[dev.fuzz] all: merge master into dev.fuzz

Change-Id: I5d8c8329ccc9d747bd81ade6b1cb7cb8ae2e94b2

34 files changed, 1048 insertions, 158 deletions

diff --git a/misc/cgo/errors/badsym_test.go b/misc/cgo/errors/badsym_test.go
new file mode 100644
index 0000000000..b2701bf922
--- /dev/null
+++ b/misc/cgo/errors/badsym_test.go
@@ -0,0 +1,216 @@
+// Copyright 2020 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 errorstest
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+	"unicode"
+)
+
+// A manually modified object file could pass unexpected characters
+// into the files generated by cgo.
+
+const magicInput = "abcdefghijklmnopqrstuvwxyz0123"
+const magicReplace = "\n//go:cgo_ldflag \"-badflag\"\n//"
+
+const cSymbol = "BadSymbol" + magicInput + "Name"
+const cDefSource = "int " + cSymbol + " = 1;"
+const cRefSource = "extern int " + cSymbol + "; int F() { return " + cSymbol + "; }"
+
+// goSource is the source code for the trivial Go file we use.
+// We will replace TMPDIR with the temporary directory name.
+const goSource = `
+package main
+
+// #cgo LDFLAGS: TMPDIR/cbad.o TMPDIR/cbad.so
+// extern int F();
+import "C"
+
+func main() {
+	println(C.F())
+}
+`
+
+func TestBadSymbol(t *testing.T) {
+	dir := t.TempDir()
+
+	mkdir := func(base string) string {
+		ret := filepath.Join(dir, base)
+		if err := os.Mkdir(ret, 0755); err != nil {
+			t.Fatal(err)
+		}
+		return ret
+	}
+
+	cdir := mkdir("c")
+	godir := mkdir("go")
+
+	makeFile := func(mdir, base, source string) string {
+		ret := filepath.Join(mdir, base)
+		if err := ioutil.WriteFile(ret, []byte(source), 0644); err != nil {
+			t.Fatal(err)
+		}
+		return ret
+	}
+
+	cDefFile := makeFile(cdir, "cdef.c", cDefSource)
+	cRefFile := makeFile(cdir, "cref.c", cRefSource)
+
+	ccCmd := cCompilerCmd(t)
+
+	cCompile := func(arg, base, src string) string {
+		out := filepath.Join(cdir, base)
+		run := append(ccCmd, arg, "-o", out, src)
+		output, err := exec.Command(run[0], run[1:]...).CombinedOutput()
+		if err != nil {
+			t.Log(run)
+			t.Logf("%s", output)
+			t.Fatal(err)
+		}
+		if err := os.Remove(src); err != nil {
+			t.Fatal(err)
+		}
+		return out
+	}
+
+	// Build a shared library that defines a symbol whose name
+	// contains magicInput.
+
+	cShared := cCompile("-shared", "c.so", cDefFile)
+
+	// Build an object file that refers to the symbol whose name
+	// contains magicInput.
+
+	cObj := cCompile("-c", "c.o", cRefFile)
+
+	// Rewrite the shared library and the object file, replacing
+	// magicInput with magicReplace. This will have the effect of
+	// introducing a symbol whose name looks like a cgo command.
+	// The cgo tool will use that name when it generates the
+	// _cgo_import.go file, thus smuggling a magic //go:cgo_ldflag
+	// pragma into a Go file. We used to not check the pragmas in
+	// _cgo_import.go.
+
+	rewrite := func(from, to string) {
+		obj, err := ioutil.ReadFile(from)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if bytes.Count(obj, []byte(magicInput)) == 0 {
+			t.Fatalf("%s: did not find magic string", from)
+		}
+
+		if len(magicInput) != len(magicReplace) {
+			t.Fatalf("internal test error: different magic lengths: %d != %d", len(magicInput), len(magicReplace))
+		}
+
+		obj = bytes.ReplaceAll(obj, []byte(magicInput), []byte(magicReplace))
+
+		if err := ioutil.WriteFile(to, obj, 0644); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	cBadShared := filepath.Join(godir, "cbad.so")
+	rewrite(cShared, cBadShared)
+
+	cBadObj := filepath.Join(godir, "cbad.o")
+	rewrite(cObj, cBadObj)
+
+	goSourceBadObject := strings.ReplaceAll(goSource, "TMPDIR", godir)
+	makeFile(godir, "go.go", goSourceBadObject)
+
+	makeFile(godir, "go.mod", "module badsym")
+
+	// Try to build our little package.
+	cmd := exec.Command("go", "build", "-ldflags=-v")
+	cmd.Dir = godir
+	output, err := cmd.CombinedOutput()
+
+	// The build should fail, but we want it to fail because we
+	// detected the error, not because we passed a bad flag to the
+	// C linker.
+
+	if err == nil {
+		t.Errorf("go build succeeded unexpectedly")
+	}
+
+	t.Logf("%s", output)
+
+	for _, line := range bytes.Split(output, []byte("\n")) {
+		if bytes.Contains(line, []byte("dynamic symbol")) && bytes.Contains(line, []byte("contains unsupported character")) {
+			// This is the error from cgo.
+			continue
+		}
+
+		// We passed -ldflags=-v to see the external linker invocation,
+		// which should not include -badflag.
+		if bytes.Contains(line, []byte("-badflag")) {
+			t.Error("output should not mention -badflag")
+		}
+
+		// Also check for compiler errors, just in case.
+		// GCC says "unrecognized command line option".
+		// clang says "unknown argument".
+		if bytes.Contains(line, []byte("unrecognized")) || bytes.Contains(output, []byte("unknown")) {
+			t.Error("problem should have been caught before invoking C linker")
+		}
+	}
+}
+
+func cCompilerCmd(t *testing.T) []string {
+	cc := []string{goEnv(t, "CC")}
+
+	out := goEnv(t, "GOGCCFLAGS")
+	quote := '\000'
+	start := 0
+	lastSpace := true
+	backslash := false
+	s := string(out)
+	for i, c := range s {
+		if quote == '\000' && unicode.IsSpace(c) {
+			if !lastSpace {
+				cc = append(cc, s[start:i])
+				lastSpace = true
+			}
+		} else {
+			if lastSpace {
+				start = i
+				lastSpace = false
+			}
+			if quote == '\000' && !backslash && (c == '"' || c == '\'') {
+				quote = c
+				backslash = false
+			} else if !backslash && quote == c {
+				quote = '\000'
+			} else if (quote == '\000' || quote == '"') && !backslash && c == '\\' {
+				backslash = true
+			} else {
+				backslash = false
+			}
+		}
+	}
+	if !lastSpace {
+		cc = append(cc, s[start:])
+	}
+	return cc
+}
+
+func goEnv(t *testing.T, key string) string {
+	out, err := exec.Command("go", "env", key).CombinedOutput()
+	if err != nil {
+		t.Logf("go env %s\n", key)
+		t.Logf("%s", out)
+		t.Fatal(err)
+	}
+	return strings.TrimSpace(string(out))
+}
diff --git a/misc/cgo/test/callback.go b/misc/cgo/test/callback.go
index e749650293..814888e3ac 100644
--- a/misc/cgo/test/callback.go
+++ b/misc/cgo/test/callback.go
@@ -181,7 +181,7 @@ func testCallbackCallers(t *testing.T) {
 	name := []string{
 		"runtime.cgocallbackg1",
 		"runtime.cgocallbackg",
-		"runtime.cgocallback_gofunc",
+		"runtime.cgocallback",
 		"runtime.asmcgocall",
 		"runtime.cgocall",
 		"test._Cfunc_callback",
diff --git a/misc/cgo/test/cgo_linux_test.go b/misc/cgo/test/cgo_linux_test.go
index 7b56e11a27..a9746b552e 100644
--- a/misc/cgo/test/cgo_linux_test.go
+++ b/misc/cgo/test/cgo_linux_test.go
@@ -15,5 +15,6 @@ func TestSetgid(t *testing.T) {
 	}
 	testSetgid(t)
 }
+func Test1435(t *testing.T)    { test1435(t) }
 func Test6997(t *testing.T)    { test6997(t) }
 func TestBuildID(t *testing.T) { testBuildID(t) }
diff --git a/misc/cgo/test/cgo_test.go b/misc/cgo/test/cgo_test.go
index b745a4417f..f7a76d047b 100644
--- a/misc/cgo/test/cgo_test.go
+++ b/misc/cgo/test/cgo_test.go
@@ -76,6 +76,8 @@ func TestCheckConst(t *testing.T)            { testCheckConst(t) }
 func TestConst(t *testing.T)                 { testConst(t) }
 func TestCthread(t *testing.T)               { testCthread(t) }
 func TestEnum(t *testing.T)                  { testEnum(t) }
+func TestNamedEnum(t *testing.T)             { testNamedEnum(t) }
+func TestCastToEnum(t *testing.T)            { testCastToEnum(t) }
 func TestErrno(t *testing.T)                 { testErrno(t) }
