[release-branch.go1.12-security] go1.12.10

Change-Id: I64d76a35ad113110cb83117c6ce5d4d923d93c93
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/558789
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

VERSION

@@ -0,0 +1 @@
+go1.12.10

doc/cmd.html

@@ -18,10 +18,8 @@ underlying binary with arguments appropriate to package-level processing.
 
 <p>
 The programs can also be run as stand-alone binaries, with unmodified arguments,
-using the go <code>tool</code> subcommand, such as <code>go tool vet</code>.
-This style of invocation allows, for instance, checking a single source file
-rather than an entire package: <code>go tool vet myprogram.go</code> as
-compared to <code>go vet mypackage</code>.
+using the go <code>tool</code> subcommand, such as <code>go tool cgo</code>.
+For most commands this is mainly useful for debugging.
 Some of the commands, such as <code>pprof</code>, are accessible only through
 the go <code>tool</code> subcommand.
 </p>
@@ -76,7 +74,7 @@ and rewrites them to use newer ones.</td>
 </tr>
 
 <tr>
-<td><a href="/cmd/go/">fmt</a></td>
+<td><a href="/cmd/gofmt/">fmt</a></td>
 <td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
 <td>Fmt formats Go packages, it is also available as an independent <a href="/cmd/gofmt/">
 gofmt</a> command with more general options.</td>

doc/contrib.html

@@ -34,6 +34,7 @@ We encourage all Go users to subscribe to
 <p>A <a href="/doc/devel/release.html">summary</a> of the changes between Go releases. Notes for the major releases:</p>
 
 <ul>
+	<li><a href="/doc/go1.12">Go 1.12</a> <small>(February 2019)</small></li>
 	<li><a href="/doc/go1.11">Go 1.11</a> <small>(August 2018)</small></li>
 	<li><a href="/doc/go1.10">Go 1.10</a> <small>(February 2018)</small></li>
 	<li><a href="/doc/go1.9">Go 1.9</a> <small>(August 2017)</small></li>

doc/contribute.html

@@ -46,7 +46,8 @@ CLA (Contributor License Agreement).
 <li>
 <b>Step 2</b>: Configure authentication credentials for the Go Git repository.
 Visit <a href="https://go.googlesource.com/">go.googlesource.com</a>, click
-on "Generate Password" (top right), and follow the instructions.
+on the gear icon (top right), then on "Obtain password", and follow the
+instructions.
 </li>
 <li>
 <b>Step 3</b>: Register for Gerrit, the code review tool used by the Go team,

doc/devel/release.html

@@ -23,6 +23,88 @@ in supported releases as needed by issuing minor revisions
 (for example, Go 1.6.1, Go 1.6.2, and so on).
 </p>
 
+<h2 id="go1.12">go1.12 (released 2019/02/25)</h2>
+
+<p>
+Go 1.12 is a major release of Go.
+Read the <a href="/doc/go1.12">Go 1.12 Release Notes</a> for more information.
+</p>
+
+<h3 id="go1.12.minor">Minor revisions</h3>
+
+<p>
+go1.12.1 (released 2019/03/14) includes fixes to cgo, the compiler, the go
+command, and the <code>fmt</code>, <code>net/smtp</code>, <code>os</code>,
+<code>path/filepath</code>, <code>sync</code>, and <code>text/template</code>
+packages. See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.1">Go
+1.12.1 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.12.2 (released 2019/04/05) includes fixes to the compiler, the go
+command, the runtime, and the <code>doc</code>, <code>net</code>,
+<code>net/http/httputil</code>, and <code>os</code> packages. See the
+<a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.2">Go
+1.12.2 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.12.3 (released 2019/04/08) was accidentally released without its
+intended fix. It is identical to go1.12.2, except for its version
+number. The intended fix is in go1.12.4.
+</p>
+
+<p>
+go1.12.4 (released 2019/04/11) fixes an issue where using the prebuilt binary
+releases on older versions of GNU/Linux
+<a href="https://golang.org/issues/31293">led to failures</a>
+when linking programs that used cgo.
+Only Linux users who hit this issue need to update.
+</p>
+
+<p>
+go1.12.5 (released 2019/05/06) includes fixes to the compiler, the linker,
+the go command, the runtime, and the <code>os</code> package. See the
+<a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.5">Go
+1.12.5 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.12.6 (released 2019/06/11) includes fixes to the compiler, the linker,
+the go command, and the <code>crypto/x509</code>, <code>net/http</code>, and
+<code>os</code> packages. See the
+<a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.6">Go
+1.12.6 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.12.7 (released 2019/07/08) includes fixes to cgo, the compiler,
+and the linker.
+See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.7">Go
+1.12.7 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.12.8 (released 2019/08/13) includes security fixes to the
+<code>net/http</code> and <code>net/url</code> packages.
+See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.8">Go
+1.12.8 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.12.9 (released 2019/08/15) includes fixes to the linker,
+and the <code>os</code> and <code>math/big</code> packages.
+See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.9+label%3ACherryPickApproved">Go
+1.12.9 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.12.10 (released 2019/09/25) includes security fixes to the
+<code>net/http</code> and <code>net/textproto</code> packages.
+See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.10">Go
+1.12.10 milestone</a> on our issue tracker for details.
+</p>
+
 <h2 id="go1.11">go1.11 (released 2018/08/24)</h2>
 
 <p>
@@ -66,6 +148,67 @@ See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.4+labe
 1.11.4 milestone</a> on our issue tracker for details.
 </p>
 
+<p>
+go1.11.5 (released 2019/01/23) includes a security fix to the
+<code>crypto/elliptic</code> package.  See
+the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.5">Go
+1.11.5 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.11.6 (released 2019/03/14) includes fixes to cgo, the compiler, linker,
+runtime, go command, and the <code>crypto/x509</code>, <code>encoding/json</code>,
+<code>net</code>, and <code>net/url</code> packages. See the
+<a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.6">Go
+1.11.6 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.11.7 (released 2019/04/05) includes fixes to the runtime and the
+<code>net</code> packages. See the
+<a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.7">Go
+1.11.7 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.11.8 (released 2019/04/08) was accidentally released without its
+intended fix. It is identical to go1.11.7, except for its version
+number. The intended fix is in go1.11.9.
+</p>
+
+<p>
+go1.11.9 (released 2019/04/11) fixes an issue where using the prebuilt binary
+releases on older versions of GNU/Linux
+<a href="https://golang.org/issues/31293">led to failures</a>
+when linking programs that used cgo.
+Only Linux users who hit this issue need to update.
+</p>
+
+<p>
+go1.11.10 (released 2019/05/06) includes fixes to the runtime and the linker.
+See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.10">Go
+1.11.10 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.11.11 (released 2019/06/11) includes a fix to the <code>crypto/x509</code> package.
+See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.11">Go
+1.11.11 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.11.12 (released 2019/07/08) includes fixes to the compiler and the linker.
+See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.12">Go
+1.11.12 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.11.13 (released 2019/08/13) includes security fixes to the
+<code>net/http</code> and <code>net/url</code> packages.
+See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.13">Go
+1.11.13 milestone</a> on our issue tracker for details.
+</p>
+
 <h2 id="go1.10">go1.10 (released 2018/02/16)</h2>
 
 <p>
@@ -131,6 +274,13 @@ See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.10.7+labe
 Go 1.10.7 milestone</a> on our issue tracker for details.
 </p>
 
+<p>
+go1.10.8 (released 2019/01/23) includes a security fix to the
+<code>crypto/elliptic</code> package.  See
+the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.10.8">Go
+1.10.8 milestone</a> on our issue tracker for details.
+</p>
+
 <h2 id="go1.9">go1.9 (released 2017/08/24)</h2>
 
 <p>

doc/go1.12.html

@@ -15,14 +15,7 @@ Do not send CLs removing the interior tags from such phrases.
   ul li { margin: 0.5em 0; }
 </style>
 
-<h2 id="introduction">DRAFT RELEASE NOTES - Introduction to Go 1.12</h2>
-
-<p>
-  <strong>
-    Go 1.12 is not yet released. These are work-in-progress
-    release notes. Go 1.12 is expected to be released in February 2019.
-  </strong>
-</p>
+<h2 id="introduction">Introduction to Go 1.12</h2>
 
 <p>
   The latest Go release, version 1.12, arrives six months after <a href="go1.11">Go 1.11</a>.
@@ -87,6 +80,10 @@ Do not send CLs removing the interior tags from such phrases.
   checks for private API usage. Since it is considered private,
   <code>syscall.Getdirentries</code> now always fails with
   <code>ENOSYS</code> on iOS.
+  Additionally, <a href="/pkg/syscall/#Setrlimit"><code>syscall.Setrlimit</code></a>
+  reports <code>invalid</code> <code>argument</code> in places where it historically
+  succeeded. These consequences are not specific to Go and users should expect
+  behavioral parity with <code>libSystem</code>'s implementation going forward.
 </p>
 
 <h2 id="tools">Tools</h2>
@@ -109,7 +106,7 @@ Do not send CLs removing the interior tags from such phrases.
   is no longer available with <code>go vet</code>. Checking for
   variable shadowing may now be done using
 <pre>
-go install golang.org/x/tools/go/analysis/passes/shadow/cmd/shadow
+go get -u golang.org/x/tools/go/analysis/passes/shadow/cmd/shadow
 go vet -vettool=$(which shadow)
 </pre>
 </p>
@@ -121,7 +118,7 @@ The Go tour is no longer included in the main binary distribution. To
 run the tour locally, instead of running <code>go</code> <code>tool</code> <code>tour</code>,
 manually install it:
 <pre>
-go install golang.org/x/tour
+go get -u golang.org/x/tour
 tour
 </pre>
 </p>
@@ -192,6 +189,17 @@ tour
   that build fails.
 </p>
 
+<p><!-- CL 147282, 147281 -->
+  This changed use of the <code>go</code> directive means that if you
+  use Go 1.12 to build a module, thus recording <code>go 1.12</code>
+  in the <code>go.mod</code> file, you will get an error when
+  attempting to build the same module with Go 1.11 through Go 1.11.3.
+  Go 1.11.4 or later will work fine, as will releases older than Go 1.11.
+  If you must use Go 1.11 through 1.11.3, you can avoid the problem by
+  setting the language version to 1.11, using the Go 1.12 go tool,
+  via <code>go mod edit -go=1.11</code>.
+</p>
+
 <p><!-- CL 152739 -->
   When an import cannot be resolved using the active modules,
   the <code>go</code> command will now try to use the modules mentioned in the
@@ -303,7 +311,9 @@ for {
 <p>
   In Go 1.12, <code>godoc</code> no longer has a command-line interface and
   is only a web server. Users should use <code>go</code> <code>doc</code>
-  for command-line help output instead.
+  for command-line help output instead. Go 1.12 is the last release that will
+  include the <code>godoc</code> webserver; in Go 1.13 it will be available
+  via <code>go</code> <code>get</code>.
 </p>
 
 <p><!-- CL 141977 -->
@@ -493,8 +503,11 @@ for {
 <dl id="crypto/rc4"><dt><a href="/pkg/crypto/rc4/">crypto/rc4</a></dt>
   <dd>
     <p><!-- CL 130397 -->
-      This release removes the optimized assembly implementations. RC4 is insecure
-      and should only be used for compatibility with legacy systems.
+      This release removes the assembly implementations, leaving only
+      the pure Go version. The Go compiler generates code that is
+      either slightly better or slightly worse, depending on the exact
+      CPU. RC4 is insecure and should only be used for compatibility
+      with legacy systems.
     </p>
 
 </dl><!-- crypto/rc4 -->
@@ -602,17 +615,6 @@ for {
 
 </dl><!-- io -->
 
-<dl id="lib/time"><dt><a href="/pkg/lib/time/">lib/time</a></dt>
-  <dd>
-    <p><!-- CL 151299 -->
-      The time zone database in <code>$GOROOT/lib/time/zoneinfo.zip</code>
-      has been updated to version 2018i. Note that this ZIP file is
-      only used if a time zone database is not provided by the operating
-      system.
-    </p>
-
-</dl><!-- lib/time -->
-
 <dl id="math"><dt><a href="/pkg/math/">math</a></dt>
   <dd>
     <p><!-- CL 153059 -->
@@ -689,6 +691,20 @@ for {
 
 </dl><!-- net/http -->
 
+<dl id="net/url"><dt><a href="/pkg/net/url/">net/url</a></dt>
+  <dd>
+    <p><!-- CL 159157, CL 160178 -->
+      <a href="/pkg/net/url/#Parse"><code>Parse</code></a>,
+      <a href="/pkg/net/url/#ParseRequestURI"><code>ParseRequestURI</code></a>,
+      and
+      <a href="/pkg/net/url/#URL.Parse"><code>URL.Parse</code></a>
+      now return an
+      error for URLs containing ASCII control characters, which includes NULL,
+      tab, and newlines.
+    </p>
+
+</dl><!-- net/url -->
+
 <dl id="net/http/httputil"><dt><a href="/pkg/net/http/httputil/">net/http/httputil</a></dt>
   <dd>
     <p><!-- CL 146437 -->
@@ -779,7 +795,7 @@ for {
       A new <a href="/pkg/runtime/debug/#BuildInfo"><code>BuildInfo</code></a> type
       exposes the build information read from the running binary, available only in
       binaries built with module support. This includes the main package path, main
-      module information, and the module dependencies. This type is given though the
+      module information, and the module dependencies. This type is given through the
       <a href="/pkg/runtime/debug/#ReadBuildInfo"><code>ReadBuildInfo</code></a> function
       on <a href="/pkg/runtime/debug/#BuildInfo"><code>BuildInfo</code></a>.
     </p>
@@ -912,6 +928,17 @@ for {
     </p>
 </dl><!-- text/template -->
 
+<dl id="time"><dt><a href="/pkg/time/">time</a></dt>
+  <dd>
+    <p><!-- CL 151299 -->
+      The time zone database in <code>$GOROOT/lib/time/zoneinfo.zip</code>
+      has been updated to version 2018i. Note that this ZIP file is
+      only used if a time zone database is not provided by the operating
+      system.
+    </p>
+
+</dl><!-- time -->
+
 <dl id="unsafe"><dt><a href="/pkg/unsafe/">unsafe</a></dt>
   <dd>
     <p><!-- CL 146058 -->

doc/install-source.html

@@ -349,15 +349,7 @@ provides <b>essential setup instructions</b> for using the Go tools.
 <p>
 The source code for several Go tools (including <a href="/cmd/godoc/">godoc</a>)
 is kept in <a href="https://golang.org/x/tools">the go.tools repository</a>.
-To install all of them, run the <code>go</code> <code>get</code> command:
-</p>
-
-<pre>
-$ go get golang.org/x/tools/cmd/...
-</pre>
-
-<p>
-Or if you just want to install a specific command (<code>godoc</code> in this case):
+To install one of the tools (<code>godoc</code> in this case):
 </p>
 
 <pre>
@@ -374,16 +366,6 @@ You must also have a workspace (<code>GOPATH</code>) set up;
 see <a href="/doc/code.html">How to Write Go Code</a> for the details.
 </p>
 
-<p>
-<b>Note</b>: The <code>go</code> command will install the <code>godoc</code>
-binary to <code>$GOROOT/bin</code> (or <code>$GOBIN</code>) and the
-<code>cover</code> and <code>vet</code> binaries to
-<code>$GOROOT/pkg/tool/$GOOS_$GOARCH</code>.
-You can access the latter commands with
-"<code>go</code> <code>tool</code> <code>cover</code>" and
-"<code>go</code> <code>tool</code> <code>vet</code>".
-</p>
-
 <h2 id="community">Community resources</h2>
 
 <p>

misc/cgo/test/cgo_test.go

@@ -95,6 +95,7 @@ func Test26213(t *testing.T)                 { test26213(t) }
 func Test27660(t *testing.T)                 { test27660(t) }
 func Test28896(t *testing.T)                 { test28896(t) }
 func Test30065(t *testing.T)                 { test30065(t) }
+func Test32579(t *testing.T)                 { test32579(t) }
 
 func BenchmarkCgoCall(b *testing.B)  { benchCgoCall(b) }
 func BenchmarkGoString(b *testing.B) { benchGoString(b) }

misc/cgo/test/issue32579.go

@@ -0,0 +1,22 @@
+// 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 cgotest
+
+// #include <string.h>
+// typedef struct S32579 { unsigned char data[1]; } S32579;
+import "C"
+
+import (
+	"testing"
+	"unsafe"
+)
+
+func test32579(t *testing.T) {
+	var s [1]C.struct_S32579
+	C.memset(unsafe.Pointer(&s[0].data[0]), 1, 1)
+	if s[0].data[0] != 1 {
+		t.Errorf("&s[0].data[0] failed: got %d, want %d", s[0].data[0], 1)
+	}
+}

misc/cgo/test/testdata/issue30527.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.
+
+// Issue 30527: function call rewriting casts untyped
+// constants to int because of ":=" usage.
+
+package cgotest
+
+import "cgotest/issue30527"
+
+func issue30527G() {
+	issue30527.G(nil)
+}

misc/cgo/test/testdata/issue30527/a.go

@@ -0,0 +1,19 @@
+// 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 issue30527
+
+import "math"
+
+/*
+#include <inttypes.h>
+
+static void issue30527F(char **p, uint64_t mod, uint32_t unused) {}
+*/
+import "C"
+
+func G(p **C.char) {
+	C.issue30527F(p, math.MaxUint64, 1)
+	C.issue30527F(p, 1<<64-1, Z)
+}

misc/cgo/test/testdata/issue30527/b.go

@@ -0,0 +1,11 @@
+// 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 issue30527
+
+const (
+	X = 1 << iota
+	Y
+	Z
+)

misc/cgo/testshared/shared_test.go

@@ -917,3 +917,10 @@ func TestTestInstalledShared(t *testing.T) {
 func TestGeneratedMethod(t *testing.T) {
 	goCmd(t, "install", "-buildmode=shared", "-linkshared", "issue25065")
 }
+
+// Test use of shared library struct with generated hash function.
+// Issue 30768.
+func TestGeneratedHash(t *testing.T) {
+	goCmd(nil, "install", "-buildmode=shared", "-linkshared", "issue30768/issue30768lib")
+	goCmd(nil, "test", "-linkshared", "issue30768")
+}

misc/cgo/testshared/src/issue30768/issue30768lib/lib.go

@@ -0,0 +1,11 @@
+// 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 issue30768lib
+
+// S is a struct that requires a generated hash function.
+type S struct {
+	A string
+	B int
+}

misc/cgo/testshared/src/issue30768/x_test.go

@@ -0,0 +1,22 @@
+// 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 issue30768_test
+
+import (
+	"testing"
+
+	"issue30768/issue30768lib"
+)
+
+type s struct {
+	s issue30768lib.S
+}
+
+func Test30768(t *testing.T) {
+	// Calling t.Log will convert S to an empty interface,
+	// which will force a reference to the generated hash function,
+	// defined in the shared library.
+	t.Log(s{})
+}

src/cmd/asm/internal/asm/testdata/arm64.s

@@ -261,6 +261,18 @@ TEXT	foo(SB), DUPOK|NOSPLIT, $-8
 	ORRW	$0x1b000, R2, R3                    // ORRW	$110592, R2, R3                 // 1b0096523b00a07243001b2a
 	TSTW	$0x500000, R1                       // TSTW	$5242880, R1                    // 1b0aa0523f001b6a
 	TSTW	$0xff00ff, R1                       // TSTW	$16711935, R1                   // 3f9c0072
+	TSTW	$0x60060, R5                        // TSTW	$393312, R5                     // 1b0c8052db00a072bf001b6a
+	TSTW	$0x6006000060060, R5                // TSTW	$1689262177517664, R5           // 1b0c8052db00a072bf001b6a
+	ANDW	$0x6006000060060, R5                // ANDW	$1689262177517664, R5           // 1b0c8052db00a072a5001b0a
+	ANDSW	$0x6006000060060, R5                // ANDSW	$1689262177517664, R5           // 1b0c8052db00a072a5001b6a
+	EORW	$0x6006000060060, R5                // EORW	$1689262177517664, R5           // 1b0c8052db00a072a5001b4a
+	ORRW	$0x6006000060060, R5                // ORRW	$1689262177517664, R5           // 1b0c8052db00a072a5001b2a
+	BICW	$0x6006000060060, R5                // BICW	$1689262177517664, R5           // 1b0c8052db00a072a5003b0a
+	EONW	$0x6006000060060, R5                // EONW	$1689262177517664, R5           // 1b0c8052db00a072a5003b4a
+	ORNW	$0x6006000060060, R5                // ORNW	$1689262177517664, R5           // 1b0c8052db00a072a5003b2a
+	BICSW	$0x6006000060060, R5                // BICSW	$1689262177517664, R5           // 1b0c8052db00a072a5003b6a
+	ADDW	$0x60060, R2                        // ADDW	$393312, R2                     // 4280011142804111
+	CMPW	$0x60060, R2                        // CMPW	$393312, R2                     // 1b0c8052db00a0725f001b6b
 
