[release-branch.go1.8] go1.8rc3

Change-Id: Ie306bb5355f56113356fc141f3c1a56872b39f9e
Reviewed-on: https://go-review.googlesource.com/35836
Reviewed-by: Chris Broadfoot <cbro@golang.org>

README.md

@@ -5,39 +5,37 @@ reliable, and efficient software.
 
 ![Gopher image](doc/gopher/fiveyears.jpg)
 
-For documentation about how to install and use Go,
-visit https://golang.org/ or load doc/install-source.html
-in your web browser.
-
 Our canonical Git repository is located at https://go.googlesource.com/go.
 There is a mirror of the repository at https://github.com/golang/go.
 
+Unless otherwise noted, the Go source files are distributed under the
+BSD-style license found in the LICENSE file.
+
+### Download and Install
+
+#### Binary Distributions
+
+Official binary distributions are available at https://golang.org/dl/.
+
+After downloading a binary release, visit https://golang.org/doc/install
+or load doc/install.html in your web browser for installation
+instructions.
+
+#### Install From Source
+
+If a binary distribution is not available for your combination of
+operating system and architecture, visit
+https://golang.org/doc/install/source or load doc/install-source.html
+in your web browser for source installation instructions.
+
+### Contributing
+
 Go is the work of hundreds of contributors. We appreciate your help!
 
 To contribute, please read the contribution guidelines:
 	https://golang.org/doc/contribute.html
 
-##### Note that we do not accept pull requests and that we use the issue tracker for bug reports and proposals only. Please ask questions on https://forum.golangbridge.org or https://groups.google.com/forum/#!forum/golang-nuts.
-
-Unless otherwise noted, the Go source files are distributed
-under the BSD-style license found in the LICENSE file.
-
---
-
-## Binary Distribution Notes
-
-If you have just untarred a binary Go distribution, you need to set
-the environment variable $GOROOT to the full path of the go
-directory (the one containing this file).  You can omit the
-variable if you unpack it into /usr/local/go, or if you rebuild
-from sources by running all.bash (see doc/install-source.html).
-You should also add the Go binary directory $GOROOT/bin
-to your shell's path.
-
-For example, if you extracted the tar file into $HOME/go, you might
-put the following in your .profile:
-
-	export GOROOT=$HOME/go
-	export PATH=$PATH:$GOROOT/bin
-
-See https://golang.org/doc/install or doc/install.html for more details.
+Note that the Go project does not use GitHub pull requests, and that
+we use the issue tracker for bug reports and proposals only. See
+https://golang.org/wiki/Questions for a list of places to ask
+questions about the Go language.

VERSION

@@ -0,0 +1 @@
+go1.8rc3

doc/contribute.html

@@ -698,7 +698,7 @@ These files will be periodically updated based on the commit logs.
 <p>Code that you contribute should use the standard copyright header:</p>
 
 <pre>
-// Copyright 2016 The Go Authors. All rights reserved.
+// Copyright 2017 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.
 </pre>

doc/debugging_with_gdb.html

@@ -4,7 +4,8 @@
 }-->
 
 <p><i>
-This applies to the <code>gc</code> toolchain. Gccgo has native gdb support.
+This applies to the standard toolchain (the <code>gc</code> Go
+compiler and tools). Gccgo has native gdb support.
 Besides this overview you might want to consult the
 <a href="http://sourceware.org/gdb/current/onlinedocs/gdb/">GDB manual</a>.
 </i></p>
@@ -49,6 +50,14 @@ when debugging, pass the flags <code>-gcflags "-N -l"</code> to the
 debugged.
 </p>
 
+<p>
+If you want to use gdb to inspect a core dump, you can trigger a dump
+on a program crash, on systems that permit it, by setting
+<code>GOTRACEBACK=crash</code> in the environment (see the
+<a href="/pkg/runtime/#hdr-Environment_Variables"> runtime package
+documentation</a> for more info).
+</p>
+
 <h3 id="Common_Operations">Common Operations</h3>
 
 <ul>
@@ -130,7 +139,7 @@ the DWARF code.
 
 <p>
 If you're interested in what the debugging information looks like, run
-'<code>objdump -W 6.out</code>' and browse through the <code>.debug_*</code>
+'<code>objdump -W a.out</code>' and browse through the <code>.debug_*</code>
 sections.
 </p>
 
@@ -377,7 +386,9 @@ $3 = struct hchan&lt;*testing.T&gt;
 </pre>
 
 <p>
-That <code>struct hchan&lt;*testing.T&gt;</code> is the runtime-internal representation of a channel.  It is currently empty, or gdb would have pretty-printed it's contents.
+That <code>struct hchan&lt;*testing.T&gt;</code> is the
+runtime-internal representation of a channel. It is currently empty,
+or gdb would have pretty-printed its contents.
 </p>
 
 <p>

doc/gccgo_install.html

@@ -52,6 +52,19 @@ user libraries.  The Go 1.4 runtime is not fully merged, but that
 should not be visible to Go programs.
 </p>
 
+<p>
+The GCC 6 releases include a complete implementation of the Go 1.6.1
+user libraries.  The Go 1.6 runtime is not fully merged, but that
+should not be visible to Go programs.
+</p>
+
+<p>
+The GCC 7 releases are expected to include a complete implementation
+of the Go 1.8 user libraries.  As with earlier releases, the Go 1.8
+runtime is not fully merged, but that should not be visible to Go
+programs.
+</p>
+
 <h2 id="Source_code">Source code</h2>
 
 <p>
@@ -160,23 +173,6 @@ make
 make install
 </pre>
 
-<h3 id="Ubuntu">A note on Ubuntu</h3>
-
-<p>
-Current versions of Ubuntu and versions of GCC before 4.8 disagree on
-where system libraries and header files are found.  This is not a
-gccgo issue.  When building older versions of GCC, setting these
-environment variables while configuring and building gccgo may fix the
-problem.
-</p>
-
-<pre>
-LIBRARY_PATH=/usr/lib/x86_64-linux-gnu
-C_INCLUDE_PATH=/usr/include/x86_64-linux-gnu
-CPLUS_INCLUDE_PATH=/usr/include/x86_64-linux-gnu
-export LIBRARY_PATH C_INCLUDE_PATH CPLUS_INCLUDE_PATH
-</pre>
-
 <h2 id="Using_gccgo">Using gccgo</h2>
 
 <p>
@@ -364,12 +360,15 @@ or with C++ code compiled using <code>extern "C"</code>.
 <h3 id="Types">Types</h3>
 
 <p>
-Basic types map directly: an <code>int</code> in Go is an <code>int</code>
-in C, an <code>int32</code> is an <code>int32_t</code>,
-etc.  Go <code>byte</code> is equivalent to C <code>unsigned
-char</code>.
-Pointers in Go are pointers in C. A Go <code>struct</code> is the same as C
-<code>struct</code> with the same fields and types.
+Basic types map directly: an <code>int32</code> in Go is
+an <code>int32_t</code> in C, an <code>int64</code> is
+an <code>int64_t</code>, etc.
+The Go type <code>int</code> is an integer that is the same size as a
+pointer, and as such corresponds to the C type <code>intptr_t</code>.
+Go <code>byte</code> is equivalent to C <code>unsigned char</code>.
+Pointers in Go are pointers in C.
+A Go <code>struct</code> is the same as C <code>struct</code> with the
+same fields and types.
 </p>
 
 <p>
@@ -380,7 +379,7 @@ structure (this is <b style="color: red;">subject to change</b>):
 <pre>
 struct __go_string {
   const unsigned char *__data;
-  int __length;
+  intptr_t __length;
 };
 </pre>
 
@@ -400,8 +399,8 @@ A slice in Go is a structure.  The current definition is
 <pre>
 struct __go_slice {
   void *__values;
-  int __count;
-  int __capacity;
+  intptr_t __count;
+  intptr_t __capacity;
 };
 </pre>
 
@@ -526,15 +525,3 @@ This procedure is full of unstated caveats and restrictions and we make no
 guarantee that it will not change in the future. It is more useful as a
 starting point for real Go code than as a regular procedure.
 </p>
-
-<h2 id="RTEMS_Port">RTEMS Port</h2>
-<p>
-The gccgo compiler has been ported to <a href="http://www.rtems.com/">
-<code>RTEMS</code></a>. <code>RTEMS</code> is a real-time executive
-that provides a high performance environment for embedded applications
-on a range of processors and embedded hardware. The current gccgo
-port is for x86. The goal is to extend the port to most of the
-<a href="http://www.rtems.org/wiki/index.php/SupportedCPUs">
-architectures supported by <code>RTEMS</code></a>. For more information on the port,
-as well as instructions on how to install it, please see this
-<a href="http://www.rtems.org/wiki/index.php/GCCGoRTEMS"><code>RTEMS</code> Wiki page</a>.

doc/go1.8.html

@@ -93,7 +93,8 @@ On OpenBSD, Go now requires OpenBSD 5.9 or later. <!-- CL 34093 -->
 <p>
 The Plan 9 port's networking support is now much more complete
 and matches the behavior of Unix and Windows with respect to deadlines
-and cancelation.
+and cancelation. For Plan 9 kernel requirements, see the
+<a href="https://golang.org/wiki/Plan9">Plan 9 wiki page</a>.
 </p>
 
 <p>
@@ -434,11 +435,11 @@ version of gccgo.
 <h3 id="plugin">Plugins</h3>
 
 <p>
-  Go now supports a “<code>plugin</code>” build mode for generating
-  plugins written in Go, and a
+  Go now provides early support for plugins with a “<code>plugin</code>”
+  build mode for generating plugins written in Go, and a
   new <a href="/pkg/plugin/"><code>plugin</code></a> package for
-  loading such plugins at run time. Plugin support is only currently
-  available on Linux.
+  loading such plugins at run time. Plugin support is currently only
+  available on Linux. Please report any issues.
 </p>
 
 <h2 id="runtime">Runtime</h2>
@@ -808,11 +809,6 @@ Optimizations and minor bug fixes are not listed.
 
 <dl id="crypto_x509"><dt><a href="/pkg/crypto/x509/">crypto/x509</a></dt>
   <dd>
-    <p> <!-- CL 30578 -->
-      <a href="/pkg/crypto/x509/#SystemCertPool"><code>SystemCertPool</code></a>
-      is now implemented on Windows.
-    </p>
-
     <p> <!-- CL 24743 -->
       PSS signatures are now supported.
     </p>
@@ -1617,9 +1613,9 @@ crypto/x509: return error for missing SerialNumber (CL 27238)
       June 31 and July 32.
     </p>
 
-    <p> <!-- CL 33029 -->
+    <p> <!-- CL 33029 --> <!-- CL 34816 -->
       The <code>tzdata</code> database has been updated to version
-      2016i for systems that don't already have a local time zone
+      2016j for systems that don't already have a local time zone
       database.
     </p>
 
@@ -1649,6 +1645,17 @@ crypto/x509: return error for missing SerialNumber (CL 27238)
       and only the overall execution of the test binary would fail.
     </p>
 
+    <p><!-- CL 32455 -->
+      The signature of the
+      <a href="/pkg/testing/#MainStart"><code>MainStart</code></a>
+      function has changed, as allowed by the documentation. It is an
+      internal detail and not part of the Go 1 compatibility promise.
+      If you're not calling <code>MainStart</code> directly but see
+      errors, that likely means you set the
+      normally-empty <code>GOROOT</code> environment variable and it
+      doesn't match the version of your <code>go</code> command's binary.
+    </p>
+
   </dd>
 </dl>
 

doc/install-source.html

@@ -147,6 +147,9 @@ either the git branch <code>release-branch.go1.4</code> or
 which contains the Go 1.4 source code plus accumulated fixes
 to keep the tools running on newer operating systems.
 (Go 1.4 was the last distribution in which the tool chain was written in C.)
+After unpacking the Go 1.4 source, <code>cd</code> to
+the <code>src</code> subdirectory and run <code>make.bash</code> (or,
+on Windows, <code>make.bat</code>).
 </p>
 
 <p>

doc/install.html

@@ -250,7 +250,7 @@ $ <b>cd $HOME/go/src/hello</b>
 $ <b>go build</b>
 </pre>
 
-<pre class="testWindows" style="display: none">
+<pre class="testWindows">
 C:\&gt; <b>cd %USERPROFILE%\go\src\hello</b>
 C:\Users\Gopher\go\src\hello&gt; <b>go build</b>
 </pre>
@@ -267,7 +267,7 @@ $ <b>./hello</b>
 hello, world
 </pre>
 
-<pre class="testWindows" style="display: none">
+<pre class="testWindows">
 C:\Users\Gopher\go\src\hello&gt; <b>hello</b>
 hello, world
 </pre>

misc/cgo/test/issue18146.go

@@ -73,7 +73,7 @@ func test18146(t *testing.T) {
 		}
 		runtime.GOMAXPROCS(threads)
 		argv := append(os.Args, "-test.run=NoSuchTestExists")
-		if err := syscall.Exec(os.Args[0], argv, nil); err != nil {
+		if err := syscall.Exec(os.Args[0], argv, os.Environ()); err != nil {
 			t.Fatal(err)
 		}
 	}

misc/cgo/test/sigaltstack.go

@@ -17,7 +17,7 @@ package cgotest
 static stack_t oss;
 static char signalStack[SIGSTKSZ];
 
-static void changeSignalStack() {
+static void changeSignalStack(void) {
 	stack_t ss;
 	memset(&ss, 0, sizeof ss);
 	ss.ss_sp = signalStack;
@@ -29,7 +29,7 @@ static void changeSignalStack() {
 	}
 }
 
-static void restoreSignalStack() {
+static void restoreSignalStack(void) {
 #if (defined(__x86_64__) || defined(__i386__)) && defined(__APPLE__)
 	// The Darwin C library enforces a minimum that the kernel does not.
 	// This is OK since we allocated this much space in mpreinit,
@@ -42,7 +42,7 @@ static void restoreSignalStack() {
 	}
 }
 