 func TestFpVar(t *testing.T)                 { testFpVar(t) }
 func TestHelpers(t *testing.T)               { testHelpers(t) }
diff --git a/misc/cgo/test/issue1435.go b/misc/cgo/test/issue1435.go
new file mode 100644
index 0000000000..a1c7cacde7
--- /dev/null
+++ b/misc/cgo/test/issue1435.go
@@ -0,0 +1,184 @@
+// Copyright 2019 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.
+
+// +build linux,cgo
+
+package cgotest
+
+import (
+	"fmt"
+	"io/ioutil"
+	"strings"
+	"syscall"
+	"testing"
+)
+
+// #include <stdio.h>
+// #include <stdlib.h>
+// #include <pthread.h>
+// #include <unistd.h>
+// #include <sys/types.h>
+//
+// pthread_t *t = NULL;
+// pthread_mutex_t mu;
+// int nts = 0;
+// int all_done = 0;
+//
+// static void *aFn(void *vargp) {
+//   int done = 0;
+//   while (!done) {
+//     usleep(100);
+//     pthread_mutex_lock(&mu);
+//     done = all_done;
+//     pthread_mutex_unlock(&mu);
+//   }
+//   return NULL;
+// }
+//
+// void trial(int argc) {
+//   int i;
+//   nts = argc;
+//   t = calloc(nts, sizeof(pthread_t));
+//   pthread_mutex_init(&mu, NULL);
+//   for (i = 0; i < nts; i++) {
+//     pthread_create(&t[i], NULL, aFn, NULL);
+//   }
+// }
+//
+// void cleanup(void) {
+//   int i;
+//   pthread_mutex_lock(&mu);
+//   all_done = 1;
+//   pthread_mutex_unlock(&mu);
+//   for (i = 0; i < nts; i++) {
+//     pthread_join(t[i], NULL);
+//   }
+//   pthread_mutex_destroy(&mu);
+//   free(t);
+// }
+import "C"
+
+// compareStatus is used to confirm the contents of the thread
+// specific status files match expectations.
+func compareStatus(filter, expect string) error {
+	expected := filter + expect
+	pid := syscall.Getpid()
+	fs, err := ioutil.ReadDir(fmt.Sprintf("/proc/%d/task", pid))
+	if err != nil {
+		return fmt.Errorf("unable to find %d tasks: %v", pid, err)
+	}
+	expectedProc := fmt.Sprintf("Pid:\t%d", pid)
+	foundAThread := false
+	for _, f := range fs {
+		tf := fmt.Sprintf("/proc/%s/status", f.Name())
+		d, err := ioutil.ReadFile(tf)
+		if err != nil {
+			// There are a surprising number of ways this
+			// can error out on linux.  We've seen all of
+			// the following, so treat any error here as
+			// equivalent to the "process is gone":
+			//    os.IsNotExist(err),
+			//    "... : no such process",
+			//    "... : bad file descriptor.
+			continue
+		}
+		lines := strings.Split(string(d), "\n")
+		for _, line := range lines {
+			// Different kernel vintages pad differently.
+			line = strings.TrimSpace(line)
+			if strings.HasPrefix(line, "Pid:\t") {
+				// On loaded systems, it is possible
+				// for a TID to be reused really
+				// quickly. As such, we need to
+				// validate that the thread status
+				// info we just read is a task of the
+				// same process PID as we are
+				// currently running, and not a
+				// recently terminated thread
+				// resurfaced in a different process.
+				if line != expectedProc {
+					break
+				}
+				// Fall through in the unlikely case
+				// that filter at some point is
+				// "Pid:\t".
+			}
+			if strings.HasPrefix(line, filter) {
+				if line != expected {
+					return fmt.Errorf("%q got:%q want:%q (bad) [pid=%d file:'%s' %v]\n", tf, line, expected, pid, string(d), expectedProc)
+				}
+				foundAThread = true
+				break
+			}
+		}
+	}
+	if !foundAThread {
+		return fmt.Errorf("found no thread /proc/<TID>/status files for process %q", expectedProc)
+	}
+	return nil
+}
+
+// test1435 test 9 glibc implemented setuid/gid syscall functions are
+// mapped.  This test is a slightly more expansive test than that of
+// src/syscall/syscall_linux_test.go:TestSetuidEtc() insofar as it
+// launches concurrent threads from C code via CGo and validates that
+// they are subject to the system calls being tested. For the actual
+// Go functionality being tested here, the syscall_linux_test version
+// is considered authoritative, but non-trivial improvements to that
+// should be mirrored here.
+func test1435(t *testing.T) {
+	if syscall.Getuid() != 0 {
+		t.Skip("skipping root only test")
+	}
+
+	// Launch some threads in C.
+	const cts = 5
+	C.trial(cts)
+	defer C.cleanup()
+
+	vs := []struct {
+		call           string
+		fn             func() error
+		filter, expect string
+	}{
+		{call: "Setegid(1)", fn: func() error { return syscall.Setegid(1) }, filter: "Gid:", expect: "\t0\t1\t0\t1"},
+		{call: "Setegid(0)", fn: func() error { return syscall.Setegid(0) }, filter: "Gid:", expect: "\t0\t0\t0\t0"},
+
+		{call: "Seteuid(1)", fn: func() error { return syscall.Seteuid(1) }, filter: "Uid:", expect: "\t0\t1\t0\t1"},
+		{call: "Setuid(0)", fn: func() error { return syscall.Setuid(0) }, filter: "Uid:", expect: "\t0\t0\t0\t0"},
+
+		{call: "Setgid(1)", fn: func() error { return syscall.Setgid(1) }, filter: "Gid:", expect: "\t1\t1\t1\t1"},
+		{call: "Setgid(0)", fn: func() error { return syscall.Setgid(0) }, filter: "Gid:", expect: "\t0\t0\t0\t0"},
+
+		{call: "Setgroups([]int{0,1,2,3})", fn: func() error { return syscall.Setgroups([]int{0, 1, 2, 3}) }, filter: "Groups:", expect: "\t0 1 2 3"},
+		{call: "Setgroups(nil)", fn: func() error { return syscall.Setgroups(nil) }, filter: "Groups:", expect: ""},
+		{call: "Setgroups([]int{0})", fn: func() error { return syscall.Setgroups([]int{0}) }, filter: "Groups:", expect: "\t0"},
+
+		{call: "Setregid(101,0)", fn: func() error { return syscall.Setregid(101, 0) }, filter: "Gid:", expect: "\t101\t0\t0\t0"},
+		{call: "Setregid(0,102)", fn: func() error { return syscall.Setregid(0, 102) }, filter: "Gid:", expect: "\t0\t102\t102\t102"},
+		{call: "Setregid(0,0)", fn: func() error { return syscall.Setregid(0, 0) }, filter: "Gid:", expect: "\t0\t0\t0\t0"},
+
+		{call: "Setreuid(1,0)", fn: func() error { return syscall.Setreuid(1, 0) }, filter: "Uid:", expect: "\t1\t0\t0\t0"},
+		{call: "Setreuid(0,2)", fn: func() error { return syscall.Setreuid(0, 2) }, filter: "Uid:", expect: "\t0\t2\t2\t2"},
+		{call: "Setreuid(0,0)", fn: func() error { return syscall.Setreuid(0, 0) }, filter: "Uid:", expect: "\t0\t0\t0\t0"},
+
+		{call: "Setresgid(101,0,102)", fn: func() error { return syscall.Setresgid(101, 0, 102) }, filter: "Gid:", expect: "\t101\t0\t102\t0"},
+		{call: "Setresgid(0,102,101)", fn: func() error { return syscall.Setresgid(0, 102, 101) }, filter: "Gid:", expect: "\t0\t102\t101\t102"},
+		{call: "Setresgid(0,0,0)", fn: func() error { return syscall.Setresgid(0, 0, 0) }, filter: "Gid:", expect: "\t0\t0\t0\t0"},
+
+		{call: "Setresuid(1,0,2)", fn: func() error { return syscall.Setresuid(1, 0, 2) }, filter: "Uid:", expect: "\t1\t0\t2\t0"},
+		{call: "Setresuid(0,2,1)", fn: func() error { return syscall.Setresuid(0, 2, 1) }, filter: "Uid:", expect: "\t0\t2\t1\t2"},
+		{call: "Setresuid(0,0,0)", fn: func() error { return syscall.Setresuid(0, 0, 0) }, filter: "Uid:", expect: "\t0\t0\t0\t0"},
+	}
+
+	for i, v := range vs {
+		if err := v.fn(); err != nil {
+			t.Errorf("[%d] %q failed: %v", i, v.call, err)
+			continue
+		}
+		if err := compareStatus(v.filter, v.expect); err != nil {
+			t.Errorf("[%d] %q comparison: %v", i, v.call, err)
+		}
+	}
+}
diff --git a/misc/cgo/test/issue18146.go b/misc/cgo/test/issue18146.go
index 196d98f507..f92d6c7f93 100644
--- a/misc/cgo/test/issue18146.go
+++ b/misc/cgo/test/issue18146.go
@@ -24,7 +24,7 @@ func test18146(t *testing.T) {
 		t.Skip("skipping in short mode")
 	}
 