 	AND	$8, R0, RSP // 1f007d92
 	ORR	$8, R0, RSP // 1f007db2

src/cmd/cgo/ast.go

@@ -200,18 +200,6 @@ func (f *File) saveExprs(x interface{}, context astContext) {
 		}
 	case *ast.CallExpr:
 		f.saveCall(x, context)
-	case *ast.GenDecl:
-		if x.Tok == token.CONST {
-			for _, spec := range x.Specs {
-				vs := spec.(*ast.ValueSpec)
-				if vs.Type == nil {
-					for _, name := range spec.(*ast.ValueSpec).Names {
-						consts[name.Name] = true
-					}
-				}
-			}
-		}
-
 	}
 }
 

src/cmd/cgo/gcc.go

@@ -897,21 +897,16 @@ func (p *Package) rewriteCall(f *File, call *Call) (string, bool) {
 			needsUnsafe = true
 		}
 
-		// Explicitly convert untyped constants to the
-		// parameter type, to avoid a type mismatch.
-		if p.isConst(f, arg) {
-			ptype := p.rewriteUnsafe(param.Go)
+		// Use "var x T = ..." syntax to explicitly convert untyped
+		// constants to the parameter type, to avoid a type mismatch.
+		ptype := p.rewriteUnsafe(param.Go)
+
+		if !p.needsPointerCheck(f, param.Go, args[i]) || param.BadPointer {
 			if ptype != param.Go {
 				needsUnsafe = true
 			}
-			arg = &ast.CallExpr{
-				Fun:  ptype,
-				Args: []ast.Expr{arg},
-			}
-		}
-
-		if !p.needsPointerCheck(f, param.Go, args[i]) {
-			fmt.Fprintf(&sb, "_cgo%d := %s; ", i, gofmtPos(arg, origArg.Pos()))
+			fmt.Fprintf(&sb, "var _cgo%d %s = %s; ", i,
+				gofmtLine(ptype), gofmtPos(arg, origArg.Pos()))
 			continue
 		}
 
@@ -1254,47 +1249,6 @@ func (p *Package) isType(t ast.Expr) bool {
 	return false
 }
 
-// isConst reports whether x is an untyped constant expression.
-func (p *Package) isConst(f *File, x ast.Expr) bool {
-	switch x := x.(type) {
-	case *ast.BasicLit:
-		return true
-	case *ast.SelectorExpr:
-		id, ok := x.X.(*ast.Ident)
-		if !ok || id.Name != "C" {
-			return false
-		}
-		name := f.Name[x.Sel.Name]
-		if name != nil {
-			return name.IsConst()
-		}
-	case *ast.Ident:
-		return x.Name == "nil" ||
-			strings.HasPrefix(x.Name, "_Ciconst_") ||
-			strings.HasPrefix(x.Name, "_Cfconst_") ||
-			strings.HasPrefix(x.Name, "_Csconst_") ||
-			consts[x.Name]
-	case *ast.UnaryExpr:
-		return p.isConst(f, x.X)
-	case *ast.BinaryExpr:
-		return p.isConst(f, x.X) && p.isConst(f, x.Y)
-	case *ast.ParenExpr:
-		return p.isConst(f, x.X)
-	case *ast.CallExpr:
-		// Calling the builtin function complex on two untyped
-		// constants returns an untyped constant.
-		// TODO: It's possible to construct a case that will
-		// erroneously succeed if there is a local function
-		// named "complex", shadowing the builtin, that returns
-		// a numeric type. I can't think of any cases that will
-		// erroneously fail.
-		if id, ok := x.Fun.(*ast.Ident); ok && id.Name == "complex" && len(x.Args) == 2 {
-			return p.isConst(f, x.Args[0]) && p.isConst(f, x.Args[1])
-		}
-	}
-	return false
-}
-
 // isVariable reports whether x is a variable, possibly with field references.
 func (p *Package) isVariable(x ast.Expr) bool {
 	switch x := x.(type) {
@@ -1302,6 +1256,8 @@ func (p *Package) isVariable(x ast.Expr) bool {
 		return true
 	case *ast.SelectorExpr:
 		return p.isVariable(x.X)
+	case *ast.IndexExpr:
+		return true
 	}
 	return false
 }
@@ -2511,13 +2467,16 @@ func (c *typeConv) Type(dtype dwarf.Type, pos token.Pos) *Type {
 			// Treat this typedef as a uintptr.
 			s := *sub
 			s.Go = c.uintptr
+			s.BadPointer = true
 			sub = &s
 			// Make sure we update any previously computed type.
 			if oldType := typedef[name.Name]; oldType != nil {
 				oldType.Go = sub.Go
+				oldType.BadPointer = true
 			}
 		}
 		t.Go = name
+		t.BadPointer = sub.BadPointer
 		if unionWithPointer[sub.Go] {
 			unionWithPointer[t.Go] = true
 		}
@@ -2527,6 +2486,7 @@ func (c *typeConv) Type(dtype dwarf.Type, pos token.Pos) *Type {
 		if oldType == nil {
 			tt := *t
 			tt.Go = sub.Go
+			tt.BadPointer = sub.BadPointer
 			typedef[name.Name] = &tt
 		}
 

src/cmd/cgo/main.go

@@ -71,9 +71,6 @@ type File struct {
 	Edit     *edit.Buffer
 }
 
-// Untyped constants in the current package.
-var consts = make(map[string]bool)
-
 func (f *File) offset(p token.Pos) int {
 	return fset.Position(p).Offset
 }
@@ -154,6 +151,7 @@ type Type struct {
 	Go         ast.Expr
 	EnumValues map[string]int64
 	Typedef    string
+	BadPointer bool
 }
 
 // A FuncType collects information about a function type in both the C and Go worlds.

src/cmd/compile/internal/amd64/galign.go

@@ -24,6 +24,7 @@ func Init(arch *gc.Arch) {
 	arch.ZeroRange = zerorange
 	arch.ZeroAuto = zeroAuto
 	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop
 
 	arch.SSAMarkMoves = ssaMarkMoves
 	arch.SSAGenValue = ssaGenValue

src/cmd/compile/internal/arm/galign.go

@@ -19,6 +19,7 @@ func Init(arch *gc.Arch) {
 	arch.ZeroRange = zerorange
 	arch.ZeroAuto = zeroAuto
 	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop
 
 	arch.SSAMarkMoves = func(s *gc.SSAGenState, b *ssa.Block) {}
 	arch.SSAGenValue = ssaGenValue

src/cmd/compile/internal/arm64/galign.go

@@ -19,6 +19,7 @@ func Init(arch *gc.Arch) {
 	arch.ZeroRange = zerorange
 	arch.ZeroAuto = zeroAuto
 	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop
 
 	arch.SSAMarkMoves = func(s *gc.SSAGenState, b *ssa.Block) {}
 	arch.SSAGenValue = ssaGenValue

src/cmd/compile/internal/gc/dwinl.go

@@ -127,7 +127,7 @@ func assembleInlines(fnsym *obj.LSym, dwVars []*dwarf.Var) dwarf.InlCalls {
 				DeclLine: v.DeclLine,
 				DeclCol:  v.DeclCol,
 			}
-			synthesized := strings.HasPrefix(v.Name, "~r") || canonName == "_"
+			synthesized := strings.HasPrefix(v.Name, "~r") || canonName == "_" || strings.HasPrefix(v.Name, "~b")
 			if idx, found := m[vp]; found {
 				v.ChildIndex = int32(idx)
 				v.IsInAbstract = !synthesized

src/cmd/compile/internal/gc/esc.go

@@ -2105,6 +2105,16 @@ func (e *EscState) escwalkBody(level Level, dst *Node, src *Node, step *EscStep,
 				step.describe(src)
 			}
 			extraloopdepth = modSrcLoopdepth
+			if src.Op == OCONVIFACE {
+				lt := src.Left.Type
+				if !lt.IsInterface() && !isdirectiface(lt) && types.Haspointers(lt) {
+					// We're converting from a non-direct interface type.
+					// The interface will hold a heap copy of the data
+					// (by calling convT2I or friend). Flow the data to heap.
+					// See issue 29353.
+					e.escwalk(level, &e.theSink, src.Left, e.stepWalk(dst, src.Left, "interface-converted", step))
+				}
+			}
 		}
 
 	case ODOT,

src/cmd/compile/internal/gc/go.go

@@ -255,9 +255,10 @@ type Arch struct {
 	Use387    bool // should 386 backend use 387 FP instructions instead of sse2.
 	SoftFloat bool
 
-	PadFrame  func(int64) int64
-	ZeroRange func(*Progs, *obj.Prog, int64, int64, *uint32) *obj.Prog
-	Ginsnop   func(*Progs) *obj.Prog
+	PadFrame     func(int64) int64
+	ZeroRange    func(*Progs, *obj.Prog, int64, int64, *uint32) *obj.Prog
+	Ginsnop      func(*Progs) *obj.Prog
+	Ginsnopdefer func(*Progs) *obj.Prog // special ginsnop for deferreturn
 
 	// SSAMarkMoves marks any MOVXconst ops that need to avoid clobbering flags.
 	SSAMarkMoves func(*SSAGenState, *ssa.Block)

src/cmd/compile/internal/gc/obj.go

@@ -287,7 +287,7 @@ func addGCLocals() {
 			}
 		}
 		if x := s.Func.StackObjects; x != nil {
-			ggloblsym(x, int32(len(x.P)), obj.RODATA|obj.LOCAL)
+			ggloblsym(x, int32(len(x.P)), obj.RODATA|obj.DUPOK)
 		}
 	}
 }

src/cmd/compile/internal/gc/order.go

@@ -1108,10 +1108,10 @@ func (o *Order) expr(n, lhs *Node) *Node {
 		if n.Left.Type.IsInterface() {
 			break
 		}
-		if _, needsaddr := convFuncName(n.Left.Type, n.Type); needsaddr || consttype(n.Left) > 0 {
+		if _, needsaddr := convFuncName(n.Left.Type, n.Type); needsaddr || isStaticCompositeLiteral(n.Left) {
 			// Need a temp if we need to pass the address to the conversion function.
-			// We also process constants here, making a named static global whose
-			// address we can put directly in an interface (see OCONVIFACE case in walk).
+			// We also process static composite literal node here, making a named static global
+			// whose address we can put directly in an interface (see OCONVIFACE case in walk).
 			n.Left = o.addrTemp(n.Left)
 		}
 
@@ -1130,14 +1130,40 @@ func (o *Order) expr(n, lhs *Node) *Node {
 		}
 
 	case OANDAND, OOROR:
-		mark := o.markTemp()
-		n.Left = o.expr(n.Left, nil)
+		// ... = LHS && RHS
+		//
+		// var r bool
+		// r = LHS
+		// if r {       // or !r, for OROR
+		//     r = RHS
+		// }
+		// ... = r
 
-		// Clean temporaries from first branch at beginning of second.
-		// Leave them on the stack so that they can be killed in the outer
-		// context in case the short circuit is taken.
-		n.Right = addinit(n.Right, o.cleanTempNoPop(mark))
-		n.Right = o.exprInPlace(n.Right)
+		r := o.newTemp(n.Type, false)
+
+		// Evaluate left-hand side.
+		lhs := o.expr(n.Left, nil)
+		o.out = append(o.out, typecheck(nod(OAS, r, lhs), ctxStmt))
+
+		// Evaluate right-hand side, save generated code.
+		saveout := o.out
+		o.out = nil
+		t := o.markTemp()
+		rhs := o.expr(n.Right, nil)
+		o.out = append(o.out, typecheck(nod(OAS, r, rhs), ctxStmt))
+		o.cleanTemp(t)
+		gen := o.out
+		o.out = saveout
+
+		// If left-hand side doesn't cause a short-circuit, issue right-hand side.
+		nif := nod(OIF, r, nil)
+		if n.Op == OANDAND {
+			nif.Nbody.Set(gen)
+		} else {
+			nif.Rlist.Set(gen)
+		}
+		o.out = append(o.out, nif)
+		n = r
 
 	case OCALLFUNC,
 		OCALLINTER,

src/cmd/compile/internal/gc/pgen.go

@@ -267,7 +267,7 @@ func compile(fn *Node) {
 					// Also make sure we allocate a linker symbol
 					// for the stack object data, for the same reason.
 					if fn.Func.lsym.Func.StackObjects == nil {
-						fn.Func.lsym.Func.StackObjects = lookup(fmt.Sprintf("%s.stkobj", fn.funcname())).Linksym()
+						fn.Func.lsym.Func.StackObjects = Ctxt.Lookup(fn.Func.lsym.Name + ".stkobj")
 					}
 				}
 			}
@@ -597,8 +597,22 @@ func createDwarfVars(fnsym *obj.LSym, fn *Func, automDecls []*Node) ([]*Node, []
 		typename := dwarf.InfoPrefix + typesymname(n.Type)
 		decls = append(decls, n)
 		abbrev := dwarf.DW_ABRV_AUTO_LOCLIST
+		isReturnValue := (n.Class() == PPARAMOUT)
 		if n.Class() == PPARAM || n.Class() == PPARAMOUT {
 			abbrev = dwarf.DW_ABRV_PARAM_LOCLIST
+		} else if n.Class() == PAUTOHEAP {
+			// If dcl in question has been promoted to heap, do a bit
+			// of extra work to recover original class (auto or param);
+			// see issue 30908. This insures that we get the proper
+			// signature in the abstract function DIE, but leaves a
+			// misleading location for the param (we want pointer-to-heap
+			// and not stack).
+			// TODO(thanm): generate a better location expression
+			stackcopy := n.Name.Param.Stackcopy
+			if stackcopy != nil && (stackcopy.Class() == PPARAM || stackcopy.Class() == PPARAMOUT) {
+				abbrev = dwarf.DW_ABRV_PARAM_LOCLIST
+				isReturnValue = (stackcopy.Class() == PPARAMOUT)
+			}
 		}
 		inlIndex := 0
 		if genDwarfInline > 1 {
@@ -612,7 +626,7 @@ func createDwarfVars(fnsym *obj.LSym, fn *Func, automDecls []*Node) ([]*Node, []
 		declpos := Ctxt.InnermostPos(n.Pos)
 		vars = append(vars, &dwarf.Var{
 			Name:          n.Sym.Name,
-			IsReturnValue: n.Class() == PPARAMOUT,
+			IsReturnValue: isReturnValue,
 			Abbrev:        abbrev,
 			StackOffset:   int32(n.Xoffset),
 			Type:          Ctxt.Lookup(typename),

src/cmd/compile/internal/gc/sinit.go

@@ -555,6 +555,13 @@ const (
 	inNonInitFunction
 )
 
+func (c initContext) String() string {
+	if c == inInitFunction {
+		return "inInitFunction"
+	}
+	return "inNonInitFunction"
+}
+
 // from here down is the walk analysis
 // of composite literals.
 // most of the work is to generate
@@ -913,7 +920,13 @@ func slicelit(ctxt initContext, n *Node, var_ *Node, init *Nodes) {
 			break
 
 		case OARRAYLIT, OSTRUCTLIT:
-			fixedlit(ctxt, initKindDynamic, value, a, init)
+			k := initKindDynamic
+			if vstat == nil {
+				// Generate both static and dynamic initializations.
+				// See issue #31987.
+				k = initKindLocalCode
+			}
+			fixedlit(ctxt, k, value, a, init)
 			continue
 		}
 

src/cmd/compile/internal/gc/ssa.go

@@ -993,26 +993,32 @@ func (s *state) stmt(n *Node) {
 		s.assign(n.Left, r, deref, skip)
 
 	case OIF:
-		bThen := s.f.NewBlock(ssa.BlockPlain)
 		bEnd := s.f.NewBlock(ssa.BlockPlain)
-		var bElse *ssa.Block
 		var likely int8
 		if n.Likely() {
 			likely = 1
 		}
+		var bThen *ssa.Block
+		if n.Nbody.Len() != 0 {
+			bThen = s.f.NewBlock(ssa.BlockPlain)
+		} else {
+			bThen = bEnd
+		}
+		var bElse *ssa.Block
 		if n.Rlist.Len() != 0 {
 			bElse = s.f.NewBlock(ssa.BlockPlain)
-			s.condBranch(n.Left, bThen, bElse, likely)
 		} else {
-			s.condBranch(n.Left, bThen, bEnd, likely)
+			bElse = bEnd
 		}
+		s.condBranch(n.Left, bThen, bElse, likely)
 
-		s.startBlock(bThen)
-		s.stmtList(n.Nbody)
-		if b := s.endBlock(); b != nil {
-			b.AddEdgeTo(bEnd)
+		if n.Nbody.Len() != 0 {
+			s.startBlock(bThen)
+			s.stmtList(n.Nbody)
+			if b := s.endBlock(); b != nil {
+				b.AddEdgeTo(bEnd)
+			}
 		}
-
 		if n.Rlist.Len() != 0 {
 			s.startBlock(bElse)
 			s.stmtList(n.Rlist)
@@ -5597,7 +5603,7 @@ func (s *SSAGenState) PrepareCall(v *ssa.Value) {
 		// insert an actual hardware NOP that will have the right line number.
 		// This is different from obj.ANOP, which is a virtual no-op
 		// that doesn't make it into the instruction stream.
-		thearch.Ginsnop(s.pp)
+		thearch.Ginsnopdefer(s.pp)
 	}
 
 	if sym, ok := v.Aux.(*obj.LSym); ok {

src/cmd/compile/internal/mips/galign.go

@@ -22,6 +22,7 @@ func Init(arch *gc.Arch) {
 	arch.ZeroRange = zerorange
 	arch.ZeroAuto = zeroAuto
 	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop
 	arch.SSAMarkMoves = func(s *gc.SSAGenState, b *ssa.Block) {}
 	arch.SSAGenValue = ssaGenValue
 	arch.SSAGenBlock = ssaGenBlock

src/cmd/compile/internal/mips64/galign.go

@@ -22,6 +22,7 @@ func Init(arch *gc.Arch) {
 	arch.ZeroRange = zerorange
 	arch.ZeroAuto = zeroAuto
 	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop
 
 	arch.SSAMarkMoves = func(s *gc.SSAGenState, b *ssa.Block) {}
 	arch.SSAGenValue = ssaGenValue

src/cmd/compile/internal/ppc64/galign.go

@@ -20,7 +20,8 @@ func Init(arch *gc.Arch) {
 
 	arch.ZeroRange = zerorange
 	arch.ZeroAuto = zeroAuto
-	arch.Ginsnop = ginsnop2
+	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop2
 
 	arch.SSAMarkMoves = ssaMarkMoves
 	arch.SSAGenValue = ssaGenValue

src/cmd/compile/internal/s390x/galign.go

@@ -17,6 +17,7 @@ func Init(arch *gc.Arch) {
 	arch.ZeroRange = zerorange
 	arch.ZeroAuto = zeroAuto
 	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop
 
 	arch.SSAMarkMoves = ssaMarkMoves
 	arch.SSAGenValue = ssaGenValue

src/cmd/compile/internal/ssa/gen/AMD64.rules

@@ -1597,13 +1597,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORL <v.Type> (SHLLconst <v.Type> [j0] (MOVWload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j0] (MOVWload [i0] {s} p mem)) y)
 
 (ORQ
     s1:(SHLQconst [j1] x1:(MOVBload [i1] {s} p mem))
@@ -1618,13 +1618,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVWload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVWload [i0] {s} p mem)) y)
 
 (ORQ
     s1:(SHLQconst [j1] x1:(MOVWload [i1] {s} p mem))
@@ -1639,13 +1639,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVLload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVLload [i0] {s} p mem)) y)
 
 // Little-endian indexed loads
 
@@ -1722,13 +1722,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORL <v.Type> (SHLLconst <v.Type> [j0] (MOVWloadidx1 [i0] {s} p idx mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j0] (MOVWloadidx1 [i0] {s} p idx mem)) y)
 