-static int zero() {
+static int zero(void) {
 	return 0;
 }
 */

misc/cgo/testplugin/src/iface/main.go

@@ -0,0 +1,46 @@
+// Copyright 2017 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 main
+
+import (
+	"iface_i"
+	"log"
+	"plugin"
+)
+
+func main() {
+	a, err := plugin.Open("iface_a.so")
+	if err != nil {
+		log.Fatalf(`plugin.Open("iface_a.so"): %v`, err)
+	}
+	b, err := plugin.Open("iface_b.so")
+	if err != nil {
+		log.Fatalf(`plugin.Open("iface_b.so"): %v`, err)
+	}
+
+	af, err := a.Lookup("F")
+	if err != nil {
+		log.Fatalf(`a.Lookup("F") failed: %v`, err)
+	}
+	bf, err := b.Lookup("F")
+	if err != nil {
+		log.Fatalf(`b.Lookup("F") failed: %v`, err)
+	}
+	if af.(func() interface{})() != bf.(func() interface{})() {
+		panic("empty interfaces not equal")
+	}
+
+	ag, err := a.Lookup("G")
+	if err != nil {
+		log.Fatalf(`a.Lookup("G") failed: %v`, err)
+	}
+	bg, err := b.Lookup("G")
+	if err != nil {
+		log.Fatalf(`b.Lookup("G") failed: %v`, err)
+	}
+	if ag.(func() iface_i.I)() != bg.(func() iface_i.I)() {
+		panic("nonempty interfaces not equal")
+	}
+}

misc/cgo/testplugin/src/iface_a/a.go

@@ -0,0 +1,17 @@
+// Copyright 2017 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 main
+
+import "iface_i"
+
+//go:noinline
+func F() interface{} {
+	return (*iface_i.T)(nil)
+}
+
+//go:noinline
+func G() iface_i.I {
+	return (*iface_i.T)(nil)
+}

misc/cgo/testplugin/src/iface_b/b.go

@@ -0,0 +1,17 @@
+// Copyright 2017 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 main
+
+import "iface_i"
+
+//go:noinline
+func F() interface{} {
+	return (*iface_i.T)(nil)
+}
+
+//go:noinline
+func G() iface_i.I {
+	return (*iface_i.T)(nil)
+}

misc/cgo/testplugin/src/iface_i/i.go

@@ -0,0 +1,17 @@
+// Copyright 2017 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 iface_i
+
+type I interface {
+	M()
+}
+
+type T struct {
+}
+
+func (t *T) M() {
+}
+
+// *T implements I

misc/cgo/testplugin/src/issue18676/dynamodbstreamsevt/definition.go

@@ -0,0 +1,13 @@
+// Copyright 2017 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 dynamodbstreamsevt
+
+import "encoding/json"
+
+var foo json.RawMessage
+
+type Event struct{}
+
+func (e *Event) Dummy() {}

misc/cgo/testplugin/src/issue18676/main.go

@@ -0,0 +1,31 @@
+// Copyright 2017 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.
+
+// The bug happened like this:
+// 1) The main binary adds an itab for *json.UnsupportedValueError / error
+//    (concrete type / interface type).  This itab goes in hash bucket 0x111.
+// 2) The plugin adds that same itab again.  That makes a cycle in the itab
+//    chain rooted at hash bucket 0x111.
+// 3) The main binary then asks for the itab for *dynamodbstreamsevt.Event /
+//    json.Unmarshaler.  This itab happens to also live in bucket 0x111.
+//    The lookup code goes into an infinite loop searching for this itab.
+// The code is carefully crafted so that the two itabs are both from the
+// same bucket, and so that the second itab doesn't exist in
+// the itab hashmap yet (so the entire linked list must be searched).
+package main
+
+import (
+	"encoding/json"
+	"issue18676/dynamodbstreamsevt"
+	"plugin"
+)
+
+func main() {
+	plugin.Open("plugin.so")
+
+	var x interface{} = (*dynamodbstreamsevt.Event)(nil)
+	if _, ok := x.(json.Unmarshaler); !ok {
+		println("something")
+	}
+}

misc/cgo/testplugin/src/issue18676/plugin.go

@@ -0,0 +1,11 @@
+// Copyright 2017 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 main
+
+import "C"
+
+import "issue18676/dynamodbstreamsevt"
+
+func F(evt *dynamodbstreamsevt.Event) {}

misc/cgo/testplugin/test.bash

@@ -15,8 +15,8 @@ goos=$(go env GOOS)
 goarch=$(go env GOARCH)
 
 function cleanup() {
-	rm -f plugin*.so unnamed*.so
-	rm -rf host pkg sub
+	rm -f plugin*.so unnamed*.so iface*.so
+	rm -rf host pkg sub iface issue18676
 }
 trap cleanup EXIT
 
@@ -32,3 +32,15 @@ GOPATH=$(pwd) go build -buildmode=plugin unnamed2.go
 GOPATH=$(pwd) go build host
 
 LD_LIBRARY_PATH=$(pwd) ./host
+
+# Test that types and itabs get properly uniqified.
+GOPATH=$(pwd) go build -buildmode=plugin iface_a
+GOPATH=$(pwd) go build -buildmode=plugin iface_b
+GOPATH=$(pwd) go build iface
+LD_LIBRARY_PATH=$(pwd) ./iface
+
+# Test for issue 18676 - make sure we don't add the same itab twice.
+# The buggy code hangs forever, so use a timeout to check for that.
+GOPATH=$(pwd) go build -buildmode=plugin -o plugin.so src/issue18676/plugin.go
+GOPATH=$(pwd) go build -o issue18676 src/issue18676/main.go
+timeout 10s ./issue18676

misc/cgo/testsanitizers/msan_shared.go

@@ -0,0 +1,12 @@
+// Copyright 2017 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.
+
+// This program segfaulted during libpreinit when built with -msan:
+// http://golang.org/issue/18707
+
+package main
+
+import "C"
+
+func main() {}

misc/cgo/testsanitizers/test.bash

@@ -68,6 +68,25 @@ fi
 
 status=0
 
+testmsanshared() {
+  goos=$(go env GOOS)
+  suffix="-installsuffix testsanitizers"
+  libext="so"
+  if [ "$goos" == "darwin" ]; then
+	  libext="dylib"
+  fi
+  go build -msan -buildmode=c-shared $suffix -o ${TMPDIR}/libmsanshared.$libext msan_shared.go
+
+	echo 'int main() { return 0; }' > ${TMPDIR}/testmsanshared.c
+  $CC $(go env GOGCCFLAGS) -fsanitize=memory -o ${TMPDIR}/testmsanshared ${TMPDIR}/testmsanshared.c ${TMPDIR}/libmsanshared.$libext
+
+  if ! LD_LIBRARY_PATH=. ${TMPDIR}/testmsanshared; then
+    echo "FAIL: msan_shared"
+    status=1
+  fi
+  rm -f ${TMPDIR}/{testmsanshared,testmsanshared.c,libmsanshared.$libext}
+}
+
 if test "$msan" = "yes"; then
     if ! go build -msan std; then
 	echo "FAIL: build -msan std"
@@ -108,6 +127,8 @@ if test "$msan" = "yes"; then
 	echo "FAIL: msan_fail"
 	status=1
     fi
+
+    testmsanshared
 fi
 
 if test "$tsan" = "yes"; then

misc/cgo/testshared/shared_test.go

@@ -815,3 +815,14 @@ func TestImplicitInclusion(t *testing.T) {
 	goCmd(t, "install", "-linkshared", "implicitcmd")
 	run(t, "running executable linked against library that contains same package as it", "./bin/implicitcmd")
 }
+
+// Tests to make sure that the type fields of empty interfaces and itab
+// fields of nonempty interfaces are unique even across modules,
+// so that interface equality works correctly.
+func TestInterface(t *testing.T) {
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "iface_a")
+	// Note: iface_i gets installed implicitly as a dependency of iface_a.
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "iface_b")
+	goCmd(t, "install", "-linkshared", "iface")
+	run(t, "running type/itab uniqueness tester", "./bin/iface")
+}

misc/cgo/testshared/src/depBase/dep.go

@@ -5,6 +5,8 @@ import (
 	"reflect"
 )
 
+var SlicePtr interface{} = &[]int{}
+
 var V int = 1
 
 var HasMask []string = []string{"hi"}

misc/cgo/testshared/src/exe/exe.go

@@ -19,6 +19,8 @@ func F() *C {
 	return nil
 }
 
+var slicePtr interface{} = &[]int{}
+
 func main() {
 	defer depBase.ImplementedInAsm()
 	// This code below causes various go.itab.* symbols to be generated in
@@ -32,4 +34,11 @@ func main() {
 	if reflect.TypeOf(F).Out(0) != reflect.TypeOf(c) {
 		panic("bad reflection results, see golang.org/issue/18252")
 	}
+
+	sp := reflect.New(reflect.TypeOf(slicePtr).Elem())
+	s := sp.Interface()
+
+	if reflect.TypeOf(s) != reflect.TypeOf(slicePtr) {
+		panic("bad reflection results, see golang.org/issue/18729")
+	}
 }

misc/cgo/testshared/src/iface/main.go

@@ -0,0 +1,17 @@
+// Copyright 2017 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 main
+
+import "iface_a"
+import "iface_b"
+
+func main() {
+	if iface_a.F() != iface_b.F() {
+		panic("empty interfaces not equal")
+	}
+	if iface_a.G() != iface_b.G() {
+		panic("non-empty interfaces not equal")
+	}
+}

misc/cgo/testshared/src/iface_a/a.go

@@ -0,0 +1,17 @@
+// Copyright 2017 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 iface_a
+
+import "iface_i"
+
+//go:noinline
+func F() interface{} {
+	return (*iface_i.T)(nil)
+}
+
+//go:noinline
+func G() iface_i.I {
+	return (*iface_i.T)(nil)
+}

misc/cgo/testshared/src/iface_b/b.go

@@ -0,0 +1,17 @@
+// Copyright 2017 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 iface_b
+
+import "iface_i"
+
+//go:noinline
+func F() interface{} {
+	return (*iface_i.T)(nil)
+}
+
+//go:noinline
+func G() iface_i.I {
+	return (*iface_i.T)(nil)
+}

misc/cgo/testshared/src/iface_i/i.go

@@ -0,0 +1,17 @@
+// Copyright 2017 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 iface_i
+
+type I interface {
+	M()
+}
+
+type T struct {
+}
+
+func (t *T) M() {
+}
+
+// *T implements I

misc/ios/go_darwin_arm_exec.go

@@ -99,7 +99,7 @@ func main() {
 	// Approximately 1 in a 100 binaries fail to start. If it happens,
 	// try again. These failures happen for several reasons beyond
 	// our control, but all of them are safe to retry as they happen
-	// before lldb encounters the initial getwd breakpoint. As we
+	// before lldb encounters the initial SIGUSR2 stop. As we
 	// know the tests haven't started, we are not hiding flaky tests
 	// with this retry.
 	for i := 0; i < 5; i++ {
@@ -204,6 +204,11 @@ func run(bin string, args []string) (err error) {
 	var opts options
 	opts, args = parseArgs(args)
 
+	// Pass the suffix for the current working directory as the
+	// first argument to the test. For iOS, cmd/go generates
+	// special handling of this argument.
+	args = append([]string{"cwdSuffix=" + pkgpath}, args...)
+
 	// ios-deploy invokes lldb to give us a shell session with the app.
 	s, err := newSession(appdir, args, opts)
 	if err != nil {
@@ -224,6 +229,7 @@ func run(bin string, args []string) (err error) {
 	s.do(`process handle SIGHUP  --stop false --pass true --notify false`)
 	s.do(`process handle SIGPIPE --stop false --pass true --notify false`)
 	s.do(`process handle SIGUSR1 --stop false --pass true --notify false`)
+	s.do(`process handle SIGUSR2 --stop true --pass false --notify true`) // sent by test harness
 	s.do(`process handle SIGCONT --stop false --pass true --notify false`)
 	s.do(`process handle SIGSEGV --stop false --pass true --notify false`) // does not work
 	s.do(`process handle SIGBUS  --stop false --pass true --notify false`) // does not work
@@ -236,20 +242,9 @@ func run(bin string, args []string) (err error) {
 		return nil
 	}
 
-	s.do(`breakpoint set -n getwd`) // in runtime/cgo/gcc_darwin_arm.go
-
 	started = true
 
-	s.doCmd("run", "stop reason = breakpoint", 20*time.Second)
-
-	// Move the current working directory into the faux gopath.
-	if pkgpath != "src" {
-		s.do(`breakpoint delete 1`)
-		s.do(`expr char* $mem = (char*)malloc(512)`)
-		s.do(`expr $mem = (char*)getwd($mem, 512)`)
-		s.do(`expr $mem = (char*)strcat($mem, "/` + pkgpath + `")`)
-		s.do(`call (void)chdir($mem)`)
-	}
+	s.doCmd("run", "stop reason = signal SIGUSR2", 20*time.Second)
 
 	startTestsLen := s.out.Len()
 	fmt.Fprintln(s.in, `process continue`)
@@ -520,13 +515,11 @@ func copyLocalData(dstbase string) (pkgpath string, err error) {
 
 	// Copy timezone file.
 	//
-	// Typical apps have the zoneinfo.zip in the root of their app bundle,
+	// Apps have the zoneinfo.zip in the root of their app bundle,
 	// read by the time package as the working directory at initialization.
-	// As we move the working directory to the GOROOT pkg directory, we
-	// install the zoneinfo.zip file in the pkgpath.
 	if underGoRoot {
 		err := cp(
-			filepath.Join(dstbase, pkgpath),
+			dstbase,
 			filepath.Join(cwd, "lib", "time", "zoneinfo.zip"),
 		)
 		if err != nil {

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

@@ -303,7 +303,9 @@ func genhash(sym *Sym, t *Type) {
 	typecheckslice(fn.Nbody.Slice(), Etop)
 	Curfn = nil
 	popdcl()
-	testdclstack()
+	if debug_dclstack != 0 {
+		testdclstack()
+	}
 
 	// Disable safemode while compiling this code: the code we
 	// generate internally can refer to unsafe.Pointer.
@@ -493,7 +495,9 @@ func geneq(sym *Sym, t *Type) {
 	typecheckslice(fn.Nbody.Slice(), Etop)
 	Curfn = nil
 	popdcl()
-	testdclstack()
+	if debug_dclstack != 0 {
+		testdclstack()
+	}
 
 	// Disable safemode while compiling this code: the code we
 	// generate internally can refer to unsafe.Pointer.

