misc/cgo/test/testx.go - go - Git at Google

 // Copyright 2011 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.

 // Test cases for cgo.
 // Both the import "C" prologue and the main file are sorted by issue number.
 // This file contains //export directives on Go functions
 // and so it must NOT contain C definitions (only declarations).
 // See test.go for C definitions.

 package cgotest

 import (
 	"runtime"
 	"runtime/debug"
 	"strings"
 	"sync"
 	"sync/atomic"
 	"testing"
 	"time"
 	"unsafe"
 )

 /*
 // threads
 extern void doAdd(int, int);

 // issue 1328
 extern void BackIntoGo(void);
 void IntoC(void);

 // issue 1560
 // mysleep returns the absolute start time in ms.
 long long mysleep(int seconds);

 // twoSleep returns the absolute start time of the first sleep
 // in ms.
 long long twoSleep(int);

 // issue 3775
 void lockOSThreadCallback(void);
 inline static void lockOSThreadC(void)
 {
         lockOSThreadCallback();
 }
 int usleep(unsigned usec);

 // issue 4054 part 2 - part 1 in test.go
 typedef enum {
 	A = 0,
 	B,
 	C,
 	D,
 	E,
 	F,
 	G,
 	H,
 	II,
 	J,
 } issue4054b;

 // issue 5548

 extern int issue5548_in_c(void);

 // issue 6833

 extern unsigned long long issue6833Func(unsigned int, unsigned long long);

 // issue 6907

 extern int CheckIssue6907C(_GoString_);

 // issue 7665

 extern void f7665(void);

 // issue 7978
 // Stack tracing didn't work during cgo code after calling a Go
 // callback.  Make sure GC works and the stack trace is correct.

 #include <stdint.h>

 void issue7978cb(void);

 #if defined(__APPLE__) && defined(__arm__)
 // on Darwin/ARM, libSystem doesn't provide implementation of the __sync_fetch_and_add
 // primitive, and although gcc supports it, it doesn't inline its definition.
 // Clang could inline its definition, so we require clang on Darwin/ARM.
 #if defined(__clang__)
 #define HAS_SYNC_FETCH_AND_ADD 1
 #else
 #define HAS_SYNC_FETCH_AND_ADD 0
 #endif
 #else
 #define HAS_SYNC_FETCH_AND_ADD 1
 #endif

 // use ugly atomic variable sync since that doesn't require calling back into
 // Go code or OS dependencies
 static void issue7978c(uint32_t *sync) {
 #if HAS_SYNC_FETCH_AND_ADD
 	while(__sync_fetch_and_add(sync, 0) != 0)
 		;
 	__sync_fetch_and_add(sync, 1);
 	while(__sync_fetch_and_add(sync, 0) != 2)
 		;
 	issue7978cb();
 	__sync_fetch_and_add(sync, 1);
 	while(__sync_fetch_and_add(sync, 0) != 6)
 		;
 #endif
 }

 // issue 8331 part 2 - part 1 in test.go
 // A typedef of an unnamed struct is the same struct when
 // #include'd twice.  No runtime test; just make sure it compiles.
 #include "issue8331.h"

 // issue 20910
 void callMulti(void);

 // issue 28772 part 2 - part 1 in issuex.go
 #define issue28772Constant2 2

 */
 import "C"

 // exports

 //export ReturnIntLong
 func ReturnIntLong() (int, C.long) {
 	return 1, 2
 }

 //export gc
 func gc() {
 	runtime.GC()
 }

 // threads

 var sum struct {
 	sync.Mutex
 	i int
 }

 //export Add
 func Add(x int) {
 	defer func() {
 		recover()
 	}()
 	sum.Lock()
 	sum.i += x
 	sum.Unlock()
 	var p *int
 	*p = 2
 }

 func testCthread(t *testing.T) {
 	if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
 		t.Skip("the iOS exec wrapper is unable to properly handle the panic from Add")
 	}
 	sum.i = 0
 	C.doAdd(10, 6)

 	want := 10 * (10 - 1) / 2 * 6
 	if sum.i != want {
 		t.Fatalf("sum=%d, want %d", sum.i, want)
 	}
 }

 // issue 1328

 //export BackIntoGo
 func BackIntoGo() {
 	x := 1

 	for i := 0; i < 10000; i++ {
 		xvariadic(x)
 		if x != 1 {
 			panic("x is not 1?")
 		}
 	}
 }

 func xvariadic(x ...interface{}) {
 }

 func test1328(t *testing.T) {
 	C.IntoC()
 }

 // issue 1560

 var sleepDone = make(chan int64)