-	if runtime.GOOS == "darwin" {
+	if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
 		t.Skipf("skipping flaky test on %s; see golang.org/issue/18202", runtime.GOOS)
 	}
 
diff --git a/misc/cgo/test/issue4029.c b/misc/cgo/test/issue4029.c
index 30646ade02..e79c5a709c 100644
--- a/misc/cgo/test/issue4029.c
+++ b/misc/cgo/test/issue4029.c
@@ -3,6 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // +build !windows,!static
+// +build !darwin !internal_pie,!arm64
 
 #include <stdint.h>
 #include <dlfcn.h>
diff --git a/misc/cgo/test/issue4029.go b/misc/cgo/test/issue4029.go
index 1bf029d760..b2d131833a 100644
--- a/misc/cgo/test/issue4029.go
+++ b/misc/cgo/test/issue4029.go
@@ -3,6 +3,11 @@
 // license that can be found in the LICENSE file.
 
 // +build !windows,!static
+// +build !darwin !internal_pie,!arm64
+
+// Excluded in darwin internal linking PIE mode, as dynamic export is not
+// supported.
+// Excluded in internal linking mode on darwin/arm64, as it is always PIE.
 
 package cgotest
 
diff --git a/misc/cgo/test/issue4029w.go b/misc/cgo/test/issue4029w.go
index eee33f7010..b969bdd0fe 100644
--- a/misc/cgo/test/issue4029w.go
+++ b/misc/cgo/test/issue4029w.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build windows static
+// +build windows static darwin,internal_pie darwin,arm64
 
 package cgotest
 
diff --git a/misc/cgo/test/issue42495.go b/misc/cgo/test/issue42495.go
new file mode 100644
index 0000000000..509a67d9a3
--- /dev/null
+++ b/misc/cgo/test/issue42495.go
@@ -0,0 +1,15 @@
+// Copyright 2020 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 cgotest
+
+// typedef struct { } T42495A;
+// typedef struct { int x[0]; } T42495B;
+import "C"
+
+//export Issue42495A
+func Issue42495A(C.T42495A) {}
+
+//export Issue42495B
+func Issue42495B(C.T42495B) {}
diff --git a/misc/cgo/test/pkg_test.go b/misc/cgo/test/pkg_test.go
index 26c50ad883..a28ad4ea74 100644
--- a/misc/cgo/test/pkg_test.go
+++ b/misc/cgo/test/pkg_test.go
@@ -30,7 +30,7 @@ func TestCrossPackageTests(t *testing.T) {
 	switch runtime.GOOS {
 	case "android":
 		t.Skip("Can't exec cmd/go subprocess on Android.")
-	case "darwin":
+	case "darwin", "ios":
 		switch runtime.GOARCH {
 		case "arm64":
 			t.Skip("Can't exec cmd/go subprocess on iOS.")
diff --git a/misc/cgo/test/sigaltstack.go b/misc/cgo/test/sigaltstack.go
index 8dfa1cb5ad..034cc4b371 100644
--- a/misc/cgo/test/sigaltstack.go
+++ b/misc/cgo/test/sigaltstack.go
@@ -62,7 +62,7 @@ import (
 
 func testSigaltstack(t *testing.T) {
 	switch {
-	case runtime.GOOS == "solaris", runtime.GOOS == "illumos", runtime.GOOS == "darwin" && runtime.GOARCH == "arm64":
+	case runtime.GOOS == "solaris", runtime.GOOS == "illumos", runtime.GOOS == "ios" && runtime.GOARCH == "arm64":
 		t.Skipf("switching signal stack not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
 	}
 
diff --git a/misc/cgo/test/test.go b/misc/cgo/test/test.go
index 05fa52b381..65823b1ca0 100644
--- a/misc/cgo/test/test.go
+++ b/misc/cgo/test/test.go
@@ -1000,6 +1000,32 @@ func testEnum(t *testing.T) {
 	}
 }
 
+func testNamedEnum(t *testing.T) {
+	e := new(C.enum_E)
+
+	*e = C.Enum1
+	if *e != 1 {
+		t.Error("bad enum", C.Enum1)
+	}
+
+	*e = C.Enum2
+	if *e != 2 {
+		t.Error("bad enum", C.Enum2)
+	}
+}
+
+func testCastToEnum(t *testing.T) {
+	e := C.enum_E(C.Enum1)
+	if e != 1 {
+		t.Error("bad enum", C.Enum1)
+	}
+
+	e = C.enum_E(C.Enum2)
+	if e != 2 {
+		t.Error("bad enum", C.Enum2)
+	}
+}
+
 func testAtol(t *testing.T) {
 	l := Atol("123")
 	if l != 123 {
@@ -1776,7 +1802,7 @@ func test14838(t *testing.T) {
 var sink C.int
 
 func test17065(t *testing.T) {
-	if runtime.GOOS == "darwin" {
+	if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
 		t.Skip("broken on darwin; issue 17065")
 	}
 	for i := range C.ii {
diff --git a/misc/cgo/test/testdata/issue41761.go b/misc/cgo/test/testdata/issue41761.go
new file mode 100644
index 0000000000..919c749251
--- /dev/null
+++ b/misc/cgo/test/testdata/issue41761.go
@@ -0,0 +1,20 @@
+// Copyright 2020 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 cgotest
+
+/*
+   typedef struct S S;
+*/
+import "C"
+
+import (
+	"cgotest/issue41761a"
+	"testing"
+)
+
+func test41761(t *testing.T) {
+	var x issue41761a.T
+	_ = (*C.struct_S)(x.X)
+}
diff --git a/misc/cgo/test/testdata/issue41761a/a.go b/misc/cgo/test/testdata/issue41761a/a.go
new file mode 100644
index 0000000000..ca5c18191e
--- /dev/null
+++ b/misc/cgo/test/testdata/issue41761a/a.go
@@ -0,0 +1,14 @@
+// Copyright 2020 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 issue41761a
+
+/*
+   typedef struct S S;
+*/
+import "C"
+
+type T struct {
+	X *C.S
+}
diff --git a/misc/cgo/test/testdata/issue9400/asm_riscv64.s b/misc/cgo/test/testdata/issue9400/asm_riscv64.s
new file mode 100644
index 0000000000..20fcc0066d
--- /dev/null
+++ b/misc/cgo/test/testdata/issue9400/asm_riscv64.s
@@ -0,0 +1,31 @@
+// Copyright 2020 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.
+
+// +build riscv64
+// +build !gccgo
+
+#include "textflag.h"
+
+TEXT ·RewindAndSetgid(SB),NOSPLIT|NOFRAME,$0-0
+	// Rewind stack pointer so anything that happens on the stack
+	// will clobber the test pattern created by the caller
+	ADD	$(1024*8), X2
+
+	// Ask signaller to setgid
+	MOV	$1, X5
+	FENCE
+	MOVW	X5, ·Baton(SB)
+	FENCE
+
+	// Wait for setgid completion
+loop:
+	FENCE
+	MOVW	·Baton(SB), X5
+	OR	X6, X6, X6	// hint that we're in a spin loop
+	BNE	ZERO, X5, loop
+	FENCE
+
+	// Restore stack
+	ADD	$(-1024*8), X2
+	RET
diff --git a/misc/cgo/test/testx.go b/misc/cgo/test/testx.go
index 7fbc5c64b3..2b2e69ec00 100644
--- a/misc/cgo/test/testx.go
+++ b/misc/cgo/test/testx.go
@@ -164,7 +164,7 @@ func Add(x int) {
 }
 
 func testCthread(t *testing.T) {
-	if runtime.GOOS == "darwin" && runtime.GOARCH == "arm64" {
+	if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && runtime.GOARCH == "arm64" {
 		t.Skip("the iOS exec wrapper is unable to properly handle the panic from Add")
 	}
 	sum.i = 0
diff --git a/misc/cgo/testcarchive/carchive_test.go b/misc/cgo/testcarchive/carchive_test.go
index b4a046c4bc..6ed25d8948 100644
--- a/misc/cgo/testcarchive/carchive_test.go
+++ b/misc/cgo/testcarchive/carchive_test.go
@@ -118,9 +118,9 @@ func testMain(m *testing.M) int {
 		cc = append(cc, s[start:])
 	}
 
-	if GOOS == "darwin" {
+	if GOOS == "darwin" || GOOS == "ios" {
 		// For Darwin/ARM.
-		// TODO(crawshaw): can we do better?
+		// TODO: do we still need this?
 		cc = append(cc, []string{"-framework", "CoreFoundation", "-framework", "Foundation"}...)
 	}
 	if GOOS == "aix" {
@@ -133,7 +133,7 @@ func testMain(m *testing.M) int {
 		libbase = "gccgo_" + libgodir + "_fPIC"
 	} else {
 		switch GOOS {
-		case "darwin":
+		case "darwin", "ios":
 			if GOARCH == "arm64" {
 				libbase += "_shared"
 			}
@@ -303,7 +303,7 @@ func TestInstall(t *testing.T) {
 
 func TestEarlySignalHandler(t *testing.T) {
 	switch GOOS {
-	case "darwin":
+	case "darwin", "ios":
 		switch GOARCH {
 		case "arm64":
 			t.Skipf("skipping on %s/%s; see https://golang.org/issue/13701", GOOS, GOARCH)
@@ -384,7 +384,7 @@ func TestSignalForwarding(t *testing.T) {
 	expectSignal(t, err, syscall.SIGSEGV)
 
 	// SIGPIPE is never forwarded on darwin. See golang.org/issue/33384.
-	if runtime.GOOS != "darwin" {
+	if runtime.GOOS != "darwin" && runtime.GOOS != "ios" {
 		// Test SIGPIPE forwarding
 		cmd = exec.Command(bin[0], append(bin[1:], "3")...)
 
