diff --git a/src/runtime/export_aix_test.go b/src/runtime/export_aix_test.go
new file mode 100644
index 0000000000..162552d04c
--- /dev/null
+++ b/src/runtime/export_aix_test.go
@@ -0,0 +1,7 @@
+// 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.
+
+package runtime
+
+var Fcntl = syscall_fcntl1
diff --git a/src/runtime/nbpipe_fcntl_aix_test.go b/src/runtime/nbpipe_fcntl_aix_test.go
new file mode 100644
index 0000000000..4276ed5b53
--- /dev/null
+++ b/src/runtime/nbpipe_fcntl_aix_test.go
@@ -0,0 +1,17 @@
+// 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.
+
+package runtime_test
+
+import (
+	"runtime"
+	"syscall"
+)
+
+// We can't call syscall.Syscall on AIX. Therefore, fcntl is exported from the
+// runtime in export_aix_test.go.
+func fcntl(fd uintptr, cmd int, arg uintptr) (uintptr, syscall.Errno) {
+	res, errno := runtime.Fcntl(fd, uintptr(cmd), arg)
+	return res, syscall.Errno(errno)
+}
diff --git a/src/runtime/nbpipe_fcntl_unix_test.go b/src/runtime/nbpipe_fcntl_unix_test.go
new file mode 100644
index 0000000000..06b3275f06
--- /dev/null
+++ b/src/runtime/nbpipe_fcntl_unix_test.go
@@ -0,0 +1,14 @@
+// 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 darwin dragonfly freebsd linux netbsd openbsd
+
+package runtime_test
+
+import "syscall"
+
+func fcntl(fd uintptr, cmd int, arg uintptr) (uintptr, syscall.Errno) {
+	res, _, err := syscall.Syscall(syscall.SYS_FCNTL, fd, uintptr(cmd), arg)
+	return res, err
+}
diff --git a/src/runtime/nbpipe_test.go b/src/runtime/nbpipe_test.go
index bd0d578234..00dc11e937 100644
--- a/src/runtime/nbpipe_test.go
+++ b/src/runtime/nbpipe_test.go
@@ -49,7 +49,7 @@ func checkIsPipe(t *testing.T, r, w int32) {
 
 func checkNonblocking(t *testing.T, fd int32, name string) {
 	t.Helper()
-	flags, _, errno := syscall.Syscall(syscall.SYS_FCNTL, uintptr(fd), syscall.F_GETFL, 0)
+	flags, errno := fcntl(uintptr(fd), syscall.F_GETFL, 0)
 	if errno != 0 {
 		t.Errorf("fcntl(%s, F_GETFL) failed: %v", name, syscall.Errno(errno))
 	} else if flags&syscall.O_NONBLOCK == 0 {
@@ -59,7 +59,7 @@ func checkNonblocking(t *testing.T, fd int32, name string) {
 
 func checkCloseonexec(t *testing.T, fd int32, name string) {
 	t.Helper()
-	flags, _, errno := syscall.Syscall(syscall.SYS_FCNTL, uintptr(fd), syscall.F_GETFD, 0)
+	flags, errno := fcntl(uintptr(fd), syscall.F_GETFD, 0)
 	if errno != 0 {
 		t.Errorf("fcntl(%s, F_GETFD) failed: %v", name, syscall.Errno(errno))
 	} else if flags&syscall.FD_CLOEXEC == 0 {