 // parallelSleep returns the absolute difference between the start time
 // of the two sleeps.
 func parallelSleep(n int) int64 {
 	t := int64(C.twoSleep(C.int(n))) - <-sleepDone
 	if t < 0 {
 		return -t
 	}
 	return t
 }

 //export BackgroundSleep
 func BackgroundSleep(n int32) {
 	go func() {
 		sleepDone <- int64(C.mysleep(C.int(n)))
 	}()
 }

 func testParallelSleep(t *testing.T) {
 	sleepSec := 1
 	dt := time.Duration(parallelSleep(sleepSec)) * time.Millisecond
 	t.Logf("difference in start time for two sleep(%d) is %v", sleepSec, dt)
 	// bug used to run sleeps in serial, producing a 2*sleepSec-second delay.
 	// we detect if the start times of those sleeps are > 0.5*sleepSec-second.
 	if dt >= time.Duration(sleepSec)*time.Second/2 {
 		t.Fatalf("parallel %d-second sleeps slept for %f seconds", sleepSec, dt.Seconds())
 	}
 }

 // issue 2462

 //export exportbyte
 func exportbyte() byte {
 	return 0
 }

 //export exportbool
 func exportbool() bool {
 	return false
 }

 //export exportrune
 func exportrune() rune {
 	return 0
 }

 //export exporterror
 func exporterror() error {
 	return nil
 }

 //export exportint
 func exportint() int {
 	return 0
 }

 //export exportuint
 func exportuint() uint {
 	return 0
 }

 //export exportuintptr
 func exportuintptr() uintptr {
 	return (uintptr)(0)
 }

 //export exportint8
 func exportint8() int8 {
 	return 0
 }

 //export exportuint8
 func exportuint8() uint8 {
 	return 0
 }

 //export exportint16
 func exportint16() int16 {
 	return 0
 }

 //export exportuint16
 func exportuint16() uint16 {
 	return 0
 }

 //export exportint32
 func exportint32() int32 {
 	return 0
 }

 //export exportuint32
 func exportuint32() uint32 {
 	return 0
 }

 //export exportint64
 func exportint64() int64 {
 	return 0
 }

 //export exportuint64
 func exportuint64() uint64 {
 	return 0
 }

 //export exportfloat32
 func exportfloat32() float32 {
 	return 0
 }

 //export exportfloat64
 func exportfloat64() float64 {
 	return 0
 }

 //export exportcomplex64
 func exportcomplex64() complex64 {
 	return 0
 }

 //export exportcomplex128
 func exportcomplex128() complex128 {
 	return 0
 }

 // issue 3741

 //export exportSliceIn
 func exportSliceIn(s []byte) bool {
 	return len(s) == cap(s)
 }

 //export exportSliceOut
 func exportSliceOut() []byte {
 	return []byte{1}
 }

 //export exportSliceInOut
 func exportSliceInOut(s []byte) []byte {
 	return s
 }

 // issue 3775

 func init() {
 	if runtime.GOOS == "android" {
 		return
 	}
 	// Same as test3775 but run during init so that
 	// there are two levels of internal runtime lock
 	// (1 for init, 1 for cgo).
 	// This would have been broken by CL 11663043.
 	C.lockOSThreadC()
 }

 func test3775(t *testing.T) {
 	if runtime.GOOS == "android" {
 		return
 	}
 	// Used to panic because of the UnlockOSThread below.
 	C.lockOSThreadC()
 }

 //export lockOSThreadCallback
 func lockOSThreadCallback() {
 	runtime.LockOSThread()
 	runtime.UnlockOSThread()
 	go C.usleep(10000)
 	runtime.Gosched()
 }

 // issue 4054 part 2 - part 1 in test.go

 var issue4054b = []int{C.A, C.B, C.C, C.D, C.E, C.F, C.G, C.H, C.II, C.J}

 //export issue5548FromC
 func issue5548FromC(s string, i int) int {
 	if len(s) == 4 && s == "test" && i == 42 {
 		return 12345
 	}
 	println("got", len(s), i)
 	return 9876
 }

 func test5548(t *testing.T) {
 	if x := C.issue5548_in_c(); x != 12345 {
 		t.Errorf("issue5548_in_c = %d, want %d", x, 12345)
 	}
 }