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

@@ -217,7 +217,9 @@ func Import(in *bufio.Reader) {
 	typecheckok = tcok
 	resumecheckwidth()
 
-	testdclstack() // debugging only
+	if debug_dclstack != 0 {
+		testdclstack()
+	}
 }
 
 func formatErrorf(format string, args ...interface{}) {

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

@@ -30,11 +30,12 @@ var (
 )
 
 var (
-	Debug_append  int
-	Debug_closure int
-	Debug_panic   int
-	Debug_slice   int
-	Debug_wb      int
+	Debug_append   int
+	Debug_closure  int
+	debug_dclstack int
+	Debug_panic    int
+	Debug_slice    int
+	Debug_wb       int
 )
 
 // Debug arguments.
@@ -48,6 +49,7 @@ var debugtab = []struct {
 	{"append", &Debug_append},         // print information about append compilation
 	{"closure", &Debug_closure},       // print information about closure compilation
 	{"disablenil", &disable_checknil}, // disable nil checks
+	{"dclstack", &debug_dclstack},     // run internal dclstack checks
 	{"gcprog", &Debug_gcprog},         // print dump of GC programs
 	{"nil", &Debug_checknil},          // print information about nil checks
 	{"panic", &Debug_panic},           // do not hide any compiler panic
@@ -325,7 +327,6 @@ func Main() {
 	timings.Stop()
 	timings.AddEvent(int64(lexlineno-lexlineno0), "lines")
 
-	testdclstack()
 	mkpackage(localpkg.Name) // final import not used checks
 	finishUniverse()
 

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

@@ -34,6 +34,7 @@ func parseFile(filename string) {
 	}
 
 	if nsyntaxerrors == 0 {
+		// Always run testdclstack here, even when debug_dclstack is not set, as a sanity measure.
 		testdclstack()
 	}
 }

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

@@ -1833,7 +1833,9 @@ func genwrapper(rcvr *Type, method *Field, newnam *Sym, iface int) {
 	funcbody(fn)
 	Curfn = fn
 	popdcl()
-	testdclstack()
+	if debug_dclstack != 0 {
+		testdclstack()
+	}
 
 	// wrappers where T is anonymous (struct or interface) can be duplicated.
 	if rcvr.IsStruct() || rcvr.IsInterface() || rcvr.IsPtr() && rcvr.Elem().IsStruct() {

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

@@ -57,8 +57,13 @@ func startProfile() {
 			Fatalf("%v", err)
 		}
 		atExit(func() {
-			runtime.GC() // profile all outstanding allocations
-			if err := pprof.WriteHeapProfile(f); err != nil {
+			// Profile all outstanding allocations.
+			runtime.GC()
+			// compilebench parses the memory profile to extract memstats,
+			// which are only written in the legacy pprof format.
+			// See golang.org/issue/18641 and runtime/pprof/pprof.go:writeHeap.
+			const writeLegacyFormat = 1
+			if err := pprof.Lookup("heap").WriteTo(f, writeLegacyFormat); err != nil {
 				Fatalf("%v", err)
 			}
 		})

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

@@ -3117,12 +3117,12 @@ func walkcompare(n *Node, init *Nodes) *Node {
 		cmpr = cmpr.Left
 	}
 
-	if !islvalue(cmpl) || !islvalue(cmpr) {
-		Fatalf("arguments of comparison must be lvalues - %v %v", cmpl, cmpr)
-	}
-
 	// Chose not to inline. Call equality function directly.
 	if !inline {
+		if !islvalue(cmpl) || !islvalue(cmpr) {
+			Fatalf("arguments of comparison must be lvalues - %v %v", cmpl, cmpr)
+		}
+
 		// eq algs take pointers
 		pl := temp(ptrto(t))
 		al := nod(OAS, pl, nod(OADDR, cmpl, nil))

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

@@ -885,9 +885,9 @@
 (MOVDEQ y _ (FlagLT)) -> y
 (MOVDEQ y _ (FlagGT)) -> y
 
-(MOVDNE _ y (FlagEQ)) -> y
-(MOVDNE x _ (FlagLT)) -> x
-(MOVDNE x _ (FlagGT)) -> x
+(MOVDNE y _ (FlagEQ)) -> y
+(MOVDNE _ x (FlagLT)) -> x
+(MOVDNE _ x (FlagGT)) -> x
 
 (MOVDLT y _ (FlagEQ)) -> y
 (MOVDLT _ x (FlagLT)) -> x

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

@@ -82,7 +82,7 @@ func nilcheckelim(f *Func) {
 				}
 			}
 
-			// Next, process values in the block.
+			// Next, eliminate any redundant nil checks in this block.
 			i := 0
 			for _, v := range b.Values {
 				b.Values[i] = v
@@ -105,13 +105,10 @@ func nilcheckelim(f *Func) {
 							f.Config.Warnl(v.Line, "removed nil check")
 						}
 						v.reset(OpUnknown)
+						// TODO: f.freeValue(v)
 						i--
 						continue
 					}
-					// Record the fact that we know ptr is non nil, and remember to
-					// undo that information when this dominator subtree is done.
-					nonNilValues[ptr.ID] = true
-					work = append(work, bp{op: ClearPtr, ptr: ptr})
 				}
 			}
 			for j := i; j < len(b.Values); j++ {
@@ -119,6 +116,21 @@ func nilcheckelim(f *Func) {
 			}
 			b.Values = b.Values[:i]
 
+			// Finally, find redundant nil checks for subsequent blocks.
+			// Note that we can't add these until the loop above is done, as the
+			// values in the block are not ordered in any way when this pass runs.
+			// This was the cause of issue #18725.
+			for _, v := range b.Values {
+				if v.Op != OpNilCheck {
+					continue
+				}
+				ptr := v.Args[0]
+				// Record the fact that we know ptr is non nil, and remember to
+				// undo that information when this dominator subtree is done.
+				nonNilValues[ptr.ID] = true
+				work = append(work, bp{op: ClearPtr, ptr: ptr})
+			}
+
 			// Add all dominated blocks to the work list.
 			for w := sdom[node.block.ID].child; w != nil; w = sdom[w.ID].sibling {
 				work = append(work, bp{op: Work, block: w})

src/cmd/compile/internal/ssa/rewriteS390X.go

@@ -9847,11 +9847,11 @@ func rewriteValueS390X_OpS390XMOVDNE(v *Value, config *Config) bool {
 		v.AddArg(cmp)
 		return true
 	}
-	// match: (MOVDNE _ y (FlagEQ))
+	// match: (MOVDNE y _ (FlagEQ))
 	// cond:
 	// result: y
 	for {
-		y := v.Args[1]
+		y := v.Args[0]
 		v_2 := v.Args[2]
 		if v_2.Op != OpS390XFlagEQ {
 			break
@@ -9861,11 +9861,11 @@ func rewriteValueS390X_OpS390XMOVDNE(v *Value, config *Config) bool {
 		v.AddArg(y)
 		return true
 	}
-	// match: (MOVDNE x _ (FlagLT))
+	// match: (MOVDNE _ x (FlagLT))
 	// cond:
 	// result: x
 	for {
-		x := v.Args[0]
+		x := v.Args[1]
 		v_2 := v.Args[2]
 		if v_2.Op != OpS390XFlagLT {
 			break
@@ -9875,11 +9875,11 @@ func rewriteValueS390X_OpS390XMOVDNE(v *Value, config *Config) bool {
 		v.AddArg(x)
 		return true
 	}
-	// match: (MOVDNE x _ (FlagGT))
+	// match: (MOVDNE _ x (FlagGT))
 	// cond:
 	// result: x
 	for {
-		x := v.Args[0]
+		x := v.Args[1]
 		v_2 := v.Args[2]
 		if v_2.Op != OpS390XFlagGT {
 			break

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

@@ -35,7 +35,7 @@ func writebarrier(f *Func) {
 	valueLoop:
 		for i, v := range b.Values {
 			switch v.Op {
-			case OpStoreWB, OpMoveWB, OpMoveWBVolatile:
+			case OpStoreWB, OpMoveWB, OpMoveWBVolatile, OpZeroWB:
 				if IsStackAddr(v.Args[0]) {
 					switch v.Op {
 					case OpStoreWB:

src/cmd/go/bug.go

@@ -20,11 +20,10 @@ import (
 var cmdBug = &Command{
 	Run:       runBug,
 	UsageLine: "bug",
-	Short:     "print information for bug reports",
+	Short:     "start a bug report",
 	Long: `
-Bug prints information that helps file effective bug reports.
-
-Bugs may be reported at https://golang.org/issue/new.
+Bug opens the default browser and starts a new bug report.
+The report includes useful system information.
 	`,
 }
 

src/cmd/go/go_test.go

@@ -3787,3 +3787,26 @@ GLOBL ·constants<>(SB),8,$8
 	tg.setenv("GOPATH", tg.path("go"))
 	tg.run("build", "p")
 }
+
+// Issue 18778.
+func TestDotDotDotOutsideGOPATH(t *testing.T) {
+	tg := testgo(t)
+	defer tg.cleanup()
+
+	tg.tempFile("pkgs/a.go", `package x`)
+	tg.tempFile("pkgs/a_test.go", `package x_test
+import "testing"
+func TestX(t *testing.T) {}`)
+
+	tg.tempFile("pkgs/a/a.go", `package a`)
+	tg.tempFile("pkgs/a/a_test.go", `package a_test
+import "testing"
+func TestA(t *testing.T) {}`)
+
+	tg.cd(tg.path("pkgs"))
+	tg.run("build", "./...")
+	tg.run("test", "./...")
+	tg.run("list", "./...")
+	tg.grepStdout("pkgs$", "expected package not listed")
+	tg.grepStdout("pkgs/a", "expected package not listed")
+}

src/cmd/go/pkg.go

@@ -429,7 +429,7 @@ func setErrorPos(p *Package, importPos []token.Position) *Package {
 func cleanImport(path string) string {
 	orig := path
 	path = pathpkg.Clean(path)
-	if strings.HasPrefix(orig, "./") && path != ".." && path != "." && !strings.HasPrefix(path, "../") {
+	if strings.HasPrefix(orig, "./") && path != ".." && !strings.HasPrefix(path, "../") {
 		path = "./" + path
 	}
 	return path

src/cmd/go/test.go

@@ -894,9 +894,13 @@ func (b *builder) test(p *Package) (buildAction, runAction, printAction *action,
 
 	if buildContext.GOOS == "darwin" {
 		if buildContext.GOARCH == "arm" || buildContext.GOARCH == "arm64" {
-			t.NeedCgo = true
+			t.IsIOS = true
+			t.NeedOS = true
 		}
 	}
+	if t.TestMain == nil {
+		t.NeedOS = true
+	}
 
 	for _, cp := range pmain.imports {
 		if len(cp.coverVars) > 0 {
@@ -1343,7 +1347,8 @@ type testFuncs struct {
 	NeedTest    bool
 	ImportXtest bool
 	NeedXtest   bool
-	NeedCgo     bool
+	NeedOS      bool
+	IsIOS       bool
 	Cover       []coverInfo
 }
 
@@ -1444,7 +1449,7 @@ var testmainTmpl = template.Must(template.New("main").Parse(`
 package main
 
 import (
-{{if not .TestMain}}
+{{if .NeedOS}}
 	"os"
 {{end}}
 	"testing"
@@ -1460,8 +1465,10 @@ import (
 	_cover{{$i}} {{$p.Package.ImportPath | printf "%q"}}
 {{end}}
 
-{{if .NeedCgo}}
+{{if .IsIOS}}
+	"os/signal"
 	_ "runtime/cgo"
+	"syscall"
 {{end}}
 )
 
@@ -1523,6 +1530,32 @@ func coverRegisterFile(fileName string, counter []uint32, pos []uint32, numStmts
 {{end}}
 
 func main() {
+{{if .IsIOS}}
+	// Send a SIGUSR2, which will be intercepted by LLDB to
+	// tell the test harness that installation was successful.
+	// See misc/ios/go_darwin_arm_exec.go.
+	signal.Notify(make(chan os.Signal), syscall.SIGUSR2)
+	syscall.Kill(0, syscall.SIGUSR2)
+	signal.Reset(syscall.SIGUSR2)
+
+	// The first argument supplied to an iOS test is an offset
+	// suffix for the current working directory.
+	// Process it here, and remove it from os.Args.
+	const hdr = "cwdSuffix="
+	if len(os.Args) < 2 || len(os.Args[1]) <= len(hdr) || os.Args[1][:len(hdr)] != hdr {
+		panic("iOS test not passed a working directory suffix")
+	}
+	suffix := os.Args[1][len(hdr):]
+	dir, err := os.Getwd()
+	if err != nil {
+		panic(err)
+	}
+	if err := os.Chdir(dir + "/" + suffix); err != nil {
+		panic(err)
+	}
+	os.Args = append([]string{os.Args[0]}, os.Args[2:]...)
+{{end}}
+
 {{if .CoverEnabled}}
 	testing.RegisterCover(testing.Cover{
 		Mode: {{printf "%q" .CoverMode}},

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

@@ -1080,7 +1080,7 @@ func writelines(ctxt *Link, syms []*Symbol) ([]*Symbol, []*Symbol) {
 		epcs = s
 
 		dsym := ctxt.Syms.Lookup(dwarf.InfoPrefix+s.Name, int(s.Version))
-		dsym.Attr |= AttrHidden
+		dsym.Attr |= AttrHidden | AttrReachable
 		dsym.Type = obj.SDWARFINFO
 		for _, r := range dsym.R {
 			if r.Type == obj.R_DWARFREF && r.Sym.Size == 0 {

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

@@ -168,7 +168,7 @@ func container(s *Symbol) int {
 	if s == nil {
 		return 0
 	}
-	if Buildmode == BuildmodePlugin && onlycsymbol(s) {
+	if Buildmode == BuildmodePlugin && Headtype == obj.Hdarwin && onlycsymbol(s) {
 		return 1
 	}
 	// We want to generate func table entries only for the "lowest level" symbols,

src/compress/bzip2/bzip2_test.go

@@ -204,12 +204,6 @@ func TestMTF(t *testing.T) {
 	}
 }
 
-var (
-	digits = mustLoadFile("testdata/e.txt.bz2")
-	twain  = mustLoadFile("testdata/Mark.Twain-Tom.Sawyer.txt.bz2")
-	random = mustLoadFile("testdata/random.data.bz2")
-)
-
 func benchmarkDecode(b *testing.B, compressed []byte) {
 	// Determine the uncompressed size of testfile.
 	uncompressedSize, err := io.Copy(ioutil.Discard, NewReader(bytes.NewReader(compressed)))
@@ -227,6 +221,18 @@ func benchmarkDecode(b *testing.B, compressed []byte) {
 	}
 }
 
-func BenchmarkDecodeDigits(b *testing.B) { benchmarkDecode(b, digits) }
-func BenchmarkDecodeTwain(b *testing.B)  { benchmarkDecode(b, twain) }
-func BenchmarkDecodeRand(b *testing.B)   { benchmarkDecode(b, random) }
+func BenchmarkDecodeDigits(b *testing.B) {
+	digits := mustLoadFile("testdata/e.txt.bz2")
+	b.ResetTimer()
+	benchmarkDecode(b, digits)
+}
+func BenchmarkDecodeTwain(b *testing.B) {
+	twain := mustLoadFile("testdata/Mark.Twain-Tom.Sawyer.txt.bz2")
+	b.ResetTimer()
+	benchmarkDecode(b, twain)
+}
+func BenchmarkDecodeRand(b *testing.B) {
+	random := mustLoadFile("testdata/random.data.bz2")
+	b.ResetTimer()
+	benchmarkDecode(b, random)
+}

src/compress/flate/deflate.go

@@ -136,14 +136,17 @@ func (d *compressor) fillDeflate(b []byte) int {
 			delta := d.hashOffset - 1
 			d.hashOffset -= delta
 			d.chainHead -= delta
-			for i, v := range d.hashPrev {
+
+			// Iterate over slices instead of arrays to avoid copying
+			// the entire table onto the stack (Issue #18625).
+			for i, v := range d.hashPrev[:] {
 				if int(v) > delta {
 					d.hashPrev[i] = uint32(int(v) - delta)
 				} else {
 					d.hashPrev[i] = 0
 				}
 			}
-			for i, v := range d.hashHead {
+			for i, v := range d.hashHead[:] {
 				if int(v) > delta {
 					d.hashHead[i] = uint32(int(v) - delta)
 				} else {

src/compress/flate/deflate_test.go

@@ -12,6 +12,7 @@ import (
 	"io"
 	"io/ioutil"
 	"reflect"
+	"runtime/debug"
 	"sync"
 	"testing"
 )
@@ -864,3 +865,33 @@ func TestBestSpeedMaxMatchOffset(t *testing.T) {
 		}
 	}
 }
+
+func TestMaxStackSize(t *testing.T) {
+	// This test must not run in parallel with other tests as debug.SetMaxStack
+	// affects all goroutines.
+	n := debug.SetMaxStack(1 << 16)
+	defer debug.SetMaxStack(n)
+
+	var wg sync.WaitGroup
+	defer wg.Wait()
+
+	b := make([]byte, 1<<20)
+	for level := HuffmanOnly; level <= BestCompression; level++ {
+		// Run in separate goroutine to increase probability of stack regrowth.
+		wg.Add(1)
+		go func(level int) {
+			defer wg.Done()
+			zw, err := NewWriter(ioutil.Discard, level)
+			if err != nil {
+				t.Errorf("level %d, NewWriter() = %v, want nil", level, err)
+			}
+			if n, err := zw.Write(b); n != len(b) || err != nil {
+				t.Errorf("level %d, Write() = (%d, %v), want (%d, nil)", level, n, err, len(b))
+			}
+			if err := zw.Close(); err != nil {
+				t.Errorf("level %d, Close() = %v, want nil", level, err)
+			}
+			zw.Reset(ioutil.Discard)
+		}(level)
+	}
+}

src/compress/flate/deflatefast.go

@@ -60,7 +60,7 @@ func newDeflateFast() *deflateFast {
 func (e *deflateFast) encode(dst []token, src []byte) []token {
 	// Ensure that e.cur doesn't wrap.
 	if e.cur > 1<<30 {
-		*e = deflateFast{cur: maxStoreBlockSize, prev: e.prev[:0]}
+		e.resetAll()
 	}
 