 (ORQ
     s1:(SHLQconst [j1] x1:(MOVBloadidx1 [i1] {s} p idx mem))
@@ -1743,13 +1743,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVWloadidx1 [i0] {s} p idx mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVWloadidx1 [i0] {s} p idx mem)) y)
 
 (ORQ
     s1:(SHLQconst [j1] x1:(MOVWloadidx1 [i1] {s} p idx mem))
@@ -1764,13 +1764,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVLloadidx1 [i0] {s} p idx mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVLloadidx1 [i0] {s} p idx mem)) y)
 
 // Big-endian loads
 
@@ -1864,13 +1864,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORL <v.Type> (SHLLconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWload [i0] {s} p mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWload [i0] {s} p mem))) y)
 
 (ORQ
     s0:(SHLQconst [j0] x0:(MOVBload [i0] {s} p mem))
@@ -1885,13 +1885,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWload [i0] {s} p mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWload [i0] {s} p mem))) y)
 
 (ORQ
     s0:(SHLQconst [j0] r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p mem)))
@@ -1908,7 +1908,7 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(r0)
@@ -1916,7 +1916,7 @@
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (BSWAPL <typ.UInt32> (MOVLload [i0] {s} p mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (BSWAPL <typ.UInt32> (MOVLload [i0] {s} p mem))) y)
 
 // Big-endian indexed loads
 
@@ -2010,13 +2010,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORL <v.Type> (SHLLconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWloadidx1 [i0] {s} p idx mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWloadidx1 [i0] {s} p idx mem))) y)
 
 (ORQ
     s0:(SHLQconst [j0] x0:(MOVBloadidx1 [i0] {s} p idx mem))
@@ -2031,13 +2031,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWloadidx1 [i0] {s} p idx mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWloadidx1 [i0] {s} p idx mem))) y)
 
 (ORQ
     s0:(SHLQconst [j0] r0:(ROLWconst [8] x0:(MOVWloadidx1 [i0] {s} p idx mem)))
@@ -2054,7 +2054,7 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(r0)
@@ -2062,7 +2062,7 @@
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (BSWAPL <typ.UInt32> (MOVLloadidx1 [i0] {s} p idx mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (BSWAPL <typ.UInt32> (MOVLloadidx1 [i0] {s} p idx mem))) y)
 
 // Combine 2 byte stores + shift into rolw 8 + word store
 (MOVBstore [i] {s} p w

src/cmd/compile/internal/ssa/gen/S390X.rules

@@ -1480,13 +1480,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORW <v.Type> (SLWconst <v.Type> [j1] (MOVHZload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORW <v.Type> (SLWconst <v.Type> [j1] (MOVHZload [i0] {s} p mem)) y)
 
 (OR
     s0:(SLDconst [j0] x0:(MOVBZload [i0] {s} p mem))
@@ -1501,13 +1501,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (OR <v.Type> (SLDconst <v.Type> [j1] (MOVHZload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (OR <v.Type> (SLDconst <v.Type> [j1] (MOVHZload [i0] {s} p mem)) y)
 
 (OR
     s0:(SLDconst [j0] x0:(MOVHZload [i0] {s} p mem))
@@ -1522,13 +1522,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (OR <v.Type> (SLDconst <v.Type> [j1] (MOVWZload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (OR <v.Type> (SLDconst <v.Type> [j1] (MOVWZload [i0] {s} p mem)) y)
 
 // Big-endian indexed loads
 
@@ -1610,13 +1610,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORW <v.Type> (SLWconst <v.Type> [j1] (MOVHZloadidx [i0] {s} p idx mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORW <v.Type> (SLWconst <v.Type> [j1] (MOVHZloadidx [i0] {s} p idx mem)) y)
 
 (OR
     s0:(SLDconst [j0] x0:(MOVBZloadidx [i0] {s} p idx mem))
@@ -1631,13 +1631,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (OR <v.Type> (SLDconst <v.Type> [j1] (MOVHZloadidx [i0] {s} p idx mem)) y)
+  -> @mergePoint(b,x0,x1,y) (OR <v.Type> (SLDconst <v.Type> [j1] (MOVHZloadidx [i0] {s} p idx mem)) y)
 
 (OR
     s0:(SLDconst [j0] x0:(MOVHZloadidx [i0] {s} p idx mem))
@@ -1652,13 +1652,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (OR <v.Type> (SLDconst <v.Type> [j1] (MOVWZloadidx [i0] {s} p idx mem)) y)
+  -> @mergePoint(b,x0,x1,y) (OR <v.Type> (SLDconst <v.Type> [j1] (MOVWZloadidx [i0] {s} p idx mem)) y)
 
 // Little-endian loads
 
@@ -1750,13 +1750,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORW <v.Type> (SLWconst <v.Type> [j0] (MOVHZreg (MOVHBRload [i0] {s} p mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORW <v.Type> (SLWconst <v.Type> [j0] (MOVHZreg (MOVHBRload [i0] {s} p mem))) y)
 
 (OR
     s1:(SLDconst [j1] x1:(MOVBZload [i1] {s} p mem))
@@ -1772,13 +1772,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (OR <v.Type> (SLDconst <v.Type> [j0] (MOVHZreg (MOVHBRload [i0] {s} p mem))) y)
+  -> @mergePoint(b,x0,x1,y) (OR <v.Type> (SLDconst <v.Type> [j0] (MOVHZreg (MOVHBRload [i0] {s} p mem))) y)
 
 (OR
     s1:(SLDconst [j1] r1:(MOVHZreg x1:(MOVHBRload [i1] {s} p mem)))
@@ -1795,7 +1795,7 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(r0)
@@ -1803,7 +1803,7 @@
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (OR <v.Type> (SLDconst <v.Type> [j0] (MOVWZreg (MOVWBRload [i0] {s} p mem))) y)
+  -> @mergePoint(b,x0,x1,y) (OR <v.Type> (SLDconst <v.Type> [j0] (MOVWZreg (MOVWBRload [i0] {s} p mem))) y)
 
 // Little-endian indexed loads
 
@@ -1895,13 +1895,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (ORW <v.Type> (SLWconst <v.Type> [j0] (MOVHZreg (MOVHBRloadidx [i0] {s} p idx mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORW <v.Type> (SLWconst <v.Type> [j0] (MOVHZreg (MOVHBRloadidx [i0] {s} p idx mem))) y)
 
 (OR
     s1:(SLDconst [j1] x1:(MOVBZloadidx [i1] {s} p idx mem))
@@ -1917,13 +1917,13 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (OR <v.Type> (SLDconst <v.Type> [j0] (MOVHZreg (MOVHBRloadidx [i0] {s} p idx mem))) y)
+  -> @mergePoint(b,x0,x1,y) (OR <v.Type> (SLDconst <v.Type> [j0] (MOVHZreg (MOVHBRloadidx [i0] {s} p idx mem))) y)
 
 (OR
     s1:(SLDconst [j1] r1:(MOVHZreg x1:(MOVHBRloadidx [i1] {s} p idx mem)))
@@ -1940,7 +1940,7 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
-  && mergePoint(b,x0,x1) != nil
+  && mergePoint(b,x0,x1,y) != nil
   && clobber(x0)
   && clobber(x1)
   && clobber(r0)
@@ -1948,7 +1948,7 @@
   && clobber(s0)
   && clobber(s1)
   && clobber(or)
-  -> @mergePoint(b,x0,x1) (OR <v.Type> (SLDconst <v.Type> [j0] (MOVWZreg (MOVWBRloadidx [i0] {s} p idx mem))) y)
+  -> @mergePoint(b,x0,x1,y) (OR <v.Type> (SLDconst <v.Type> [j0] (MOVWZreg (MOVWBRloadidx [i0] {s} p idx mem))) y)
 
 // Combine stores into store multiples.
 // 32-bit

src/cmd/compile/internal/ssa/prove.go

@@ -549,15 +549,29 @@ func (ft *factsTable) isNonNegative(v *Value) bool {
 		return true
 	}
 
+	var max int64
+	switch v.Type.Size() {
+	case 1:
+		max = math.MaxInt8
+	case 2:
+		max = math.MaxInt16
+	case 4:
+		max = math.MaxInt32
+	case 8:
+		max = math.MaxInt64
+	default:
+		panic("unexpected integer size")
+	}
+
 	// Check if the recorded limits can prove that the value is positive
-	if l, has := ft.limits[v.ID]; has && (l.min >= 0 || l.umax <= math.MaxInt64) {
+	if l, has := ft.limits[v.ID]; has && (l.min >= 0 || l.umax <= uint64(max)) {
 		return true
 	}
 
 	// Check if v = x+delta, and we can use x's limits to prove that it's positive
 	if x, delta := isConstDelta(v); x != nil {
 		if l, has := ft.limits[x.ID]; has {
-			if delta > 0 && l.min >= -delta && l.max <= math.MaxInt64-delta {
+			if delta > 0 && l.min >= -delta && l.max <= max-delta {
 				return true
 			}
 			if delta < 0 && l.min >= -delta {

src/cmd/compile/internal/ssa/regalloc.go

@@ -1220,6 +1220,13 @@ func (s *regAllocState) regalloc(f *Func) {
 					// This forces later liveness analysis to make the
 					// value live at this point.
 					v.SetArg(0, s.makeSpill(a, b))
+				} else if _, ok := a.Aux.(GCNode); ok && vi.rematerializeable {
+					// Rematerializeable value with a gc.Node. This is the address of
+					// a stack object (e.g. an LEAQ). Keep the object live.
+					// Change it to VarLive, which is what plive expects for locals.
+					v.Op = OpVarLive
+					v.SetArgs1(v.Args[1])
+					v.Aux = a.Aux
 				} else {
 					// In-register and rematerializeable values are already live.
 					// These are typically rematerializeable constants like nil,

src/cmd/compile/internal/ssa/rewrite.go

@@ -1141,7 +1141,7 @@ func symIsRO(sym interface{}) bool {
 // read8 reads one byte from the read-only global sym at offset off.
 func read8(sym interface{}, off int64) uint8 {
 	lsym := sym.(*obj.LSym)
-	if off >= int64(len(lsym.P)) {
+	if off >= int64(len(lsym.P)) || off < 0 {
 		// Invalid index into the global sym.
 		// This can happen in dead code, so we don't want to panic.
 		// Just return any value, it will eventually get ignored.
@@ -1154,7 +1154,7 @@ func read8(sym interface{}, off int64) uint8 {
 // read16 reads two bytes from the read-only global sym at offset off.
 func read16(sym interface{}, off int64, bigEndian bool) uint16 {
 	lsym := sym.(*obj.LSym)
-	if off >= int64(len(lsym.P))-1 {
+	if off >= int64(len(lsym.P))-1 || off < 0 {
 		return 0
 	}
 	if bigEndian {
@@ -1167,7 +1167,7 @@ func read16(sym interface{}, off int64, bigEndian bool) uint16 {
 // read32 reads four bytes from the read-only global sym at offset off.
 func read32(sym interface{}, off int64, bigEndian bool) uint32 {
 	lsym := sym.(*obj.LSym)
-	if off >= int64(len(lsym.P))-3 {
+	if off >= int64(len(lsym.P))-3 || off < 0 {
 		return 0
 	}
 	if bigEndian {
@@ -1180,7 +1180,7 @@ func read32(sym interface{}, off int64, bigEndian bool) uint32 {
 // read64 reads eight bytes from the read-only global sym at offset off.
 func read64(sym interface{}, off int64, bigEndian bool) uint64 {
 	lsym := sym.(*obj.LSym)
-	if off >= int64(len(lsym.P))-7 {
+	if off >= int64(len(lsym.P))-7 || off < 0 {
 		return 0
 	}
 	if bigEndian {

src/cmd/compile/internal/ssa/writebarrier.go

@@ -196,6 +196,43 @@ func writebarrier(f *Func) {
 		// and simple store version to bElse
 		memThen := mem
 		memElse := mem
+
+		// If the source of a MoveWB is volatile (will be clobbered by a
+		// function call), we need to copy it to a temporary location, as
+		// marshaling the args of typedmemmove might clobber the value we're
+		// trying to move.
+		// Look for volatile source, copy it to temporary before we emit any
+		// call.
+		// It is unlikely to have more than one of them. Just do a linear
+		// search instead of using a map.
+		type volatileCopy struct {
+			src *Value // address of original volatile value
+			tmp *Value // address of temporary we've copied the volatile value into
+		}
+		var volatiles []volatileCopy
+	copyLoop:
+		for _, w := range stores {
+			if w.Op == OpMoveWB {
+				val := w.Args[1]
+				if isVolatile(val) {
+					for _, c := range volatiles {
+						if val == c.src {
+							continue copyLoop // already copied
+						}
+					}
+
+					t := val.Type.Elem()
+					tmp := f.fe.Auto(w.Pos, t)
+					memThen = bThen.NewValue1A(w.Pos, OpVarDef, types.TypeMem, tmp, memThen)
+					tmpaddr := bThen.NewValue2A(w.Pos, OpLocalAddr, t.PtrTo(), tmp, sp, memThen)
+					siz := t.Size()
+					memThen = bThen.NewValue3I(w.Pos, OpMove, types.TypeMem, siz, tmpaddr, val, memThen)
+					memThen.Aux = t
+					volatiles = append(volatiles, volatileCopy{val, tmpaddr})
+				}
+			}
+		}
+
 		for _, w := range stores {
 			ptr := w.Args[0]
 			pos := w.Pos
@@ -222,11 +259,19 @@ func writebarrier(f *Func) {
 			// then block: emit write barrier call
 			switch w.Op {
 			case OpStoreWB, OpMoveWB, OpZeroWB:
-				volatile := w.Op == OpMoveWB && isVolatile(val)
 				if w.Op == OpStoreWB {
 					memThen = bThen.NewValue3A(pos, OpWB, types.TypeMem, gcWriteBarrier, ptr, val, memThen)
 				} else {
-					memThen = wbcall(pos, bThen, fn, typ, ptr, val, memThen, sp, sb, volatile)
+					srcval := val
+					if w.Op == OpMoveWB && isVolatile(srcval) {
+						for _, c := range volatiles {
+							if srcval == c.src {
+								srcval = c.tmp
+								break
+							}
+						}
+					}
+					memThen = wbcall(pos, bThen, fn, typ, ptr, srcval, memThen, sp, sb)
 				}
 				// Note that we set up a writebarrier function call.
 				f.fe.SetWBPos(pos)
@@ -249,6 +294,12 @@ func writebarrier(f *Func) {
 			}
 		}
 
+		// mark volatile temps dead
+		for _, c := range volatiles {
+			tmpNode := c.tmp.Aux
+			memThen = bThen.NewValue1A(memThen.Pos, OpVarKill, types.TypeMem, tmpNode, memThen)
+		}
+
 		// merge memory
 		// Splice memory Phi into the last memory of the original sequence,
 		// which may be used in subsequent blocks. Other memories in the
@@ -302,25 +353,9 @@ func writebarrier(f *Func) {
 }
 
 // wbcall emits write barrier runtime call in b, returns memory.
-// if valIsVolatile, it moves val into temp space before making the call.
-func wbcall(pos src.XPos, b *Block, fn, typ *obj.LSym, ptr, val, mem, sp, sb *Value, valIsVolatile bool) *Value {
+func wbcall(pos src.XPos, b *Block, fn, typ *obj.LSym, ptr, val, mem, sp, sb *Value) *Value {
 	config := b.Func.Config
 
-	var tmp GCNode
-	if valIsVolatile {
-		// Copy to temp location if the source is volatile (will be clobbered by
-		// a function call). Marshaling the args to typedmemmove might clobber the
-		// value we're trying to move.
-		t := val.Type.Elem()
-		tmp = b.Func.fe.Auto(val.Pos, t)
-		mem = b.NewValue1A(pos, OpVarDef, types.TypeMem, tmp, mem)
-		tmpaddr := b.NewValue2A(pos, OpLocalAddr, t.PtrTo(), tmp, sp, mem)
-		siz := t.Size()
-		mem = b.NewValue3I(pos, OpMove, types.TypeMem, siz, tmpaddr, val, mem)
-		mem.Aux = t
-		val = tmpaddr
-	}
-
 	// put arguments on stack
 	off := config.ctxt.FixedFrameSize()
 
@@ -348,11 +383,6 @@ func wbcall(pos src.XPos, b *Block, fn, typ *obj.LSym, ptr, val, mem, sp, sb *Va
 	// issue call
 	mem = b.NewValue1A(pos, OpStaticCall, types.TypeMem, fn, mem)
 	mem.AuxInt = off - config.ctxt.FixedFrameSize()
-
-	if valIsVolatile {
-		mem = b.NewValue1A(pos, OpVarKill, types.TypeMem, tmp, mem) // mark temp dead
-	}
-
 	return mem
 }
 

src/cmd/compile/internal/wasm/ssa.go

@@ -20,6 +20,7 @@ func Init(arch *gc.Arch) {
 	arch.ZeroRange = zeroRange
 	arch.ZeroAuto = zeroAuto
 	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop
 
 	arch.SSAMarkMoves = ssaMarkMoves
 	arch.SSAGenValue = ssaGenValue

src/cmd/compile/internal/x86/galign.go

@@ -32,6 +32,7 @@ func Init(arch *gc.Arch) {
 	arch.ZeroRange = zerorange
 	arch.ZeroAuto = zeroAuto
 	arch.Ginsnop = ginsnop
+	arch.Ginsnopdefer = ginsnop
 
 	arch.SSAMarkMoves = ssaMarkMoves
 }

src/cmd/go/internal/cache/default.go

@@ -37,7 +37,7 @@ See golang.org to learn more about Go.
 // the first time Default is called.
 func initDefaultCache() {
 	dir := DefaultDir()
-	if dir == "off" || dir == "" {
+	if dir == "off" {
 		if defaultDirErr != nil {
 			base.Fatalf("build cache is required, but could not be located: %v", defaultDirErr)
 		}
@@ -74,7 +74,12 @@ func DefaultDir() string {
 
 	defaultDirOnce.Do(func() {
 		defaultDir = os.Getenv("GOCACHE")
+		if filepath.IsAbs(defaultDir) || defaultDir == "off" {
+			return
+		}
 		if defaultDir != "" {
+			defaultDir = "off"
+			defaultDirErr = fmt.Errorf("GOCACHE is not an absolute path")
 			return
 		}
 

src/cmd/go/internal/get/vcs.go

@@ -424,8 +424,8 @@ func (v *vcsCmd) run1(dir string, cmdline string, keyval []string, verbose bool)
 	cmd.Dir = dir
 	cmd.Env = base.EnvForDir(cmd.Dir, os.Environ())
 	if cfg.BuildX {
-		fmt.Printf("cd %s\n", dir)
-		fmt.Printf("%s %s\n", v.cmd, strings.Join(args, " "))
+		fmt.Fprintf(os.Stderr, "cd %s\n", dir)
+		fmt.Fprintf(os.Stderr, "%s %s\n", v.cmd, strings.Join(args, " "))
 	}
 	out, err := cmd.Output()
 	if err != nil {

src/cmd/go/internal/imports/scan.go

@@ -26,7 +26,7 @@ func ScanDir(dir string, tags map[string]bool) ([]string, []string, error) {
 		// If the directory entry is a symlink, stat it to obtain the info for the
 		// link target instead of the link itself.
 		if info.Mode()&os.ModeSymlink != 0 {
-			info, err = os.Stat(name)
+			info, err = os.Stat(filepath.Join(dir, name))
 			if err != nil {
 				continue // Ignore broken symlinks.
 			}

src/cmd/go/internal/load/pkg.go

@@ -1178,6 +1178,36 @@ var cgoSyscallExclude = map[string]bool{
 
 var foldPath = make(map[string]string)
 
