all: merge master into release-branch.go1.7

7a622740 net/http: make Transport use new connection if over HTTP/2 concurrency limit
219ca602 doc: fix required OS X version inconsistency for binary downloads
26015b95 runtime: make stack 16-byte aligned for external code in _rt0_amd64_linux_lib
9fde86b0 runtime, syscall: fix kernel gettimeofday ABI change on iOS 10
3a03e877 os: check for waitid returning ENOSYS
10316757 net/http: update bundled http2 for flow control window adjustment fix
da070bed syscall: fix Gettimeofday on macOS Sierra
f135c326 runtime: initialize hash algs before typemap

Change-Id: Ie176f3db1e253d75ae8e56b16d3fd9900b37dde3

doc/install.html

@@ -17,7 +17,7 @@
 <p>
 <a href="https://golang.org/dl/" target="_blank">Official binary
 distributions</a> are available for the FreeBSD (release 8-STABLE and above),
-Linux, Mac OS X (10.7 and above), and Windows operating systems and
+Linux, Mac OS X (10.8 and above), and Windows operating systems and
 the 32-bit (<code>386</code>) and 64-bit (<code>amd64</code>) x86 processor
 architectures.
 </p>
@@ -49,7 +49,7 @@ If your OS or architecture is not on the list, you may be able to
 <tr><td colspan="3"><hr></td></tr>
 <tr><td>FreeBSD 8-STABLE or later</td> <td>amd64</td> <td>Debian GNU/kFreeBSD not supported</td></tr>
 <tr><td>Linux 2.6.23 or later with glibc</td> <td>amd64, 386, arm</td> <td>CentOS/RHEL 5.x not supported</td></tr>
-<tr><td>Mac OS X 10.7 or later</td> <td>amd64</td> <td>use the clang or gcc<sup>&#8224;</sup> that comes with Xcode<sup>&#8225;</sup></td></tr>
+<tr><td>Mac OS X 10.7 or later</td> <td>amd64</td> <td>use the clang or gcc<sup>&#8224;</sup> that comes with Xcode<sup>&#8225;</sup> for <code>cgo</code> support</td></tr>
 <tr><td>Windows XP or later</td> <td>amd64, 386</td> <td>use MinGW gcc<sup>&#8224;</sup>. No need for cygwin or msys.</td></tr>
 </table>
 

src/net/http/transport.go

@@ -398,6 +398,15 @@ func (t *Transport) RoundTrip(req *Request) (*Response, error) {
 // HTTP request on a new connection. The non-nil input error is the
 // error from roundTrip.
 func (pc *persistConn) shouldRetryRequest(req *Request, err error) bool {
+	if err == http2ErrNoCachedConn {
+		// Issue 16582: if the user started a bunch of
+		// requests at once, they can all pick the same conn
+		// and violate the server's max concurrent streams.
+		// Instead, match the HTTP/1 behavior for now and dial
+		// again to get a new TCP connection, rather than failing
+		// this request.
+		return true
+	}
 	if err == errMissingHost {
 		// User error.
 		return false

src/os/wait_waitid.go

@@ -28,6 +28,12 @@ func (p *Process) blockUntilWaitable() (bool, error) {
 	_, _, e := syscall.Syscall6(syscall.SYS_WAITID, _P_PID, uintptr(p.Pid), uintptr(unsafe.Pointer(psig)), syscall.WEXITED|syscall.WNOWAIT, 0, 0)
 	runtime.KeepAlive(psig)
 	if e != 0 {
+		// waitid has been available since Linux 2.6.9, but
+		// reportedly is not available in Ubuntu on Windows.
+		// See issue 16610.
+		if e == syscall.ENOSYS {
+			return false, nil
+		}
 		return false, NewSyscallError("waitid", e)
 	}
 	return true, nil

src/runtime/alg.go

@@ -289,7 +289,7 @@ var aeskeysched [hashRandomBytes]byte
 // used in hash{32,64}.go to seed the hash function
 var hashkey [4]uintptr
 