 	// This check isn't in the Snappy implementation, but there, the caller
@@ -265,6 +265,21 @@ func (e *deflateFast) reset() {
 
 	// Protect against e.cur wraparound.
 	if e.cur > 1<<30 {
-		*e = deflateFast{cur: maxStoreBlockSize, prev: e.prev[:0]}
+		e.resetAll()
+	}
+}
+
+// resetAll resets the deflateFast struct and is only called in rare
+// situations to prevent integer overflow. It manually resets each field
+// to avoid causing large stack growth.
+//
+// See https://golang.org/issue/18636.
+func (e *deflateFast) resetAll() {
+	// This is equivalent to:
+	//	*e = deflateFast{cur: maxStoreBlockSize, prev: e.prev[:0]}
+	e.cur = maxStoreBlockSize
+	e.prev = e.prev[:0]
+	for i := range e.table {
+		e.table[i] = tableEntry{}
 	}
 }

src/compress/gzip/issue14937_test.go

@@ -9,11 +9,17 @@ import (
 	"testing"
 )
 
-// Per golang.org/issue/14937, check that every .gz file
-// in the tree has a zero mtime.
+// TestGZIPFilesHaveZeroMTimes checks that every .gz file in the tree
+// has a zero MTIME. This is a requirement for the Debian maintainers
+// to be able to have deterministic packages.
+//
+// See https://golang.org/issue/14937.
 func TestGZIPFilesHaveZeroMTimes(t *testing.T) {
-	if testing.Short() && testenv.Builder() == "" {
-		t.Skip("skipping in short mode")
+	// To avoid spurious false positives due to untracked GZIP files that
+	// may be in the user's GOROOT (Issue 18604), we only run this test on
+	// the builders, which should have a clean checkout of the tree.
+	if testenv.Builder() == "" {
+		t.Skip("skipping test on non-builder")
 	}
 	goroot, err := filepath.EvalSymlinks(runtime.GOROOT())
 	if err != nil {

src/crypto/dsa/dsa_test.go

@@ -95,7 +95,7 @@ func TestSignAndVerify(t *testing.T) {
 func TestSigningWithDegenerateKeys(t *testing.T) {
 	// Signing with degenerate private keys should not cause an infinite
 	// loop.
-	badKeys := []struct{
+	badKeys := []struct {
 		p, q, g, y, x string
 	}{
 		{"00", "01", "00", "00", "00"},
@@ -105,7 +105,7 @@ func TestSigningWithDegenerateKeys(t *testing.T) {
 	for i, test := range badKeys {
 		priv := PrivateKey{
 			PublicKey: PublicKey{
-				Parameters: Parameters {
+				Parameters: Parameters{
 					P: fromHex(test.p),
 					Q: fromHex(test.q),
 					G: fromHex(test.g),

src/crypto/tls/cipher_suites.go

@@ -84,15 +84,15 @@ var cipherSuites = []*cipherSuite{
 	{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, 16, 0, 4, ecdheECDSAKA, suiteECDHE | suiteECDSA | suiteTLS12, nil, nil, aeadAESGCM},
 	{TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, ecdheRSAKA, suiteECDHE | suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
 	{TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, ecdheECDSAKA, suiteECDHE | suiteECDSA | suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
-	{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, ecdheRSAKA, suiteECDHE | suiteTLS12, cipherAES, macSHA256, nil},
+	{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, ecdheRSAKA, suiteECDHE | suiteTLS12 | suiteDefaultOff, cipherAES, macSHA256, nil},
 	{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, 16, 20, 16, ecdheRSAKA, suiteECDHE, cipherAES, macSHA1, nil},
-	{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, ecdheECDSAKA, suiteECDHE | suiteECDSA | suiteTLS12, cipherAES, macSHA256, nil},
+	{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, ecdheECDSAKA, suiteECDHE | suiteECDSA | suiteTLS12 | suiteDefaultOff, cipherAES, macSHA256, nil},
 	{TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, 16, 20, 16, ecdheECDSAKA, suiteECDHE | suiteECDSA, cipherAES, macSHA1, nil},
 	{TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA, 32, 20, 16, ecdheRSAKA, suiteECDHE, cipherAES, macSHA1, nil},
 	{TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, 32, 20, 16, ecdheECDSAKA, suiteECDHE | suiteECDSA, cipherAES, macSHA1, nil},
 	{TLS_RSA_WITH_AES_128_GCM_SHA256, 16, 0, 4, rsaKA, suiteTLS12, nil, nil, aeadAESGCM},
 	{TLS_RSA_WITH_AES_256_GCM_SHA384, 32, 0, 4, rsaKA, suiteTLS12 | suiteSHA384, nil, nil, aeadAESGCM},
-	{TLS_RSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, rsaKA, suiteTLS12, cipherAES, macSHA256, nil},
+	{TLS_RSA_WITH_AES_128_CBC_SHA256, 16, 32, 16, rsaKA, suiteTLS12 | suiteDefaultOff, cipherAES, macSHA256, nil},
 	{TLS_RSA_WITH_AES_128_CBC_SHA, 16, 20, 16, rsaKA, 0, cipherAES, macSHA1, nil},
 	{TLS_RSA_WITH_AES_256_CBC_SHA, 32, 20, 16, rsaKA, 0, cipherAES, macSHA1, nil},
 	{TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA, 24, 20, 8, ecdheRSAKA, suiteECDHE, cipher3DES, macSHA1, nil},

src/crypto/tls/tls.go

@@ -6,8 +6,8 @@
 package tls
 
 // BUG(agl): The crypto/tls package only implements some countermeasures
-// against Lucky13 attacks on CBC-mode encryption. See
-// http://www.isg.rhul.ac.uk/tls/TLStiming.pdf and
+// against Lucky13 attacks on CBC-mode encryption, and only on SHA1
+// variants. See http://www.isg.rhul.ac.uk/tls/TLStiming.pdf and
 // https://www.imperialviolet.org/2013/02/04/luckythirteen.html.
 
 import (

src/crypto/x509/cert_pool.go

@@ -4,7 +4,11 @@
 
 package x509
 
-import "encoding/pem"
+import (
+	"encoding/pem"
+	"errors"
+	"runtime"
+)
 
 // CertPool is a set of certificates.
 type CertPool struct {
@@ -26,6 +30,11 @@ func NewCertPool() *CertPool {
 // Any mutations to the returned pool are not written to disk and do
 // not affect any other pool.
 func SystemCertPool() (*CertPool, error) {
+	if runtime.GOOS == "windows" {
+		// Issue 16736, 18609:
+		return nil, errors.New("crypto/x509: system root pool is not available on Windows")
+	}
+
 	return loadSystemRoots()
 }
 

src/crypto/x509/root_windows.go

@@ -226,6 +226,11 @@ func (c *Certificate) systemVerify(opts *VerifyOptions) (chains [][]*Certificate
 }
 
 func loadSystemRoots() (*CertPool, error) {
+	// TODO: restore this functionality on Windows. We tried to do
+	// it in Go 1.8 but had to revert it. See Issue 18609.
+	// Returning (nil, nil) was the old behavior, prior to CL 30578.
+	return nil, nil
+
 	const CRYPT_E_NOT_FOUND = 0x80092004
 
 	store, err := syscall.CertOpenSystemStore(0, syscall.StringToUTF16Ptr("ROOT"))

src/crypto/x509/x509_test.go

@@ -24,6 +24,7 @@ import (
 	"net"
 	"os/exec"
 	"reflect"
+	"runtime"
 	"strings"
 	"testing"
 	"time"
@@ -1477,6 +1478,9 @@ func TestMultipleRDN(t *testing.T) {
 }
 
 func TestSystemCertPool(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("not implemented on Windows; Issue 16736, 18609")
+	}
 	_, err := SystemCertPool()
 	if err != nil {
 		t.Fatal(err)

src/database/sql/sql.go

@@ -1357,16 +1357,7 @@ func (db *DB) begin(ctx context.Context, opts *TxOptions, strategy connReuseStra
 		cancel: cancel,
 		ctx:    ctx,
 	}
-	go func(tx *Tx) {
-		select {
-		case <-tx.ctx.Done():
-			if !tx.isDone() {
-				// Discard and close the connection used to ensure the transaction
-				// is closed and the resources are released.
-				tx.rollback(true)
-			}
-		}
-	}(tx)
+	go tx.awaitDone()
 	return tx, nil
 }
 
@@ -1388,6 +1379,11 @@ func (db *DB) Driver() driver.Driver {
 type Tx struct {
 	db *DB
 
+	// closemu prevents the transaction from closing while there
+	// is an active query. It is held for read during queries
+	// and exclusively during close.
+	closemu sync.RWMutex
+
 	// dc is owned exclusively until Commit or Rollback, at which point
 	// it's returned with putConn.
 	dc  *driverConn
@@ -1413,6 +1409,20 @@ type Tx struct {
 	ctx context.Context
 }
 
+// awaitDone blocks until the context in Tx is canceled and rolls back
+// the transaction if it's not already done.
+func (tx *Tx) awaitDone() {
+	// Wait for either the transaction to be committed or rolled
+	// back, or for the associated context to be closed.
+	<-tx.ctx.Done()
+
+	// Discard and close the connection used to ensure the
+	// transaction is closed and the resources are released.  This
+	// rollback does nothing if the transaction has already been
+	// committed or rolled back.
+	tx.rollback(true)
+}
+
 func (tx *Tx) isDone() bool {
 	return atomic.LoadInt32(&tx.done) != 0
 }
@@ -1424,16 +1434,31 @@ var ErrTxDone = errors.New("sql: Transaction has already been committed or rolle
 // close returns the connection to the pool and
 // must only be called by Tx.rollback or Tx.Commit.
 func (tx *Tx) close(err error) {
+	tx.closemu.Lock()
+	defer tx.closemu.Unlock()
+
 	tx.db.putConn(tx.dc, err)
 	tx.cancel()
 	tx.dc = nil
 	tx.txi = nil
 }
 
+// hookTxGrabConn specifies an optional hook to be called on
+// a successful call to (*Tx).grabConn. For tests.
+var hookTxGrabConn func()
+
 func (tx *Tx) grabConn(ctx context.Context) (*driverConn, error) {
+	select {
+	default:
+	case <-ctx.Done():
+		return nil, ctx.Err()
+	}
 	if tx.isDone() {
 		return nil, ErrTxDone
 	}
+	if hookTxGrabConn != nil { // test hook
+		hookTxGrabConn()
+	}
 	return tx.dc, nil
 }
 
@@ -1503,6 +1528,9 @@ func (tx *Tx) Rollback() error {
 // for the execution of the returned statement. The returned statement
 // will run in the transaction context.
 func (tx *Tx) PrepareContext(ctx context.Context, query string) (*Stmt, error) {
+	tx.closemu.RLock()
+	defer tx.closemu.RUnlock()
+
 	// TODO(bradfitz): We could be more efficient here and either
 	// provide a method to take an existing Stmt (created on
 	// perhaps a different Conn), and re-create it on this Conn if
@@ -1567,6 +1595,9 @@ func (tx *Tx) Prepare(query string) (*Stmt, error) {
 // The returned statement operates within the transaction and will be closed
 // when the transaction has been committed or rolled back.
 func (tx *Tx) StmtContext(ctx context.Context, stmt *Stmt) *Stmt {
+	tx.closemu.RLock()
+	defer tx.closemu.RUnlock()
+
 	// TODO(bradfitz): optimize this. Currently this re-prepares
 	// each time. This is fine for now to illustrate the API but
 	// we should really cache already-prepared statements
@@ -1618,6 +1649,9 @@ func (tx *Tx) Stmt(stmt *Stmt) *Stmt {
 // ExecContext executes a query that doesn't return rows.
 // For example: an INSERT and UPDATE.
 func (tx *Tx) ExecContext(ctx context.Context, query string, args ...interface{}) (Result, error) {
+	tx.closemu.RLock()
+	defer tx.closemu.RUnlock()
+
 	dc, err := tx.grabConn(ctx)
 	if err != nil {
 		return nil, err
@@ -1661,6 +1695,9 @@ func (tx *Tx) Exec(query string, args ...interface{}) (Result, error) {
 
 // QueryContext executes a query that returns rows, typically a SELECT.
 func (tx *Tx) QueryContext(ctx context.Context, query string, args ...interface{}) (*Rows, error) {
+	tx.closemu.RLock()
+	defer tx.closemu.RUnlock()
+
 	dc, err := tx.grabConn(ctx)
 	if err != nil {
 		return nil, err
@@ -2038,25 +2075,21 @@ type Rows struct {
 	// closed value is 1 when the Rows is closed.
 	// Use atomic operations on value when checking value.
 	closed    int32
-	ctxClose  chan struct{} // closed when Rows is closed, may be null.
+	cancel    func() // called when Rows is closed, may be nil.
 	lastcols  []driver.Value
 	lasterr   error       // non-nil only if closed is true
 	closeStmt *driverStmt // if non-nil, statement to Close on close
 }
 
 func (rs *Rows) initContextClose(ctx context.Context) {
-	if ctx.Done() == context.Background().Done() {
-		return
-	}
+	ctx, rs.cancel = context.WithCancel(ctx)
+	go rs.awaitDone(ctx)
+}
 
-	rs.ctxClose = make(chan struct{})
-	go func() {
-		select {
-		case <-ctx.Done():
-			rs.Close()
-		case <-rs.ctxClose:
-		}
-	}()
+// awaitDone blocks until the rows are closed or the context canceled.
+func (rs *Rows) awaitDone(ctx context.Context) {
+	<-ctx.Done()
+	rs.Close()
 }
 
 // Next prepares the next result row for reading with the Scan method. It
@@ -2314,7 +2347,9 @@ func (rs *Rows) Scan(dest ...interface{}) error {
 	return nil
 }
 