+// DefaultExecName returns the default executable name
+// for a package with the import path importPath.
+//
+// The default executable name is the last element of the import path.
+// In module-aware mode, an additional rule is used. If the last element
+// is a vN path element specifying the major version, then the second last
+// element of the import path is used instead.
+func DefaultExecName(importPath string) string {
+	_, elem := pathpkg.Split(importPath)
+	if cfg.ModulesEnabled {
+		// If this is example.com/mycmd/v2, it's more useful to install it as mycmd than as v2.
+		// See golang.org/issue/24667.
+		isVersion := func(v string) bool {
+			if len(v) < 2 || v[0] != 'v' || v[1] < '1' || '9' < v[1] {
+				return false
+			}
+			for i := 2; i < len(v); i++ {
+				if c := v[i]; c < '0' || '9' < c {
+					return false
+				}
+			}
+			return true
+		}
+		if isVersion(elem) {
+			_, elem = pathpkg.Split(pathpkg.Dir(importPath))
+		}
+	}
+	return elem
+}
+
 // load populates p using information from bp, err, which should
 // be the result of calling build.Context.Import.
 func (p *Package) load(stk *ImportStack, bp *build.Package, err error) {
@@ -1220,7 +1250,7 @@ func (p *Package) load(stk *ImportStack, bp *build.Package, err error) {
 		}
 		_, elem := filepath.Split(p.Dir)
 		if cfg.ModulesEnabled {
-			// NOTE(rsc): Using p.ImportPath instead of p.Dir
+			// NOTE(rsc,dmitshur): Using p.ImportPath instead of p.Dir
 			// makes sure we install a package in the root of a
 			// cached module directory as that package name
 			// not name@v1.2.3.
@@ -1229,26 +1259,9 @@ func (p *Package) load(stk *ImportStack, bp *build.Package, err error) {
 			// even for non-module-enabled code,
 			// but I'm not brave enough to change the
 			// non-module behavior this late in the
-			// release cycle. Maybe for Go 1.12.
+			// release cycle. Can be done for Go 1.13.
 			// See golang.org/issue/26869.
-			_, elem = pathpkg.Split(p.ImportPath)
-
-			// If this is example.com/mycmd/v2, it's more useful to install it as mycmd than as v2.
-			// See golang.org/issue/24667.
-			isVersion := func(v string) bool {
-				if len(v) < 2 || v[0] != 'v' || v[1] < '1' || '9' < v[1] {
-					return false
-				}
-				for i := 2; i < len(v); i++ {
-					if c := v[i]; c < '0' || '9' < c {
-						return false
-					}
-				}
-				return true
-			}
-			if isVersion(elem) {
-				_, elem = pathpkg.Split(pathpkg.Dir(p.ImportPath))
-			}
+			elem = DefaultExecName(p.ImportPath)
 		}
 		full := cfg.BuildContext.GOOS + "_" + cfg.BuildContext.GOARCH + "/" + elem
 		if cfg.BuildContext.GOOS != base.ToolGOOS || cfg.BuildContext.GOARCH != base.ToolGOARCH {

src/cmd/go/internal/load/test.go

@@ -129,6 +129,7 @@ func TestPackagesFor(p *Package, cover *TestCover) (pmain, ptest, pxtest *Packag
 		ptest.Internal.Imports = append(imports, p.Internal.Imports...)
 		ptest.Internal.RawImports = str.StringList(rawTestImports, p.Internal.RawImports)
 		ptest.Internal.ForceLibrary = true
+		ptest.Internal.BuildInfo = ""
 		ptest.Internal.Build = new(build.Package)
 		*ptest.Internal.Build = *p.Internal.Build
 		m := map[string][]token.Position{}
@@ -186,6 +187,7 @@ func TestPackagesFor(p *Package, cover *TestCover) (pmain, ptest, pxtest *Packag
 		},
 		Internal: PackageInternal{
 			Build:      &build.Package{Name: "main"},
+			BuildInfo:  p.Internal.BuildInfo,
 			Asmflags:   p.Internal.Asmflags,
 			Gcflags:    p.Internal.Gcflags,
 			Ldflags:    p.Internal.Ldflags,
@@ -266,17 +268,8 @@ func TestPackagesFor(p *Package, cover *TestCover) (pmain, ptest, pxtest *Packag
 	pmain.Imports = pmain.Imports[:w]
 	pmain.Internal.RawImports = str.StringList(pmain.Imports)
 
-	if ptest != p {
-		// We have made modifications to the package p being tested
-		// and are rebuilding p (as ptest).
-		// Arrange to rebuild all packages q such that
-		// the test depends on q and q depends on p.
-		// This makes sure that q sees the modifications to p.
-		// Strictly speaking, the rebuild is only necessary if the
-		// modifications to p change its export metadata, but
-		// determining that is a bit tricky, so we rebuild always.
-		recompileForTest(pmain, p, ptest, pxtest)
-	}
+	// Replace pmain's transitive dependencies with test copies, as necessary.
+	recompileForTest(pmain, p, ptest, pxtest)
 
 	// Should we apply coverage analysis locally,
 	// only for this package and only for this test?
@@ -323,6 +316,15 @@ Search:
 	return stk
 }
 
+// recompileForTest copies and replaces certain packages in pmain's dependency
+// graph. This is necessary for two reasons. First, if ptest is different than
+// preal, packages that import the package under test should get ptest instead
+// of preal. This is particularly important if pxtest depends on functionality
+// exposed in test sources in ptest. Second, if there is a main package
+// (other than pmain) anywhere, we need to set p.Internal.ForceLibrary and
+// clear p.Internal.BuildInfo in the test copy to prevent link conflicts.
+// This may happen if both -coverpkg and the command line patterns include
+// multiple main packages.
 func recompileForTest(pmain, preal, ptest, pxtest *Package) {
 	// The "test copy" of preal is ptest.
 	// For each package that depends on preal, make a "test copy"
@@ -352,6 +354,8 @@ func recompileForTest(pmain, preal, ptest, pxtest *Package) {
 			copy(p1.Imports, p.Imports)
 			p = p1
 			p.Target = ""
+			p.Internal.BuildInfo = ""
+			p.Internal.ForceLibrary = true
 		}
 
 		// Update p.Internal.Imports to use test copies.
@@ -361,6 +365,13 @@ func recompileForTest(pmain, preal, ptest, pxtest *Package) {
 				p.Internal.Imports[i] = p1
 			}
 		}
+
+		// Don't compile build info from a main package. This can happen
+		// if -coverpkg patterns include main packages, since those packages
+		// are imported by pmain. See golang.org/issue/30907.
+		if p.Internal.BuildInfo != "" && p != pmain {
+			split()
+		}
 	}
 }
 

src/cmd/go/internal/modfetch/coderepo.go

@@ -23,55 +23,99 @@ import (
 type codeRepo struct {
 	modPath string
 
-	code     codehost.Repo
+	// code is the repository containing this module.
+	code codehost.Repo
+	// codeRoot is the import path at the root of code.
 	codeRoot string
-	codeDir  string
+	// codeDir is the directory (relative to root) at which we expect to find the module.
+	// If pathMajor is non-empty and codeRoot is not the full modPath,
+	// then we look in both codeDir and codeDir+modPath
+	codeDir string
 
-	path        string
-	pathPrefix  string
-	pathMajor   string
+	// pathMajor is the suffix of modPath that indicates its major version,
+	// or the empty string if modPath is at major version 0 or 1.
+	//
+	// pathMajor is typically of the form "/vN", but possibly ".vN", or
+	// ".vN-unstable" for modules resolved using gopkg.in.
+	pathMajor string
+	// pathPrefix is the prefix of modPath that excludes pathMajor.
+	// It is used only for logging.
+	pathPrefix string
+
+	// pseudoMajor is the major version prefix to use when generating
+	// pseudo-versions for this module, derived from the module path.
+	//
+	// TODO(golang.org/issue/29262): We can't distinguish v0 from v1 using the
+	// path alone: we have to compute it by examining the tags at a particular
+	// revision.
 	pseudoMajor string
 }
 
-func newCodeRepo(code codehost.Repo, root, path string) (Repo, error) {
-	if !hasPathPrefix(path, root) {
-		return nil, fmt.Errorf("mismatched repo: found %s for %s", root, path)
+// newCodeRepo returns a Repo that reads the source code for the module with the
+// given path, from the repo stored in code, with the root of the repo
+// containing the path given by codeRoot.
+func newCodeRepo(code codehost.Repo, codeRoot, path string) (Repo, error) {
+	if !hasPathPrefix(path, codeRoot) {
+		return nil, fmt.Errorf("mismatched repo: found %s for %s", codeRoot, path)
 	}
 	pathPrefix, pathMajor, ok := module.SplitPathVersion(path)
 	if !ok {
 		return nil, fmt.Errorf("invalid module path %q", path)
 	}
+	if codeRoot == path {
+		pathPrefix = path
+	}
 	pseudoMajor := "v0"
 	if pathMajor != "" {
 		pseudoMajor = pathMajor[1:]
 	}
 
+	// Compute codeDir = bar, the subdirectory within the repo
+	// corresponding to the module root.
+	//
 	// At this point we might have:
-	//	codeRoot = github.com/rsc/foo
 	//	path = github.com/rsc/foo/bar/v2
+	//	codeRoot = github.com/rsc/foo
 	//	pathPrefix = github.com/rsc/foo/bar
 	//	pathMajor = /v2
 	//	pseudoMajor = v2
 	//
-	// Compute codeDir = bar, the subdirectory within the repo
-	// corresponding to the module root.
-	codeDir := strings.Trim(strings.TrimPrefix(pathPrefix, root), "/")
-	if strings.HasPrefix(path, "gopkg.in/") {
-		// But gopkg.in is a special legacy case, in which pathPrefix does not start with codeRoot.
-		// For example we might have:
-		//	codeRoot = gopkg.in/yaml.v2
-		//	pathPrefix = gopkg.in/yaml
-		//	pathMajor = .v2
-		//	pseudoMajor = v2
-		//	codeDir = pathPrefix (because codeRoot is not a prefix of pathPrefix)
-		// Clear codeDir - the module root is the repo root for gopkg.in repos.
-		codeDir = ""
+	// which gives
+	//	codeDir = bar
+	//
+	// We know that pathPrefix is a prefix of path, and codeRoot is a prefix of
+	// path, but codeRoot may or may not be a prefix of pathPrefix, because
+	// codeRoot may be the entire path (in which case codeDir should be empty).
+	// That occurs in two situations.
+	//
+	// One is when a go-import meta tag resolves the complete module path,
+	// including the pathMajor suffix:
+	//	path = nanomsg.org/go/mangos/v2
+	//	codeRoot = nanomsg.org/go/mangos/v2
+	//	pathPrefix = nanomsg.org/go/mangos
+	//	pathMajor = /v2
+	//	pseudoMajor = v2
+	//
+	// The other is similar: for gopkg.in only, the major version is encoded
+	// with a dot rather than a slash, and thus can't be in a subdirectory.
+	//	path = gopkg.in/yaml.v2
+	//	codeRoot = gopkg.in/yaml.v2
+	//	pathPrefix = gopkg.in/yaml
+	//	pathMajor = .v2
+	//	pseudoMajor = v2
+	//
+	codeDir := ""
+	if codeRoot != path {
+		if !hasPathPrefix(pathPrefix, codeRoot) {
+			return nil, fmt.Errorf("repository rooted at %s cannot contain module %s", codeRoot, path)
+		}
+		codeDir = strings.Trim(pathPrefix[len(codeRoot):], "/")
 	}
 
 	r := &codeRepo{
 		modPath:     path,
 		code:        code,
-		codeRoot:    root,
+		codeRoot:    codeRoot,
 		codeDir:     codeDir,
 		pathPrefix:  pathPrefix,
 		pathMajor:   pathMajor,
@@ -149,9 +193,6 @@ func (r *codeRepo) Stat(rev string) (*RevInfo, error) {
 		return r.Latest()
 	}
 	codeRev := r.revToRev(rev)
-	if semver.IsValid(codeRev) && r.codeDir != "" {
-		codeRev = r.codeDir + "/" + codeRev
-	}
 	info, err := r.code.Stat(codeRev)
 	if err != nil {
 		return nil, err
@@ -290,7 +331,7 @@ func (r *codeRepo) findDir(version string) (rev, dir string, gomod []byte, err e
 	found1 := err1 == nil && isMajor(mpath1, r.pathMajor)
 
 	var file2 string
-	if r.pathMajor != "" && !strings.HasPrefix(r.pathMajor, ".") {
+	if r.pathMajor != "" && r.codeRoot != r.modPath && !strings.HasPrefix(r.pathMajor, ".") {
 		// Suppose pathMajor is "/v2".
 		// Either go.mod should claim v2 and v2/go.mod should not exist,
 		// or v2/go.mod should exist and claim v2. Not both.
@@ -298,6 +339,9 @@ func (r *codeRepo) findDir(version string) (rev, dir string, gomod []byte, err e
 		// because of replacement modules. This might be a fork of
 		// the real module, found at a different path, usable only in
 		// a replace directive.
+		//
+		// TODO(bcmills): This doesn't seem right. Investigate futher.
+		// (Notably: why can't we replace foo/v2 with fork-of-foo/v3?)
 		dir2 := path.Join(r.codeDir, r.pathMajor[1:])
 		file2 = path.Join(dir2, "go.mod")
 		gomod2, err2 := r.code.ReadFile(rev, file2, codehost.MaxGoMod)
@@ -418,7 +462,7 @@ func (r *codeRepo) Zip(dst io.Writer, version string) error {
 	}
 	defer dl.Close()
 	if actualDir != "" && !hasPathPrefix(dir, actualDir) {
-		return fmt.Errorf("internal error: downloading %v %v: dir=%q but actualDir=%q", r.path, rev, dir, actualDir)
+		return fmt.Errorf("internal error: downloading %v %v: dir=%q but actualDir=%q", r.modPath, rev, dir, actualDir)
 	}
 	subdir := strings.Trim(strings.TrimPrefix(dir, actualDir), "/")
 

src/cmd/go/internal/modfetch/coderepo_test.go

@@ -323,6 +323,15 @@ var codeRepoTests = []struct {
 		time:    time.Date(2017, 5, 31, 16, 3, 50, 0, time.UTC),
 		gomod:   "module gopkg.in/natefinch/lumberjack.v2\n",
 	},
+	{
+		path:    "nanomsg.org/go/mangos/v2",
+		rev:     "v2.0.2",
+		version: "v2.0.2",
+		name:    "63f66a65137b9a648ac9f7bf0160b4a4d17d7999",
+		short:   "63f66a65137b",
+		time:    time.Date(2018, 12, 1, 15, 7, 40, 0, time.UTC),
+		gomod:   "module nanomsg.org/go/mangos/v2\n\nrequire (\n\tgithub.com/Microsoft/go-winio v0.4.11\n\tgithub.com/droundy/goopt v0.0.0-20170604162106-0b8effe182da\n\tgithub.com/gopherjs/gopherjs v0.0.0-20181103185306-d547d1d9531e // indirect\n\tgithub.com/gorilla/websocket v1.4.0\n\tgithub.com/jtolds/gls v4.2.1+incompatible // indirect\n\tgithub.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d // indirect\n\tgithub.com/smartystreets/goconvey v0.0.0-20181108003508-044398e4856c\n\tgolang.org/x/sys v0.0.0-20181128092732-4ed8d59d0b35 // indirect\n)\n",
+	},
 }
 
 func TestCodeRepo(t *testing.T) {

src/cmd/go/internal/test/test.go

@@ -805,7 +805,7 @@ func builderTest(b *work.Builder, p *load.Package) (buildAction, runAction, prin
 	if p.ImportPath == "command-line-arguments" {
 		elem = p.Name
 	} else {
-		_, elem = path.Split(p.ImportPath)
+		elem = load.DefaultExecName(p.ImportPath)
 	}
 	testBinary := elem + ".test"
 

src/cmd/go/internal/work/build.go

@@ -10,7 +10,6 @@ import (
 	"go/build"
 	"os"
 	"os/exec"
-	"path"
 	"path/filepath"
 	"runtime"
 	"strings"
@@ -285,7 +284,7 @@ func runBuild(cmd *base.Command, args []string) {
 	pkgs := load.PackagesForBuild(args)
 
 	if len(pkgs) == 1 && pkgs[0].Name == "main" && cfg.BuildO == "" {
-		_, cfg.BuildO = path.Split(pkgs[0].ImportPath)
+		cfg.BuildO = load.DefaultExecName(pkgs[0].ImportPath)
 		cfg.BuildO += cfg.ExeSuffix
 	}
 
@@ -518,7 +517,7 @@ func InstallPackages(patterns []string, pkgs []*load.Package) {
 	if len(patterns) == 0 && len(pkgs) == 1 && pkgs[0].Name == "main" {
 		// Compute file 'go build' would have created.
 		// If it exists and is an executable file, remove it.
-		_, targ := filepath.Split(pkgs[0].ImportPath)
+		targ := load.DefaultExecName(pkgs[0].ImportPath)
 		targ += cfg.ExeSuffix
 		if filepath.Join(pkgs[0].Dir, targ) != pkgs[0].Target { // maybe $GOBIN is the current directory
 			fi, err := os.Stat(targ)

src/cmd/go/internal/work/exec.go

@@ -214,6 +214,7 @@ func (b *Builder) buildActionID(a *Action) cache.ActionID {
 	if p.Internal.CoverMode != "" {
 		fmt.Fprintf(h, "cover %q %q\n", p.Internal.CoverMode, b.toolID("cover"))
 	}
+	fmt.Fprintf(h, "modinfo %q\n", p.Internal.BuildInfo)
 
 	// Configuration specific to compiler toolchain.
 	switch cfg.BuildToolchainName {
@@ -655,7 +656,7 @@ func (b *Builder) build(a *Action) (err error) {
 	if len(out) > 0 {
 		output := b.processOutput(out)
 		if p.Module != nil && !allowedVersion(p.Module.GoVersion) {
-			output += "note: module requires Go " + p.Module.GoVersion
+			output += "note: module requires Go " + p.Module.GoVersion + "\n"
 		}
 		b.showOutput(a, a.Package.Dir, a.Package.Desc(), output)
 		if err != nil {

src/cmd/go/internal/work/security.go

@@ -177,6 +177,8 @@ var validLinkerFlags = []*regexp.Regexp{
 	re(`-Wl,-framework,[^,@\-][^,]+`),
 	re(`-Wl,-headerpad_max_install_names`),
 	re(`-Wl,--no-undefined`),
+	re(`-Wl,-R([^@\-][^,@]*$)`),
+	re(`-Wl,--just-symbols[=,]([^,@\-][^,@]+)`),
 	re(`-Wl,-rpath(-link)?[=,]([^,@\-][^,]+)`),
 	re(`-Wl,-s`),
 	re(`-Wl,-search_paths_first`),
@@ -206,6 +208,8 @@ var validLinkerFlagsWithNextArg = []string{
 	"-target",
 	"-Wl,-framework",
 	"-Wl,-rpath",
+	"-Wl,-R",
+	"-Wl,--just-symbols",
 	"-Wl,-undefined",
 }
 

src/cmd/go/internal/work/security_test.go

@@ -125,6 +125,11 @@ var goodLinkerFlags = [][]string{
 	{"-pthread"},
 	{"-Wl,-rpath,foo"},
 	{"-Wl,-rpath,$ORIGIN/foo"},
+	{"-Wl,-R", "/foo"},
+	{"-Wl,-R", "foo"},
+	{"-Wl,-R,foo"},
+	{"-Wl,--just-symbols=foo"},
+	{"-Wl,--just-symbols,foo"},
 	{"-Wl,--warn-error"},
 	{"-Wl,--no-warn-error"},
 	{"foo.so"},
@@ -197,6 +202,9 @@ var badLinkerFlags = [][]string{
 	{"-x", "--c"},
 	{"-x", "@obj"},
 	{"-Wl,-rpath,@foo"},
+	{"-Wl,-R,foo,bar"},
+	{"-Wl,-R,@foo"},
+	{"-Wl,--just-symbols,@foo"},
 	{"../x.o"},
 }
 

src/cmd/go/testdata/mod/rsc.io_fortune_v2_v2.0.0.txt

@@ -13,3 +13,9 @@ import "rsc.io/quote"
 func main() {
 	println(quote.Hello())
 }
+-- fortune_test.go --
+package main
+
+import "testing"
+
+func TestFortuneV2(t *testing.T) {}

src/cmd/go/testdata/script/build_nocache.txt

@@ -10,6 +10,11 @@ env HOME=
 ! go build -o triv triv.go
 stderr 'build cache is required, but could not be located: GOCACHE is not defined and .*'
 