-func init() {
+func alginit() {
 	// Install aes hash algorithm if we have the instructions we need
 	if (GOARCH == "386" || GOARCH == "amd64") &&
 		GOOS != "nacl" &&

src/runtime/proc.go

@@ -439,7 +439,8 @@ func schedinit() {
 	stackinit()
 	mallocinit()
 	mcommoninit(_g_.m)
-	typelinksinit()
+	alginit()       // maps must not be used before this call
+	typelinksinit() // uses maps
 	itabsinit()
 
 	msigsave(_g_.m)

src/runtime/rt0_linux_amd64.s

@@ -12,13 +12,18 @@ TEXT _rt0_amd64_linux(SB),NOSPLIT,$-8
 
 // When building with -buildmode=c-shared, this symbol is called when the shared
 // library is loaded.
-TEXT _rt0_amd64_linux_lib(SB),NOSPLIT,$0x48
+// Note: This function calls external C code, which might required 16-byte stack
+// alignment after cmd/internal/obj applies its transformations.
+TEXT _rt0_amd64_linux_lib(SB),NOSPLIT,$0x50
+	MOVQ	SP, AX
+	ANDQ	$-16, SP
 	MOVQ	BX, 0x10(SP)
 	MOVQ	BP, 0x18(SP)
 	MOVQ	R12, 0x20(SP)
 	MOVQ	R13, 0x28(SP)
 	MOVQ	R14, 0x30(SP)
 	MOVQ	R15, 0x38(SP)
+	MOVQ	AX, 0x40(SP)
 
 	MOVQ	DI, _rt0_amd64_linux_lib_argc<>(SB)
 	MOVQ	SI, _rt0_amd64_linux_lib_argv<>(SB)
@@ -50,6 +55,7 @@ restore:
 	MOVQ	0x28(SP), R13
 	MOVQ	0x30(SP), R14
 	MOVQ	0x38(SP), R15
+	MOVQ	0x40(SP), SP
 	RET
 
 TEXT _rt0_amd64_linux_lib_go(SB),NOSPLIT,$0

src/runtime/sys_darwin_arm.s

@@ -162,11 +162,15 @@ TEXT runtime·mincore(SB),NOSPLIT,$0
 TEXT time·now(SB), 7, $32
 	MOVW	$8(R13), R0  // timeval
 	MOVW	$0, R1  // zone
+	MOVW	$0, R2	// see issue 16570
 	MOVW	$SYS_gettimeofday, R12
 	SWI	$0x80 // Note: R0 is tv_sec, R1 is tv_usec
-
+	CMP	$0, R0
+	BNE	inreg
+	MOVW	8(R13), R0
+	MOVW	12(R13), R1
+inreg:
 	MOVW    R1, R2  // usec
-
 	MOVW	R0, sec+0(FP)
 	MOVW	$0, R1
 	MOVW	R1, loc+4(FP)
@@ -178,9 +182,14 @@ TEXT time·now(SB), 7, $32
 TEXT runtime·nanotime(SB),NOSPLIT,$32
 	MOVW	$8(R13), R0  // timeval
 	MOVW	$0, R1  // zone
+	MOVW	$0, R2	// see issue 16570
 	MOVW	$SYS_gettimeofday, R12
 	SWI	$0x80 // Note: R0 is tv_sec, R1 is tv_usec
-
+	CMP	$0, R0
+	BNE	inreg
+	MOVW	8(R13), R0
+	MOVW	12(R13), R1
+inreg:
 	MOVW    R1, R2
 	MOVW	$1000000000, R3
 	MULLU	R0, R3, (R1, R0)

src/runtime/sys_darwin_arm64.s

@@ -155,9 +155,14 @@ TEXT time·now(SB),NOSPLIT,$40-12
 	MOVD	RSP, R0	// timeval
 	MOVD	R0, R9	// this is how dyld calls gettimeofday
 	MOVW	$0, R1	// zone
+	MOVD	$0, R2	// see issue 16570
 	MOVW	$SYS_gettimeofday, R16
 	SVC	$0x80	// Note: x0 is tv_sec, w1 is tv_usec
-
+	CMP	$0, R0
+	BNE	inreg
+	MOVD	0(RSP), R0
+	MOVW	8(RSP), R1
+inreg:
 	MOVD	R0, sec+0(FP)
 	MOVW	$1000, R3
 	MUL	R3, R1
@@ -168,9 +173,14 @@ TEXT runtime·nanotime(SB),NOSPLIT,$40
 	MOVD	RSP, R0	// timeval
 	MOVD	R0, R9	// this is how dyld calls gettimeofday
 	MOVW	$0, R1	// zone
+	MOVD	$0, R2	// see issue 16570
 	MOVW	$SYS_gettimeofday, R16
 	SVC	$0x80	// Note: x0 is tv_sec, w1 is tv_usec
-
+	CMP	$0, R0
+	BNE	inreg
+	MOVD	0(RSP), R0
+	MOVW	8(RSP), R1
+inreg:
 	MOVW	$1000000000, R3
 	MUL	R3, R0
 	MOVW	$1000, R3