-var rowsCloseHook func(*Rows, *error)
+// rowsCloseHook returns a function so tests may install the
+// hook throug a test only mutex.
+var rowsCloseHook = func() func(*Rows, *error) { return nil }
 
 func (rs *Rows) isClosed() bool {
 	return atomic.LoadInt32(&rs.closed) != 0
@@ -2328,13 +2363,15 @@ func (rs *Rows) Close() error {
 	if !atomic.CompareAndSwapInt32(&rs.closed, 0, 1) {
 		return nil
 	}
-	if rs.ctxClose != nil {
-		close(rs.ctxClose)
-	}
+
 	err := rs.rowsi.Close()
-	if fn := rowsCloseHook; fn != nil {
+	if fn := rowsCloseHook(); fn != nil {
 		fn(rs, &err)
 	}
+	if rs.cancel != nil {
+		rs.cancel()
+	}
+
 	if rs.closeStmt != nil {
 		rs.closeStmt.Close()
 	}

src/database/sql/sql_test.go

@@ -14,6 +14,7 @@ import (
 	"runtime"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 )
@@ -326,9 +327,7 @@ func TestQueryContext(t *testing.T) {
 
 	// And verify that the final rows.Next() call, which hit EOF,
 	// also closed the rows connection.
-	if n := db.numFreeConns(); n != 1 {
-		t.Fatalf("free conns after query hitting EOF = %d; want 1", n)
-	}
+	waitForFree(t, db, 5*time.Second, 1)
 	if prepares := numPrepares(t, db) - prepares0; prepares != 1 {
 		t.Errorf("executed %d Prepare statements; want 1", prepares)
 	}
@@ -345,6 +344,18 @@ func waitCondition(waitFor, checkEvery time.Duration, fn func() bool) bool {
 	return false
 }
 
+// waitForFree checks db.numFreeConns until either it equals want or
+// the maxWait time elapses.
+func waitForFree(t *testing.T, db *DB, maxWait time.Duration, want int) {
+	var numFree int
+	if !waitCondition(maxWait, 5*time.Millisecond, func() bool {
+		numFree = db.numFreeConns()
+		return numFree == want
+	}) {
+		t.Fatalf("free conns after hitting EOF = %d; want %d", numFree, want)
+	}
+}
+
 func TestQueryContextWait(t *testing.T) {
 	db := newTestDB(t, "people")
 	defer closeDB(t, db)
@@ -361,9 +372,7 @@ func TestQueryContextWait(t *testing.T) {
 	}
 
 	// Verify closed rows connection after error condition.
-	if n := db.numFreeConns(); n != 1 {
-		t.Fatalf("free conns after query hitting EOF = %d; want 1", n)
-	}
+	waitForFree(t, db, 5*time.Second, 1)
 	if prepares := numPrepares(t, db) - prepares0; prepares != 1 {
 		t.Errorf("executed %d Prepare statements; want 1", prepares)
 	}
@@ -388,13 +397,7 @@ func TestTxContextWait(t *testing.T) {
 		t.Fatalf("expected QueryContext to error with context deadline exceeded but returned %v", err)
 	}
 
-	var numFree int
-	if !waitCondition(5*time.Second, 5*time.Millisecond, func() bool {
-		numFree = db.numFreeConns()
-		return numFree == 0
-	}) {
-		t.Fatalf("free conns after hitting EOF = %d; want 0", numFree)
-	}
+	waitForFree(t, db, 5*time.Second, 0)
 
 	// Ensure the dropped connection allows more connections to be made.
 	// Checked on DB Close.
@@ -471,9 +474,7 @@ func TestMultiResultSetQuery(t *testing.T) {
 
 	// And verify that the final rows.Next() call, which hit EOF,
 	// also closed the rows connection.
-	if n := db.numFreeConns(); n != 1 {
-		t.Fatalf("free conns after query hitting EOF = %d; want 1", n)
-	}
+	waitForFree(t, db, 5*time.Second, 1)
 	if prepares := numPrepares(t, db) - prepares0; prepares != 1 {
 		t.Errorf("executed %d Prepare statements; want 1", prepares)
 	}
@@ -1135,6 +1136,24 @@ func TestQueryRowClosingStmt(t *testing.T) {
 	}
 }
 
+var atomicRowsCloseHook atomic.Value // of func(*Rows, *error)
+
+func init() {
+	rowsCloseHook = func() func(*Rows, *error) {
+		fn, _ := atomicRowsCloseHook.Load().(func(*Rows, *error))
+		return fn
+	}
+}
+
+func setRowsCloseHook(fn func(*Rows, *error)) {
+	if fn == nil {
+		// Can't change an atomic.Value back to nil, so set it to this
+		// no-op func instead.
+		fn = func(*Rows, *error) {}
+	}
+	atomicRowsCloseHook.Store(fn)
+}
+
 // Test issue 6651
 func TestIssue6651(t *testing.T) {
 	db := newTestDB(t, "people")
@@ -1147,6 +1166,7 @@ func TestIssue6651(t *testing.T) {
 		return fmt.Errorf(want)
 	}
 	defer func() { rowsCursorNextHook = nil }()
+
 	err := db.QueryRow("SELECT|people|name|").Scan(&v)
 	if err == nil || err.Error() != want {
 		t.Errorf("error = %q; want %q", err, want)
@@ -1154,10 +1174,10 @@ func TestIssue6651(t *testing.T) {
 	rowsCursorNextHook = nil
 
 	want = "error in rows.Close"
-	rowsCloseHook = func(rows *Rows, err *error) {
+	setRowsCloseHook(func(rows *Rows, err *error) {
 		*err = fmt.Errorf(want)
-	}
-	defer func() { rowsCloseHook = nil }()
+	})
+	defer setRowsCloseHook(nil)
 	err = db.QueryRow("SELECT|people|name|").Scan(&v)
 	if err == nil || err.Error() != want {
 		t.Errorf("error = %q; want %q", err, want)
@@ -1830,7 +1850,9 @@ func TestStmtCloseDeps(t *testing.T) {
 		db.dumpDeps(t)
 	}
 
-	if len(stmt.css) > nquery {
+	if !waitCondition(5*time.Second, 5*time.Millisecond, func() bool {
+		return len(stmt.css) <= nquery
+	}) {
 		t.Errorf("len(stmt.css) = %d; want <= %d", len(stmt.css), nquery)
 	}
 
@@ -2576,10 +2598,10 @@ func TestIssue6081(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	rowsCloseHook = func(rows *Rows, err *error) {
+	setRowsCloseHook(func(rows *Rows, err *error) {
 		*err = driver.ErrBadConn
-	}
-	defer func() { rowsCloseHook = nil }()
+	})
+	defer setRowsCloseHook(nil)
 	for i := 0; i < 10; i++ {
 		rows, err := stmt.Query()
 		if err != nil {
@@ -2642,7 +2664,10 @@ func TestIssue18429(t *testing.T) {
 			if err != nil {
 				return
 			}
-			rows, err := tx.QueryContext(ctx, "WAIT|"+qwait+"|SELECT|people|name|")
+			// This is expected to give a cancel error many, but not all the time.
+			// Test failure will happen with a panic or other race condition being
+			// reported.
+			rows, _ := tx.QueryContext(ctx, "WAIT|"+qwait+"|SELECT|people|name|")
 			if rows != nil {
 				rows.Close()
 			}
@@ -2655,6 +2680,56 @@ func TestIssue18429(t *testing.T) {
 	time.Sleep(milliWait * 3 * time.Millisecond)
 }
 
+// TestIssue18719 closes the context right before use. The sql.driverConn
+// will nil out the ci on close in a lock, but if another process uses it right after
+// it will panic with on the nil ref.
+//
+// See https://golang.org/cl/35550 .
+func TestIssue18719(t *testing.T) {
+	db := newTestDB(t, "people")
+	defer closeDB(t, db)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	tx, err := db.BeginTx(ctx, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	hookTxGrabConn = func() {
+		cancel()
+
+		// Wait for the context to cancel and tx to rollback.
+		for tx.isDone() == false {
+			time.Sleep(time.Millisecond * 3)
+		}
+	}
+	defer func() { hookTxGrabConn = nil }()
+
+	// This call will grab the connection and cancel the context
+	// after it has done so. Code after must deal with the canceled state.
+	rows, err := tx.QueryContext(ctx, "SELECT|people|name|")
+	if err != nil {
+		rows.Close()
+		t.Fatalf("expected error %v but got %v", nil, err)
+	}
+
+	// Rows may be ignored because it will be closed when the context is canceled.
+
+	// Do not explicitly rollback. The rollback will happen from the
+	// canceled context.
+
+	// Wait for connections to return to pool.
+	var numOpen int
+	if !waitCondition(5*time.Second, 5*time.Millisecond, func() bool {
+		numOpen = db.numOpenConns()
+		return numOpen == 0
+	}) {
+		t.Fatalf("open conns after hitting EOF = %d; want 0", numOpen)
+	}
+}
+
 func TestConcurrency(t *testing.T) {
 	doConcurrentTest(t, new(concurrentDBQueryTest))
 	doConcurrentTest(t, new(concurrentDBExecTest))

src/go/ast/scope.go

@@ -70,10 +70,8 @@ func (s *Scope) String() string {
 // The Data fields contains object-specific data:
 //
 //	Kind    Data type         Data value
-//	Pkg	*types.Package    package scope
+//	Pkg     *Scope            package scope
 //	Con     int               iota for the respective declaration
-//	Con     != nil            constant value
-//	Typ     *Scope            (used as method scope during type checking - transient)
 //
 type Object struct {
 	Kind ObjKind

src/go/doc/doc_test.go

@@ -25,7 +25,7 @@ var files = flag.String("files", "", "consider only Go test files matching this
 
 const dataDir = "testdata"
 
-var templateTxt = readTemplate("template.txt")
+var templateTxt *template.Template
 
 func readTemplate(filename string) *template.Template {
 	t := template.New(filename)
@@ -96,6 +96,9 @@ func test(t *testing.T, mode Mode) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	if templateTxt == nil {
+		templateTxt = readTemplate("template.txt")
+	}
 
 	// test packages
 	for _, pkg := range pkgs {

src/go/parser/performance_test.go

@@ -10,17 +10,12 @@ import (
 	"testing"
 )
 
-var src = readFile("parser.go")
-
-func readFile(filename string) []byte {
-	data, err := ioutil.ReadFile(filename)
-	if err != nil {
-		panic(err)
-	}
-	return data
-}
-
 func BenchmarkParse(b *testing.B) {
+	src, err := ioutil.ReadFile("parser.go")
+	if err != nil {
+		b.Fatal(err)
+	}
+	b.ResetTimer()
 	b.SetBytes(int64(len(src)))
 	for i := 0; i < b.N; i++ {
 		if _, err := ParseFile(token.NewFileSet(), "", src, ParseComments); err != nil {

src/go/printer/nodes.go

@@ -733,7 +733,7 @@ func (p *printer) expr1(expr ast.Expr, prec1, depth int) {
 
 	case *ast.FuncLit:
 		p.expr(x.Type)
-		p.adjBlock(p.distanceFrom(x.Type.Pos()), blank, x.Body)
+		p.funcBody(p.distanceFrom(x.Type.Pos()), blank, x.Body)
 
 	case *ast.ParenExpr:
 		if _, hasParens := x.X.(*ast.ParenExpr); hasParens {
@@ -825,6 +825,7 @@ func (p *printer) expr1(expr ast.Expr, prec1, depth int) {
 		if x.Type != nil {
 			p.expr1(x.Type, token.HighestPrec, depth)
 		}
+		p.level++
 		p.print(x.Lbrace, token.LBRACE)
 		p.exprList(x.Lbrace, x.Elts, 1, commaTerm, x.Rbrace)
 		// do not insert extra line break following a /*-style comment
@@ -837,6 +838,7 @@ func (p *printer) expr1(expr ast.Expr, prec1, depth int) {
 			mode |= noExtraBlank
 		}
 		p.print(mode, x.Rbrace, token.RBRACE, mode)
+		p.level--
 
 	case *ast.Ellipsis:
 		p.print(token.ELLIPSIS)
@@ -1557,18 +1559,23 @@ func (p *printer) bodySize(b *ast.BlockStmt, maxSize int) int {
 	return bodySize
 }
 
-// adjBlock prints an "adjacent" block (e.g., a for-loop or function body) following
-// a header (e.g., a for-loop control clause or function signature) of given headerSize.
+// funcBody prints a function body following a function header of given headerSize.
 // If the header's and block's size are "small enough" and the block is "simple enough",
 // the block is printed on the current line, without line breaks, spaced from the header
 // by sep. Otherwise the block's opening "{" is printed on the current line, followed by
 // lines for the block's statements and its closing "}".
 //
-func (p *printer) adjBlock(headerSize int, sep whiteSpace, b *ast.BlockStmt) {
+func (p *printer) funcBody(headerSize int, sep whiteSpace, b *ast.BlockStmt) {
 	if b == nil {
 		return
 	}
 
+	// save/restore composite literal nesting level
+	defer func(level int) {
+		p.level = level
+	}(p.level)
+	p.level = 0
+
 	const maxSize = 100
 	if headerSize+p.bodySize(b, maxSize) <= maxSize {
 		p.print(sep, b.Lbrace, token.LBRACE)
@@ -1613,7 +1620,7 @@ func (p *printer) funcDecl(d *ast.FuncDecl) {
 	}
 	p.expr(d.Name)
 	p.signature(d.Type.Params, d.Type.Results)
-	p.adjBlock(p.distanceFrom(d.Pos()), vtab, d.Body)
+	p.funcBody(p.distanceFrom(d.Pos()), vtab, d.Body)
 }
 
 func (p *printer) decl(decl ast.Decl) {

src/go/printer/printer.go

@@ -58,6 +58,7 @@ type printer struct {
 	// Current state
 	output      []byte       // raw printer result
 	indent      int          // current indentation
+	level       int          // level == 0: outside composite literal; level > 0: inside composite literal
 	mode        pmode        // current printer mode
 	impliedSemi bool         // if set, a linebreak implies a semicolon
 	lastTok     token.Token  // last token printed (token.ILLEGAL if it's whitespace)
@@ -744,15 +745,19 @@ func (p *printer) intersperseComments(next token.Position, tok token.Token) (wro
 		// follows on the same line but is not a comma, and not a "closing"
 		// token immediately following its corresponding "opening" token,
 		// add an extra separator unless explicitly disabled. Use a blank
-		// as separator unless we have pending linebreaks and they are not
-		// disabled, in which case we want a linebreak (issue 15137).
+		// as separator unless we have pending linebreaks, they are not
+		// disabled, and we are outside a composite literal, in which case
+		// we want a linebreak (issue 15137).
+		// TODO(gri) This has become overly complicated. We should be able
+		// to track whether we're inside an expression or statement and
+		// use that information to decide more directly.
 		needsLinebreak := false
 		if p.mode&noExtraBlank == 0 &&
 			last.Text[1] == '*' && p.lineFor(last.Pos()) == next.Line &&
 			tok != token.COMMA &&
 			(tok != token.RPAREN || p.prevOpen == token.LPAREN) &&
 			(tok != token.RBRACK || p.prevOpen == token.LBRACK) {
-			if p.containsLinebreak() && p.mode&noExtraLinebreak == 0 {
+			if p.containsLinebreak() && p.mode&noExtraLinebreak == 0 && p.level == 0 {
 				needsLinebreak = true
 			} else {
 				p.writeByte(' ', 1)