+# If GOCACHE is set but is not an absolute path, and we cannot build.
+env GOCACHE=test
+! go build -o triv triv.go
+stderr 'build cache is required, but could not be located: GOCACHE is not an absolute path'
+
 # An explicit GOCACHE=off also disables builds.
 env GOCACHE=off
 ! go build -o triv triv.go

src/cmd/go/testdata/script/cover_pkgall_multiple_mains.txt

@@ -0,0 +1,43 @@
+# This test checks that multiple main packages can be tested
+# with -coverpkg=all without duplicate symbol errors.
+# Verifies golang.org/issue/30374.
+
+env GO111MODULE=on
+
+[short] skip
+
+go test -coverpkg=all ./...
+
+-- go.mod --
+module example.com/cov
+
+-- mainonly/mainonly.go --
+package main
+
+func main() {}
+
+-- mainwithtest/mainwithtest.go --
+package main
+
+func main() {}
+
+func Foo() {}
+
+-- mainwithtest/mainwithtest_test.go --
+package main
+
+import "testing"
+
+func TestFoo(t *testing.T) {
+  Foo()
+}
+
+-- xtest/x.go --
+package x
+
+-- xtest/x_test.go --
+package x_test
+
+import "testing"
+
+func TestX(t *testing.T) {}

src/cmd/go/testdata/script/mod_build_versioned.txt

@@ -0,0 +1,16 @@
+env GO111MODULE=on
+
+go get -m rsc.io/fortune/v2
+
+# The default executable name shouldn't be v2$exe
+go build rsc.io/fortune/v2
+! exists v2$exe
+exists fortune$exe
+
+# The default test binary name shouldn't be v2.test$exe
+go test -c rsc.io/fortune/v2
+! exists v2.test$exe
+exists fortune.test$exe
+
+-- go.mod --
+module scratch

src/cmd/go/testdata/script/mod_symlink.txt

@@ -2,16 +2,31 @@ env GO111MODULE=on
 [!symlink] skip
 
 # 'go list' should resolve modules of imported packages.
-go list -deps -f '{{.Module}}'
+go list -deps -f '{{.Module}}' .
 stdout golang.org/x/text
 
-# They should continue to resolve if the importing file is a symlink.
-mkdir links
-cd links
-symlink go.mod -> ../go.mod
-symlink issue.go -> ../issue.go
+go list -deps -f '{{.Module}}' ./subpkg
+stdout golang.org/x/text
 
-go list -deps -f '{{.Module}}'
+# Create a copy of the module using symlinks in src/links.
+mkdir links
+symlink links/go.mod -> $GOPATH/src/go.mod
+symlink links/issue.go -> $GOPATH/src/issue.go
+mkdir links/subpkg
+symlink links/subpkg/issue.go -> $GOPATH/src/subpkg/issue.go
+
+# We should see the copy as a valid module root.
+cd links
+go env GOMOD
+stdout links[/\\]go.mod
+go list -m
+stdout golang.org/issue/28107
+
+# The symlink-based copy should contain the same packages
+# and have the same dependencies as the original.
+go list -deps -f '{{.Module}}' .
+stdout golang.org/x/text
+go list -deps -f '{{.Module}}' ./subpkg
 stdout golang.org/x/text
 
 -- go.mod --
@@ -21,3 +36,7 @@ module golang.org/issue/28107
 package issue
 
 import _ "golang.org/x/text/language"
+-- subpkg/issue.go --
+package issue
+
+import _ "golang.org/x/text/language"

src/cmd/internal/obj/arm64/asm7.go

@@ -2986,7 +2986,7 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) {
 		num := uint8(0)
 		cls := oclass(&p.From)
 		if isADDWop(p.As) {
-			if (cls != C_LCON) && (cls != C_ADDCON2) {
+			if !cmp(C_LCON, cls) {
 				c.ctxt.Diag("illegal combination: %v", p)
 			}
 			num = c.omovlconst(AMOVW, p, &p.From, REGTMP, os[:])
@@ -3271,7 +3271,7 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) {
 		num := uint8(0)
 		cls := oclass(&p.From)
 		if isANDWop(p.As) {
-			if (cls != C_LCON) && (cls != C_ADDCON) {
+			if !cmp(C_LCON, cls) {
 				c.ctxt.Diag("illegal combination: %v", p)
 			}
 			num = c.omovlconst(AMOVW, p, &p.From, REGTMP, os[:])

src/cmd/link/elf_test.go

@@ -0,0 +1,113 @@
+// 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 dragonfly freebsd linux netbsd openbsd
+
+package main
+
+import (
+	"internal/testenv"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+var asmSource = `
+	.section .text1,"ax"
+s1:
+	.byte 0
+	.section .text2,"ax"
+s2:
+	.byte 0
+`
+
+var goSource = `
+package main
+func main() {}
+`
+
+// The linker used to crash if an ELF input file had multiple text sections
+// with the same name.
+func TestSectionsWithSameName(t *testing.T) {
+	testenv.MustHaveGoBuild(t)
+	testenv.MustHaveCGO(t)
+	t.Parallel()
+
+	objcopy, err := exec.LookPath("objcopy")
+	if err != nil {
+		t.Skipf("can't find objcopy: %v", err)
+	}
+
+	dir, err := ioutil.TempDir("", "go-link-TestSectionsWithSameName")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+
+	gopath := filepath.Join(dir, "GOPATH")
+	env := append(os.Environ(), "GOPATH="+gopath)
+
+	if err := ioutil.WriteFile(filepath.Join(dir, "go.mod"), []byte("module elf_test\n"), 0666); err != nil {
+		t.Fatal(err)
+	}
+
+	asmFile := filepath.Join(dir, "x.s")
+	if err := ioutil.WriteFile(asmFile, []byte(asmSource), 0444); err != nil {
+		t.Fatal(err)
+	}
+
+	goTool := testenv.GoToolPath(t)
+	cmd := exec.Command(goTool, "env", "CC")
+	cmd.Env = env
+	ccb, err := cmd.Output()
+	if err != nil {
+		t.Fatal(err)
+	}
+	cc := strings.TrimSpace(string(ccb))
+
+	cmd = exec.Command(goTool, "env", "GOGCCFLAGS")
+	cmd.Env = env
+	cflagsb, err := cmd.Output()
+	if err != nil {
+		t.Fatal(err)
+	}
+	cflags := strings.Fields(string(cflagsb))
+
+	asmObj := filepath.Join(dir, "x.o")
+	t.Logf("%s %v -c -o %s %s", cc, cflags, asmObj, asmFile)
+	if out, err := exec.Command(cc, append(cflags, "-c", "-o", asmObj, asmFile)...).CombinedOutput(); err != nil {
+		t.Logf("%s", out)
+		t.Fatal(err)
+	}
+
+	asm2Obj := filepath.Join(dir, "x2.syso")
+	t.Logf("%s --rename-section .text2=.text1 %s %s", objcopy, asmObj, asm2Obj)
+	if out, err := exec.Command(objcopy, "--rename-section", ".text2=.text1", asmObj, asm2Obj).CombinedOutput(); err != nil {
+		t.Logf("%s", out)
+		t.Fatal(err)
+	}
+
+	for _, s := range []string{asmFile, asmObj} {
+		if err := os.Remove(s); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	goFile := filepath.Join(dir, "main.go")
+	if err := ioutil.WriteFile(goFile, []byte(goSource), 0444); err != nil {
+		t.Fatal(err)
+	}
+
+	cmd = exec.Command(goTool, "build")
+	cmd.Dir = dir
+	cmd.Env = env
+	t.Logf("%s build", goTool)
+	if out, err := cmd.CombinedOutput(); err != nil {
+		t.Logf("%s", out)
+		t.Fatal(err)
+	}
+}

src/cmd/link/internal/ld/lib.go

@@ -1802,7 +1802,15 @@ func ldshlibsyms(ctxt *Link, shlib string) {
 		if elf.ST_TYPE(elfsym.Info) == elf.STT_NOTYPE || elf.ST_TYPE(elfsym.Info) == elf.STT_SECTION {
 			continue
 		}
-		lsym := ctxt.Syms.Lookup(elfsym.Name, 0)
+
+		// Symbols whose names start with "type." are compiler
+		// generated, so make functions with that prefix internal.
+		ver := 0
+		if elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC && strings.HasPrefix(elfsym.Name, "type.") {
+			ver = sym.SymVerABIInternal
+		}
+
+		lsym := ctxt.Syms.Lookup(elfsym.Name, ver)
 		// Because loadlib above loads all .a files before loading any shared
 		// libraries, any non-dynimport symbols we find that duplicate symbols
 		// already loaded should be ignored (the symbols from the .a files
@@ -1830,7 +1838,7 @@ func ldshlibsyms(ctxt *Link, shlib string) {
 		// the ABIs are actually different. We might have to
 		// mangle Go function names in the .so to include the
 		// ABI.
-		if elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC {
+		if elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC && ver == 0 {
 			alias := ctxt.Syms.Lookup(elfsym.Name, sym.SymVerABIInternal)
 			if alias.Type != 0 {
 				continue
@@ -1958,7 +1966,7 @@ func stkcheck(ctxt *Link, up *chain, depth int) int {
 		s.Attr |= sym.AttrStackCheck
 	}
 
-	if depth > 100 {
+	if depth > 500 {
 		Errorf(s, "nosplit stack check too deep")
 		stkbroke(ctxt, up, 0)
 		return -1

src/cmd/link/internal/ld/macho.go

@@ -662,9 +662,11 @@ func Asmbmacho(ctxt *Link) {
 		// and we can assume OS X.
 		//
 		// See golang.org/issues/12941.
+		//
+		// The version must be at least 10.9; see golang.org/issues/30488.
 		ml := newMachoLoad(ctxt.Arch, LC_VERSION_MIN_MACOSX, 2)
-		ml.data[0] = 10<<16 | 7<<8 | 0<<0 // OS X version 10.7.0
-		ml.data[1] = 10<<16 | 7<<8 | 0<<0 // SDK 10.7.0
+		ml.data[0] = 10<<16 | 9<<8 | 0<<0 // OS X version 10.9.0
+		ml.data[1] = 10<<16 | 9<<8 | 0<<0 // SDK 10.9.0
 	}
 
 	a := machowrite(ctxt.Arch, ctxt.Out, ctxt.LinkMode)

src/cmd/link/internal/ld/macho_combine_dwarf.go

@@ -265,7 +265,7 @@ func machoCombineDwarf(ctxt *Link, inexe, dsym, outexe string) (bool, error) {
 		}
 	}
 	// Do the final update of the DWARF segment's load command.
-	return false, machoUpdateDwarfHeader(&reader, ctxt.BuildMode, compressedSects)
+	return false, machoUpdateDwarfHeader(&reader, compressedSects, dwarfsize)
 }
 
 // machoCompressSections tries to compress the DWARF segments in dwarfm,
@@ -410,7 +410,7 @@ func machoUpdateSections(r loadCmdReader, seg, sect reflect.Value, deltaOffset,
 }
 
 // machoUpdateDwarfHeader updates the DWARF segment load command.
-func machoUpdateDwarfHeader(r *loadCmdReader, buildmode BuildMode, compressedSects []*macho.Section) error {
+func machoUpdateDwarfHeader(r *loadCmdReader, compressedSects []*macho.Section, dwarfsize uint64) error {
 	var seg, sect interface{}
 	cmd, err := r.Next()
 	if err != nil {
@@ -428,7 +428,6 @@ func machoUpdateDwarfHeader(r *loadCmdReader, buildmode BuildMode, compressedSec
 	}
 	segv := reflect.ValueOf(seg).Elem()
 	segv.FieldByName("Offset").SetUint(uint64(dwarfstart))
-	segv.FieldByName("Addr").SetUint(uint64(dwarfaddr))
 
 	if compressedSects != nil {
 		var segSize uint64
@@ -436,23 +435,27 @@ func machoUpdateDwarfHeader(r *loadCmdReader, buildmode BuildMode, compressedSec
 			segSize += newSect.Size
 		}
 		segv.FieldByName("Filesz").SetUint(segSize)
-		segv.FieldByName("Memsz").SetUint(uint64(Rnd(int64(segSize), 1<<pageAlign)))
+	} else {
+		segv.FieldByName("Filesz").SetUint(dwarfsize)
 	}
 
 	deltaOffset := uint64(dwarfstart) - realdwarf.Offset
 	deltaAddr := uint64(dwarfaddr) - realdwarf.Addr
 
-	// If we set Memsz to 0 (and might as well set Addr too),
-	// then the xnu kernel will bail out halfway through load_segment
-	// and not apply further sanity checks that we might fail in the future.
-	// We don't need the DWARF information actually available in memory.
-	// But if we do this for buildmode=c-shared then the user-space
-	// dynamic loader complains about memsz < filesz. Sigh.
-	if buildmode != BuildModeCShared {
-		segv.FieldByName("Addr").SetUint(0)
-		segv.FieldByName("Memsz").SetUint(0)
-		deltaAddr = 0
-	}
+	// We want the DWARF segment to be considered non-loadable, so
+	// force vmaddr and vmsize to zero. In addition, set the initial
+	// protection to zero so as to make the dynamic loader happy,
+	// since otherwise it may complain that that the vm size and file
+	// size don't match for the segment. See issues 21647 and 32673
+	// for more context. Also useful to refer to the Apple dynamic
+	// loader source, specifically ImageLoaderMachO::sniffLoadCommands
+	// in ImageLoaderMachO.cpp (various versions can be found online, see
+	// https://opensource.apple.com/source/dyld/dyld-519.2.2/src/ImageLoaderMachO.cpp.auto.html
+	// as one example).
+	segv.FieldByName("Addr").SetUint(0)
+	segv.FieldByName("Memsz").SetUint(0)
+	segv.FieldByName("Prot").SetUint(0)
+	deltaAddr = 0
 
 	if err := r.WriteAt(0, seg); err != nil {
 		return err

src/cmd/link/internal/ld/pcln.go

@@ -325,7 +325,7 @@ func (ctxt *Link) pclntab() {
 				// set the resumption point to PC_B.
 				lastWasmAddr = uint32(r.Add)
 			}
-			if r.Sym != nil && r.Sym.Name == "runtime.deferreturn" && r.Add == 0 {
+			if r.Type.IsDirectJump() && r.Sym != nil && r.Sym.Name == "runtime.deferreturn" {
 				if ctxt.Arch.Family == sys.Wasm {
 					deferreturn = lastWasmAddr
 				} else {

src/cmd/link/internal/loadelf/ldelf.go

@@ -678,6 +678,8 @@ func Load(arch *sys.Arch, syms *sym.Symbols, f *bio.Reader, pkg string, length i
 	// as well use one large chunk.
 
 	// create symbols for elfmapped sections
+	sectsymNames := make(map[string]bool)
+	counter := 0
 	for i := 0; uint(i) < elfobj.nsect; i++ {
 		sect = &elfobj.sect[i]
 		if sect.type_ == SHT_ARM_ATTRIBUTES && sect.name == ".ARM.attributes" {
@@ -709,6 +711,12 @@ func Load(arch *sys.Arch, syms *sym.Symbols, f *bio.Reader, pkg string, length i
 		}
 
 		name := fmt.Sprintf("%s(%s)", pkg, sect.name)
+		for sectsymNames[name] {
+			counter++
+			name = fmt.Sprintf("%s(%s%d)", pkg, sect.name, counter)
+		}
+		sectsymNames[name] = true
+
 		s := syms.Lookup(name, localSymVersion)
 
 		switch int(sect.flags) & (ElfSectFlagAlloc | ElfSectFlagWrite | ElfSectFlagExec) {

src/cmd/link/link_test.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"debug/macho"
 	"internal/testenv"
 	"io/ioutil"
 	"os"
@@ -171,3 +172,67 @@ main.x: relocation target main.zero not defined
 		t.Fatalf("want:\n%sgot:\n%s", want, got)
 	}
 }
+
+var testMacOSVersionSrc = `
+package main
+func main() { }
+`
+
+func TestMacOSVersion(t *testing.T) {
+	testenv.MustHaveGoBuild(t)
+
+	tmpdir, err := ioutil.TempDir("", "TestMacOSVersion")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(tmpdir)
+
+	src := filepath.Join(tmpdir, "main.go")
+	err = ioutil.WriteFile(src, []byte(testMacOSVersionSrc), 0666)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	exe := filepath.Join(tmpdir, "main")
+	cmd := exec.Command(testenv.GoToolPath(t), "build", "-ldflags=-linkmode=internal", "-o", exe, src)
+	cmd.Env = append(os.Environ(),
+		"CGO_ENABLED=0",
+		"GOOS=darwin",
+		"GOARCH=amd64",
+	)
+	if out, err := cmd.CombinedOutput(); err != nil {
+		t.Fatalf("%v: %v:\n%s", cmd.Args, err, out)
+	}
+	exef, err := os.Open(exe)
+	if err != nil {
+		t.Fatal(err)
+	}
+	exem, err := macho.NewFile(exef)
+	if err != nil {
+		t.Fatal(err)
+	}
+	found := false
+	const LC_VERSION_MIN_MACOSX = 0x24
+	checkMin := func(ver uint32) {
+		major, minor := (ver>>16)&0xff, (ver>>8)&0xff
+		if major != 10 || minor < 9 {
+			t.Errorf("LC_VERSION_MIN_MACOSX version %d.%d < 10.9", major, minor)
+		}
+	}
+	for _, cmd := range exem.Loads {
+		raw := cmd.Raw()
+		type_ := exem.ByteOrder.Uint32(raw)
+		if type_ != LC_VERSION_MIN_MACOSX {
+			continue
+		}
+		osVer := exem.ByteOrder.Uint32(raw[8:])
+		checkMin(osVer)
+		sdkVer := exem.ByteOrder.Uint32(raw[12:])
+		checkMin(sdkVer)
+		found = true
+		break
+	}
+	if !found {
+		t.Errorf("no LC_VERSION_MIN_MACOSX load command found")
+	}
+}

src/cmd/vendor/golang.org/x/tools/go/analysis/analysis.go

@@ -87,6 +87,7 @@ type Pass struct {
 	OtherFiles []string       // names of non-Go files of this package
 	Pkg        *types.Package // type information about the package
 	TypesInfo  *types.Info    // type information about the syntax trees
+	TypesSizes types.Sizes    // function for computing sizes of types
 
 	// Report reports a Diagnostic, a finding about a specific location
 	// in the analyzed source code such as a potential mistake.

src/cmd/vendor/golang.org/x/tools/go/analysis/doc.go

@@ -246,7 +246,7 @@ An Analyzer that uses facts must declare their types:
 
 	var Analyzer = &analysis.Analyzer{
 		Name:       "printf",
-		FactTypes: []reflect.Type{reflect.TypeOf(new(isWrapper))},
+		FactTypes: []analysis.Fact{new(isWrapper)},
 		...
 	}
 

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go

@@ -114,7 +114,8 @@ func init() {
 			// library we cannot assume types.SizesFor is consistent with arches.
 			// For now, assume 64-bit norms and print a warning.
 			// But this warning should really be deferred until we attempt to use
-			// arch, which is very unlikely.
+			// arch, which is very unlikely. Better would be
+			// to defer size computation until we have Pass.TypesSizes.
 			arch.sizes = types.SizesFor("gc", "amd64")
 			log.Printf("unknown architecture %s", arch.name)
 		}

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/cgocall/cgocall.go

@@ -9,7 +9,6 @@ package cgocall
 import (
 	"fmt"
 	"go/ast"
-	"go/build"
 	"go/format"
 	"go/parser"
 	"go/token"
@@ -45,7 +44,7 @@ func run(pass *analysis.Pass) (interface{}, error) {
 		return nil, nil // doesn't use cgo
 	}
 
-	cgofiles, info, err := typeCheckCgoSourceFiles(pass.Fset, pass.Pkg, pass.Files, pass.TypesInfo)
+	cgofiles, info, err := typeCheckCgoSourceFiles(pass.Fset, pass.Pkg, pass.Files, pass.TypesInfo, pass.TypesSizes)
 	if err != nil {
 		return nil, err
 	}
@@ -171,7 +170,7 @@ func checkCgo(fset *token.FileSet, f *ast.File, info *types.Info, reportf func(t
 // limited ourselves here to preserving function bodies and initializer
 // expressions since that is all that the cgocall analyzer needs.
 //
-func typeCheckCgoSourceFiles(fset *token.FileSet, pkg *types.Package, files []*ast.File, info *types.Info) ([]*ast.File, *types.Info, error) {
+func typeCheckCgoSourceFiles(fset *token.FileSet, pkg *types.Package, files []*ast.File, info *types.Info, sizes types.Sizes) ([]*ast.File, *types.Info, error) {
 	const thispkg = "·this·"
 
 	// Which files are cgo files?
@@ -269,8 +268,7 @@ func typeCheckCgoSourceFiles(fset *token.FileSet, pkg *types.Package, files []*a
 		Importer: importerFunc(func(path string) (*types.Package, error) {
 			return importMap[path], nil
 		}),
-		// TODO(adonovan): Sizes should probably be provided by analysis.Pass.
-		Sizes: types.SizesFor("gc", build.Default.GOARCH),
+		Sizes: sizes,
 		Error: func(error) {}, // ignore errors (e.g. unused import)
 	}
 

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/composite/composite.go

@@ -21,7 +21,16 @@ const Doc = `check for unkeyed composite literals
 This analyzer reports a diagnostic for composite literals of struct
 types imported from another package that do not use the field-keyed
 syntax. Such literals are fragile because the addition of a new field
-(even if unexported) to the struct will cause compilation to fail.`
+(even if unexported) to the struct will cause compilation to fail.
+
+As an example,
+
+	err = &net.DNSConfigError{err}
+
+should be replaced by:
+
+	err = &net.DNSConfigError{Err: err}
+`
 
 var Analyzer = &analysis.Analyzer{
 	Name:             "composites",

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/inspect/inspect.go

@@ -8,7 +8,11 @@
 //
 // Example of use in another analysis:
 //
-//	import "golang.org/x/tools/go/analysis/passes/inspect"
+//	import (
+//		"golang.org/x/tools/go/analysis"
+//		"golang.org/x/tools/go/analysis/passes/inspect"
+//		"golang.org/x/tools/go/ast/inspector"
+//	)
 //
 //	var Analyzer = &analysis.Analyzer{
 //		...