src/syscall/syscall_darwin_386.go

@@ -26,14 +26,21 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 }
 
 //sysnb	gettimeofday(tp *Timeval) (sec int32, usec int32, err error)
-func Gettimeofday(tv *Timeval) (err error) {
-	// The tv passed to gettimeofday must be non-nil
-	// but is otherwise unused. The answers come back
-	// in the two registers.
+func Gettimeofday(tv *Timeval) error {
+	// The tv passed to gettimeofday must be non-nil.
+	// Before macOS Sierra (10.12), tv was otherwise unused and
+	// the answers came back in the two registers.
+	// As of Sierra, gettimeofday return zeros and populates
+	// tv itself.
 	sec, usec, err := gettimeofday(tv)
+	if err != nil {
+		return err
+	}
+	if sec != 0 || usec != 0 {
 		tv.Sec = int32(sec)
 		tv.Usec = int32(usec)
-	return err
+	}
+	return nil
 }
 
 func SetKevent(k *Kevent_t, fd, mode, flags int) {

src/syscall/syscall_darwin_amd64.go

@@ -26,14 +26,21 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 }
 
 //sysnb	gettimeofday(tp *Timeval) (sec int64, usec int32, err error)
-func Gettimeofday(tv *Timeval) (err error) {
-	// The tv passed to gettimeofday must be non-nil
-	// but is otherwise unused. The answers come back
-	// in the two registers.
+func Gettimeofday(tv *Timeval) error {
+	// The tv passed to gettimeofday must be non-nil.
+	// Before macOS Sierra (10.12), tv was otherwise unused and
+	// the answers came back in the two registers.
+	// As of Sierra, gettimeofday return zeros and populates
+	// tv itself.
 	sec, usec, err := gettimeofday(tv)
+	if err != nil {
+		return err
+	}
+	if sec != 0 || usec != 0 {
 		tv.Sec = sec
 		tv.Usec = usec
-	return err
+	}
+	return nil
 }
 
 func SetKevent(k *Kevent_t, fd, mode, flags int) {

src/syscall/syscall_darwin_arm.go

@@ -26,14 +26,19 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 }
 
 //sysnb	gettimeofday(tp *Timeval) (sec int32, usec int32, err error)
-func Gettimeofday(tv *Timeval) (err error) {
+func Gettimeofday(tv *Timeval) error {
 	// The tv passed to gettimeofday must be non-nil
 	// but is otherwise unused. The answers come back
 	// in the two registers.
 	sec, usec, err := gettimeofday(tv)
+	if err != nil {
+		return err
+	}
+	if sec != 0 || usec != 0 {
 		tv.Sec = int32(sec)
 		tv.Usec = int32(usec)
-	return err
+	}
+	return nil
 }
 
 func SetKevent(k *Kevent_t, fd, mode, flags int) {

src/syscall/syscall_darwin_arm64.go

@@ -26,14 +26,19 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 }
 
 //sysnb	gettimeofday(tp *Timeval) (sec int64, usec int32, err error)
-func Gettimeofday(tv *Timeval) (err error) {
+func Gettimeofday(tv *Timeval) error {
 	// The tv passed to gettimeofday must be non-nil
 	// but is otherwise unused. The answers come back
 	// in the two registers.
 	sec, usec, err := gettimeofday(tv)
+	if err != nil {
+		return err
+	}
+	if sec != 0 || usec != 0 {
 		tv.Sec = sec
 		tv.Usec = usec
-	return err
+	}
+	return nil
 }
 
 func SetKevent(k *Kevent_t, fd, mode, flags int) {

src/syscall/syscall_darwin_test.go

+// Copyright 2016 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
+// +build amd64 386 arm arm64
+
+package syscall_test
+
+import (
+	"syscall"
+	"testing"
+)
+
+func TestDarwinGettimeofday(t *testing.T) {
+	tv := &syscall.Timeval{}
+	if err := syscall.Gettimeofday(tv); err != nil {
+		t.Fatal(err)
+	}
+	if tv.Sec == 0 && tv.Usec == 0 {
+		t.Fatal("Sec and Usec both zero")
+	}
+}