@@ -485,7 +485,7 @@ func TestSignalForwardingExternal(t *testing.T) {
 // doesn't work on this platform.
 func checkSignalForwardingTest(t *testing.T) {
 	switch GOOS {
-	case "darwin":
+	case "darwin", "ios":
 		switch GOARCH {
 		case "arm64":
 			t.Skipf("skipping on %s/%s; see https://golang.org/issue/13701", GOOS, GOARCH)
@@ -603,7 +603,7 @@ func TestExtar(t *testing.T) {
 	if runtime.Compiler == "gccgo" {
 		t.Skip("skipping -extar test when using gccgo")
 	}
-	if runtime.GOOS == "darwin" && runtime.GOARCH == "arm64" {
+	if runtime.GOOS == "ios" {
 		t.Skip("shell scripts are not executable on iOS hosts")
 	}
 
@@ -645,7 +645,7 @@ func TestExtar(t *testing.T) {
 
 func TestPIE(t *testing.T) {
 	switch GOOS {
-	case "windows", "darwin", "plan9":
+	case "windows", "darwin", "ios", "plan9":
 		t.Skipf("skipping PIE test on %s", GOOS)
 	}
 
@@ -738,7 +738,7 @@ func TestSIGPROF(t *testing.T) {
 	switch GOOS {
 	case "windows", "plan9":
 		t.Skipf("skipping SIGPROF test on %s", GOOS)
-	case "darwin":
+	case "darwin", "ios":
 		t.Skipf("skipping SIGPROF test on %s; see https://golang.org/issue/19320", GOOS)
 	}
 
@@ -841,7 +841,7 @@ func TestCompileWithoutShared(t *testing.T) {
 	expectSignal(t, err, syscall.SIGSEGV)
 
 	// SIGPIPE is never forwarded on darwin. See golang.org/issue/33384.
-	if runtime.GOOS != "darwin" {
+	if runtime.GOOS != "darwin" && runtime.GOOS != "ios" {
 		binArgs := append(cmdToRun(exe), "3")
 		t.Log(binArgs)
 		out, err = exec.Command(binArgs[0], binArgs[1:]...).CombinedOutput()
diff --git a/misc/cgo/testcshared/cshared_test.go b/misc/cgo/testcshared/cshared_test.go
index bd4d341820..3a4886cf30 100644
--- a/misc/cgo/testcshared/cshared_test.go
+++ b/misc/cgo/testcshared/cshared_test.go
@@ -7,6 +7,8 @@ package cshared_test
 import (
 	"bytes"
 	"debug/elf"
+	"debug/pe"
+	"encoding/binary"
 	"flag"
 	"fmt"
 	"io/ioutil"
@@ -98,7 +100,7 @@ func testMain(m *testing.M) int {
 	}
 
 	switch GOOS {
-	case "darwin":
+	case "darwin", "ios":
 		// For Darwin/ARM.
 		// TODO(crawshaw): can we do better?
 		cc = append(cc, []string{"-framework", "CoreFoundation", "-framework", "Foundation"}...)
@@ -107,7 +109,7 @@ func testMain(m *testing.M) int {
 	}
 	libgodir := GOOS + "_" + GOARCH
 	switch GOOS {
-	case "darwin":
+	case "darwin", "ios":
 		if GOARCH == "arm64" {
 			libgodir += "_shared"
 		}
@@ -355,6 +357,101 @@ func TestExportedSymbols(t *testing.T) {
 	}
 }
 
+func checkNumberOfExportedFunctionsWindows(t *testing.T, exportAllSymbols bool) {
+	const prog = `
+package main
+
+import "C"
+
+//export GoFunc
+func GoFunc() {
+	println(42)
+}
+
+//export GoFunc2
+func GoFunc2() {
+	println(24)
+}
+
+func main() {
+}
+`
+
+	tmpdir := t.TempDir()
+
+	srcfile := filepath.Join(tmpdir, "test.go")
+	objfile := filepath.Join(tmpdir, "test.dll")
+	if err := ioutil.WriteFile(srcfile, []byte(prog), 0666); err != nil {
+		t.Fatal(err)
+	}
+	argv := []string{"build", "-buildmode=c-shared"}
+	if exportAllSymbols {
+		argv = append(argv, "-ldflags", "-extldflags=-Wl,--export-all-symbols")
+	}
+	argv = append(argv, "-o", objfile, srcfile)
+	out, err := exec.Command("go", argv...).CombinedOutput()
+	if err != nil {
+		t.Fatalf("build failure: %s\n%s\n", err, string(out))
+	}
+
+	f, err := pe.Open(objfile)
+	if err != nil {
+		t.Fatalf("pe.Open failed: %v", err)
+	}
+	defer f.Close()
+	section := f.Section(".edata")
+	if section == nil {
+		t.Fatalf(".edata section is not present")
+	}
+
+	// TODO: deduplicate this struct from cmd/link/internal/ld/pe.go
+	type IMAGE_EXPORT_DIRECTORY struct {
+		_                 [2]uint32
+		_                 [2]uint16
+		_                 [2]uint32
+		NumberOfFunctions uint32
+		NumberOfNames     uint32
+		_                 [3]uint32
+	}
+	var e IMAGE_EXPORT_DIRECTORY
+	if err := binary.Read(section.Open(), binary.LittleEndian, &e); err != nil {
+		t.Fatalf("binary.Read failed: %v", err)
+	}
+
+	// Only the two exported functions and _cgo_dummy_export should be exported
+	expectedNumber := uint32(3)
+
+	if exportAllSymbols {
+		if e.NumberOfFunctions <= expectedNumber {
+			t.Fatalf("missing exported functions: %v", e.NumberOfFunctions)
+		}
+		if e.NumberOfNames <= expectedNumber {
+			t.Fatalf("missing exported names: %v", e.NumberOfNames)
+		}
+	} else {
+		if e.NumberOfFunctions != expectedNumber {
+			t.Fatalf("got %d exported functions; want %d", e.NumberOfFunctions, expectedNumber)
+		}
+		if e.NumberOfNames != expectedNumber {
+			t.Fatalf("got %d exported names; want %d", e.NumberOfNames, expectedNumber)
+		}
+	}
+}
+
+func TestNumberOfExportedFunctions(t *testing.T) {
+	if GOOS != "windows" {
+		t.Skip("skipping windows only test")
+	}
+	t.Parallel()
+
+	t.Run("OnlyExported", func(t *testing.T) {
+		checkNumberOfExportedFunctionsWindows(t, false)
+	})
+	t.Run("All", func(t *testing.T) {
+		checkNumberOfExportedFunctionsWindows(t, true)
+	})
+}
+
 // test1: shared library can be dynamically loaded and exported symbols are accessible.
 func TestExportedSymbolsWithDynamicLoad(t *testing.T) {
 	t.Parallel()
@@ -407,7 +504,7 @@ func TestUnexportedSymbols(t *testing.T) {
 	adbPush(t, libname)
 
 	linkFlags := "-Wl,--no-as-needed"
-	if GOOS == "darwin" {
+	if GOOS == "darwin" || GOOS == "ios" {
 		linkFlags = ""
 	}
 
@@ -636,7 +733,7 @@ func copyFile(t *testing.T, dst, src string) {
 
 func TestGo2C2Go(t *testing.T) {
 	switch GOOS {
-	case "darwin":
+	case "darwin", "ios":
 		// Darwin shared libraries don't support the multiple
 		// copies of the runtime package implied by this test.
 		t.Skip("linking c-shared into Go programs not supported on Darwin; issue 29061")
diff --git a/misc/cgo/testgodefs/testdata/bitfields.go b/misc/cgo/testgodefs/testdata/bitfields.go
new file mode 100644
index 0000000000..6a9724dcd1
--- /dev/null
+++ b/misc/cgo/testgodefs/testdata/bitfields.go
@@ -0,0 +1,31 @@
+// Copyright 2020 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.
+//
+// +build ignore
+
+package main
+
+// This file tests that we don't generate an incorrect field location
+// for a bitfield that appears aligned.
+
+/*
+struct bitfields {
+    unsigned int B1     :  5;
+    unsigned int B2     :  1;
+    unsigned int B3     :  1;
+    unsigned int B4     :  1;
+    unsigned int Short1 : 16; // misaligned on 8 bit boundary
+    unsigned int B5     :  1;
+    unsigned int B6     :  1;
+    unsigned int B7     :  1;
+    unsigned int B8     :  1;
+    unsigned int B9     :  1;
+    unsigned int B10    :  3;
+    unsigned int Short2 : 16; // alignment is OK
+    unsigned int Short3 : 16; // alignment is OK
+};
+*/
+import "C"
+
+type bitfields C.struct_bitfields
diff --git a/misc/cgo/testgodefs/testdata/main.go b/misc/cgo/testgodefs/testdata/main.go
index 2e1ad3376a..4a3f6a701c 100644
--- a/misc/cgo/testgodefs/testdata/main.go
+++ b/misc/cgo/testgodefs/testdata/main.go
@@ -4,6 +4,12 @@
 
 package main
 
+import (
+	"fmt"
+	"os"
+	"reflect"
+)
+
 // Test that the struct field in anonunion.go was promoted.
 var v1 T
 var v2 = v1.L
@@ -23,4 +29,26 @@ var v7 = S{}
 var _ = issue38649{X: 0}
 