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go

@@ -453,15 +453,23 @@ func printfNameAndKind(pass *analysis.Pass, call *ast.CallExpr) (fn *types.Func,
 }
 
 // isFormatter reports whether t satisfies fmt.Formatter.
-// Unlike fmt.Stringer, it's impossible to satisfy fmt.Formatter without importing fmt.
-func isFormatter(pass *analysis.Pass, t types.Type) bool {
-	for _, imp := range pass.Pkg.Imports() {
-		if imp.Path() == "fmt" {
-			formatter := imp.Scope().Lookup("Formatter").Type().Underlying().(*types.Interface)
-			return types.Implements(t, formatter)
-		}
+// The only interface method to look for is "Format(State, rune)".
+func isFormatter(typ types.Type) bool {
+	obj, _, _ := types.LookupFieldOrMethod(typ, false, nil, "Format")
+	fn, ok := obj.(*types.Func)
+	if !ok {
+		return false
 	}
-	return false
+	sig := fn.Type().(*types.Signature)
+	return sig.Params().Len() == 2 &&
+		sig.Results().Len() == 0 &&
+		isNamed(sig.Params().At(0).Type(), "fmt", "State") &&
+		types.Identical(sig.Params().At(1).Type(), types.Typ[types.Rune])
+}
+
+func isNamed(T types.Type, pkgpath, name string) bool {
+	named, ok := T.(*types.Named)
+	return ok && named.Obj().Pkg().Path() == pkgpath && named.Obj().Name() == name
 }
 
 // formatState holds the parsed representation of a printf directive such as "%3.*[4]d".
@@ -753,7 +761,7 @@ func okPrintfArg(pass *analysis.Pass, call *ast.CallExpr, state *formatState) (o
 	formatter := false
 	if state.argNum < len(call.Args) {
 		if tv, ok := pass.TypesInfo.Types[call.Args[state.argNum]]; ok {
-			formatter = isFormatter(pass, tv.Type)
+			formatter = isFormatter(tv.Type)
 		}
 	}
 
@@ -831,7 +839,7 @@ func recursiveStringer(pass *analysis.Pass, e ast.Expr) bool {
 	typ := pass.TypesInfo.Types[e].Type
 
 	// It's unlikely to be a recursive stringer if it has a Format method.
-	if isFormatter(pass, typ) {
+	if isFormatter(typ) {
 		return false
 	}
 

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/types.go

@@ -2,7 +2,6 @@ package printf
 
 import (
 	"go/ast"
-	"go/build"
 	"go/types"
 
 	"golang.org/x/tools/go/analysis"
@@ -39,7 +38,7 @@ func matchArgTypeInternal(pass *analysis.Pass, t printfArgType, typ types.Type,
 		}
 	}
 	// If the type implements fmt.Formatter, we have nothing to check.
-	if isFormatter(pass, typ) {
+	if isFormatter(typ) {
 		return true
 	}
 	// If we can use a string, might arg (dynamically) implement the Stringer or Error interface?
@@ -235,5 +234,3 @@ func matchStructArgType(pass *analysis.Pass, t printfArgType, typ *types.Struct,
 	}
 	return true
 }
-
-var archSizes = types.SizesFor("gc", build.Default.GOARCH)

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/shift/shift.go

@@ -12,10 +12,8 @@ package shift
 
 import (
 	"go/ast"
-	"go/build"
 	"go/constant"
 	"go/token"
-	"go/types"
 
 	"golang.org/x/tools/go/analysis"
 	"golang.org/x/tools/go/analysis/passes/inspect"
@@ -93,36 +91,9 @@ func checkLongShift(pass *analysis.Pass, node ast.Node, x, y ast.Expr) {
 	if t == nil {
 		return
 	}
-	b, ok := t.Underlying().(*types.Basic)
-	if !ok {
-		return
-	}
-	var size int64
-	switch b.Kind() {
-	case types.Uint8, types.Int8:
-		size = 8
-	case types.Uint16, types.Int16:
-		size = 16
-	case types.Uint32, types.Int32:
-		size = 32
-	case types.Uint64, types.Int64:
-		size = 64
-	case types.Int, types.Uint:
-		size = uintBitSize
-	case types.Uintptr:
-		size = uintptrBitSize
-	default:
-		return
-	}
+	size := 8 * pass.TypesSizes.Sizeof(t)
 	if amt >= size {
 		ident := analysisutil.Format(pass.Fset, x)
 		pass.Reportf(node.Pos(), "%s (%d bits) too small for shift of %d", ident, size, amt)
 	}
 }
-
-var (
-	uintBitSize    = 8 * archSizes.Sizeof(types.Typ[types.Uint])
-	uintptrBitSize = 8 * archSizes.Sizeof(types.Typ[types.Uintptr])
-)
-
-var archSizes = types.SizesFor("gc", build.Default.GOARCH)

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/structtag/structtag.go

@@ -96,6 +96,11 @@ func checkTagDuplicates(pass *analysis.Pass, tag, key string, nearest, field *ty
 	}
 	if val == "" || val[0] == ',' {
 		if field.Anonymous() {
+			// Disable this check enhancement in Go 1.12.1; some
+			// false positives were spotted in the initial 1.12
+			// release. See https://golang.org/issues/30465.
+			return
+
 			typ, ok := field.Type().Underlying().(*types.Struct)
 			if !ok {
 				return

src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go

@@ -329,6 +329,7 @@ func run(fset *token.FileSet, cfg *Config, analyzers []*analysis.Analyzer) ([]re
 				OtherFiles:        cfg.NonGoFiles,
 				Pkg:               pkg,
 				TypesInfo:         info,
+				TypesSizes:        tc.Sizes,
 				ResultOf:          inputs,
 				Report:            func(d analysis.Diagnostic) { act.diagnostics = append(act.diagnostics, d) },
 				ImportObjectFact:  facts.ImportObjectFact,

src/cmd/vendor/golang.org/x/tools/go/ast/inspector/inspector.go

@@ -14,7 +14,7 @@
 // Experiments suggest the inspector's traversals are about 2.5x faster
 // than ast.Inspect, but it may take around 5 traversals for this
 // benefit to amortize the inspector's construction cost.
-// If efficiency is the primary concern, do not use use Inspector for
+// If efficiency is the primary concern, do not use Inspector for
 // one-off traversals.
 package inspector
 

src/cmd/vet/testdata/src/print2/big.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 print2
+
+import ( // NOTE: Does not import "fmt"
+	"log"
+	"math/big"
+)
+
+var fmt int
+
+func f() {
+	log.Printf("%d", new(big.Int))
+	log.Printf("%d", 1.0) // ERROR "Printf format %d has arg 1.0 of wrong type float64"
+}

src/cmd/vet/testdata/src/structtag/structtag.go

@@ -6,6 +6,20 @@
 
 package structtag
 
+import "encoding/json"
+
 type StructTagTest struct {
 	A int "hello" // ERROR "`hello` not compatible with reflect.StructTag.Get: bad syntax for struct tag pair"
 }
+
+func Issue30465() {
+	type T1 struct {
+		X string `json:"x"`
+	}
+	type T2 struct {
+		T1
+		X string `json:"x"`
+	}
+	var t2 T2
+	json.Marshal(&t2)
+}

src/cmd/vet/vet_test.go

@@ -88,6 +88,7 @@ func TestVet(t *testing.T) {
 		"method",
 		"nilfunc",
 		"print",
+		"print2",
 		"rangeloop",
 		"shift",
 		"structtag",

src/crypto/rc4/rc4.go

@@ -45,8 +45,10 @@ func NewCipher(key []byte) (*Cipher, error) {
 	return &c, nil
 }
 
-// Reset zeros the key data so that it will no longer appear in the
-// process's memory.
+// Reset zeros the key data and makes the Cipher unusable.
+//
+// Deprecated: Reset can't guarantee that the key will be entirely removed from
+// the process's memory.
 func (c *Cipher) Reset() {
 	for i := range c.s {
 		c.s[i] = 0

src/crypto/tls/handshake_client.go

@@ -573,7 +573,7 @@ func (hs *clientHandshakeState) doFullHandshake() error {
 			return fmt.Errorf("tls: client certificate private key of type %T does not implement crypto.Signer", chainToSend.PrivateKey)
 		}
 
-		signatureAlgorithm, sigType, hashFunc, err := pickSignatureAlgorithm(key.Public(), certReq.supportedSignatureAlgorithms, hs.hello.supportedSignatureAlgorithms, c.vers)
+		signatureAlgorithm, sigType, hashFunc, err := pickSignatureAlgorithm(key.Public(), certReq.supportedSignatureAlgorithms, supportedSignatureAlgorithmsTLS12, c.vers)
 		if err != nil {
 			c.sendAlert(alertInternalError)
 			return err

src/crypto/tls/handshake_client_test.go

@@ -873,10 +873,41 @@ func TestHandshakeClientCertPSSDisabled(t *testing.T) {
 	supportedSignatureAlgorithmsTLS12 = savedSupportedSignatureAlgorithmsTLS12
 
 	// Use t.Run to ensure the defer runs after all parallel tests end.
-	t.Run("", func(t *testing.T) {
+	t.Run("1024", func(t *testing.T) {
 		runClientTestTLS12(t, test)
 		runClientTestTLS13(t, test)
 	})
+
+	// Use a 512-bit key to check that the TLS 1.2 handshake is actually using
+	// PKCS#1 v1.5. PSS would be failing here.
+	cert, err := X509KeyPair([]byte(`-----BEGIN CERTIFICATE-----
+MIIBcTCCARugAwIBAgIQGjQnkCFlUqaFlt6ixyz/tDANBgkqhkiG9w0BAQsFADAS
+MRAwDgYDVQQKEwdBY21lIENvMB4XDTE5MDExODIzMjMyOFoXDTIwMDExODIzMjMy
+OFowEjEQMA4GA1UEChMHQWNtZSBDbzBcMA0GCSqGSIb3DQEBAQUAA0sAMEgCQQDd
+ez1rFUDwax2HTxbcnFUP9AhcgEGMHVV2nn4VVEWFJB6I8C/Nkx0XyyQlrmFYBzEQ
+nIPhKls4T0hFoLvjJnXpAgMBAAGjTTBLMA4GA1UdDwEB/wQEAwIFoDATBgNVHSUE
+DDAKBggrBgEFBQcDATAMBgNVHRMBAf8EAjAAMBYGA1UdEQQPMA2CC2V4YW1wbGUu
+Y29tMA0GCSqGSIb3DQEBCwUAA0EAxDuUS+BrrS3c+h+k+fQPOmOScy6yTX9mHw0Q
+KbucGamXYEy0URIwOdO0tQ3LHPc1YGvYSPwkDjkjqECs2Vm/AA==
+-----END CERTIFICATE-----`), []byte(`-----BEGIN RSA PRIVATE KEY-----
+MIIBOgIBAAJBAN17PWsVQPBrHYdPFtycVQ/0CFyAQYwdVXaefhVURYUkHojwL82T
+HRfLJCWuYVgHMRCcg+EqWzhPSEWgu+MmdekCAwEAAQJBALjQYNTdXF4CFBbXwUz/
+yt9QFDYT9B5WT/12jeGAe653gtYS6OOi/+eAkGmzg1GlRnw6fOfn+HYNFDORST7z
+4j0CIQDn2xz9hVWQEu9ee3vecNT3f60huDGTNoRhtqgweQGX0wIhAPSLj1VcRZEz
+nKpbtU22+PbIMSJ+e80fmY9LIPx5N4HTAiAthGSimMR9bloz0EY3GyuUEyqoDgMd
+hXxjuno2WesoJQIgemilbcALXpxsLmZLgcQ2KSmaVr7jb5ECx9R+hYKTw1sCIG4s
+T+E0J8wlH24pgwQHzy7Ko2qLwn1b5PW8ecrlvP1g
+-----END RSA PRIVATE KEY-----`))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	test.name = "ClientCert-RSA-PSS-Disabled-512"
+	config.Certificates = []Certificate{cert}
+
+	t.Run("512", func(t *testing.T) {
+		runClientTestTLS12(t, test)
+	})
 }
 
 func TestClientKeyUpdate(t *testing.T) {

src/crypto/tls/testdata/Client-TLSv12-ClientCert-RSA-PSS-Disabled

@@ -16,11 +16,11 @@
 000000e0  a3 47 cd 62 43 15 28 da  ac 5f bb 29 07 30 ff f6  |.G.bC.(.._.).0..|
 000000f0  84 af c4 cf c2 ed 90 99  5f 58 cb 3b 74           |........_X.;t|
 >>> Flow 2 (server to client)
-00000000  16 03 03 00 59 02 00 00  55 03 03 33 ad 8d f8 90  |....Y...U..3....|
-00000010  d1 72 5d ef e8 94 0f d7  58 15 59 9f 0b f9 ec 73  |.r].....X.Y....s|
-00000020  99 53 f7 03 81 53 1a aa  05 f0 17 20 55 a1 9e 4e  |.S...S..... U..N|
-00000030  98 26 6b b8 d5 bc 2c 3e  ca f6 a0 d9 bb f2 3b dd  |.&k...,>......;.|
-00000040  be 99 f1 35 de 1c f6 51  5b 19 4f 55 c0 2f 00 00  |...5...Q[.OU./..|
+00000000  16 03 03 00 59 02 00 00  55 03 03 05 c1 62 2b 2f  |....Y...U....b+/|
+00000010  12 46 4d c5 47 61 bd 43  6d bb 3a 60 42 c1 cf da  |.FM.Ga.Cm.:`B...|
+00000020  47 96 0a 11 35 f0 71 d8  f6 39 69 20 0f 9c c1 3f  |G...5.q..9i ...?|
+00000030  9c 68 e7 86 13 7c 1f 83  6b 56 39 ee 0d c0 82 0b  |.h...|..kV9.....|
+00000040  24 1b 8a 39 a6 dc bf 57  79 27 02 e4 c0 2f 00 00  |$..9...Wy'.../..|
 00000050  0d ff 01 00 01 00 00 0b  00 04 03 00 01 02 16 03  |................|
 00000060  03 02 59 0b 00 02 55 00  02 52 00 02 4f 30 82 02  |..Y...U..R..O0..|
 00000070  4b 30 82 01 b4 a0 03 02  01 02 02 09 00 e8 f0 9d  |K0..............|
@@ -60,17 +60,17 @@
 00000290  77 8d 0c 1c f1 0f a1 d8  40 83 61 c9 4c 72 2b 9d  |w.......@.a.Lr+.|
 000002a0  ae db 46 06 06 4d f4 c1  b3 3e c0 d1 bd 42 d4 db  |..F..M...>...B..|
 000002b0  fe 3d 13 60 84 5c 21 d3  3b e9 fa e7 16 03 03 00  |.=.`.\!.;.......|
-000002c0  ac 0c 00 00 a8 03 00 1d  20 2d c8 0c d2 27 fc f9  |........ -...'..|
-000002d0  79 71 c4 17 ea 45 ec 0b  dd 66 ce af ec 49 96 7d  |yq...E...f...I.}|
-000002e0  43 ff 88 68 b1 a8 bb e1  38 08 04 00 80 5a ab 5b  |C..h....8....Z.[|
-000002f0  e6 b3 32 e2 98 ae c3 ed  7c f9 90 c4 a4 ea dd 70  |..2.....|......p|
-00000300  fc a4 f8 ef d1 15 0d b7  ad b8 e3 1f 3e c0 e4 40  |............>..@|
-00000310  0d 7b 50 36 8f 88 cb 88  59 7c 20 63 d1 7f 36 9e  |.{P6....Y| c..6.|
-00000320  de a7 cb 6a 49 fd 65 32  36 0b 10 6a df 58 ef fd  |...jI.e26..j.X..|
-00000330  f6 fc e6 65 e7 81 0e 73  25 87 c7 89 dc ec ae 7c  |...e...s%......||
-00000340  e4 81 79 79 a2 b9 12 28  ab 3b d0 2e 5e 81 47 2a  |..yy...(.;..^.G*|
-00000350  79 1e 16 21 fa 64 78 24  33 24 f7 ac f1 11 a7 15  |y..!.dx$3$......|
-00000360  98 f6 24 52 14 7c 1f 28  0c 24 b1 a9 8a 16 03 03  |..$R.|.(.$......|
+000002c0  ac 0c 00 00 a8 03 00 1d  20 94 54 54 4c 52 a7 a5  |........ .TTLR..|
+000002d0  c0 01 ed 59 bf 46 03 59  25 3b 57 f8 24 99 1b dc  |...Y.F.Y%;W.$...|
+000002e0  f6 f4 1d 42 0e 2e c3 7c  02 08 04 00 80 5a 42 35  |...B...|.....ZB5|
+000002f0  78 c8 a9 37 6f 61 a4 ef  3a a3 12 03 f7 ee 44 be  |x..7oa..:.....D.|
+00000300  8b c9 52 4f de db f5 1e  9c c8 33 32 3c 0a 9e d6  |..RO......32<...|
+00000310  32 bf 2e 12 f7 b0 9b 15  dc eb 24 6e d6 f2 ad 5d  |2.........$n...]|
+00000320  9e 77 c4 a7 7a a1 a0 13  0b 90 b4 aa 3e 51 a1 3d  |.w..z.......>Q.=|
+00000330  71 09 15 84 1c c5 98 bb  12 db 11 e2 4c 2c d1 a9  |q...........L,..|
+00000340  5a ed 8e fb c6 ae ec d5  6d ec d8 d8 2a a7 23 ae  |Z.......m...*.#.|
+00000350  d7 d2 03 d0 23 8a 21 ac  7e 56 b4 23 7f c6 2a 72  |....#.!.~V.#..*r|
+00000360  85 0b 6d 6c 9d 6f ad ee  15 20 d9 2b b9 16 03 03  |..ml.o... .+....|
 00000370  00 3a 0d 00 00 36 03 01  02 40 00 2e 04 03 05 03  |.:...6...@......|
 00000380  06 03 08 07 08 08 08 09  08 0a 08 0b 08 04 08 05  |................|
 00000390  08 06 04 01 05 01 06 01  03 03 02 03 03 01 02 01  |................|
@@ -112,26 +112,26 @@
 00000200  e5 35 16 03 03 00 25 10  00 00 21 20 2f e5 7d a3  |.5....%...! /.}.|
 00000210  47 cd 62 43 15 28 da ac  5f bb 29 07 30 ff f6 84  |G.bC.(.._.).0...|
 00000220  af c4 cf c2 ed 90 99 5f  58 cb 3b 74 16 03 03 00  |......._X.;t....|
-00000230  88 0f 00 00 84 08 04 00  80 8b ad 4b 9a 7a 53 b8  |...........K.zS.|
-00000240  6a 0a e7 71 6a 9b 8b 89  7d 3a 49 c9 af ce 3f e2  |j..qj...}:I...?.|
-00000250  3e cc 0b da 57 9b 8c 2f  58 0f a9 05 4d e9 de 83  |>...W../X...M...|
-00000260  60 e8 1c 77 ef 23 e4 aa  6b c3 15 64 98 f8 b1 72  |`..w.#..k..d...r|
-00000270  b2 8a 9e a3 19 3d 73 84  05 53 59 e1 bb e1 db 51  |.....=s..SY....Q|
-00000280  49 38 cf 8b ee 3c b6 05  0d ba 62 02 b3 36 dc c1  |I8...<....b..6..|
-00000290  e1 52 4d bd 6a c1 3e 55  ff 82 5f e3 7c 84 1c 65  |.RM.j.>U.._.|..e|
-000002a0  45 53 b9 c0 56 99 ac 56  d7 4a fa 72 3e 63 36 06  |ES..V..V.J.r>c6.|
-000002b0  d3 60 ef 34 05 3f 57 20  79 14 03 03 00 01 01 16  |.`.4.?W y.......|
-000002c0  03 03 00 28 00 00 00 00  00 00 00 00 00 26 b7 73  |...(.........&.s|
-000002d0  b5 e9 b3 8a 63 00 9b 36  a0 cf 2a 60 0f 8a 59 75  |....c..6..*`..Yu|
-000002e0  08 71 97 dc 66 73 15 04  08 b4 d3 91              |.q..fs......|
+00000230  88 0f 00 00 84 04 01 00  80 61 11 ba 1a fe 08 7c  |.........a.....||
+00000240  40 68 88 01 a4 3a 46 bf  f6 e9 bb b6 08 92 20 f0  |@h...:F....... .|
+00000250  13 90 c2 4b 53 83 a1 12  c2 d5 8d e6 67 82 df 80  |...KS.......g...|
+00000260  85 a5 b4 e0 cf 1b d6 3a  46 1e 62 e5 7f 21 bc 91  |.......:F.b..!..|
+00000270  4a 8c c0 79 16 64 5f 7e  40 c5 fb 7a 52 5b bf db  |J..y.d_~@..zR[..|
+00000280  cc 31 f8 b8 37 ef df dc  5f 96 30 ad dd 0b 8a 87  |.1..7..._.0.....|
+00000290  af 4d c6 5c a5 5e d7 2e  fa c7 72 68 85 71 c3 0e  |.M.\.^....rh.q..|
+000002a0  1b 26 87 ff 46 47 4a 1b  ce b7 a5 aa 13 d2 5a e3  |.&..FGJ.......Z.|
+000002b0  36 02 35 df 68 d9 bf 3f  24 14 03 03 00 01 01 16  |6.5.h..?$.......|
+000002c0  03 03 00 28 00 00 00 00  00 00 00 00 e3 8e cc e5  |...(............|
+000002d0  2e ab 40 fa 3d 47 c1 4f  3f de 97 a9 3d 96 73 ba  |..@.=G.O?...=.s.|
+000002e0  eb a0 ce 67 f6 d1 14 b8  7e cd 1f 85              |...g....~...|
 >>> Flow 4 (server to client)
-00000000  14 03 03 00 01 01 16 03  03 00 28 d2 b2 3f a8 43  |..........(..?.C|
-00000010  41 1a 85 20 9f ee 21 6a  c5 96 cf 7c 01 8e f6 3a  |A.. ..!j...|...:|
-00000020  e3 29 14 68 ea 74 a3 ef  85 04 78 33 db c7 d4 c9  |.).h.t....x3....|
-00000030  a2 fd 6a                                          |..j|
+00000000  14 03 03 00 01 01 16 03  03 00 28 6a 0a 74 70 75  |..........(j.tpu|
+00000010  0b 39 33 a5 15 0d 7c 7f  f8 13 de 0e 0a 8f 13 3b  |.93...|........;|
+00000020  62 4f 8a 0b bd 0a aa 9b  5a 52 d5 e6 9f e5 b9 3f  |bO......ZR.....?|
+00000030  bd d8 3b                                          |..;|
 >>> Flow 5 (client to server)
-00000000  17 03 03 00 1e 00 00 00  00 00 00 00 01 c3 3b 68  |..............;h|
-00000010  b5 e9 4d 75 22 92 fb 19  85 88 38 97 12 3f ce ca  |..Mu".....8..?..|
-00000020  36 c0 d6 15 03 03 00 1a  00 00 00 00 00 00 00 02  |6...............|
-00000030  c1 a9 03 81 61 04 7c 86  24 e9 90 22 59 6f c7 bc  |....a.|.$.."Yo..|
-00000040  c2 a1                                             |..|
+00000000  17 03 03 00 1e 00 00 00  00 00 00 00 01 0e 4d 62  |..............Mb|
+00000010  d3 ac cd 11 15 6d 24 c7  00 fa f9 d2 91 ba eb 06  |.....m$.........|
+00000020  f2 44 f1 15 03 03 00 1a  00 00 00 00 00 00 00 02  |.D..............|
+00000030  d1 5a 58 ba ae 65 15 67  79 1f 52 f1 1a da 50 99  |.ZX..e.gy.R...P.|
+00000040  e8 50                                             |.P|