 // issue 6833

 //export GoIssue6833Func
 func GoIssue6833Func(aui uint, aui64 uint64) uint64 {
 	return aui64 + uint64(aui)
 }

 func test6833(t *testing.T) {
 	ui := 7
 	ull := uint64(0x4000300020001000)
 	v := uint64(C.issue6833Func(C.uint(ui), C.ulonglong(ull)))
 	exp := uint64(ui) + ull
 	if v != exp {
 		t.Errorf("issue6833Func() returns %x, expected %x", v, exp)
 	}
 }

 // issue 6907

 const CString = "C string"

 //export CheckIssue6907Go
 func CheckIssue6907Go(s string) C.int {
 	if s == CString {
 		return 1
 	}
 	return 0
 }

 func test6907Go(t *testing.T) {
 	if got := C.CheckIssue6907C(CString); got != 1 {
 		t.Errorf("C.CheckIssue6907C() == %d, want %d", got, 1)
 	}
 }

 // issue 7665

 //export f7665
 func f7665() {}

 var bad7665 unsafe.Pointer = C.f7665
 var good7665 uintptr = uintptr(C.f7665)

 func test7665(t *testing.T) {
 	if bad7665 == nil || uintptr(bad7665) != good7665 {
 		t.Errorf("ptrs = %p, %#x, want same non-nil pointer", bad7665, good7665)
 	}
 }

 // issue 7978

 var issue7978sync uint32

 func issue7978check(t *testing.T, wantFunc string, badFunc string, depth int) {
 	runtime.GC()
 	buf := make([]byte, 65536)
 	trace := string(buf[:runtime.Stack(buf, true)])
 	for _, goroutine := range strings.Split(trace, "\n\n") {
 		if strings.Contains(goroutine, "test.issue7978go") {
 			trace := strings.Split(goroutine, "\n")
 			// look for the expected function in the stack
 			for i := 0; i < depth; i++ {
 				if badFunc != "" && strings.Contains(trace[1+2*i], badFunc) {
 					t.Errorf("bad stack: found %s in the stack:\n%s", badFunc, goroutine)
 					return
 				}
 				if strings.Contains(trace[1+2*i], wantFunc) {
 					return
 				}
 			}
 			t.Errorf("bad stack: didn't find %s in the stack:\n%s", wantFunc, goroutine)
 			return
 		}
 	}
 	t.Errorf("bad stack: goroutine not found. Full stack dump:\n%s", trace)
 }

 func issue7978wait(store uint32, wait uint32) {
 	if store != 0 {
 		atomic.StoreUint32(&issue7978sync, store)
 	}
 	for atomic.LoadUint32(&issue7978sync) != wait {
 		runtime.Gosched()
 	}
 }

 //export issue7978cb
 func issue7978cb() {
 	// Force a stack growth from the callback to put extra
 	// pressure on the runtime. See issue #17785.
 	growStack(64)
 	issue7978wait(3, 4)
 }

 func growStack(n int) int {
 	var buf [128]int
 	if n == 0 {
 		return 0
 	}
 	return buf[growStack(n-1)]
 }

 func issue7978go() {
 	C.issue7978c((*C.uint32_t)(&issue7978sync))
 	issue7978wait(7, 8)
 }

 func test7978(t *testing.T) {
 	if runtime.Compiler == "gccgo" {
 		t.Skip("gccgo can not do stack traces of C code")
 	}
 	if C.HAS_SYNC_FETCH_AND_ADD == 0 {
 		t.Skip("clang required for __sync_fetch_and_add support on darwin/arm")
 	}
 	debug.SetTraceback("2")
 	issue7978sync = 0
 	go issue7978go()
 	// test in c code, before callback
 	issue7978wait(0, 1)
 	issue7978check(t, "_Cfunc_issue7978c(", "", 1)
 	// test in go code, during callback
 	issue7978wait(2, 3)
 	issue7978check(t, "test.issue7978cb(", "test.issue7978go", 3)
 	// test in c code, after callback
 	issue7978wait(4, 5)
 	issue7978check(t, "_Cfunc_issue7978c(", "_cgoexpwrap", 1)
 	// test in go code, after return from cgo
 	issue7978wait(6, 7)
 	issue7978check(t, "test.issue7978go(", "", 3)
 	atomic.StoreUint32(&issue7978sync, 8)
 }

 // issue 8331 part 2

 var issue8331Var C.issue8331

 // issue 20910

 //export multi
 func multi() (*C.char, C.int) {
 	return C.CString("multi"), 0
 }

 func test20910(t *testing.T) {
 	C.callMulti()
 }

 // issue 28772 part 2

 const issue28772Constant2 = C.issue28772Constant2
	// Copyright 2011 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.