src/go/printer/testdata/comments2.golden

@@ -103,3 +103,62 @@ label:
 	mask := uint64(1)<<c - 1		// Allocation mask
 	used := atomic.LoadUint64(&h.used)	// Current allocations
 }
+
+// Test cases for issue 18782
+var _ = [][]int{
+	/*       a, b, c, d, e */
+	/* a */ {0, 0, 0, 0, 0},
+	/* b */ {0, 5, 4, 4, 4},
+	/* c */ {0, 4, 5, 4, 4},
+	/* d */ {0, 4, 4, 5, 4},
+	/* e */ {0, 4, 4, 4, 5},
+}
+
+var _ = T{ /* a */ 0}
+
+var _ = T{ /* a */ /* b */ 0}
+
+var _ = T{	/* a */	/* b */
+	/* c */ 0,
+}
+
+var _ = T{	/* a */	/* b */
+	/* c */
+	/* d */ 0,
+}
+
+var _ = T{
+	/* a */
+	/* b */ 0,
+}
+
+var _ = T{ /* a */ {}}
+
+var _ = T{ /* a */ /* b */ {}}
+
+var _ = T{	/* a */	/* b */
+	/* c */ {},
+}
+
+var _ = T{	/* a */	/* b */
+	/* c */
+	/* d */ {},
+}
+
+var _ = T{
+	/* a */
+	/* b */ {},
+}
+
+var _ = []T{
+	func() {
+		var _ = [][]int{
+			/*       a, b, c, d, e */
+			/* a */ {0, 0, 0, 0, 0},
+			/* b */ {0, 5, 4, 4, 4},
+			/* c */ {0, 4, 5, 4, 4},
+			/* d */ {0, 4, 4, 5, 4},
+			/* e */ {0, 4, 4, 4, 5},
+		}
+	},
+}

src/go/printer/testdata/comments2.input

@@ -103,3 +103,66 @@ label:
    mask := uint64(1)<<c - 1 // Allocation mask
    used := atomic.LoadUint64(&h.used) // Current allocations
 }
+
+// Test cases for issue 18782
+var _ = [][]int{
+   /*       a, b, c, d, e */
+   /* a */ {0, 0, 0, 0, 0},
+   /* b */ {0, 5, 4, 4, 4},
+   /* c */ {0, 4, 5, 4, 4},
+   /* d */ {0, 4, 4, 5, 4},
+   /* e */ {0, 4, 4, 4, 5},
+}
+
+var _ = T{ /* a */ 0,
+}
+
+var _ = T{ /* a */ /* b */ 0,
+}
+
+var _ = T{ /* a */ /* b */
+   /* c */ 0,
+}
+
+var _ = T{ /* a */ /* b */
+   /* c */
+   /* d */ 0,
+}
+
+var _ = T{
+   /* a */
+   /* b */ 0,
+}
+
+var _ = T{ /* a */ {},
+}
+
+var _ = T{ /* a */ /* b */ {},
+}
+
+var _ = T{ /* a */ /* b */
+   /* c */ {},
+}
+
+var _ = T{ /* a */ /* b */
+   /* c */
+   /* d */ {},
+}
+
+var _ = T{
+   /* a */
+   /* b */ {},
+}
+
+var _ = []T{
+   func() {
+      var _ = [][]int{
+         /*       a, b, c, d, e */
+         /* a */ {0, 0, 0, 0, 0},
+         /* b */ {0, 5, 4, 4, 4},
+         /* c */ {0, 4, 5, 4, 4},
+         /* d */ {0, 4, 4, 5, 4},
+         /* e */ {0, 4, 4, 4, 5},
+      }
+   },
+}

src/net/http/client.go

@@ -413,11 +413,12 @@ func (c *Client) checkRedirect(req *Request, via []*Request) error {
 
 // redirectBehavior describes what should happen when the
 // client encounters a 3xx status code from the server
-func redirectBehavior(reqMethod string, resp *Response, ireq *Request) (redirectMethod string, shouldRedirect bool) {
+func redirectBehavior(reqMethod string, resp *Response, ireq *Request) (redirectMethod string, shouldRedirect, includeBody bool) {
 	switch resp.StatusCode {
 	case 301, 302, 303:
 		redirectMethod = reqMethod
 		shouldRedirect = true
+		includeBody = false
 
 		// RFC 2616 allowed automatic redirection only with GET and
 		// HEAD requests. RFC 7231 lifts this restriction, but we still
@@ -429,6 +430,7 @@ func redirectBehavior(reqMethod string, resp *Response, ireq *Request) (redirect
 	case 307, 308:
 		redirectMethod = reqMethod
 		shouldRedirect = true
+		includeBody = true
 
 		// Treat 307 and 308 specially, since they're new in
 		// Go 1.8, and they also require re-sending the request body.
@@ -449,7 +451,7 @@ func redirectBehavior(reqMethod string, resp *Response, ireq *Request) (redirect
 			shouldRedirect = false
 		}
 	}
-	return redirectMethod, shouldRedirect
+	return redirectMethod, shouldRedirect, includeBody
 }
 
 // Do sends an HTTP request and returns an HTTP response, following
@@ -492,11 +494,14 @@ func (c *Client) Do(req *Request) (*Response, error) {
 	}
 
 	var (
-		deadline       = c.deadline()
-		reqs           []*Request
-		resp           *Response
-		copyHeaders    = c.makeHeadersCopier(req)
+		deadline    = c.deadline()
+		reqs        []*Request
+		resp        *Response
+		copyHeaders = c.makeHeadersCopier(req)
+
+		// Redirect behavior:
 		redirectMethod string
+		includeBody    bool
 	)
 	uerr := func(err error) error {
 		req.closeBody()
@@ -534,7 +539,7 @@ func (c *Client) Do(req *Request) (*Response, error) {
 				Cancel:   ireq.Cancel,
 				ctx:      ireq.ctx,
 			}
-			if ireq.GetBody != nil {
+			if includeBody && ireq.GetBody != nil {
 				req.Body, err = ireq.GetBody()
 				if err != nil {
 					return nil, uerr(err)
@@ -598,7 +603,7 @@ func (c *Client) Do(req *Request) (*Response, error) {
 		}
 
 		var shouldRedirect bool
-		redirectMethod, shouldRedirect = redirectBehavior(req.Method, resp, reqs[0])
+		redirectMethod, shouldRedirect, includeBody = redirectBehavior(req.Method, resp, reqs[0])
 		if !shouldRedirect {
 			return resp, nil
 		}

src/net/http/client_test.go

@@ -360,25 +360,25 @@ func TestPostRedirects(t *testing.T) {
 	wantSegments := []string{
 		`POST / "first"`,
 		`POST /?code=301&next=302 "c301"`,
-		`GET /?code=302 "c301"`,
-		`GET / "c301"`,
+		`GET /?code=302 ""`,
+		`GET / ""`,
 		`POST /?code=302&next=302 "c302"`,
-		`GET /?code=302 "c302"`,
-		`GET / "c302"`,
+		`GET /?code=302 ""`,
+		`GET / ""`,
 		`POST /?code=303&next=301 "c303wc301"`,
-		`GET /?code=301 "c303wc301"`,
-		`GET / "c303wc301"`,
+		`GET /?code=301 ""`,
+		`GET / ""`,
 		`POST /?code=304 "c304"`,
 		`POST /?code=305 "c305"`,
 		`POST /?code=307&next=303,308,302 "c307"`,
 		`POST /?code=303&next=308,302 "c307"`,
-		`GET /?code=308&next=302 "c307"`,
+		`GET /?code=308&next=302 ""`,
 		`GET /?code=302 "c307"`,
-		`GET / "c307"`,
+		`GET / ""`,
 		`POST /?code=308&next=302,301 "c308"`,
 		`POST /?code=302&next=301 "c308"`,
-		`GET /?code=301 "c308"`,
-		`GET / "c308"`,
+		`GET /?code=301 ""`,
+		`GET / ""`,
 		`POST /?code=404 "c404"`,
 	}
 	want := strings.Join(wantSegments, "\n")
@@ -399,20 +399,20 @@ func TestDeleteRedirects(t *testing.T) {
 	wantSegments := []string{
 		`DELETE / "first"`,
 		`DELETE /?code=301&next=302,308 "c301"`,
-		`GET /?code=302&next=308 "c301"`,
-		`GET /?code=308 "c301"`,
+		`GET /?code=302&next=308 ""`,
+		`GET /?code=308 ""`,
 		`GET / "c301"`,
 		`DELETE /?code=302&next=302 "c302"`,
-		`GET /?code=302 "c302"`,
-		`GET / "c302"`,
+		`GET /?code=302 ""`,
+		`GET / ""`,
 		`DELETE /?code=303 "c303"`,
-		`GET / "c303"`,
+		`GET / ""`,
 		`DELETE /?code=307&next=301,308,303,302,304 "c307"`,
 		`DELETE /?code=301&next=308,303,302,304 "c307"`,
-		`GET /?code=308&next=303,302,304 "c307"`,
+		`GET /?code=308&next=303,302,304 ""`,
 		`GET /?code=303&next=302,304 "c307"`,
-		`GET /?code=302&next=304 "c307"`,
-		`GET /?code=304 "c307"`,
+		`GET /?code=302&next=304 ""`,
+		`GET /?code=304 ""`,
 		`DELETE /?code=308&next=307 "c308"`,
 		`DELETE /?code=307 "c308"`,
 		`DELETE / "c308"`,
@@ -432,7 +432,11 @@ func testRedirectsByMethod(t *testing.T, method string, table []redirectTest, wa
 	ts = httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
 		log.Lock()
 		slurp, _ := ioutil.ReadAll(r.Body)
-		fmt.Fprintf(&log.Buffer, "%s %s %q\n", r.Method, r.RequestURI, slurp)
+		fmt.Fprintf(&log.Buffer, "%s %s %q", r.Method, r.RequestURI, slurp)
+		if cl := r.Header.Get("Content-Length"); r.Method == "GET" && len(slurp) == 0 && (r.ContentLength != 0 || cl != "") {
+			fmt.Fprintf(&log.Buffer, " (but with body=%T, content-length = %v, %q)", r.Body, r.ContentLength, cl)
+		}
+		log.WriteByte('\n')
 		log.Unlock()
 		urlQuery := r.URL.Query()
 		if v := urlQuery.Get("code"); v != "" {
@@ -475,7 +479,24 @@ func testRedirectsByMethod(t *testing.T, method string, table []redirectTest, wa
 	want = strings.TrimSpace(want)
 
 	if got != want {
-		t.Errorf("Log differs.\n Got:\n%s\nWant:\n%s\n", got, want)
+		got, want, lines := removeCommonLines(got, want)
+		t.Errorf("Log differs after %d common lines.\n\nGot:\n%s\n\nWant:\n%s\n", lines, got, want)
+	}
+}
+
+func removeCommonLines(a, b string) (asuffix, bsuffix string, commonLines int) {
+	for {
+		nl := strings.IndexByte(a, '\n')
+		if nl < 0 {
+			return a, b, commonLines
+		}
+		line := a[:nl+1]
+		if !strings.HasPrefix(b, line) {
+			return a, b, commonLines
+		}
+		commonLines++
+		a = a[len(line):]
+		b = b[len(line):]
 	}
 }
 

src/net/http/serve_test.go

@@ -5173,3 +5173,142 @@ func TestServerDuplicateBackgroundRead(t *testing.T) {
 	}
 	wg.Wait()
 }
+
+// Test that the bufio.Reader returned by Hijack includes any buffered
+// byte (from the Server's backgroundRead) in its buffer. We want the
+// Handler code to be able to tell that a byte is available via
+// bufio.Reader.Buffered(), without resorting to Reading it
+// (potentially blocking) to get at it.
+func TestServerHijackGetsBackgroundByte(t *testing.T) {
+	if runtime.GOOS == "plan9" {
+		t.Skip("skipping test; see https://golang.org/issue/18657")
+	}
+	setParallel(t)
+	defer afterTest(t)
+	done := make(chan struct{})
+	inHandler := make(chan bool, 1)
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		defer close(done)
+
+		// Tell the client to send more data after the GET request.
+		inHandler <- true
+
+		// Wait until the HTTP server sees the extra data
+		// after the GET request. The HTTP server fires the
+		// close notifier here, assuming it's a pipelined
+		// request, as documented.
+		select {
+		case <-w.(CloseNotifier).CloseNotify():
+		case <-time.After(5 * time.Second):
+			t.Error("timeout")
+			return
+		}
+
+		conn, buf, err := w.(Hijacker).Hijack()
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		defer conn.Close()
+		n := buf.Reader.Buffered()
+		if n != 1 {
+			t.Errorf("buffered data = %d; want 1", n)
+		}
+		peek, err := buf.Reader.Peek(3)
+		if string(peek) != "foo" || err != nil {
+			t.Errorf("Peek = %q, %v; want foo, nil", peek, err)
+		}
+	}))
+	defer ts.Close()
+
+	cn, err := net.Dial("tcp", ts.Listener.Addr().String())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer cn.Close()
+	if _, err := cn.Write([]byte("GET / HTTP/1.1\r\nHost: e.com\r\n\r\n")); err != nil {
+		t.Fatal(err)
+	}
+	<-inHandler
+	if _, err := cn.Write([]byte("foo")); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := cn.(*net.TCPConn).CloseWrite(); err != nil {
+		t.Fatal(err)
+	}
+	select {
+	case <-done:
+	case <-time.After(2 * time.Second):
+		t.Error("timeout")
+	}
+}
+
+// Like TestServerHijackGetsBackgroundByte above but sending a
+// immediate 1MB of data to the server to fill up the server's 4KB
+// buffer.
+func TestServerHijackGetsBackgroundByte_big(t *testing.T) {
+	if runtime.GOOS == "plan9" {
+		t.Skip("skipping test; see https://golang.org/issue/18657")
+	}
+	setParallel(t)
+	defer afterTest(t)
+	done := make(chan struct{})
+	const size = 8 << 10
+	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		defer close(done)
+
+		// Wait until the HTTP server sees the extra data
+		// after the GET request. The HTTP server fires the
+		// close notifier here, assuming it's a pipelined
+		// request, as documented.
+		select {
+		case <-w.(CloseNotifier).CloseNotify():
+		case <-time.After(5 * time.Second):
+			t.Error("timeout")
+			return
+		}
+
+		conn, buf, err := w.(Hijacker).Hijack()
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		defer conn.Close()
+		slurp, err := ioutil.ReadAll(buf.Reader)
+		if err != nil {
+			t.Errorf("Copy: %v", err)
+		}
+		allX := true
+		for _, v := range slurp {
+			if v != 'x' {
+				allX = false
+			}
+		}
+		if len(slurp) != size {
+			t.Errorf("read %d; want %d", len(slurp), size)
+		} else if !allX {
+			t.Errorf("read %q; want %d 'x'", slurp, size)
+		}
+	}))
+	defer ts.Close()
+
+	cn, err := net.Dial("tcp", ts.Listener.Addr().String())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer cn.Close()
+	if _, err := fmt.Fprintf(cn, "GET / HTTP/1.1\r\nHost: e.com\r\n\r\n%s",
+		strings.Repeat("x", size)); err != nil {
+		t.Fatal(err)
+	}
+	if err := cn.(*net.TCPConn).CloseWrite(); err != nil {
+		t.Fatal(err)
+	}
+
+	select {
+	case <-done:
+	case <-time.After(2 * time.Second):
+		t.Error("timeout")
+	}
+}

src/net/http/server.go

@@ -164,7 +164,7 @@ type Flusher interface {
 // should always test for this ability at runtime.
 type Hijacker interface {
 	// Hijack lets the caller take over the connection.
-	// After a call to Hijack(), the HTTP server library
+	// After a call to Hijack the HTTP server library
 	// will not do anything else with the connection.
 	//
 	// It becomes the caller's responsibility to manage
@@ -174,6 +174,9 @@ type Hijacker interface {
 	// already set, depending on the configuration of the
 	// Server. It is the caller's responsibility to set
 	// or clear those deadlines as needed.
+	//
+	// The returned bufio.Reader may contain unprocessed buffered
+	// data from the client.
 	Hijack() (net.Conn, *bufio.ReadWriter, error)
 }
 