src/crypto/tls/testdata/Client-TLSv12-ClientCert-RSA-PSS-Disabled-512

@@ -0,0 +1,125 @@
+>>> Flow 1 (client to server)
+00000000  16 03 01 00 f8 01 00 00  f4 03 03 00 00 00 00 00  |................|
+00000010  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+00000020  00 00 00 00 00 00 00 00  00 00 00 20 00 00 00 00  |........... ....|
+00000030  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+00000040  00 00 00 00 00 00 00 00  00 00 00 00 00 32 cc a8  |.............2..|
+00000050  cc a9 c0 2f c0 2b c0 30  c0 2c c0 27 c0 13 c0 23  |.../.+.0.,.'...#|
+00000060  c0 09 c0 14 c0 0a 00 9c  00 9d 00 3c 00 2f 00 35  |...........<./.5|
+00000070  c0 12 00 0a 00 05 c0 11  c0 07 13 01 13 03 13 02  |................|
+00000080  01 00 00 79 00 05 00 05  01 00 00 00 00 00 0a 00  |...y............|
+00000090  0a 00 08 00 1d 00 17 00  18 00 19 00 0b 00 02 01  |................|
+000000a0  00 00 0d 00 18 00 16 08  04 08 05 08 06 04 01 04  |................|
+000000b0  03 05 01 05 03 06 01 06  03 02 01 02 03 ff 01 00  |................|
+000000c0  01 00 00 12 00 00 00 2b  00 09 08 03 04 03 03 03  |.......+........|
+000000d0  02 03 01 00 33 00 26 00  24 00 1d 00 20 2f e5 7d  |....3.&.$... /.}|
+000000e0  a3 47 cd 62 43 15 28 da  ac 5f bb 29 07 30 ff f6  |.G.bC.(.._.).0..|
+000000f0  84 af c4 cf c2 ed 90 99  5f 58 cb 3b 74           |........_X.;t|
+>>> Flow 2 (server to client)
+00000000  16 03 03 00 59 02 00 00  55 03 03 68 11 23 f1 8d  |....Y...U..h.#..|
+00000010  2b a0 71 8f 6e ad 9f ae  43 58 c2 93 2e f5 01 3d  |+.q.n...CX.....=|
+00000020  15 b6 d6 0d f5 42 25 ca  b7 b4 96 20 00 c7 86 06  |.....B%.... ....|
+00000030  ed d1 23 99 dd e3 c4 f5  f9 31 42 51 a3 51 5a 40  |..#......1BQ.QZ@|
+00000040  11 f6 07 90 51 04 f8 a2  f6 66 c1 f7 c0 2f 00 00  |....Q....f.../..|
+00000050  0d ff 01 00 01 00 00 0b  00 04 03 00 01 02 16 03  |................|
+00000060  03 02 59 0b 00 02 55 00  02 52 00 02 4f 30 82 02  |..Y...U..R..O0..|
+00000070  4b 30 82 01 b4 a0 03 02  01 02 02 09 00 e8 f0 9d  |K0..............|
+00000080  3f e2 5b ea a6 30 0d 06  09 2a 86 48 86 f7 0d 01  |?.[..0...*.H....|
+00000090  01 0b 05 00 30 1f 31 0b  30 09 06 03 55 04 0a 13  |....0.1.0...U...|
+000000a0  02 47 6f 31 10 30 0e 06  03 55 04 03 13 07 47 6f  |.Go1.0...U....Go|
+000000b0  20 52 6f 6f 74 30 1e 17  0d 31 36 30 31 30 31 30  | Root0...1601010|
+000000c0  30 30 30 30 30 5a 17 0d  32 35 30 31 30 31 30 30  |00000Z..25010100|
+000000d0  30 30 30 30 5a 30 1a 31  0b 30 09 06 03 55 04 0a  |0000Z0.1.0...U..|
+000000e0  13 02 47 6f 31 0b 30 09  06 03 55 04 03 13 02 47  |..Go1.0...U....G|
+000000f0  6f 30 81 9f 30 0d 06 09  2a 86 48 86 f7 0d 01 01  |o0..0...*.H.....|
+00000100  01 05 00 03 81 8d 00 30  81 89 02 81 81 00 db 46  |.......0.......F|
+00000110  7d 93 2e 12 27 06 48 bc  06 28 21 ab 7e c4 b6 a2  |}...'.H..(!.~...|
+00000120  5d fe 1e 52 45 88 7a 36  47 a5 08 0d 92 42 5b c2  |]..RE.z6G....B[.|
+00000130  81 c0 be 97 79 98 40 fb  4f 6d 14 fd 2b 13 8b c2  |....y.@.Om..+...|
+00000140  a5 2e 67 d8 d4 09 9e d6  22 38 b7 4a 0b 74 73 2b  |..g....."8.J.ts+|
+00000150  c2 34 f1 d1 93 e5 96 d9  74 7b f3 58 9f 6c 61 3c  |.4......t{.X.la<|
+00000160  c0 b0 41 d4 d9 2b 2b 24  23 77 5b 1c 3b bd 75 5d  |..A..++$#w[.;.u]|
+00000170  ce 20 54 cf a1 63 87 1d  1e 24 c4 f3 1d 1a 50 8b  |. T..c...$....P.|
+00000180  aa b6 14 43 ed 97 a7 75  62 f4 14 c8 52 d7 02 03  |...C...ub...R...|
+00000190  01 00 01 a3 81 93 30 81  90 30 0e 06 03 55 1d 0f  |......0..0...U..|
+000001a0  01 01 ff 04 04 03 02 05  a0 30 1d 06 03 55 1d 25  |.........0...U.%|
+000001b0  04 16 30 14 06 08 2b 06  01 05 05 07 03 01 06 08  |..0...+.........|
+000001c0  2b 06 01 05 05 07 03 02  30 0c 06 03 55 1d 13 01  |+.......0...U...|
+000001d0  01 ff 04 02 30 00 30 19  06 03 55 1d 0e 04 12 04  |....0.0...U.....|
+000001e0  10 9f 91 16 1f 43 43 3e  49 a6 de 6d b6 80 d7 9f  |.....CC>I..m....|
+000001f0  60 30 1b 06 03 55 1d 23  04 14 30 12 80 10 48 13  |`0...U.#..0...H.|
+00000200  49 4d 13 7e 16 31 bb a3  01 d5 ac ab 6e 7b 30 19  |IM.~.1......n{0.|
+00000210  06 03 55 1d 11 04 12 30  10 82 0e 65 78 61 6d 70  |..U....0...examp|
+00000220  6c 65 2e 67 6f 6c 61 6e  67 30 0d 06 09 2a 86 48  |le.golang0...*.H|
+00000230  86 f7 0d 01 01 0b 05 00  03 81 81 00 9d 30 cc 40  |.............0.@|
+00000240  2b 5b 50 a0 61 cb ba e5  53 58 e1 ed 83 28 a9 58  |+[P.a...SX...(.X|
+00000250  1a a9 38 a4 95 a1 ac 31  5a 1a 84 66 3d 43 d3 2d  |..8....1Z..f=C.-|
+00000260  d9 0b f2 97 df d3 20 64  38 92 24 3a 00 bc cf 9c  |...... d8.$:....|
+00000270  7d b7 40 20 01 5f aa d3  16 61 09 a2 76 fd 13 c3  |}.@ ._...a..v...|
+00000280  cc e1 0c 5c ee b1 87 82  f1 6c 04 ed 73 bb b3 43  |...\.....l..s..C|
+00000290  77 8d 0c 1c f1 0f a1 d8  40 83 61 c9 4c 72 2b 9d  |w.......@.a.Lr+.|
+000002a0  ae db 46 06 06 4d f4 c1  b3 3e c0 d1 bd 42 d4 db  |..F..M...>...B..|
+000002b0  fe 3d 13 60 84 5c 21 d3  3b e9 fa e7 16 03 03 00  |.=.`.\!.;.......|
+000002c0  ac 0c 00 00 a8 03 00 1d  20 fe 68 1c bf 2b d7 75  |........ .h..+.u|
+000002d0  c2 dd 96 03 5d 77 61 c1  7d dd 6f bc ea 3c aa 27  |....]wa.}.o..<.'|
+000002e0  ba cf 93 e2 8b d8 66 a1  1c 08 04 00 80 5e 16 b9  |......f......^..|
+000002f0  53 17 7d 8d bb 46 4b 1f  37 be cd fe e1 45 c3 10  |S.}..FK.7....E..|
+00000300  68 54 e4 61 20 a5 a5 98  4b df a7 5d 41 4a aa f8  |hT.a ...K..]AJ..|
+00000310  0e 36 c2 02 a6 56 a9 f1  aa 76 86 fd a7 86 fb 06  |.6...V...v......|
+00000320  94 55 56 bd eb 57 10 9a  d5 ba 70 59 46 75 e3 b3  |.UV..W....pYFu..|
+00000330  29 14 c2 65 0e 5c a1 47  e6 bf 12 9d 31 8f 65 4d  |)..e.\.G....1.eM|
+00000340  af dc 1b 6e d2 de d7 fb  85 e7 5a 42 4f de bf d8  |...n......ZBO...|
+00000350  d5 d8 5c 95 71 27 e7 04  af 58 0a d8 77 fb 3d 22  |..\.q'...X..w.="|
+00000360  84 f6 f6 53 c0 79 7a 72  01 6e 5c e1 a8 16 03 03  |...S.yzr.n\.....|
+00000370  00 3a 0d 00 00 36 03 01  02 40 00 2e 04 03 05 03  |.:...6...@......|
+00000380  06 03 08 07 08 08 08 09  08 0a 08 0b 08 04 08 05  |................|
+00000390  08 06 04 01 05 01 06 01  03 03 02 03 03 01 02 01  |................|
+000003a0  03 02 02 02 04 02 05 02  06 02 00 00 16 03 03 00  |................|
+000003b0  04 0e 00 00 00                                    |.....|
+>>> Flow 3 (client to server)
+00000000  16 03 03 01 7f 0b 00 01  7b 00 01 78 00 01 75 30  |........{..x..u0|
+00000010  82 01 71 30 82 01 1b a0  03 02 01 02 02 10 1a 34  |..q0...........4|
+00000020  27 90 21 65 52 a6 85 96  de a2 c7 2c ff b4 30 0d  |'.!eR......,..0.|
+00000030  06 09 2a 86 48 86 f7 0d  01 01 0b 05 00 30 12 31  |..*.H........0.1|
+00000040  10 30 0e 06 03 55 04 0a  13 07 41 63 6d 65 20 43  |.0...U....Acme C|
+00000050  6f 30 1e 17 0d 31 39 30  31 31 38 32 33 32 33 32  |o0...19011823232|
+00000060  38 5a 17 0d 32 30 30 31  31 38 32 33 32 33 32 38  |8Z..200118232328|
+00000070  5a 30 12 31 10 30 0e 06  03 55 04 0a 13 07 41 63  |Z0.1.0...U....Ac|
+00000080  6d 65 20 43 6f 30 5c 30  0d 06 09 2a 86 48 86 f7  |me Co0\0...*.H..|
+00000090  0d 01 01 01 05 00 03 4b  00 30 48 02 41 00 dd 7b  |.......K.0H.A..{|
+000000a0  3d 6b 15 40 f0 6b 1d 87  4f 16 dc 9c 55 0f f4 08  |=k.@.k..O...U...|
+000000b0  5c 80 41 8c 1d 55 76 9e  7e 15 54 45 85 24 1e 88  |\.A..Uv.~.TE.$..|
+000000c0  f0 2f cd 93 1d 17 cb 24  25 ae 61 58 07 31 10 9c  |./.....$%.aX.1..|
+000000d0  83 e1 2a 5b 38 4f 48 45  a0 bb e3 26 75 e9 02 03  |..*[8OHE...&u...|
+000000e0  01 00 01 a3 4d 30 4b 30  0e 06 03 55 1d 0f 01 01  |....M0K0...U....|
+000000f0  ff 04 04 03 02 05 a0 30  13 06 03 55 1d 25 04 0c  |.......0...U.%..|
+00000100  30 0a 06 08 2b 06 01 05  05 07 03 01 30 0c 06 03  |0...+.......0...|
+00000110  55 1d 13 01 01 ff 04 02  30 00 30 16 06 03 55 1d  |U.......0.0...U.|
+00000120  11 04 0f 30 0d 82 0b 65  78 61 6d 70 6c 65 2e 63  |...0...example.c|
+00000130  6f 6d 30 0d 06 09 2a 86  48 86 f7 0d 01 01 0b 05  |om0...*.H.......|
+00000140  00 03 41 00 c4 3b 94 4b  e0 6b ad 2d dc fa 1f a4  |..A..;.K.k.-....|
+00000150  f9 f4 0f 3a 63 92 73 2e  b2 4d 7f 66 1f 0d 10 29  |...:c.s..M.f...)|
+00000160  bb 9c 19 a9 97 60 4c b4  51 12 30 39 d3 b4 b5 0d  |.....`L.Q.09....|
+00000170  cb 1c f7 35 60 6b d8 48  fc 24 0e 39 23 a8 40 ac  |...5`k.H.$.9#.@.|
+00000180  d9 59 bf 00 16 03 03 00  25 10 00 00 21 20 2f e5  |.Y......%...! /.|
+00000190  7d a3 47 cd 62 43 15 28  da ac 5f bb 29 07 30 ff  |}.G.bC.(.._.).0.|
+000001a0  f6 84 af c4 cf c2 ed 90  99 5f 58 cb 3b 74 16 03  |........._X.;t..|
+000001b0  03 00 48 0f 00 00 44 04  01 00 40 15 33 b2 27 d6  |..H...D...@.3.'.|
+000001c0  ad 7f 45 86 df a0 83 5e  7c fb a7 0e 04 8e 3c a1  |..E....^|.....<.|
+000001d0  5b 9a 8f 98 04 cf 66 bb  cf 6a d4 63 d7 ff b2 a4  |[.....f..j.c....|
+000001e0  f1 08 27 f7 53 1c ec 76  35 b1 09 93 91 db 63 e3  |..'.S..v5.....c.|
+000001f0  a6 2b e5 55 da 06 5b 2f  c7 8d c3 14 03 03 00 01  |.+.U..[/........|
+00000200  01 16 03 03 00 28 00 00  00 00 00 00 00 00 98 d8  |.....(..........|
+00000210  99 fa 5a fb 79 57 1f 02  4e 07 51 d6 c6 32 9c e8  |..Z.yW..N.Q..2..|
+00000220  54 50 6c f9 63 fb 38 e2  ef 88 4b 7e 8d 7a        |TPl.c.8...K~.z|
+>>> Flow 4 (server to client)
+00000000  14 03 03 00 01 01 16 03  03 00 28 4c 6b f0 26 84  |..........(Lk.&.|
+00000010  97 e6 54 cf 1f 25 1c 91  5d 10 63 22 66 73 d2 ce  |..T..%..].c"fs..|
+00000020  0d 7c 0b 3d 7d 31 3c 0b  6c be 30 72 9e 04 c0 fb  |.|.=}1<.l.0r....|
+00000030  73 88 75                                          |s.u|
+>>> Flow 5 (client to server)
+00000000  17 03 03 00 1e 00 00 00  00 00 00 00 01 2a b2 2d  |.............*.-|
+00000010  7f 6e 12 2d d7 63 05 e8  c4 fd 81 de b6 65 2f 2b  |.n.-.c.......e/+|
+00000020  00 0e 13 15 03 03 00 1a  00 00 00 00 00 00 00 02  |................|
+00000030  9c c0 ae 5a b4 5f b5 4f  cd 3f 27 78 f9 b3 b5 b5  |...Z._.O.?'x....|
+00000040  57 f2                                             |W.|

src/crypto/tls/tls.go

@@ -4,6 +4,15 @@
 
 // Package tls partially implements TLS 1.2, as specified in RFC 5246,
 // and TLS 1.3, as specified in RFC 8446.
+//
+// TLS 1.3 is available only on an opt-in basis in Go 1.12. To enable
+// it, set the GODEBUG environment variable (comma-separated key=value
+// options) such that it includes "tls13=1". To enable it from within
+// the process, set the environment variable before any use of TLS:
+//
+//     func init() {
+//         os.Setenv("GODEBUG", os.Getenv("GODEBUG")+",tls13=1")
+//     }
 package tls
 