	// Test cases for cgo.
	// Both the import "C" prologue and the main file are sorted by issue number.
	// This file contains //export directives on Go functions
	// and so it must NOT contain C definitions (only declarations).
	// See test.go for C definitions.

	package cgotest

	import (
	"runtime"
	"runtime/debug"
	"strings"
	"sync"
	"sync/atomic"
	"testing"
	"time"
	"unsafe"
	)

	/*
	// threads
	extern void doAdd(int, int);

	// issue 1328
	extern void BackIntoGo(void);
	void IntoC(void);

	// issue 1560
	// mysleep returns the absolute start time in ms.
	long long mysleep(int seconds);

	// twoSleep returns the absolute start time of the first sleep
	// in ms.
	long long twoSleep(int);

	// issue 3775
	void lockOSThreadCallback(void);
	inline static void lockOSThreadC(void)
	{
	lockOSThreadCallback();
	}
	int usleep(unsigned usec);

	// issue 4054 part 2 - part 1 in test.go
	typedef enum {
	A = 0,
	B,
	C,
	D,
	E,
	F,
	G,
	H,
	II,
	J,
	} issue4054b;

	// issue 5548

	extern int issue5548_in_c(void);

	// issue 6833

	extern unsigned long long issue6833Func(unsigned int, unsigned long long);

	// issue 6907

	extern int CheckIssue6907C(_GoString_);

	// issue 7665

	extern void f7665(void);

	// issue 7978
	// Stack tracing didn't work during cgo code after calling a Go
	// callback. Make sure GC works and the stack trace is correct.

	#include <stdint.h>

	void issue7978cb(void);

	#if defined(__APPLE__) && defined(__arm__)
	// on Darwin/ARM, libSystem doesn't provide implementation of the __sync_fetch_and_add
	// primitive, and although gcc supports it, it doesn't inline its definition.
	// Clang could inline its definition, so we require clang on Darwin/ARM.
	#if defined(__clang__)
	#define HAS_SYNC_FETCH_AND_ADD 1
	#else
	#define HAS_SYNC_FETCH_AND_ADD 0
	#endif
	#else
	#define HAS_SYNC_FETCH_AND_ADD 1
	#endif

	// use ugly atomic variable sync since that doesn't require calling back into
	// Go code or OS dependencies
	static void issue7978c(uint32_t *sync) {
	#if HAS_SYNC_FETCH_AND_ADD
	while(__sync_fetch_and_add(sync, 0) != 0)
	;
	__sync_fetch_and_add(sync, 1);
	while(__sync_fetch_and_add(sync, 0) != 2)
	;
	issue7978cb();
	__sync_fetch_and_add(sync, 1);
	while(__sync_fetch_and_add(sync, 0) != 6)
	;
	#endif
	}

	// issue 8331 part 2 - part 1 in test.go
	// A typedef of an unnamed struct is the same struct when
	// #include'd twice. No runtime test; just make sure it compiles.
	#include "issue8331.h"

	// issue 20910
	void callMulti(void);

	// issue 28772 part 2 - part 1 in issuex.go
	#define issue28772Constant2 2

	*/
	import "C"

	// exports

	//export ReturnIntLong
	func ReturnIntLong() (int, C.long) {
	return 1, 2
	}

	//export gc
	func gc() {
	runtime.GC()
	}

	// threads

	var sum struct {
	sync.Mutex
	i int
	}

	//export Add
	func Add(x int) {
	defer func() {
	recover()
	}()
	sum.Lock()
	sum.i += x
	sum.Unlock()
	var p *int
	*p = 2
	}

	func testCthread(t *testing.T) {
	if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" \|\| runtime.GOARCH == "arm64") {
	t.Skip("the iOS exec wrapper is unable to properly handle the panic from Add")
	}
	sum.i = 0
	C.doAdd(10, 6)

	want := 10 * (10 - 1) / 2 * 6
	if sum.i != want {
	t.Fatalf("sum=%d, want %d", sum.i, want)
	}
	}

