
 	"cmd/internal/sys"
 	"fmt"
-	exec "internal/execabs"
 	"os"
 	"path/filepath"
-	"regexp"
 	"runtime"
-	"strconv"
-	"strings"
 )
 
 func BuildInit() {
@@ -111,15 +107,6 @@ func instrumentInit() {
 		base.SetExitStatus(2)
 		base.Exit()
 	}
-	// The current implementation is only compatible with the ASan library from version
-	// v7 to v9 (See the description in src/runtime/asan/asan.go). Therefore, using the
-	// -asan option must use a compatible version of ASan library, which requires that
-	// the gcc version is not less than 7 and the clang version is not less than 4,
-	// otherwise a segmentation fault will occur.
-	if cfg.BuildASan {
-		compilerRequiredAsanVersion()
-	}
-
 	mode := "race"
 	if cfg.BuildMSan {
 		mode = "msan"
@@ -323,47 +310,3 @@ func buildModeInit() {
 		}
 	}
 }
-
-// compilerRequiredAsanVersion checks whether the compiler is the version required by Asan.
-func compilerRequiredAsanVersion() {
-	cc := os.Getenv("CC")
-	isgcc := false
-	if strings.HasPrefix(cc, "gcc") {
-		isgcc = true
-	} else if !strings.HasPrefix(cc, "clang") {
-		fmt.Fprintf(os.Stderr, "-asan requires C compiler is gcc or clang, not %s", cc)
-		base.SetExitStatus(2)
-		base.Exit()
-	}
-	out, err := exec.Command(cc, "-v").CombinedOutput()
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "-asan fails to check C compiler %s version: %v", cc, err)
-		base.SetExitStatus(2)
-		base.Exit()
-	}
-	re := regexp.MustCompile(`version ([0-9]+)\.([0-9]+)\.([0-9]+)`)
-	matches := re.FindSubmatch(out)
-	if len(matches) < 3 {
-		fmt.Fprintf(os.Stderr, "-asan fails to check C compiler %s version: %s", cc, out)
-	}
-	major, err1 := strconv.Atoi(string(matches[1]))
-	minor, err2 := strconv.Atoi(string(matches[2]))
-	if err1 != nil || err2 != nil {
-		fmt.Fprintf(os.Stderr, "-asan fails to check C compiler %s version: %v, %v", cc, err1, err2)
-		base.SetExitStatus(2)
-		base.Exit()
-	}
-	if isgcc {
-		if major < 7 {
-			fmt.Fprintf(os.Stderr, "-asan is not supported with gcc %d.%d; requires gcc 7 or later", major, minor)
-			base.SetExitStatus(2)
-			base.Exit()
-		}
-	} else {
-		if major < 4 {
-			fmt.Fprintf(os.Stderr, "-asan is not supported with clang %d.%d; requires clang 4 or later", major, minor)
-			base.SetExitStatus(2)
-			base.Exit()
-		}
-	}
-}
diff --git a/src/runtime/asan.go b/src/runtime/asan.go
index 25b83277e6..8c41e418f7 100644
--- a/src/runtime/asan.go
+++ b/src/runtime/asan.go
@@ -55,13 +55,9 @@ func asanunpoison(addr unsafe.Pointer, sz uintptr)
 //go:noescape
 func asanpoison(addr unsafe.Pointer, sz uintptr)
 
-//go:noescape
-func asanregisterglobals(addr unsafe.Pointer, n uintptr)
-
 // These are called from asan_GOARCH.s
 //
 //go:cgo_import_static __asan_read_go
 //go:cgo_import_static __asan_write_go
 //go:cgo_import_static __asan_unpoison_go
 //go:cgo_import_static __asan_poison_go
-//go:cgo_import_static __asan_register_globals_go
diff --git a/src/runtime/asan/asan.go b/src/runtime/asan/asan.go
index 3e41d60d93..bab2362c51 100644
--- a/src/runtime/asan/asan.go
+++ b/src/runtime/asan/asan.go
@@ -34,43 +34,5 @@ void __asan_poison_go(void *addr, uintptr_t sz) {
 	__asan_poison_memory_region(addr, sz);
 }
 