 // BUG(agl): The crypto/tls package only implements some countermeasures

src/crypto/tls/tls_test.go

@@ -370,47 +370,6 @@ func TestVerifyHostname(t *testing.T) {
 	}
 }
 
-func TestVerifyHostnameResumed(t *testing.T) {
-	t.Run("TLSv12", func(t *testing.T) { testVerifyHostnameResumed(t, VersionTLS12) })
-	t.Run("TLSv13", func(t *testing.T) { testVerifyHostnameResumed(t, VersionTLS13) })
-}
-
-func testVerifyHostnameResumed(t *testing.T, version uint16) {
-	testenv.MustHaveExternalNetwork(t)
-
-	config := &Config{
-		MaxVersion:         version,
-		ClientSessionCache: NewLRUClientSessionCache(32),
-	}
-	for i := 0; i < 2; i++ {
-		c, err := Dial("tcp", "mail.google.com:https", config)
-		if err != nil {
-			t.Fatalf("Dial #%d: %v", i, err)
-		}
-		cs := c.ConnectionState()
-		if i > 0 && !cs.DidResume {
-			t.Fatalf("Subsequent connection unexpectedly didn't resume")
-		}
-		if cs.Version != version {
-			t.Fatalf("Unexpectedly negotiated version %x", cs.Version)
-		}
-		if cs.VerifiedChains == nil {
-			t.Fatalf("Dial #%d: cs.VerifiedChains == nil", i)
-		}
-		if err := c.VerifyHostname("mail.google.com"); err != nil {
-			t.Fatalf("verify mail.google.com #%d: %v", i, err)
-		}
-		// Give the client a chance to read the server session tickets.
-		c.SetReadDeadline(time.Now().Add(500 * time.Millisecond))
-		if _, err := c.Read(make([]byte, 1)); err != nil {
-			if err, ok := err.(net.Error); !ok || !err.Timeout() {
-				t.Fatal(err)
-			}
-		}
-		c.Close()
-	}
-}
-
 func TestConnCloseBreakingWrite(t *testing.T) {
 	ln := newLocalListener(t)
 	defer ln.Close()

src/crypto/x509/root_cgo_darwin.go

@@ -16,7 +16,7 @@ package x509
 #include <CoreFoundation/CoreFoundation.h>
 #include <Security/Security.h>
 
-static bool isSSLPolicy(SecPolicyRef policyRef) {
+static Boolean isSSLPolicy(SecPolicyRef policyRef) {
 	if (!policyRef) {
 		return false;
 	}
@@ -24,13 +24,13 @@ static bool isSSLPolicy(SecPolicyRef policyRef) {
 	if (properties == NULL) {
 		return false;
 	}
+	Boolean isSSL = false;
 	CFTypeRef value = NULL;
 	if (CFDictionaryGetValueIfPresent(properties, kSecPolicyOid, (const void **)&value)) {
-		CFRelease(properties);
-		return CFEqual(value, kSecPolicyAppleSSL);
+		isSSL = CFEqual(value, kSecPolicyAppleSSL);
 	}
 	CFRelease(properties);
-	return false;
+	return isSSL;
 }
 
 // sslTrustSettingsResult obtains the final kSecTrustSettingsResult value

src/database/sql/driver/driver.go

@@ -137,7 +137,7 @@ type Pinger interface {
 
 // Execer is an optional interface that may be implemented by a Conn.
 //
-// If a Conn implements neither ExecerContext nor Execer Execer,
+// If a Conn implements neither ExecerContext nor Execer,
 // the sql package's DB.Exec will first prepare a query, execute the statement,
 // and then close the statement.
 //

src/internal/fmtsort/sort.go

@@ -167,7 +167,7 @@ func compare(aVal, bVal reflect.Value) int {
 		if c, ok := nilCompare(aVal, bVal); ok {
 			return c
 		}
-		c := compare(reflect.ValueOf(aType), reflect.ValueOf(bType))
+		c := compare(reflect.ValueOf(aVal.Elem().Type()), reflect.ValueOf(bVal.Elem().Type()))
 		if c != 0 {
 			return c
 		}

src/internal/fmtsort/sort_test.go

@@ -126,10 +126,6 @@ var sortTests = []sortTest{
 		map[[2]int]string{{7, 2}: "72", {7, 1}: "71", {3, 4}: "34"},
 		"[3 4]:34 [7 1]:71 [7 2]:72",
 	},
-	{
-		map[interface{}]string{7: "7", 4: "4", 3: "3", nil: "nil"},
-		"<nil>:nil 3:3 4:4 7:7",
-	},
 }
 
 func sprint(data interface{}) string {
@@ -210,3 +206,41 @@ func TestOrder(t *testing.T) {
 		}
 	}
 }
+
+func TestInterface(t *testing.T) {
+	// A map containing multiple concrete types should be sorted by type,
+	// then value. However, the relative ordering of types is unspecified,
+	// so test this by checking the presence of sorted subgroups.
+	m := map[interface{}]string{
+		[2]int{1, 0}:             "",
+		[2]int{0, 1}:             "",
+		true:                     "",
+		false:                    "",
+		3.1:                      "",
+		2.1:                      "",
+		1.1:                      "",
+		math.NaN():               "",
+		3:                        "",
+		2:                        "",
+		1:                        "",
+		"c":                      "",
+		"b":                      "",
+		"a":                      "",
+		struct{ x, y int }{1, 0}: "",
+		struct{ x, y int }{0, 1}: "",
+	}
+	got := sprint(m)
+	typeGroups := []string{
+		"NaN: 1.1: 2.1: 3.1:", // float64
+		"false: true:",        // bool
+		"1: 2: 3:",            // int
+		"a: b: c:",            // string
+		"[0 1]: [1 0]:",       // [2]int
+		"{0 1}: {1 0}:",       // struct{ x int; y int }
+	}
+	for _, g := range typeGroups {
+		if !strings.Contains(got, g) {
+			t.Errorf("sorted map should contain %q", g)
+		}
+	}
+}

src/internal/poll/fd_windows.go

@@ -660,6 +660,10 @@ func (fd *FD) Write(buf []byte) (int, error) {
 		return 0, err
 	}
 	defer fd.writeUnlock()
+	if fd.isFile || fd.isDir || fd.isConsole {
+		fd.l.Lock()
+		defer fd.l.Unlock()
+	}
 
 	ntotal := 0
 	for len(buf) > 0 {
@@ -670,8 +674,6 @@ func (fd *FD) Write(buf []byte) (int, error) {
 		var n int
 		var err error
 		if fd.isFile || fd.isDir || fd.isConsole {
-			fd.l.Lock()
-			defer fd.l.Unlock()
 			if fd.isConsole {
 				n, err = fd.writeConsole(b)
 			} else {

src/internal/syscall/windows/syscall_windows.go

@@ -305,3 +305,6 @@ const (
 func LoadGetFinalPathNameByHandle() error {
 	return procGetFinalPathNameByHandleW.Find()
 }
+
+//sys	CreateEnvironmentBlock(block **uint16, token syscall.Token, inheritExisting bool) (err error) = userenv.CreateEnvironmentBlock
+//sys	DestroyEnvironmentBlock(block *uint16) (err error) = userenv.DestroyEnvironmentBlock

src/internal/syscall/windows/zsyscall_windows.go

@@ -58,6 +58,8 @@ var (
 	procNetShareAdd                  = modnetapi32.NewProc("NetShareAdd")
 	procNetShareDel                  = modnetapi32.NewProc("NetShareDel")
 	procGetFinalPathNameByHandleW    = modkernel32.NewProc("GetFinalPathNameByHandleW")
+	procCreateEnvironmentBlock       = moduserenv.NewProc("CreateEnvironmentBlock")
+	procDestroyEnvironmentBlock      = moduserenv.NewProc("DestroyEnvironmentBlock")
 	procImpersonateSelf              = modadvapi32.NewProc("ImpersonateSelf")
 	procRevertToSelf                 = modadvapi32.NewProc("RevertToSelf")
 	procOpenThreadToken              = modadvapi32.NewProc("OpenThreadToken")
@@ -220,6 +222,36 @@ func GetFinalPathNameByHandle(file syscall.Handle, filePath *uint16, filePathSiz
 	return
 }
 
+func CreateEnvironmentBlock(block **uint16, token syscall.Token, inheritExisting bool) (err error) {
+	var _p0 uint32
+	if inheritExisting {
+		_p0 = 1
+	} else {
+		_p0 = 0
+	}
+	r1, _, e1 := syscall.Syscall(procCreateEnvironmentBlock.Addr(), 3, uintptr(unsafe.Pointer(block)), uintptr(token), uintptr(_p0))
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func DestroyEnvironmentBlock(block *uint16) (err error) {
+	r1, _, e1 := syscall.Syscall(procDestroyEnvironmentBlock.Addr(), 1, uintptr(unsafe.Pointer(block)), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
 func ImpersonateSelf(impersonationlevel uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procImpersonateSelf.Addr(), 1, uintptr(impersonationlevel), 0, 0)
 	if r1 == 0 {

src/math/big/arith_arm64.s

@@ -194,83 +194,97 @@ len0:
 	MOVD	R2, c+56(FP)
 	RET
 
-
 // func shlVU(z, x []Word, s uint) (c Word)
+// This implementation handles the shift operation from the high word to the low word,
+// which may be an error for the case where the low word of x overlaps with the high
+// word of z. When calling this function directly, you need to pay attention to this
+// situation.
 TEXT ·shlVU(SB),NOSPLIT,$0
-	MOVD	z+0(FP), R0
-	MOVD	z_len+8(FP), R1
+	LDP	z+0(FP), (R0, R1)	// R0 = z.ptr, R1 = len(z)
 	MOVD	x+24(FP), R2
 	MOVD	s+48(FP), R3
-	MOVD	$0, R8		// in order not to affect the first element, R8 is initialized to zero
-	MOVD	$64, R4
-	SUB	R3, R4
+	ADD	R1<<3, R0	// R0 = &z[n]
+	ADD	R1<<3, R2	// R2 = &x[n]
 	CBZ	R1, len0
 	CBZ	R3, copy	// if the number of shift is 0, just copy x to z
-
-	TBZ	$0, R1, two
-	MOVD.P	8(R2), R6
-	LSR	R4, R6, R8
-	LSL	R3, R6
-	MOVD.P	R6, 8(R0)
+	MOVD	$64, R4
+	SUB	R3, R4
+	// handling the most significant element x[n-1]
+	MOVD.W	-8(R2), R6
+	LSR	R4, R6, R5	// return value
+	LSL	R3, R6, R8	// x[i] << s
 	SUB	$1, R1
+one:	TBZ	$0, R1, two
+	MOVD.W	-8(R2), R6
+	LSR	R4, R6, R7
+	ORR	R8, R7
+	LSL	R3, R6, R8
+	SUB	$1, R1
+	MOVD.W	R7, -8(R0)
 two:
 	TBZ	$1, R1, loop
-	LDP.P	16(R2), (R6, R7)
-	LSR	R4, R6, R9
-	LSL	R3, R6
-	ORR	R8, R6
-	LSR	R4, R7, R8
+	LDP.W	-16(R2), (R6, R7)
+	LSR	R4, R7, R10
+	ORR	R8, R10
 	LSL	R3, R7
-	ORR	R9, R7
-	STP.P	(R6, R7), 16(R0)
+	LSR	R4, R6, R9
+	ORR	R7, R9
+	LSL	R3, R6, R8
 	SUB	$2, R1
+	STP.W	(R9, R10), -16(R0)
 loop:
 	CBZ	R1, done
-	LDP.P	32(R2), (R10, R11)
-	LDP	-16(R2), (R12, R13)
-	LSR	R4, R10, R20
-	LSL	R3, R10
-	ORR	R8, R10		// z[i] = (x[i] << s) | (x[i-1] >> (64 - s))
-	LSR	R4, R11, R21
-	LSL	R3, R11
-	ORR	R20, R11
-	LSR	R4, R12, R22
-	LSL	R3, R12
-	ORR	R21, R12
-	LSR	R4, R13, R8
+	LDP.W	-32(R2), (R10, R11)
+	LDP	16(R2), (R12, R13)
+	LSR	R4, R13, R23
+	ORR	R8, R23		// z[i] = (x[i] << s) | (x[i-1] >> (64 - s))
 	LSL	R3, R13
-	ORR	R22, R13
-	STP.P	(R10, R11), 32(R0)
-	STP	(R12, R13), -16(R0)
+	LSR	R4, R12, R22
+	ORR	R13, R22
+	LSL	R3, R12
+	LSR	R4, R11, R21
+	ORR	R12, R21
+	LSL	R3, R11
+	LSR	R4, R10, R20
+	ORR	R11, R20
+	LSL	R3, R10, R8
+	STP.W	(R20, R21), -32(R0)
+	STP	(R22, R23), 16(R0)
 	SUB	$4, R1
 	B	loop
 done:
-	MOVD	R8, c+56(FP)	// the part moved out from the last element
+	MOVD.W	R8, -8(R0)	// the first element x[0]
+	MOVD	R5, c+56(FP)	// the part moved out from x[n-1]
 	RET
 copy:
+	CMP	R0, R2
+	BEQ	len0
 	TBZ	$0, R1, ctwo
-	MOVD.P	8(R2), R3
-	MOVD.P	R3, 8(R0)
+	MOVD.W	-8(R2), R4
+	MOVD.W	R4, -8(R0)
 	SUB	$1, R1
 ctwo:
 	TBZ	$1, R1, cloop
-	LDP.P	16(R2), (R4, R5)
-	STP.P	(R4, R5), 16(R0)
+	LDP.W	-16(R2), (R4, R5)
+	STP.W	(R4, R5), -16(R0)
 	SUB	$2, R1
 cloop:
 	CBZ	R1, len0
-	LDP.P	32(R2), (R4, R5)
-	LDP	-16(R2), (R6, R7)
-	STP.P	(R4, R5), 32(R0)
-	STP	(R6, R7), -16(R0)
+	LDP.W	-32(R2), (R4, R5)
+	LDP	16(R2), (R6, R7)
+	STP.W	(R4, R5), -32(R0)
+	STP	(R6, R7), 16(R0)
 	SUB	$4, R1
 	B	cloop
 len0:
 	MOVD	$0, c+56(FP)
 	RET
 
-
 // func shrVU(z, x []Word, s uint) (c Word)
+// This implementation handles the shift operation from the low word to the high word,
+// which may be an error for the case where the high word of x overlaps with the low
+// word of z. When calling this function directly, you need to pay attention to this
+// situation.
 TEXT ·shrVU(SB),NOSPLIT,$0
 	MOVD	z+0(FP), R0
 	MOVD	z_len+8(FP), R1
@@ -330,6 +344,8 @@ done:
 	MOVD	R8, (R0)	// deal with the last element
 	RET
 copy:
+	CMP	R0, R2
+	BEQ	len0
 	TBZ	$0, R1, ctwo
 	MOVD.P	8(R2), R3
 	MOVD.P	R3, 8(R0)

src/math/big/arith_test.go

@@ -255,6 +255,75 @@ func TestFunVW(t *testing.T) {
 	}
 }
 
+type argVU struct {
+	d  []Word // d is a Word slice, the input parameters x and z come from this array.
+	l  uint   // l is the length of the input parameters x and z.
+	xp uint   // xp is the starting position of the input parameter x, x := d[xp:xp+l].
+	zp uint   // zp is the starting position of the input parameter z, z := d[zp:zp+l].
+	s  uint   // s is the shift number.
+	r  []Word // r is the expected output result z.
+	c  Word   // c is the expected return value.
+	m  string // message.
+}
+
+var argshlVU = []argVU{
+	// test cases for shlVU
+	{[]Word{1, _M, _M, _M, _M, _M, 3 << (_W - 2), 0}, 7, 0, 0, 1, []Word{2, _M - 1, _M, _M, _M, _M, 1<<(_W-1) + 1}, 1, "complete overlap of shlVU"},
+	{[]Word{1, _M, _M, _M, _M, _M, 3 << (_W - 2), 0, 0, 0, 0}, 7, 0, 3, 1, []Word{2, _M - 1, _M, _M, _M, _M, 1<<(_W-1) + 1}, 1, "partial overlap by half of shlVU"},
+	{[]Word{1, _M, _M, _M, _M, _M, 3 << (_W - 2), 0, 0, 0, 0, 0, 0, 0}, 7, 0, 6, 1, []Word{2, _M - 1, _M, _M, _M, _M, 1<<(_W-1) + 1}, 1, "partial overlap by 1 Word of shlVU"},
+	{[]Word{1, _M, _M, _M, _M, _M, 3 << (_W - 2), 0, 0, 0, 0, 0, 0, 0, 0}, 7, 0, 7, 1, []Word{2, _M - 1, _M, _M, _M, _M, 1<<(_W-1) + 1}, 1, "no overlap of shlVU"},
+}
+
+var argshrVU = []argVU{
+	// test cases for shrVU
+	{[]Word{0, 3, _M, _M, _M, _M, _M, 1 << (_W - 1)}, 7, 1, 1, 1, []Word{1<<(_W-1) + 1, _M, _M, _M, _M, _M >> 1, 1 << (_W - 2)}, 1 << (_W - 1), "complete overlap of shrVU"},
+	{[]Word{0, 0, 0, 0, 3, _M, _M, _M, _M, _M, 1 << (_W - 1)}, 7, 4, 1, 1, []Word{1<<(_W-1) + 1, _M, _M, _M, _M, _M >> 1, 1 << (_W - 2)}, 1 << (_W - 1), "partial overlap by half of shrVU"},
+	{[]Word{0, 0, 0, 0, 0, 0, 0, 3, _M, _M, _M, _M, _M, 1 << (_W - 1)}, 7, 7, 1, 1, []Word{1<<(_W-1) + 1, _M, _M, _M, _M, _M >> 1, 1 << (_W - 2)}, 1 << (_W - 1), "partial overlap by 1 Word of shrVU"},
+	{[]Word{0, 0, 0, 0, 0, 0, 0, 0, 3, _M, _M, _M, _M, _M, 1 << (_W - 1)}, 7, 8, 1, 1, []Word{1<<(_W-1) + 1, _M, _M, _M, _M, _M >> 1, 1 << (_W - 2)}, 1 << (_W - 1), "no overlap of shrVU"},
+}
+
+func testShiftFunc(t *testing.T, f func(z, x []Word, s uint) Word, a argVU) {
+	// save a.d for error message, or it will be overwritten.
+	b := make([]Word, len(a.d))
+	copy(b, a.d)
+	z := a.d[a.zp : a.zp+a.l]
+	x := a.d[a.xp : a.xp+a.l]
+	c := f(z, x, a.s)
+	for i, zi := range z {
+		if zi != a.r[i] {
+			t.Errorf("d := %v, %s(d[%d:%d], d[%d:%d], %d)\n\tgot z[%d] = %#x; want %#x", b, a.m, a.zp, a.zp+a.l, a.xp, a.xp+a.l, a.s, i, zi, a.r[i])
+			break
+		}
+	}
+	if c != a.c {
+		t.Errorf("d := %v, %s(d[%d:%d], d[%d:%d], %d)\n\tgot c = %#x; want %#x", b, a.m, a.zp, a.zp+a.l, a.xp, a.xp+a.l, a.s, c, a.c)
+	}
+}
+
+func TestShiftOverlap(t *testing.T) {
+	for _, a := range argshlVU {
+		arg := a
+		testShiftFunc(t, shlVU, arg)
+	}
+
+	for _, a := range argshrVU {
+		arg := a
+		testShiftFunc(t, shrVU, arg)
+	}
+}
+
+func TestIssue31084(t *testing.T) {
+	// compute 10^n via 5^n << n.
+	const n = 165
+	p := nat(nil).expNN(nat{5}, nat{n}, nil)
+	p = p.shl(p, uint(n))
+	got := string(p.utoa(10))
+	want := "1" + strings.Repeat("0", n)
+	if got != want {
+		t.Errorf("shl(%v, %v)\n\tgot %s; want %s\n", p, uint(n), got, want)
+	}
+}
+
 func BenchmarkAddVW(b *testing.B) {
 	for _, n := range benchSizes {
 		if isRaceBuilder && n > 1e3 {