@@ -293,6 +296,11 @@ func (c *conn) hijackLocked() (rwc net.Conn, buf *bufio.ReadWriter, err error) {
 	rwc.SetDeadline(time.Time{})
 
 	buf = bufio.NewReadWriter(c.bufr, bufio.NewWriter(rwc))
+	if c.r.hasByte {
+		if _, err := c.bufr.Peek(c.bufr.Buffered() + 1); err != nil {
+			return nil, nil, fmt.Errorf("unexpected Peek failure reading buffered byte: %v", err)
+		}
+	}
 	c.setState(rwc, StateHijacked)
 	return
 }

src/net/http/transport_test.go

@@ -36,6 +36,7 @@ import (
 	"strconv"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 )
@@ -2545,6 +2546,13 @@ type closerFunc func() error
 
 func (f closerFunc) Close() error { return f() }
 
+type writerFuncConn struct {
+	net.Conn
+	write func(p []byte) (n int, err error)
+}
+
+func (c writerFuncConn) Write(p []byte) (n int, err error) { return c.write(p) }
+
 // Issue 4677. If we try to reuse a connection that the server is in the
 // process of closing, we may end up successfully writing out our request (or a
 // portion of our request) only to find a connection error when we try to read
@@ -2557,66 +2565,78 @@ func (f closerFunc) Close() error { return f() }
 func TestRetryIdempotentRequestsOnError(t *testing.T) {
 	defer afterTest(t)
 
+	var (
+		mu     sync.Mutex
+		logbuf bytes.Buffer
+	)
+	logf := func(format string, args ...interface{}) {
+		mu.Lock()
+		defer mu.Unlock()
+		fmt.Fprintf(&logbuf, format, args...)
+		logbuf.WriteByte('\n')
+	}
+
 	ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
+		logf("Handler")
+		w.Header().Set("X-Status", "ok")
 	}))
 	defer ts.Close()
 
-	tr := &Transport{}
+	var writeNumAtomic int32
+	tr := &Transport{
+		Dial: func(network, addr string) (net.Conn, error) {
+			logf("Dial")
+			c, err := net.Dial(network, ts.Listener.Addr().String())
+			if err != nil {
+				logf("Dial error: %v", err)
+				return nil, err
+			}
+			return &writerFuncConn{
+				Conn: c,
+				write: func(p []byte) (n int, err error) {
+					if atomic.AddInt32(&writeNumAtomic, 1) == 2 {
+						logf("intentional write failure")
+						return 0, errors.New("second write fails")
+					}
+					logf("Write(%q)", p)
+					return c.Write(p)
+				},
+			}, nil
+		},
+	}
+	defer tr.CloseIdleConnections()
 	c := &Client{Transport: tr}
 
-	const N = 2
-	retryc := make(chan struct{}, N)
 	SetRoundTripRetried(func() {
-		retryc <- struct{}{}
+		logf("Retried.")
 	})
 	defer SetRoundTripRetried(nil)
 
-	for n := 0; n < 100; n++ {
-		// open 2 conns
-		errc := make(chan error, N)
-		for i := 0; i < N; i++ {
-			// start goroutines, send on errc
-			go func() {
-				res, err := c.Get(ts.URL)
-				if err == nil {
-					res.Body.Close()
-				}
-				errc <- err
-			}()
-		}
-		for i := 0; i < N; i++ {
-			if err := <-errc; err != nil {
-				t.Fatal(err)
-			}
-		}
-
-		ts.CloseClientConnections()
-		for i := 0; i < N; i++ {
-			go func() {
-				res, err := c.Get(ts.URL)
-				if err == nil {
-					res.Body.Close()
-				}
-				errc <- err
-			}()
-		}
-
-		for i := 0; i < N; i++ {
-			if err := <-errc; err != nil {
-				t.Fatal(err)
-			}
-		}
-		for i := 0; i < N; i++ {
-			select {
-			case <-retryc:
-				// we triggered a retry, test was successful
-				t.Logf("finished after %d runs\n", n)
-				return
-			default:
-			}
+	for i := 0; i < 3; i++ {
+		res, err := c.Get("http://fake.golang/")
+		if err != nil {
+			t.Fatalf("i=%d: Get = %v", i, err)
 		}
+		res.Body.Close()
+	}
+
+	mu.Lock()
+	got := logbuf.String()
+	mu.Unlock()
+	const want = `Dial
+Write("GET / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nAccept-Encoding: gzip\r\n\r\n")
+Handler
+intentional write failure
+Retried.
+Dial
+Write("GET / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nAccept-Encoding: gzip\r\n\r\n")
+Handler
+Write("GET / HTTP/1.1\r\nHost: fake.golang\r\nUser-Agent: Go-http-client/1.1\r\nAccept-Encoding: gzip\r\n\r\n")
+Handler
+`
+	if got != want {
+		t.Errorf("Log of events differs. Got:\n%s\nWant:\n%s", got, want)
 	}
-	t.Fatal("did not trigger any retries")
 }
 
 // Issue 6981

src/os/os_test.go

@@ -54,12 +54,15 @@ var sysdir = func() *sysDir {
 	case "darwin":
 		switch runtime.GOARCH {
 		case "arm", "arm64":
+			/// At this point the test harness has not had a chance
+			// to move us into the ./src/os directory, so the
+			// current working directory is the root of the app.
 			wd, err := syscall.Getwd()
 			if err != nil {
 				wd = err.Error()
 			}
 			return &sysDir{
-				filepath.Join(wd, "..", ".."),
+				wd,
 				[]string{
 					"ResourceRules.plist",
 					"Info.plist",

src/reflect/all_test.go

@@ -26,6 +26,8 @@ import (
 	"unsafe"
 )
 
+var sink interface{}
+
 func TestBool(t *testing.T) {
 	v := ValueOf(true)
 	if v.Bool() != true {
@@ -5331,6 +5333,72 @@ func TestCallGC(t *testing.T) {
 	f2("four", "five5", "six666", "seven77", "eight888")
 }
 
+// Issue 18635 (function version).
+func TestKeepFuncLive(t *testing.T) {
+	// Test that we keep makeFuncImpl live as long as it is
+	// referenced on the stack.
+	typ := TypeOf(func(i int) {})
+	var f, g func(in []Value) []Value
+	f = func(in []Value) []Value {
+		clobber()
+		i := int(in[0].Int())
+		if i > 0 {
+			// We can't use Value.Call here because
+			// runtime.call* will keep the makeFuncImpl
+			// alive. However, by converting it to an
+			// interface value and calling that,
+			// reflect.callReflect is the only thing that
+			// can keep the makeFuncImpl live.
+			//
+			// Alternate between f and g so that if we do
+			// reuse the memory prematurely it's more
+			// likely to get obviously corrupted.
+			MakeFunc(typ, g).Interface().(func(i int))(i - 1)
+		}
+		return nil
+	}
+	g = func(in []Value) []Value {
+		clobber()
+		i := int(in[0].Int())
+		MakeFunc(typ, f).Interface().(func(i int))(i)
+		return nil
+	}
+	MakeFunc(typ, f).Call([]Value{ValueOf(10)})
+}
+
+// Issue 18635 (method version).
+type KeepMethodLive struct{}
+
+func (k KeepMethodLive) Method1(i int) {
+	clobber()
+	if i > 0 {
+		ValueOf(k).MethodByName("Method2").Interface().(func(i int))(i - 1)
+	}
+}
+
+func (k KeepMethodLive) Method2(i int) {
+	clobber()
+	ValueOf(k).MethodByName("Method1").Interface().(func(i int))(i)
+}
+
+func TestKeepMethodLive(t *testing.T) {
+	// Test that we keep methodValue live as long as it is
+	// referenced on the stack.
+	KeepMethodLive{}.Method1(10)
+}
+
+// clobber tries to clobber unreachable memory.
+func clobber() {
+	runtime.GC()
+	for i := 1; i < 32; i++ {
+		for j := 0; j < 10; j++ {
+			obj := make([]*byte, i)
+			sink = obj
+		}
+	}
+	runtime.GC()
+}
+
 type funcLayoutTest struct {
 	rcvr, t                  Type
 	size, argsize, retOffset uintptr

src/reflect/value.go

@@ -538,6 +538,11 @@ func callReflect(ctxt *makeFuncImpl, frame unsafe.Pointer) {
 			off += typ.size
 		}
 	}
+
+	// runtime.getArgInfo expects to be able to find ctxt on the
+	// stack when it finds our caller, makeFuncStub. Make sure it
+	// doesn't get garbage collected.
+	runtime.KeepAlive(ctxt)
 }
 
 // methodReceiver returns information about the receiver
@@ -650,6 +655,9 @@ func callMethod(ctxt *methodValue, frame unsafe.Pointer) {
 	// though it's a heap object.
 	memclrNoHeapPointers(args, frametype.size)
 	framePool.Put(args)
+
+	// See the comment in callReflect.
+	runtime.KeepAlive(ctxt)
 }
 
 // funcName returns the name of f, for use in error messages.

src/runtime/memmove_amd64.s

@@ -146,10 +146,16 @@ move_1or2:
 move_0:
 	RET
 move_3or4:
+	CMPQ	BX, $4
+	JB	move_3
+	MOVL	(SI), AX
+	MOVL	AX, (DI)
+	RET
+move_3:
 	MOVW	(SI), AX
-	MOVW	-2(SI)(BX*1), CX
+	MOVB	2(SI), CX
 	MOVW	AX, (DI)
-	MOVW	CX, -2(DI)(BX*1)
+	MOVB	CX, 2(DI)
 	RET
 move_5through7:
 	MOVL	(SI), AX

src/runtime/memmove_test.go

@@ -6,6 +6,7 @@ package runtime_test
 
 import (
 	"crypto/rand"
+	"encoding/binary"
 	"fmt"
 	"internal/race"
 	. "runtime"
@@ -447,3 +448,22 @@ func BenchmarkCopyFat1024(b *testing.B) {
 		_ = y
 	}
 }
+
+func BenchmarkIssue18740(b *testing.B) {
+	// This tests that memmove uses one 4-byte load/store to move 4 bytes.
+	// It used to do 2 2-byte load/stores, which leads to a pipeline stall
+	// when we try to read the result with one 4-byte load.
+	var buf [4]byte
+	for j := 0; j < b.N; j++ {
+		s := uint32(0)
+		for i := 0; i < 4096; i += 4 {
+			copy(buf[:], g[i:])
+			s += binary.LittleEndian.Uint32(buf[:])
+		}
+		sink = uint64(s)
+	}
+}
+
+// TODO: 2 byte and 8 byte benchmarks also.
+
+var g [4096]byte

src/runtime/mgc.go

@@ -1129,8 +1129,6 @@ top:
 		// sitting in the per-P work caches.
 		// Flush and disable work caches.
 
-		gcMarkRootCheck()
-
 		// Disallow caching workbufs and indicate that we're in mark 2.
 		gcBlackenPromptly = true
 
@@ -1153,6 +1151,16 @@ top:
 			})
 		})
 
+		// Check that roots are marked. We should be able to
+		// do this before the forEachP, but based on issue
+		// #16083 there may be a (harmless) race where we can
+		// enter mark 2 while some workers are still scanning
+		// stacks. The forEachP ensures these scans are done.
+		//
+		// TODO(austin): Figure out the race and fix this
+		// properly.
+		gcMarkRootCheck()
+
 		// Now we can start up mark 2 workers.
 		atomic.Xaddint64(&gcController.dedicatedMarkWorkersNeeded, 0xffffffff)
 		atomic.Xaddint64(&gcController.fractionalMarkWorkersNeeded, 0xffffffff)

src/runtime/msan.go

@@ -28,9 +28,11 @@ const msanenabled = true
 // the runtime, but operations like a slice copy can call msanread
 // anyhow for values on the stack. Just ignore msanread when running
 // on the system stack. The other msan functions are fine.
+//
+//go:nosplit
 func msanread(addr unsafe.Pointer, sz uintptr) {
 	g := getg()
-	if g == g.m.g0 || g == g.m.gsignal {
+	if g == nil || g.m == nil || g == g.m.g0 || g == g.m.gsignal {
 		return
 	}
 	domsanread(addr, sz)

src/runtime/plugin.go

@@ -56,7 +56,9 @@ func plugin_lastmoduleinit() (path string, syms map[string]interface{}, mismatch
 
 	lock(&ifaceLock)
 	for _, i := range md.itablinks {
-		additab(i, true, false)
+		if i.inhash == 0 {
+			additab(i, true, false)
+		}
 	}
 	unlock(&ifaceLock)
 

src/runtime/runtime-gdb_test.go

@@ -7,6 +7,7 @@ package runtime_test
 import (
 	"bytes"
 	"fmt"
+	"go/build"
 	"internal/testenv"
 	"io/ioutil"
 	"os"
@@ -67,7 +68,6 @@ func checkGdbPython(t *testing.T) {
 }
 
 const helloSource = `
-package main
 import "fmt"
 var gslice []string
 func main() {
@@ -85,9 +85,20 @@ func main() {
 `
 
 func TestGdbPython(t *testing.T) {
+	testGdbPython(t, false)
+}
+
+func TestGdbPythonCgo(t *testing.T) {
+	testGdbPython(t, true)
+}
+
+func testGdbPython(t *testing.T, cgo bool) {
 	if runtime.GOARCH == "mips64" {
 		testenv.SkipFlaky(t, 18173)
 	}
+	if cgo && !build.Default.CgoEnabled {
+		t.Skip("skipping because cgo is not enabled")
+	}
 
 	t.Parallel()
 	checkGdbEnvironment(t)
@@ -100,8 +111,15 @@ func TestGdbPython(t *testing.T) {
 	}
 	defer os.RemoveAll(dir)
 
+	var buf bytes.Buffer
+	buf.WriteString("package main\n")
+	if cgo {
+		buf.WriteString(`import "C"` + "\n")
+	}
+	buf.WriteString(helloSource)
+
 	src := filepath.Join(dir, "main.go")
-	err = ioutil.WriteFile(src, []byte(helloSource), 0644)
+	err = ioutil.WriteFile(src, buf.Bytes(), 0644)
 	if err != nil {
 		t.Fatalf("failed to create file: %v", err)
 	}

src/runtime/symtab.go

@@ -285,6 +285,25 @@ func modulesinit() {
 			md.gcbssmask = progToPointerMask((*byte)(unsafe.Pointer(md.gcbss)), md.ebss-md.bss)
 		}
 	}
+
+	// Modules appear in the moduledata linked list in the order they are
+	// loaded by the dynamic loader, with one exception: the
+	// firstmoduledata itself the module that contains the runtime. This
+	// is not always the first module (when using -buildmode=shared, it
+	// is typically libstd.so, the second module). The order matters for
+	// typelinksinit, so we swap the first module with whatever module
+	// contains the main function.
+	//
+	// See Issue #18729.
+	mainText := funcPC(main_main)
+	for i, md := range *modules {
+		if md.text <= mainText && mainText <= md.etext {
+			(*modules)[0] = md
+			(*modules)[i] = &firstmoduledata
+			break
+		}
+	}
+
 	atomicstorep(unsafe.Pointer(&modulesSlice), unsafe.Pointer(modules))
 }
 

src/runtime/sys_linux_amd64.s

@@ -330,9 +330,9 @@ sigtrampnog:
 	// Lock sigprofCallersUse.
 	MOVL	$0, AX
 	MOVL	$1, CX
-	MOVQ	$runtime·sigprofCallersUse(SB), BX
+	MOVQ	$runtime·sigprofCallersUse(SB), R11
 	LOCK
-	CMPXCHGL	CX, 0(BX)
+	CMPXCHGL	CX, 0(R11)
 	JNZ	sigtramp  // Skip stack trace if already locked.
 