 func main() {
+	pass := true
+
+	// The Go translation of bitfields should not have any of the
+	// bitfield types. The order in which bitfields are laid out
+	// in memory is implementation defined, so we can't easily
+	// know how a bitfield should correspond to a Go type, even if
+	// it appears to be aligned correctly.
+	bitfieldType := reflect.TypeOf(bitfields{})
+	check := func(name string) {
+		_, ok := bitfieldType.FieldByName(name)
+		if ok {
+			fmt.Fprintf(os.Stderr, "found unexpected bitfields field %s\n", name)
+			pass = false
+		}
+	}
+	check("Short1")
+	check("Short2")
+	check("Short3")
+
+	if !pass {
+		os.Exit(1)
+	}
 }
diff --git a/misc/cgo/testgodefs/testgodefs_test.go b/misc/cgo/testgodefs/testgodefs_test.go
index e4085f9ca8..4c2312c1c8 100644
--- a/misc/cgo/testgodefs/testgodefs_test.go
+++ b/misc/cgo/testgodefs/testgodefs_test.go
@@ -19,6 +19,7 @@ import (
 // import "C" block.  Add more tests here.
 var filePrefixes = []string{
 	"anonunion",
+	"bitfields",
 	"issue8478",
 	"fieldtypedef",
 	"issue37479",
diff --git a/misc/cgo/testplugin/plugin_test.go b/misc/cgo/testplugin/plugin_test.go
index 2875271c03..9055dbda04 100644
--- a/misc/cgo/testplugin/plugin_test.go
+++ b/misc/cgo/testplugin/plugin_test.go
@@ -196,3 +196,17 @@ func TestIssue25756(t *testing.T) {
 		})
 	}
 }
+
+func TestMethod(t *testing.T) {
+	// Exported symbol's method must be live.
+	goCmd(t, "build", "-buildmode=plugin", "-o", "plugin.so", "./method/plugin.go")
+	goCmd(t, "build", "-o", "method.exe", "./method/main.go")
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	cmd := exec.CommandContext(ctx, "./method.exe")
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+}
diff --git a/misc/cgo/testplugin/testdata/method/main.go b/misc/cgo/testplugin/testdata/method/main.go
new file mode 100644
index 0000000000..5e9189b450
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/method/main.go
@@ -0,0 +1,26 @@
+// Copyright 2020 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.
+
+// Issue 42579: methods of symbols exported from plugin must be live.
+
+package main
+
+import (
+	"plugin"
+	"reflect"
+)
+
+func main() {
+	p, err := plugin.Open("plugin.so")
+	if err != nil {
+		panic(err)
+	}
+
+	x, err := p.Lookup("X")
+	if err != nil {
+		panic(err)
+	}
+
+	reflect.ValueOf(x).Elem().MethodByName("M").Call(nil)
+}
diff --git a/misc/cgo/testplugin/testdata/method/plugin.go b/misc/cgo/testplugin/testdata/method/plugin.go
new file mode 100644
index 0000000000..240edd3bc4
--- /dev/null
+++ b/misc/cgo/testplugin/testdata/method/plugin.go
@@ -0,0 +1,13 @@
+// Copyright 2020 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 main
+
+func main() {}
+
+type T int
+
+func (T) M() { println("M") }
+
+var X T
diff --git a/misc/cgo/testsanitizers/msan_test.go b/misc/cgo/testsanitizers/msan_test.go
index 88b90d3d70..5e2f9759ba 100644
--- a/misc/cgo/testsanitizers/msan_test.go
+++ b/misc/cgo/testsanitizers/msan_test.go
@@ -28,6 +28,7 @@ func TestMSAN(t *testing.T) {
 		{src: "msan4.go"},
 		{src: "msan5.go"},
 		{src: "msan6.go"},
+		{src: "msan7.go"},
 		{src: "msan_fail.go", wantErr: true},
 	}
 	for _, tc := range cases {
diff --git a/misc/cgo/testsanitizers/testdata/msan7.go b/misc/cgo/testsanitizers/testdata/msan7.go
new file mode 100644
index 0000000000..2f29fd21b2
--- /dev/null
+++ b/misc/cgo/testsanitizers/testdata/msan7.go
@@ -0,0 +1,38 @@
+// Copyright 2020 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 main
+
+// Test passing C struct to exported Go function.
+
+/*
+#include <stdint.h>
+#include <stdlib.h>
+
+// T is a C struct with alignment padding after b.
+// The padding bytes are not considered initialized by MSAN.
+// It is big enough to be passed on stack in C ABI (and least
+// on AMD64).
+typedef struct { char b; uintptr_t x, y; } T;
+
+extern void F(T);
+
+// Use weak as a hack to permit defining a function even though we use export.
+void CF(int x) __attribute__ ((weak));
+void CF(int x) {
+	T *t = malloc(sizeof(T));
+	t->b = (char)x;
+	t->x = x;
+	t->y = x;
+	F(*t);
+}
+*/
+import "C"
+
+//export F
+func F(t C.T) { println(t.b, t.x, t.y) }
+
+func main() {
+	C.CF(C.int(0))
+}
diff --git a/misc/cgo/testso/so_test.go b/misc/cgo/testso/so_test.go
index bdd6bd8468..57f0fd34f7 100644
--- a/misc/cgo/testso/so_test.go
+++ b/misc/cgo/testso/so_test.go
@@ -21,7 +21,7 @@ func requireTestSOSupported(t *testing.T) {
 	t.Helper()
 	switch runtime.GOARCH {
 	case "arm64":
-		if runtime.GOOS == "darwin" {
+		if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
 			t.Skip("No exec facility on iOS.")
 		}
 	case "ppc64":
@@ -74,7 +74,7 @@ func TestSO(t *testing.T) {
 	ext := "so"
 	args := append(gogccflags, "-shared")
 	switch runtime.GOOS {
-	case "darwin":
+	case "darwin", "ios":
 		ext = "dylib"
 		args = append(args, "-undefined", "suppress", "-flat_namespace")
 	case "windows":
@@ -119,7 +119,7 @@ func TestSO(t *testing.T) {
 	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
 	if runtime.GOOS != "windows" {
 		s := "LD_LIBRARY_PATH"
-		if runtime.GOOS == "darwin" {
+		if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
 			s = "DYLD_LIBRARY_PATH"
 		}
 		cmd.Env = append(os.Environ(), s+"=.")
diff --git a/misc/cgo/testsovar/so_test.go b/misc/cgo/testsovar/so_test.go
index bdd6bd8468..57f0fd34f7 100644
--- a/misc/cgo/testsovar/so_test.go
+++ b/misc/cgo/testsovar/so_test.go
@@ -21,7 +21,7 @@ func requireTestSOSupported(t *testing.T) {
 	t.Helper()
 	switch runtime.GOARCH {
 	case "arm64":
-		if runtime.GOOS == "darwin" {
+		if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
 			t.Skip("No exec facility on iOS.")
 		}
 	case "ppc64":
@@ -74,7 +74,7 @@ func TestSO(t *testing.T) {
 	ext := "so"
 	args := append(gogccflags, "-shared")
 	switch runtime.GOOS {
-	case "darwin":
+	case "darwin", "ios":
 		ext = "dylib"
 		args = append(args, "-undefined", "suppress", "-flat_namespace")
 	case "windows":
@@ -119,7 +119,7 @@ func TestSO(t *testing.T) {
 	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
 	if runtime.GOOS != "windows" {
 		s := "LD_LIBRARY_PATH"
-		if runtime.GOOS == "darwin" {
+		if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
 			s = "DYLD_LIBRARY_PATH"
 		}
 		cmd.Env = append(os.Environ(), s+"=.")
diff --git a/misc/ios/README b/misc/ios/README
index d7df191414..433bcdfd8f 100644
--- a/misc/ios/README
+++ b/misc/ios/README
@@ -1,13 +1,20 @@
 Go on iOS
 =========
 
-For details on developing Go for iOS on macOS, see the documentation in the mobile
-subrepository:
+To run the standard library tests, run all.bash as usual, but with the compiler
+set to the clang wrapper that invokes clang for iOS. For example, this command runs
+ all.bash on the iOS emulator:
 
-    https://github.com/golang/mobile
+	GOOS=ios GOARCH=amd64 CGO_ENABLED=1 CC_FOR_TARGET=$(pwd)/../misc/ios/clangwrap.sh ./all.bash
 
-It is necessary to set up the environment before running tests or programs directly on a
-device.
+To use the go tool to run individual programs and tests, put $GOROOT/bin into PATH to ensure
+the go_ios_$GOARCH_exec wrapper is found. For example, to run the archive/tar tests:
+
+	export PATH=$GOROOT/bin:$PATH
+	GOOS=ios GOARCH=amd64 CGO_ENABLED=1 go test archive/tar
+
+The go_ios_exec wrapper uses GOARCH to select the emulator (amd64) or the device (arm64).
+However, further setup is required to run tests or programs directly on a device.
 