	// issue 1328

	//export BackIntoGo
	func BackIntoGo() {
	x := 1

	for i := 0; i < 10000; i++ {
	xvariadic(x)
	if x != 1 {
	panic("x is not 1?")
	}
	}
	}

	func xvariadic(x ...interface{}) {
	}

	func test1328(t *testing.T) {
	C.IntoC()
	}

	// issue 1560

	var sleepDone = make(chan int64)

	// parallelSleep returns the absolute difference between the start time
	// of the two sleeps.
	func parallelSleep(n int) int64 {
	t := int64(C.twoSleep(C.int(n))) - <-sleepDone
	if t < 0 {
	return -t
	}
	return t
	}

	//export BackgroundSleep
	func BackgroundSleep(n int32) {
	go func() {
	sleepDone <- int64(C.mysleep(C.int(n)))
	}()
	}

	func testParallelSleep(t *testing.T) {
	sleepSec := 1
	dt := time.Duration(parallelSleep(sleepSec)) * time.Millisecond
	t.Logf("difference in start time for two sleep(%d) is %v", sleepSec, dt)
	// bug used to run sleeps in serial, producing a 2*sleepSec-second delay.
	// we detect if the start times of those sleeps are > 0.5*sleepSec-second.
	if dt >= time.Duration(sleepSec)*time.Second/2 {
	t.Fatalf("parallel %d-second sleeps slept for %f seconds", sleepSec, dt.Seconds())
	}
	}

	// issue 2462

	//export exportbyte
	func exportbyte() byte {
	return 0
	}

	//export exportbool
	func exportbool() bool {
	return false
	}

	//export exportrune
	func exportrune() rune {
	return 0
	}

	//export exporterror
	func exporterror() error {
	return nil
	}

	//export exportint
	func exportint() int {
	return 0
	}

	//export exportuint
	func exportuint() uint {
	return 0
	}

	//export exportuintptr
	func exportuintptr() uintptr {
	return (uintptr)(0)
	}

	//export exportint8
	func exportint8() int8 {
	return 0
	}

	//export exportuint8
	func exportuint8() uint8 {
	return 0
	}

	//export exportint16
	func exportint16() int16 {
	return 0
	}

	//export exportuint16
	func exportuint16() uint16 {
	return 0
	}

	//export exportint32
	func exportint32() int32 {
	return 0
	}

	//export exportuint32
	func exportuint32() uint32 {
	return 0
	}

	//export exportint64
	func exportint64() int64 {
	return 0
	}

	//export exportuint64
	func exportuint64() uint64 {
	return 0
	}

	//export exportfloat32
	func exportfloat32() float32 {
	return 0
	}

	//export exportfloat64
	func exportfloat64() float64 {
	return 0
	}

	//export exportcomplex64
	func exportcomplex64() complex64 {
	return 0
	}

	//export exportcomplex128
	func exportcomplex128() complex128 {
	return 0
	}

	// issue 3741

	//export exportSliceIn
	func exportSliceIn(s []byte) bool {
	return len(s) == cap(s)
	}

	//export exportSliceOut
	func exportSliceOut() []byte {
	return []byte{1}
	}

	//export exportSliceInOut
	func exportSliceInOut(s []byte) []byte {
	return s
	}

	// issue 3775

	func init() {
	if runtime.GOOS == "android" {
	return
	}
	// Same as test3775 but run during init so that
	// there are two levels of internal runtime lock
	// (1 for init, 1 for cgo).
	// This would have been broken by CL 11663043.
	C.lockOSThreadC()
	}

	func test3775(t *testing.T) {
	if runtime.GOOS == "android" {
	return
	}
	// Used to panic because of the UnlockOSThread below.
	C.lockOSThreadC()
	}

	//export lockOSThreadCallback
	func lockOSThreadCallback() {
	runtime.LockOSThread()
	runtime.UnlockOSThread()
	go C.usleep(10000)
	runtime.Gosched()
	}

	// issue 4054 part 2 - part 1 in test.go

	var issue4054b = []int{C.A, C.B, C.C, C.D, C.E, C.F, C.G, C.H, C.II, C.J}

	//export issue5548FromC
	func issue5548FromC(s string, i int) int {
	if len(s) == 4 && s == "test" && i == 42 {
	return 12345
	}
	println("got", len(s), i)
	return 9876
	}

	func test5548(t *testing.T) {
	if x := C.issue5548_in_c(); x != 12345 {
	t.Errorf("issue5548_in_c = %d, want %d", x, 12345)
	}
	}