 	// Jump to the traceback function in runtime/cgo.

src/syscall/mkpost.go

@@ -18,6 +18,7 @@ import (
 	"log"
 	"os"
 	"regexp"
+	"strings"
 )
 
 func main() {
@@ -38,10 +39,16 @@ func main() {
 		re = regexp.MustCompile("Pad_cgo[A-Za-z0-9_]*")
 		s = re.ReplaceAllString(s, "_")
 
+		// We want to keep X__val in Fsid. Hide it and restore it later.
+		s = strings.Replace(s, "X__val", "MKPOSTFSIDVAL", 1)
+
 		// Replace other unwanted fields with blank identifiers.
 		re = regexp.MustCompile("X_[A-Za-z0-9_]*")
 		s = re.ReplaceAllString(s, "_")
 
+		// Restore X__val in Fsid.
+		s = strings.Replace(s, "MKPOSTFSIDVAL", "X__val", 1)
+
 		// Force the type of RawSockaddr.Data to [14]int8 to match
 		// the existing gccgo API.
 		re = regexp.MustCompile("(Data\\s+\\[14\\])uint8")

src/syscall/ztypes_linux_s390x.go

@@ -140,7 +140,7 @@ type Dirent struct {
 }
 
 type Fsid struct {
-	_ [2]int32
+	X__val [2]int32
 }
 
 type Flock_t struct {

src/testing/benchmark.go

@@ -219,7 +219,7 @@ func (b *B) run1() bool {
 	}
 	// Only print the output if we know we are not going to proceed.
 	// Otherwise it is printed in processBench.
-	if b.hasSub || b.finished {
+	if atomic.LoadInt32(&b.hasSub) != 0 || b.finished {
 		tag := "BENCH"
 		if b.skipped {
 			tag = "SKIP"
@@ -460,10 +460,13 @@ func (ctx *benchContext) processBench(b *B) {
 //
 // A subbenchmark is like any other benchmark. A benchmark that calls Run at
 // least once will not be measured itself and will be called once with N=1.
+//
+// Run may be called simultaneously from multiple goroutines, but all such
+// calls must happen before the outer benchmark function for b returns.
 func (b *B) Run(name string, f func(b *B)) bool {
 	// Since b has subbenchmarks, we will no longer run it as a benchmark itself.
 	// Release the lock and acquire it on exit to ensure locks stay paired.
-	b.hasSub = true
+	atomic.StoreInt32(&b.hasSub, 1)
 	benchmarkLock.Unlock()
 	defer benchmarkLock.Lock()
 

src/testing/sub_test.go

@@ -6,6 +6,7 @@ package testing
 
 import (
 	"bytes"
+	"fmt"
 	"regexp"
 	"strings"
 	"sync/atomic"
@@ -515,3 +516,19 @@ func TestBenchmarkOutput(t *T) {
 	Benchmark(func(b *B) { b.Error("do not print this output") })
 	Benchmark(func(b *B) {})
 }
+
+func TestParallelSub(t *T) {
+	c := make(chan int)
+	block := make(chan int)
+	for i := 0; i < 10; i++ {
+		go func(i int) {
+			<-block
+			t.Run(fmt.Sprint(i), func(t *T) {})
+			c <- 1
+		}(i)
+	}
+	close(block)
+	for i := 0; i < 10; i++ {
+		<-c
+	}
+}

src/testing/testing.go

@@ -216,6 +216,7 @@ import (
 	"strconv"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 )
 
@@ -267,8 +268,8 @@ type common struct {
 	skipped    bool         // Test of benchmark has been skipped.
 	finished   bool         // Test function has completed.
 	done       bool         // Test is finished and all subtests have completed.
-	hasSub     bool
-	raceErrors int // number of races detected during test
+	hasSub     int32        // written atomically
+	raceErrors int          // number of races detected during test
 
 	parent   *common
 	level    int       // Nesting depth of test or benchmark.
@@ -645,7 +646,7 @@ func tRunner(t *T, fn func(t *T)) {
 		// Do not lock t.done to allow race detector to detect race in case
 		// the user does not appropriately synchronizes a goroutine.
 		t.done = true
-		if t.parent != nil && !t.hasSub {
+		if t.parent != nil && atomic.LoadInt32(&t.hasSub) == 0 {
 			t.setRan()
 		}
 		t.signal <- true
@@ -659,8 +660,11 @@ func tRunner(t *T, fn func(t *T)) {
 
 // Run runs f as a subtest of t called name. It reports whether f succeeded.
 // Run will block until all its parallel subtests have completed.
+//
+// Run may be called simultaneously from multiple goroutines, but all such
+// calls must happen before the outer test function for t returns.
 func (t *T) Run(name string, f func(t *T)) bool {
-	t.hasSub = true
+	atomic.StoreInt32(&t.hasSub, 1)
 	testName, ok := t.context.match.fullName(&t.common, name)
 	if !ok {
 		return true

src/vendor/golang_org/x/crypto/poly1305/sum_amd64.s

@@ -54,9 +54,9 @@
 	ADCQ  t3, h1;                  \
 	ADCQ  $0, h2
 
-DATA poly1305Mask<>+0x00(SB)/8, $0x0FFFFFFC0FFFFFFF
-DATA poly1305Mask<>+0x08(SB)/8, $0x0FFFFFFC0FFFFFFC
-GLOBL poly1305Mask<>(SB), RODATA, $16
+DATA ·poly1305Mask<>+0x00(SB)/8, $0x0FFFFFFC0FFFFFFF
+DATA ·poly1305Mask<>+0x08(SB)/8, $0x0FFFFFFC0FFFFFFC
+GLOBL ·poly1305Mask<>(SB), RODATA, $16
 
 // func poly1305(out *[16]byte, m *byte, mlen uint64, key *[32]key)
 TEXT ·poly1305(SB), $0-32
@@ -67,8 +67,8 @@ TEXT ·poly1305(SB), $0-32
 
 	MOVQ 0(AX), R11
 	MOVQ 8(AX), R12
-	ANDQ poly1305Mask<>(SB), R11   // r0
-	ANDQ poly1305Mask<>+8(SB), R12 // r1
+	ANDQ ·poly1305Mask<>(SB), R11   // r0
+	ANDQ ·poly1305Mask<>+8(SB), R12 // r1
 	XORQ R8, R8                    // h0
 	XORQ R9, R9                    // h1
 	XORQ R10, R10                  // h2

src/vendor/golang_org/x/crypto/poly1305/sum_arm.s

@@ -9,12 +9,12 @@
 // This code was translated into a form compatible with 5a from the public
 // domain source by Andrew Moon: github.com/floodyberry/poly1305-opt/blob/master/app/extensions/poly1305.
 
-DATA poly1305_init_constants_armv6<>+0x00(SB)/4, $0x3ffffff
-DATA poly1305_init_constants_armv6<>+0x04(SB)/4, $0x3ffff03
-DATA poly1305_init_constants_armv6<>+0x08(SB)/4, $0x3ffc0ff
-DATA poly1305_init_constants_armv6<>+0x0c(SB)/4, $0x3f03fff
-DATA poly1305_init_constants_armv6<>+0x10(SB)/4, $0x00fffff
-GLOBL poly1305_init_constants_armv6<>(SB), 8, $20
+DATA ·poly1305_init_constants_armv6<>+0x00(SB)/4, $0x3ffffff
+DATA ·poly1305_init_constants_armv6<>+0x04(SB)/4, $0x3ffff03
+DATA ·poly1305_init_constants_armv6<>+0x08(SB)/4, $0x3ffc0ff
+DATA ·poly1305_init_constants_armv6<>+0x0c(SB)/4, $0x3f03fff
+DATA ·poly1305_init_constants_armv6<>+0x10(SB)/4, $0x00fffff
+GLOBL ·poly1305_init_constants_armv6<>(SB), 8, $20
 
 // Warning: the linker may use R11 to synthesize certain instructions. Please
 // take care and verify that no synthetic instructions use it.
@@ -27,7 +27,7 @@ TEXT poly1305_init_ext_armv6<>(SB), NOSPLIT, $0
 	ADD       $4, R13, R8
 	MOVM.IB   [R4-R7], (R8)
 	MOVM.IA.W (R1), [R2-R5]
-	MOVW      $poly1305_init_constants_armv6<>(SB), R7
+	MOVW      $·poly1305_init_constants_armv6<>(SB), R7
 	MOVW      R2, R8
 	MOVW      R2>>26, R9
 	MOVW      R3>>20, g

test/fixedbugs/issue18661.go

@@ -0,0 +1,18 @@
+// compile
+
+// Copyright 2017 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 p
+
+var (
+	e interface{}
+	s = struct{ a *int }{}
+	b = e == s
+)
+
+func test(obj interface{}) {
+	if obj != struct{ a *string }{} {
+	}
+}

test/fixedbugs/issue18725.go

@@ -0,0 +1,24 @@
+// run
+
+// Copyright 2017 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 main
+
+import "os"
+
+func panicWhenNot(cond bool) {
+	if cond {
+		os.Exit(0)
+	} else {
+		panic("nilcheck elim failed")
+	}
+}
+
+func main() {
+	e := (*string)(nil)
+	panicWhenNot(e == e)
+	// Should never reach this line.
+	panicWhenNot(*e == *e)
+}

test/nilptr3.go

@@ -40,23 +40,23 @@ var (
 )
 
 func f1() {
-	_ = *intp // ERROR "generated nil check"
+	_ = *intp // ERROR "removed nil check"
 
 	// This one should be removed but the block copy needs
 	// to be turned into its own pseudo-op in order to see
 	// the indirect.
-	_ = *arrayp // ERROR "generated nil check"
+	_ = *arrayp // ERROR "removed nil check"
 
 	// 0-byte indirect doesn't suffice.
 	// we don't registerize globals, so there are no removed.* nil checks.
-	_ = *array0p // ERROR "generated nil check"
 	_ = *array0p // ERROR "removed nil check"
+	_ = *array0p // ERROR "generated nil check"
 
-	_ = *intp    // ERROR "removed nil check"
+	_ = *intp    // ERROR "generated nil check"
 	_ = *arrayp  // ERROR "removed nil check"
 	_ = *structp // ERROR "generated nil check"
 	_ = *emptyp  // ERROR "generated nil check"
-	_ = *arrayp  // ERROR "removed nil check"
+	_ = *arrayp  // ERROR "generated nil check"
 }
 
 func f2() {
@@ -71,15 +71,15 @@ func f2() {
 		empty1p    *Empty1
 	)
 
-	_ = *intp       // ERROR "generated nil check"
-	_ = *arrayp     // ERROR "generated nil check"
-	_ = *array0p    // ERROR "generated nil check"
-	_ = *array0p    // ERROR "removed.* nil check"
 	_ = *intp       // ERROR "removed.* nil check"
 	_ = *arrayp     // ERROR "removed.* nil check"
+	_ = *array0p    // ERROR "removed.* nil check"
+	_ = *array0p    // ERROR "generated nil check"
+	_ = *intp       // ERROR "generated nil check"
+	_ = *arrayp     // ERROR "removed.* nil check"
 	_ = *structp    // ERROR "generated nil check"
 	_ = *emptyp     // ERROR "generated nil check"
-	_ = *arrayp     // ERROR "removed.* nil check"
+	_ = *arrayp     // ERROR "generated nil check"
 	_ = *bigarrayp  // ERROR "generated nil check" ARM removed nil check before indirect!!
 	_ = *bigstructp // ERROR "generated nil check"
 	_ = *empty1p    // ERROR "generated nil check"
@@ -122,16 +122,16 @@ func f3(x *[10000]int) {
 	// x wasn't going to change across the function call.
 	// But it's a little complex to do and in practice doesn't
 	// matter enough.
-	_ = x[9999] // ERROR "removed nil check"
+	_ = x[9999] // ERROR "generated nil check" // TODO: fix
 }
 
 func f3a() {
 	x := fx10k()
 	y := fx10k()
 	z := fx10k()
-	_ = &x[9] // ERROR "generated nil check"
-	y = z
 	_ = &x[9] // ERROR "removed.* nil check"
+	y = z
+	_ = &x[9] // ERROR "generated nil check"
 	x = y
 	_ = &x[9] // ERROR "generated nil check"
 }
@@ -139,11 +139,11 @@ func f3a() {
 func f3b() {
 	x := fx10k()
 	y := fx10k()
-	_ = &x[9] // ERROR "generated nil check"
+	_ = &x[9] // ERROR "removed.* nil check"
 	y = x
 	_ = &x[9] // ERROR "removed.* nil check"
 	x = y
-	_ = &x[9] // ERROR "removed.* nil check"
+	_ = &x[9] // ERROR "generated nil check"
 }
 
 func fx10() *[10]int
@@ -179,15 +179,15 @@ func f4(x *[10]int) {
 	_ = x[9] // ERROR "generated nil check"  // bug would like to remove before indirect
 
 	fx10()
-	_ = x[9] // ERROR "removed nil check"
+	_ = x[9] // ERROR "generated nil check"  // TODO: fix
 
 	x = fx10()
 	y := fx10()
-	_ = &x[9] // ERROR "generated nil check"
+	_ = &x[9] // ERROR "removed[a-z ]* nil check"
 	y = x
 	_ = &x[9] // ERROR "removed[a-z ]* nil check"
 	x = y
-	_ = &x[9] // ERROR "removed[a-z ]* nil check"
+	_ = &x[9] // ERROR "generated nil check"
 }
 
 func f5(p *float32, q *float64, r *float32, s *float64) float64 {