 First make sure you have a valid developer certificate and have setup your device properly
 to run apps signed by your developer certificate. Then install the libimobiledevice and
@@ -29,18 +36,10 @@ which will output something similar to
 	export GOIOS_TEAM_ID=ZZZZZZZZ
 
 If you have multiple devices connected, specify the device UDID with the GOIOS_DEVICE_ID
-variable. Use `idevice_id -l` to list all available UDIDs.
-
-Finally, to run the standard library tests, run all.bash as usual, but with the compiler
-set to the clang wrapper that invokes clang for iOS. For example,
+variable. Use `idevice_id -l` to list all available UDIDs. Then, setting GOARCH to arm64
+will select the device:
 
-	GOARCH=arm64 CGO_ENABLED=1 CC_FOR_TARGET=$(pwd)/../misc/ios/clangwrap.sh ./all.bash
-
-To use the go tool directly to run programs and tests, put $GOROOT/bin into PATH to ensure
-the go_darwin_$GOARCH_exec wrapper is found. For example, to run the archive/tar tests
-
-	export PATH=$GOROOT/bin:$PATH
-	GOARCH=arm64 CGO_ENABLED=1 go test archive/tar
+	GOOS=ios GOARCH=arm64 CGO_ENABLED=1 CC_FOR_TARGET=$(pwd)/../misc/ios/clangwrap.sh ./all.bash
 
 Note that the go_darwin_$GOARCH_exec wrapper uninstalls any existing app identified by
 the bundle id before installing a new app. If the uninstalled app is the last app by
diff --git a/misc/ios/clangwrap.sh b/misc/ios/clangwrap.sh
index 5fdbb6db4a..dca3fcc904 100755
--- a/misc/ios/clangwrap.sh
+++ b/misc/ios/clangwrap.sh
@@ -2,17 +2,19 @@
 # This uses the latest available iOS SDK, which is recommended.
 # To select a specific SDK, run 'xcodebuild -showsdks'
 # to see the available SDKs and replace iphoneos with one of them.
-SDK=iphoneos
-SDK_PATH=`xcrun --sdk $SDK --show-sdk-path`
-export IPHONEOS_DEPLOYMENT_TARGET=5.1
-# cmd/cgo doesn't support llvm-gcc-4.2, so we have to use clang.
-CLANG=`xcrun --sdk $SDK --find clang`
-
 if [ "$GOARCH" == "arm64" ]; then
+	SDK=iphoneos
+	PLATFORM=ios
 	CLANGARCH="arm64"
 else
-	echo "unknown GOARCH=$GOARCH" >&2
-	exit 1
+	SDK=iphonesimulator
+	PLATFORM=ios-simulator
+	CLANGARCH="x86_64"
 fi
 
-exec $CLANG -arch $CLANGARCH -isysroot $SDK_PATH -mios-version-min=10.0 "$@"
+SDK_PATH=`xcrun --sdk $SDK --show-sdk-path`
+export IPHONEOS_DEPLOYMENT_TARGET=5.1
+# cmd/cgo doesn't support llvm-gcc-4.2, so we have to use clang.
+CLANG=`xcrun --sdk $SDK --find clang`
+
+exec "$CLANG" -arch $CLANGARCH -isysroot "$SDK_PATH" -m${PLATFORM}-version-min=10.0 "$@"
diff --git a/misc/ios/detect.go b/misc/ios/detect.go
index 1d47e47c86..d32bcc3202 100644
--- a/misc/ios/detect.go
+++ b/misc/ios/detect.go
@@ -6,7 +6,7 @@
 
 // detect attempts to autodetect the correct
 // values of the environment variables
-// used by go_darwin_arm_exec.
+// used by go_ios_exec.
 // detect shells out to ideviceinfo, a third party program that can
 // be obtained by following the instructions at
 // https://github.com/libimobiledevice/libimobiledevice.
diff --git a/misc/ios/go_darwin_arm_exec.go b/misc/ios/go_ios_exec.go
index cdf4b07d0a..0acf1b259c 100644
--- a/misc/ios/go_darwin_arm_exec.go
+++ b/misc/ios/go_ios_exec.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// This program can be used as go_darwin_arm_exec by the Go tool.
+// This program can be used as go_ios_$GOARCH_exec by the Go tool.
 // It executes binaries on an iOS device using the XCode toolchain
 // and the ios-deploy program: https://github.com/phonegap/ios-deploy
 //
@@ -34,6 +34,7 @@ import (
 	"os/signal"
 	"path/filepath"
 	"runtime"
+	"strconv"
 	"strings"
 	"syscall"
 	"time"
@@ -58,34 +59,16 @@ var lock *os.File
 
 func main() {
 	log.SetFlags(0)
-	log.SetPrefix("go_darwin_arm_exec: ")
+	log.SetPrefix("go_ios_exec: ")
 	if debug {
 		log.Println(strings.Join(os.Args, " "))
 	}
 	if len(os.Args) < 2 {
-		log.Fatal("usage: go_darwin_arm_exec a.out")
+		log.Fatal("usage: go_ios_exec a.out")
 	}
 
-	// e.g. B393DDEB490947F5A463FD074299B6C0AXXXXXXX
-	devID = getenv("GOIOS_DEV_ID")
-
-	// e.g. Z8B3JBXXXX.org.golang.sample, Z8B3JBXXXX prefix is available at
-	// https://developer.apple.com/membercenter/index.action#accountSummary as Team ID.
-	appID = getenv("GOIOS_APP_ID")
-
-	// e.g. Z8B3JBXXXX, available at
-	// https://developer.apple.com/membercenter/index.action#accountSummary as Team ID.
-	teamID = getenv("GOIOS_TEAM_ID")
-
-	// Device IDs as listed with ios-deploy -c.
-	deviceID = os.Getenv("GOIOS_DEVICE_ID")
-
-	parts := strings.SplitN(appID, ".", 2)
 	// For compatibility with the old builders, use a fallback bundle ID
 	bundleID = "golang.gotest"
-	if len(parts) == 2 {
-		bundleID = parts[1]
-	}
 
 	exitCode, err := runMain()
 	if err != nil {
@@ -96,7 +79,7 @@ func main() {
 
 func runMain() (int, error) {
 	var err error
-	tmpdir, err = ioutil.TempDir("", "go_darwin_arm_exec_")
+	tmpdir, err = ioutil.TempDir("", "go_ios_exec_")
 	if err != nil {
 		return 1, err
 	}
@@ -117,7 +100,7 @@ func runMain() (int, error) {
 	//
 	// The lock file is never deleted, to avoid concurrent locks on distinct
 	// files with the same path.
-	lockName := filepath.Join(os.TempDir(), "go_darwin_arm_exec-"+deviceID+".lock")
+	lockName := filepath.Join(os.TempDir(), "go_ios_exec-"+deviceID+".lock")
 	lock, err = os.OpenFile(lockName, os.O_CREATE|os.O_RDONLY, 0666)
 	if err != nil {
 		return 1, err
@@ -126,16 +109,65 @@ func runMain() (int, error) {
 		return 1, err
 	}
 
-	if err := uninstall(bundleID); err != nil {
+	if goarch := os.Getenv("GOARCH"); goarch == "arm64" {
+		err = runOnDevice(appdir)
+	} else {
+		err = runOnSimulator(appdir)
+	}
+	if err != nil {
+		// If the lldb driver completed with an exit code, use that.
+		if err, ok := err.(*exec.ExitError); ok {
+			if ws, ok := err.Sys().(interface{ ExitStatus() int }); ok {
+				return ws.ExitStatus(), nil
+			}
+		}
 		return 1, err
 	}
+	return 0, nil
+}
+
+func runOnSimulator(appdir string) error {
+	if err := installSimulator(appdir); err != nil {
+		return err
+	}
 
-	if err := install(appdir); err != nil {
-		return 1, err
+	return runSimulator(appdir, bundleID, os.Args[2:])
+}
+
+func runOnDevice(appdir string) error {
+	// e.g. B393DDEB490947F5A463FD074299B6C0AXXXXXXX
+	devID = getenv("GOIOS_DEV_ID")
+
+	// e.g. Z8B3JBXXXX.org.golang.sample, Z8B3JBXXXX prefix is available at
+	// https://developer.apple.com/membercenter/index.action#accountSummary as Team ID.
+	appID = getenv("GOIOS_APP_ID")
+
+	// e.g. Z8B3JBXXXX, available at
+	// https://developer.apple.com/membercenter/index.action#accountSummary as Team ID.
+	teamID = getenv("GOIOS_TEAM_ID")
+
+	// Device IDs as listed with ios-deploy -c.
+	deviceID = os.Getenv("GOIOS_DEVICE_ID")
+
+	parts := strings.SplitN(appID, ".", 2)
+	if len(parts) == 2 {
+		bundleID = parts[1]
+	}
+
+	if err := signApp(appdir); err != nil {
+		return err
+	}
+
+	if err := uninstallDevice(bundleID); err != nil {
+		return err
+	}
+
+	if err := installDevice(appdir); err != nil {
+		return err
 	}
 
 	if err := mountDevImage(); err != nil {
-		return 1, err
+		return err
 	}
 
 	// Kill any hanging debug bridges that might take up port 3222.
@@ -143,20 +175,11 @@ func runMain() (int, error) {
 
 	closer, err := startDebugBridge()
 	if err != nil {
-		return 1, err
+		return err
 	}
 	defer closer()
 
-	if err := run(appdir, bundleID, os.Args[2:]); err != nil {
-		// If the lldb driver completed with an exit code, use that.
-		if err, ok := err.(*exec.ExitError); ok {
-			if ws, ok := err.Sys().(interface{ ExitStatus() int }); ok {
-				return ws.ExitStatus(), nil
-			}
-		}
-		return 1, err
-	}
-	return 0, nil
+	return runDevice(appdir, bundleID, os.Args[2:])
 }
 
 func getenv(envvar string) string {
@@ -191,7 +214,11 @@ func assembleApp(appdir, bin string) error {
 	if err := ioutil.WriteFile(filepath.Join(appdir, "ResourceRules.plist"), []byte(resourceRules), 0744); err != nil {
 		return err
 	}
+	return nil
+}
 
+func signApp(appdir string) error {
+	entitlementsPath := filepath.Join(tmpdir, "Entitlements.plist")
 	cmd := exec.Command(
 		"codesign",
 		"-f",
@@ -421,7 +448,20 @@ func parsePlistDict(dict []byte) (map[string]string, error) {
 	return values, nil
 }
 