	// issue 6833

	//export GoIssue6833Func
	func GoIssue6833Func(aui uint, aui64 uint64) uint64 {
	return aui64 + uint64(aui)
	}

	func test6833(t *testing.T) {
	ui := 7
	ull := uint64(0x4000300020001000)
	v := uint64(C.issue6833Func(C.uint(ui), C.ulonglong(ull)))
	exp := uint64(ui) + ull
	if v != exp {
	t.Errorf("issue6833Func() returns %x, expected %x", v, exp)
	}
	}

	// issue 6907

	const CString = "C string"

	//export CheckIssue6907Go
	func CheckIssue6907Go(s string) C.int {
	if s == CString {
	return 1
	}
	return 0
	}

	func test6907Go(t *testing.T) {
	if got := C.CheckIssue6907C(CString); got != 1 {
	t.Errorf("C.CheckIssue6907C() == %d, want %d", got, 1)
	}
	}

	// issue 7665

	//export f7665
	func f7665() {}

	var bad7665 unsafe.Pointer = C.f7665
	var good7665 uintptr = uintptr(C.f7665)

	func test7665(t *testing.T) {
	if bad7665 == nil \|\| uintptr(bad7665) != good7665 {
	t.Errorf("ptrs = %p, %#x, want same non-nil pointer", bad7665, good7665)
	}
	}

	// issue 7978

	var issue7978sync uint32

	func issue7978check(t *testing.T, wantFunc string, badFunc string, depth int) {
	runtime.GC()
	buf := make([]byte, 65536)
	trace := string(buf[:runtime.Stack(buf, true)])
	for _, goroutine := range strings.Split(trace, "\n\n") {
	if strings.Contains(goroutine, "test.issue7978go") {
	trace := strings.Split(goroutine, "\n")
	// look for the expected function in the stack
	for i := 0; i < depth; i++ {
	if badFunc != "" && strings.Contains(trace[1+2*i], badFunc) {
	t.Errorf("bad stack: found %s in the stack:\n%s", badFunc, goroutine)
	return
	}
	if strings.Contains(trace[1+2*i], wantFunc) {
	return
	}
	}
	t.Errorf("bad stack: didn't find %s in the stack:\n%s", wantFunc, goroutine)
	return
	}
	}
	t.Errorf("bad stack: goroutine not found. Full stack dump:\n%s", trace)
	}

	func issue7978wait(store uint32, wait uint32) {
	if store != 0 {
	atomic.StoreUint32(&issue7978sync, store)
	}
	for atomic.LoadUint32(&issue7978sync) != wait {
	runtime.Gosched()
	}
	}

	//export issue7978cb
	func issue7978cb() {
	// Force a stack growth from the callback to put extra
	// pressure on the runtime. See issue #17785.
	growStack(64)
	issue7978wait(3, 4)
	}

	func growStack(n int) int {
	var buf [128]int
	if n == 0 {
	return 0
	}
	return buf[growStack(n-1)]
	}

	func issue7978go() {
	C.issue7978c((*C.uint32_t)(&issue7978sync))
	issue7978wait(7, 8)
	}

	func test7978(t *testing.T) {
	if runtime.Compiler == "gccgo" {
	t.Skip("gccgo can not do stack traces of C code")
	}
	if C.HAS_SYNC_FETCH_AND_ADD == 0 {
	t.Skip("clang required for __sync_fetch_and_add support on darwin/arm")
	}
	debug.SetTraceback("2")
	issue7978sync = 0
	go issue7978go()
	// test in c code, before callback
	issue7978wait(0, 1)
	issue7978check(t, "_Cfunc_issue7978c(", "", 1)
	// test in go code, during callback
	issue7978wait(2, 3)
	issue7978check(t, "test.issue7978cb(", "test.issue7978go", 3)
	// test in c code, after callback
	issue7978wait(4, 5)
	issue7978check(t, "_Cfunc_issue7978c(", "_cgoexpwrap", 1)
	// test in go code, after return from cgo
	issue7978wait(6, 7)
	issue7978check(t, "test.issue7978go(", "", 3)
	atomic.StoreUint32(&issue7978sync, 8)
	}

	// issue 8331 part 2

	var issue8331Var C.issue8331

	// issue 20910

	//export multi
	func multi() (*C.char, C.int) {
	return C.CString("multi"), 0
	}

	func test20910(t *testing.T) {
	C.callMulti()
	}

	// issue 28772 part 2

	const issue28772Constant2 = C.issue28772Constant2