-// Keep in sync with the defination in compiler-rt
-// https://github.com/llvm/llvm-project/blob/main/compiler-rt/lib/asan/asan_interface_internal.h#L41
-// This structure is used to describe the source location of
-// a place where global was defined.
-struct _asan_global_source_location {
-	const char *filename;
-	int line_no;
-	int column_no;
-};
-
-// Keep in sync with the defination in compiler-rt
-// https://github.com/llvm/llvm-project/blob/main/compiler-rt/lib/asan/asan_interface_internal.h#L48
-// So far, the current implementation is only compatible with the ASan library from version v7 to v9.
-// https://github.com/llvm/llvm-project/blob/main/compiler-rt/lib/asan/asan_init_version.h
-// This structure describes an instrumented global variable.
-//
-// TODO: If a later version of the ASan library changes __asan_global or __asan_global_source_location
-// structure, we need to make the same changes.
-struct _asan_global {
-	uintptr_t beg;
-	uintptr_t size;
-	uintptr_t size_with_redzone;
-	const char *name;
-	const char *module_name;
-	uintptr_t has_dynamic_init;
-	struct _asan_global_source_location *location;
-	uintptr_t odr_indicator;
-};
-
-
-extern void __asan_register_globals(void*, long int);
-
-// Register global variables.
-// The 'globals' is an array of structures describing 'n' globals.
-void __asan_register_globals_go(void *addr, uintptr_t n) {
-	struct _asan_global *globals = (struct _asan_global *)(addr);
-	__asan_register_globals(globals, n);
-}
 */
 import "C"
diff --git a/src/runtime/asan0.go b/src/runtime/asan0.go
index 0948786200..d5478d6bee 100644
--- a/src/runtime/asan0.go
+++ b/src/runtime/asan0.go
@@ -16,8 +16,7 @@ const asanenabled = false
 
 // Because asanenabled is false, none of these functions should be called.
 
-func asanread(addr unsafe.Pointer, sz uintptr)            { throw("asan") }
-func asanwrite(addr unsafe.Pointer, sz uintptr)           { throw("asan") }
-func asanunpoison(addr unsafe.Pointer, sz uintptr)        { throw("asan") }
-func asanpoison(addr unsafe.Pointer, sz uintptr)          { throw("asan") }
-func asanregisterglobals(addr unsafe.Pointer, sz uintptr) { throw("asan") }
+func asanread(addr unsafe.Pointer, sz uintptr)     { throw("asan") }
+func asanwrite(addr unsafe.Pointer, sz uintptr)    { throw("asan") }
+func asanunpoison(addr unsafe.Pointer, sz uintptr) { throw("asan") }
+func asanpoison(addr unsafe.Pointer, sz uintptr)   { throw("asan") }
diff --git a/src/runtime/asan_amd64.s b/src/runtime/asan_amd64.s
index 0489aa86dd..3857350020 100644
--- a/src/runtime/asan_amd64.s
+++ b/src/runtime/asan_amd64.s
@@ -61,14 +61,6 @@ TEXT	runtime·asanpoison(SB), NOSPLIT, $0-16
 	MOVQ	$__asan_poison_go(SB), AX
 	JMP	asancall<>(SB)
 
-// func runtime·asanregisterglobals(addr unsafe.Pointer, n uintptr)
-TEXT	runtime·asanregisterglobals(SB), NOSPLIT, $0-16
-	MOVD	addr+0(FP), RARG0
-	MOVD	size+8(FP), RARG1
-	// void __asan_register_globals_go(void *addr, uintptr_t n);
-	MOVD	$__asan_register_globals_go(SB), AX
-	JMP	asancall<>(SB)
-
 // Switches SP to g0 stack and calls (AX). Arguments already set.
 TEXT	asancall<>(SB), NOSPLIT, $0-0
 	get_tls(R12)
diff --git a/src/runtime/asan_arm64.s b/src/runtime/asan_arm64.s
index 697c98206e..5ed03c932b 100644
--- a/src/runtime/asan_arm64.s
+++ b/src/runtime/asan_arm64.s
@@ -50,14 +50,6 @@ TEXT	runtime·asanpoison(SB), NOSPLIT, $0-16
 	MOVD	$__asan_poison_go(SB), FARG
 	JMP	asancall<>(SB)
 
-// func runtime·asanregisterglobals(addr unsafe.Pointer, n uintptr)
-TEXT	runtime·asanregisterglobals(SB), NOSPLIT, $0-16
-	MOVD	addr+0(FP), RARG0
-	MOVD	size+8(FP), RARG1
-	// void __asan_register_globals_go(void *addr, uintptr_t n);
-	MOVD	$__asan_register_globals_go(SB), FARG
-	JMP	asancall<>(SB)
-
 // Switches SP to g0 stack and calls (FARG). Arguments already set.
 TEXT	asancall<>(SB), NOSPLIT, $0-0
 	MOVD	RSP, R19                  // callee-saved