-func uninstall(bundleID string) error {
+func installSimulator(appdir string) error {
+	cmd := exec.Command(
+		"xcrun", "simctl", "install",
+		"booted", // Install to the booted simulator.
+		appdir,
+	)
+	if out, err := cmd.CombinedOutput(); err != nil {
+		os.Stderr.Write(out)
+		return fmt.Errorf("xcrun simctl install booted %q: %v", appdir, err)
+	}
+	return nil
+}
+
+func uninstallDevice(bundleID string) error {
 	cmd := idevCmd(exec.Command(
 		"ideviceinstaller",
 		"-U", bundleID,
@@ -433,7 +473,7 @@ func uninstall(bundleID string) error {
 	return nil
 }
 
-func install(appdir string) error {
+func installDevice(appdir string) error {
 	attempt := 0
 	for {
 		cmd := idevCmd(exec.Command(
@@ -464,15 +504,28 @@ func idevCmd(cmd *exec.Cmd) *exec.Cmd {
 	return cmd
 }
 
-func run(appdir, bundleID string, args []string) error {
-	var env []string
-	for _, e := range os.Environ() {
-		// Don't override TMPDIR, HOME, GOCACHE on the device.
-		if strings.HasPrefix(e, "TMPDIR=") || strings.HasPrefix(e, "HOME=") || strings.HasPrefix(e, "GOCACHE=") {
-			continue
-		}
-		env = append(env, e)
+func runSimulator(appdir, bundleID string, args []string) error {
+	cmd := exec.Command(
+		"xcrun", "simctl", "launch",
+		"--wait-for-debugger",
+		"booted",
+		bundleID,
+	)
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		os.Stderr.Write(out)
+		return fmt.Errorf("xcrun simctl launch booted %q: %v", bundleID, err)
+	}
+	var processID int
+	var ignore string
+	if _, err := fmt.Sscanf(string(out), "%s %d", &ignore, &processID); err != nil {
+		return fmt.Errorf("runSimulator: couldn't find processID from `simctl launch`: %v (%q)", err, out)
 	}
+	_, err = runLLDB("ios-simulator", appdir, strconv.Itoa(processID), args)
+	return err
+}
+
+func runDevice(appdir, bundleID string, args []string) error {
 	attempt := 0
 	for {
 		// The device app path reported by the device might be stale, so retry
@@ -487,37 +540,10 @@ func run(appdir, bundleID string, args []string) error {
 			time.Sleep(5 * time.Second)
 			continue
 		}
-		lldb := exec.Command(
-			"python",
-			"-", // Read script from stdin.
-			appdir,
-			deviceapp,
-		)
-		lldb.Args = append(lldb.Args, args...)
-		lldb.Env = env
-		lldb.Stdin = strings.NewReader(lldbDriver)
-		lldb.Stdout = os.Stdout
-		var out bytes.Buffer
-		lldb.Stderr = io.MultiWriter(&out, os.Stderr)
-		err = lldb.Start()
-		if err == nil {
-			// Forward SIGQUIT to the lldb driver which in turn will forward
-			// to the running program.
-			sigs := make(chan os.Signal, 1)
-			signal.Notify(sigs, syscall.SIGQUIT)
-			proc := lldb.Process
-			go func() {
-				for sig := range sigs {
-					proc.Signal(sig)
-				}
-			}()
-			err = lldb.Wait()
-			signal.Stop(sigs)
-			close(sigs)
-		}
+		out, err := runLLDB("remote-ios", appdir, deviceapp, args)
 		// If the program was not started it can be retried without papering over
 		// real test failures.
-		started := bytes.HasPrefix(out.Bytes(), []byte("lldb: running program"))
+		started := bytes.HasPrefix(out, []byte("lldb: running program"))
 		if started || err == nil || attempt == 5 {
 			return err
 		}
@@ -528,6 +554,47 @@ func run(appdir, bundleID string, args []string) error {
 	}
 }
 
+func runLLDB(target, appdir, deviceapp string, args []string) ([]byte, error) {
+	var env []string
+	for _, e := range os.Environ() {
+		// Don't override TMPDIR, HOME, GOCACHE on the device.
+		if strings.HasPrefix(e, "TMPDIR=") || strings.HasPrefix(e, "HOME=") || strings.HasPrefix(e, "GOCACHE=") {
+			continue
+		}
+		env = append(env, e)
+	}
+	lldb := exec.Command(
+		"python",
+		"-", // Read script from stdin.
+		target,
+		appdir,
+		deviceapp,
+	)
+	lldb.Args = append(lldb.Args, args...)
+	lldb.Env = env
+	lldb.Stdin = strings.NewReader(lldbDriver)
+	lldb.Stdout = os.Stdout
+	var out bytes.Buffer
+	lldb.Stderr = io.MultiWriter(&out, os.Stderr)
+	err := lldb.Start()
+	if err == nil {
+		// Forward SIGQUIT to the lldb driver which in turn will forward
+		// to the running program.
+		sigs := make(chan os.Signal, 1)
+		signal.Notify(sigs, syscall.SIGQUIT)
+		proc := lldb.Process
+		go func() {
+			for sig := range sigs {
+				proc.Signal(sig)
+			}
+		}()
+		err = lldb.Wait()
+		signal.Stop(sigs)
+		close(sigs)
+	}
+	return out.Bytes(), err
+}
+
 func copyLocalDir(dst, src string) error {
 	if err := os.Mkdir(dst, 0755); err != nil {
 		return err
@@ -679,6 +746,7 @@ func infoPlist(pkgpath string) string {
 <key>CFBundleSupportedPlatforms</key><array><string>iPhoneOS</string></array>
 <key>CFBundleExecutable</key><string>gotest</string>
 <key>CFBundleVersion</key><string>1.0</string>
+<key>CFBundleShortVersionString</key><string>1.0</string>
 <key>CFBundleIdentifier</key><string>` + bundleID + `</string>
 <key>CFBundleResourceSpecification</key><string>ResourceRules.plist</string>
 <key>LSRequiresIPhoneOS</key><true/>
@@ -739,7 +807,7 @@ import sys
 import os
 import signal
 
-exe, device_exe, args = sys.argv[1], sys.argv[2], sys.argv[3:]
+platform, exe, device_exe_or_pid, args = sys.argv[1], sys.argv[2], sys.argv[3], sys.argv[4:]
 
 env = []
 for k, v in os.environ.items():
@@ -754,17 +822,21 @@ debugger.SetAsync(True)
 debugger.SkipLLDBInitFiles(True)
 
 err = lldb.SBError()
-target = debugger.CreateTarget(exe, None, 'remote-ios', True, err)
+target = debugger.CreateTarget(exe, None, platform, True, err)
 if not target.IsValid() or not err.Success():
 	sys.stderr.write("lldb: failed to setup up target: %s\n" % (err))
 	sys.exit(1)
 
-target.modules[0].SetPlatformFileSpec(lldb.SBFileSpec(device_exe))
-
 listener = debugger.GetListener()
-process = target.ConnectRemote(listener, 'connect://localhost:3222', None, err)
+
+if platform == 'remote-ios':
+	target.modules[0].SetPlatformFileSpec(lldb.SBFileSpec(device_exe_or_pid))
+	process = target.ConnectRemote(listener, 'connect://localhost:3222', None, err)
+else:
+	process = target.AttachToProcessWithID(listener, int(device_exe_or_pid), err)
+
 if not err.Success():
-	sys.stderr.write("lldb: failed to connect to remote target: %s\n" % (err))
+	sys.stderr.write("lldb: failed to connect to remote target %s: %s\n" % (device_exe_or_pid, err))
 	sys.exit(1)
 
 # Don't stop on signals.
@@ -777,6 +849,25 @@ for i in range(0, sigs.GetNumSignals()):
 event = lldb.SBEvent()
 running = False
 prev_handler = None
+
+def signal_handler(signal, frame):
+	process.Signal(signal)
+
+def run_program():
+	# Forward SIGQUIT to the program.
+	prev_handler = signal.signal(signal.SIGQUIT, signal_handler)
+	# Tell the Go driver that the program is running and should not be retried.
+	sys.stderr.write("lldb: running program\n")
+	running = True
+	# Process is stopped at attach/launch. Let it run.
+	process.Continue()
+
+if platform != 'remote-ios':
+	# For the local emulator the program is ready to run.
+	# For remote device runs, we need to wait for eStateConnected,
+	# below.
+	run_program()
+
 while True:
 	if not listener.WaitForEvent(1, event):
 		continue
@@ -800,24 +891,22 @@ while True:
 			signal.signal(signal.SIGQUIT, prev_handler)
 		break
 	elif state == lldb.eStateConnected:
-		process.RemoteLaunch(args, env, None, None, None, None, 0, False, err)
-		if not err.Success():
-			sys.stderr.write("lldb: failed to launch remote process: %s\n" % (err))
-			process.Kill()
-			debugger.Terminate()
-			sys.exit(1)
-		# Forward SIGQUIT to the program.
-		def signal_handler(signal, frame):
-			process.Signal(signal)
-		prev_handler = signal.signal(signal.SIGQUIT, signal_handler)
-		# Tell the Go driver that the program is running and should not be retried.
-		sys.stderr.write("lldb: running program\n")
-		running = True
-		# Process stops once at the beginning. Continue.
-		process.Continue()
+		if platform == 'remote-ios':
+			process.RemoteLaunch(args, env, None, None, None, None, 0, False, err)
+			if not err.Success():
+				sys.stderr.write("lldb: failed to launch remote process: %s\n" % (err))
+				process.Kill()
+				debugger.Terminate()
+				sys.exit(1)
+		run_program()
 
 exitStatus = process.GetExitStatus()
+exitDesc = process.GetExitDescription()
 process.Kill()
 debugger.Terminate()
+if exitStatus == 0 and exitDesc is not None:
+	# Ensure tests fail when killed by a signal.
+	exitStatus = 123
+
 sys.exit(exitStatus)
 `
diff --git a/misc/wasm/wasm_exec.js b/misc/wasm/wasm_exec.js
index ef97c4e311..82041e6bb9 100644
--- a/misc/wasm/wasm_exec.js
+++ b/misc/wasm/wasm_exec.js
@@ -102,7 +102,7 @@
 		}
 	}
 
