unix: regenerate type Clockinfo on OpenBSD 6.9

OpenBSD 6.9 changed the definition of Clockinfo, leading
TestSysctlClockinfo to fail on OpenBSD 6.9 onwards. Since OpenBSD 6.8 is
no longer supported upstream, regenerate Clockinfo on that release and
test that SysctlClockInfo fails gracefully on OpenBSD 6.8 and earlier.

Fixes golang/go#47629
For golang/go#48977

Change-Id: Ia511b8601af11f70ffcce0f96764c69a67d626b8
Reviewed-on: https://go-review.googlesource.com/c/sys/+/360694
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>

unix/syscall_bsd_test.go

@@ -70,6 +70,14 @@ func TestSysctlUint32(t *testing.T) {
 func TestSysctlClockinfo(t *testing.T) {
 	ci, err := unix.SysctlClockinfo("kern.clockrate")
 	if err != nil {
+		if runtime.GOOS == "openbsd" && (err == unix.ENOMEM || err == unix.EIO) {
+			if osrev, _ := unix.SysctlUint32("kern.osrevision"); osrev <= 202010 {
+				// SysctlClockinfo should fail gracefully due to a struct size
+				// mismatch on OpenBSD 6.8 and earlier, see
+				// https://golang.org/issue/47629
+				return
+			}
+		}
 		t.Fatal(err)
 	}
 	t.Logf("tick = %v, hz = %v, profhz = %v, stathz = %v",

unix/ztypes_openbsd_386.go

@@ -564,12 +564,11 @@ type Uvmexp struct {
 	Kmapent            int32
 }
 
-const SizeofClockinfo = 0x14
+const SizeofClockinfo = 0x10
 
 type Clockinfo struct {
-	Hz      int32
-	Tick    int32
-	Tickadj int32
-	Stathz  int32
-	Profhz  int32
+	Hz     int32
+	Tick   int32
+	Stathz int32
+	Profhz int32
 }

unix/ztypes_openbsd_amd64.go

@@ -564,12 +564,11 @@ type Uvmexp struct {
 	Kmapent            int32
 }
 
-const SizeofClockinfo = 0x14
+const SizeofClockinfo = 0x10
 
 type Clockinfo struct {
-	Hz      int32
-	Tick    int32
-	Tickadj int32
-	Stathz  int32
-	Profhz  int32
+	Hz     int32
+	Tick   int32
+	Stathz int32
+	Profhz int32
 }

unix/ztypes_openbsd_arm.go

@@ -565,12 +565,11 @@ type Uvmexp struct {
 	Kmapent            int32
 }
 
-const SizeofClockinfo = 0x14
+const SizeofClockinfo = 0x10
 
 type Clockinfo struct {
-	Hz      int32
-	Tick    int32
-	Tickadj int32
-	Stathz  int32
-	Profhz  int32
+	Hz     int32
+	Tick   int32
+	Stathz int32
+	Profhz int32
 }

unix/ztypes_openbsd_arm64.go

@@ -558,12 +558,11 @@ type Uvmexp struct {
 	Kmapent            int32
 }
 
-const SizeofClockinfo = 0x14
+const SizeofClockinfo = 0x10
 
 type Clockinfo struct {
-	Hz      int32
-	Tick    int32
-	Tickadj int32
-	Stathz  int32
-	Profhz  int32
+	Hz     int32
+	Tick   int32
+	Stathz int32
+	Profhz int32
 }

unix/ztypes_openbsd_mips64.go

@@ -558,12 +558,11 @@ type Uvmexp struct {
 	Kmapent            int32
 }
 
-const SizeofClockinfo = 0x14
+const SizeofClockinfo = 0x10
 
 type Clockinfo struct {
-	Hz      int32
-	Tick    int32
-	Tickadj int32
-	Stathz  int32
-	Profhz  int32
+	Hz     int32
+	Tick   int32
+	Stathz int32
+	Profhz int32
 }