-	if (!global.crypto) {
+	if (!global.crypto && global.require) {
 		const nodeCrypto = require("crypto");
 		global.crypto = {
 			getRandomValues(b) {
@@ -110,6 +110,9 @@
 			},
 		};
 	}
+	if (!global.crypto) {
+		throw new Error("global.crypto is not available, polyfill required (getRandomValues only)");
+	}
 
 	if (!global.performance) {
 		global.performance = {
@@ -120,13 +123,19 @@
 		};
 	}
 
-	if (!global.TextEncoder) {
+	if (!global.TextEncoder && global.require) {
 		global.TextEncoder = require("util").TextEncoder;
 	}
+	if (!global.TextEncoder) {
+		throw new Error("global.TextEncoder is not available, polyfill required");
+	}
 
-	if (!global.TextDecoder) {
+	if (!global.TextDecoder && global.require) {
 		global.TextDecoder = require("util").TextDecoder;
 	}
+	if (!global.TextDecoder) {
+		throw new Error("global.TextDecoder is not available, polyfill required");
+	}
 
 	// End of polyfills for common API.
 
@@ -255,6 +264,7 @@
 
 					// func wasmExit(code int32)
 					"runtime.wasmExit": (sp) => {
+						sp >>>= 0;
 						const code = this.mem.getInt32(sp + 8, true);
 						this.exited = true;
 						delete this._inst;
@@ -267,6 +277,7 @@
 
 					// func wasmWrite(fd uintptr, p unsafe.Pointer, n int32)
 					"runtime.wasmWrite": (sp) => {
+						sp >>>= 0;
 						const fd = getInt64(sp + 8);
 						const p = getInt64(sp + 16);
 						const n = this.mem.getInt32(sp + 24, true);
@@ -275,16 +286,19 @@
 
 					// func resetMemoryDataView()
 					"runtime.resetMemoryDataView": (sp) => {
+						sp >>>= 0;
 						this.mem = new DataView(this._inst.exports.mem.buffer);
 					},
 
 					// func nanotime1() int64
 					"runtime.nanotime1": (sp) => {
+						sp >>>= 0;
 						setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000);
 					},
 
 					// func walltime1() (sec int64, nsec int32)
 					"runtime.walltime1": (sp) => {
+						sp >>>= 0;
 						const msec = (new Date).getTime();
 						setInt64(sp + 8, msec / 1000);
 						this.mem.setInt32(sp + 16, (msec % 1000) * 1000000, true);
@@ -292,6 +306,7 @@
 
 					// func scheduleTimeoutEvent(delay int64) int32
 					"runtime.scheduleTimeoutEvent": (sp) => {
+						sp >>>= 0;
 						const id = this._nextCallbackTimeoutID;
 						this._nextCallbackTimeoutID++;
 						this._scheduledTimeouts.set(id, setTimeout(
@@ -311,6 +326,7 @@
 
 					// func clearTimeoutEvent(id int32)
 					"runtime.clearTimeoutEvent": (sp) => {
+						sp >>>= 0;
 						const id = this.mem.getInt32(sp + 8, true);
 						clearTimeout(this._scheduledTimeouts.get(id));
 						this._scheduledTimeouts.delete(id);
@@ -318,11 +334,13 @@
 
 					// func getRandomData(r []byte)
 					"runtime.getRandomData": (sp) => {
+						sp >>>= 0;
 						crypto.getRandomValues(loadSlice(sp + 8));
 					},
 
 					// func finalizeRef(v ref)
 					"syscall/js.finalizeRef": (sp) => {
+						sp >>>= 0;
 						const id = this.mem.getUint32(sp + 8, true);
 						this._goRefCounts[id]--;
 						if (this._goRefCounts[id] === 0) {
@@ -335,44 +353,51 @@
 
 					// func stringVal(value string) ref
 					"syscall/js.stringVal": (sp) => {
+						sp >>>= 0;
 						storeValue(sp + 24, loadString(sp + 8));
 					},
 
 					// func valueGet(v ref, p string) ref
 					"syscall/js.valueGet": (sp) => {
+						sp >>>= 0;
 						const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16));
-						sp = this._inst.exports.getsp(); // see comment above
+						sp = this._inst.exports.getsp() >>> 0; // see comment above
 						storeValue(sp + 32, result);
 					},
 
 					// func valueSet(v ref, p string, x ref)
 					"syscall/js.valueSet": (sp) => {
+						sp >>>= 0;
 						Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32));
 					},
 
 					// func valueDelete(v ref, p string)
 					"syscall/js.valueDelete": (sp) => {
+						sp >>>= 0;
 						Reflect.deleteProperty(loadValue(sp + 8), loadString(sp + 16));
 					},
 
 					// func valueIndex(v ref, i int) ref
 					"syscall/js.valueIndex": (sp) => {
+						sp >>>= 0;
 						storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16)));
 					},
 
 					// valueSetIndex(v ref, i int, x ref)
 					"syscall/js.valueSetIndex": (sp) => {
+						sp >>>= 0;
 						Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24));
 					},
 
 					// func valueCall(v ref, m string, args []ref) (ref, bool)
 					"syscall/js.valueCall": (sp) => {
+						sp >>>= 0;
 						try {
 							const v = loadValue(sp + 8);
 							const m = Reflect.get(v, loadString(sp + 16));
 							const args = loadSliceOfValues(sp + 32);
 							const result = Reflect.apply(m, v, args);
-							sp = this._inst.exports.getsp(); // see comment above
+							sp = this._inst.exports.getsp() >>> 0; // see comment above
 							storeValue(sp + 56, result);
 							this.mem.setUint8(sp + 64, 1);
 						} catch (err) {
@@ -383,11 +408,12 @@
 
 					// func valueInvoke(v ref, args []ref) (ref, bool)
 					"syscall/js.valueInvoke": (sp) => {
+						sp >>>= 0;
 						try {
 							const v = loadValue(sp + 8);
 							const args = loadSliceOfValues(sp + 16);
 							const result = Reflect.apply(v, undefined, args);
-							sp = this._inst.exports.getsp(); // see comment above
+							sp = this._inst.exports.getsp() >>> 0; // see comment above
 							storeValue(sp + 40, result);
 							this.mem.setUint8(sp + 48, 1);
 						} catch (err) {
@@ -398,11 +424,12 @@
 
 					// func valueNew(v ref, args []ref) (ref, bool)
 					"syscall/js.valueNew": (sp) => {
+						sp >>>= 0;
 						try {
 							const v = loadValue(sp + 8);
 							const args = loadSliceOfValues(sp + 16);
 							const result = Reflect.construct(v, args);
-							sp = this._inst.exports.getsp(); // see comment above
+							sp = this._inst.exports.getsp() >>> 0; // see comment above
 							storeValue(sp + 40, result);
 							this.mem.setUint8(sp + 48, 1);
 						} catch (err) {
@@ -413,11 +440,13 @@
 
 					// func valueLength(v ref) int
 					"syscall/js.valueLength": (sp) => {
+						sp >>>= 0;
 						setInt64(sp + 16, parseInt(loadValue(sp + 8).length));
 					},
 
 					// valuePrepareString(v ref) (ref, int)
 					"syscall/js.valuePrepareString": (sp) => {
+						sp >>>= 0;
 						const str = encoder.encode(String(loadValue(sp + 8)));
 						storeValue(sp + 16, str);
 						setInt64(sp + 24, str.length);
@@ -425,17 +454,20 @@
 
 					// valueLoadString(v ref, b []byte)
 					"syscall/js.valueLoadString": (sp) => {
+						sp >>>= 0;
 						const str = loadValue(sp + 8);
 						loadSlice(sp + 16).set(str);
 					},
 
 					// func valueInstanceOf(v ref, t ref) bool
 					"syscall/js.valueInstanceOf": (sp) => {
+						sp >>>= 0;
 						this.mem.setUint8(sp + 24, (loadValue(sp + 8) instanceof loadValue(sp + 16)) ? 1 : 0);
 					},
 
 					// func copyBytesToGo(dst []byte, src ref) (int, bool)
 					"syscall/js.copyBytesToGo": (sp) => {
+						sp >>>= 0;
 						const dst = loadSlice(sp + 8);
 						const src = loadValue(sp + 32);
 						if (!(src instanceof Uint8Array || src instanceof Uint8ClampedArray)) {
@@ -450,6 +482,7 @@
 
 					// func copyBytesToJS(dst ref, src []byte) (int, bool)
 					"syscall/js.copyBytesToJS": (sp) => {
+						sp >>>= 0;
 						const dst = loadValue(sp + 8);
 						const src = loadSlice(sp + 16);
 						if (!(dst instanceof Uint8Array || dst instanceof Uint8ClampedArray)) {
@@ -470,6 +503,9 @@
 		}
 
 		async run(instance) {
+			if (!(instance instanceof WebAssembly.Instance)) {
+				throw new Error("Go.run: WebAssembly.Instance expected");
+			}
 			this._inst = instance;
 			this.mem = new DataView(this._inst.exports.mem.buffer);
 			this._values = [ // JS values that Go currently has references to, indexed by reference id