[release-branch.go1.12] go1.12.2

Change-Id: I07e4404196886b7754414726f25092cca39861a7
Reviewed-on: https://go-review.googlesource.com/c/go/+/170888
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

VERSION

@@ -0,0 +1 @@
+go1.12.2

doc/cmd.html

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

doc/contrib.html

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

doc/devel/release.html

@@ -23,6 +23,31 @@ in supported releases as needed by issuing minor revisions
 (for example, Go 1.6.1, Go 1.6.2, and so on).
 </p>
 
+<h2 id="go1.12">go1.12 (released 2019/02/25)</h2>
+
+<p>
+Go 1.12 is a major release of Go.
+Read the <a href="/doc/go1.12">Go 1.12 Release Notes</a> for more information.
+</p>
+
+<h3 id="go1.12.minor">Minor revisions</h3>
+
+<p>
+go1.12.1 (released 2019/03/14) includes fixes to cgo, the compiler, the go
+command, and the <code>fmt</code>, <code>net/smtp</code>, <code>os</code>,
+<code>path/filepath</code>, <code>sync</code>, and <code>text/template</code>
+packages. See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.1">Go
+1.12.1 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.12.2 (released 2019/04/05) includes fixes to the compiler, the go
+command, the runtime, and the <code>doc</code>, <code>net</code>,
+<code>net/http/httputil</code>, and <code>os</code> packages. See the
+<a href="https://github.com/golang/go/issues?q=milestone%3AGo1.12.2">Go
+1.12.2 milestone</a> on our issue tracker for details.
+</p>
+
 <h2 id="go1.11">go1.11 (released 2018/08/24)</h2>
 
 <p>
@@ -66,6 +91,28 @@ See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.4+labe
 1.11.4 milestone</a> on our issue tracker for details.
 </p>
 
+<p>
+go1.11.5 (released 2019/01/23) includes a security fix to the
+<code>crypto/elliptic</code> package.  See
+the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.5">Go
+1.11.5 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.11.6 (released 2019/03/14) includes fixes to cgo, the compiler, linker,
+runtime, go command, and the <code>crypto/x509</code>, <code>encoding/json</code>,
+<code>net</code>, and <code>net/url</code> packages. See the
+<a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.6">Go
+1.11.6 milestone</a> on our issue tracker for details.
+</p>
+
+<p>
+go1.11.7 (released 2019/04/05) includes fixes to the runtime and the
+<code>net</code> packages. See the
+<a href="https://github.com/golang/go/issues?q=milestone%3AGo1.11.7">Go
+1.11.7 milestone</a> on our issue tracker for details.
+</p>
+
 <h2 id="go1.10">go1.10 (released 2018/02/16)</h2>
 
 <p>
@@ -131,6 +178,13 @@ See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.10.7+labe
 Go 1.10.7 milestone</a> on our issue tracker for details.
 </p>
 
+<p>
+go1.10.8 (released 2019/01/23) includes a security fix to the
+<code>crypto/elliptic</code> package.  See
+the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.10.8">Go
+1.10.8 milestone</a> on our issue tracker for details.
+</p>
+
 <h2 id="go1.9">go1.9 (released 2017/08/24)</h2>
 
 <p>

doc/go1.12.html

@@ -15,14 +15,7 @@ Do not send CLs removing the interior tags from such phrases.
   ul li { margin: 0.5em 0; }
 </style>
 
-<h2 id="introduction">DRAFT RELEASE NOTES - Introduction to Go 1.12</h2>
-
-<p>
-  <strong>
-    Go 1.12 is not yet released. These are work-in-progress
-    release notes. Go 1.12 is expected to be released in February 2019.
-  </strong>
-</p>
+<h2 id="introduction">Introduction to Go 1.12</h2>
 
 <p>
   The latest Go release, version 1.12, arrives six months after <a href="go1.11">Go 1.11</a>.
@@ -109,7 +102,7 @@ Do not send CLs removing the interior tags from such phrases.
   is no longer available with <code>go vet</code>. Checking for
   variable shadowing may now be done using
 <pre>
-go install golang.org/x/tools/go/analysis/passes/shadow/cmd/shadow
+go get -u golang.org/x/tools/go/analysis/passes/shadow/cmd/shadow
 go vet -vettool=$(which shadow)
 </pre>
 </p>
@@ -121,7 +114,7 @@ The Go tour is no longer included in the main binary distribution. To
 run the tour locally, instead of running <code>go</code> <code>tool</code> <code>tour</code>,
 manually install it:
 <pre>
-go install golang.org/x/tour
+go get -u golang.org/x/tour
 tour
 </pre>
 </p>
@@ -192,6 +185,17 @@ tour
   that build fails.
 </p>
 
+<p><!-- CL 147282, 147281 -->
+  This changed use of the <code>go</code> directive means that if you
+  use Go 1.12 to build a module, thus recording <code>go 1.12</code>
+  in the <code>go.mod</code> file, you will get an error when
+  attempting to build the same module with Go 1.11 through Go 1.11.3.
+  Go 1.11.4 or later will work fine, as will releases older than Go 1.11.
+  If you must use Go 1.11 through 1.11.3, you can avoid the problem by
+  setting the language version to 1.11, using the Go 1.12 go tool,
+  via <code>go mod edit -go=1.11</code>.
+</p>
+
 <p><!-- CL 152739 -->
   When an import cannot be resolved using the active modules,
   the <code>go</code> command will now try to use the modules mentioned in the
@@ -303,7 +307,9 @@ for {
 <p>
   In Go 1.12, <code>godoc</code> no longer has a command-line interface and
   is only a web server. Users should use <code>go</code> <code>doc</code>
-  for command-line help output instead.
+  for command-line help output instead. Go 1.12 is the last release that will
+  include the <code>godoc</code> webserver; in Go 1.13 it will be available
+  via <code>go</code> <code>get</code>.
 </p>
 
 <p><!-- CL 141977 -->
@@ -493,8 +499,11 @@ for {
 <dl id="crypto/rc4"><dt><a href="/pkg/crypto/rc4/">crypto/rc4</a></dt>
   <dd>
     <p><!-- CL 130397 -->
-      This release removes the optimized assembly implementations. RC4 is insecure
-      and should only be used for compatibility with legacy systems.
+      This release removes the assembly implementations, leaving only
+      the pure Go version. The Go compiler generates code that is
+      either slightly better or slightly worse, depending on the exact
+      CPU. RC4 is insecure and should only be used for compatibility
+      with legacy systems.
     </p>
 
 </dl><!-- crypto/rc4 -->
@@ -602,17 +611,6 @@ for {
 
 </dl><!-- io -->
 
-<dl id="lib/time"><dt><a href="/pkg/lib/time/">lib/time</a></dt>
-  <dd>
-    <p><!-- CL 151299 -->
-      The time zone database in <code>$GOROOT/lib/time/zoneinfo.zip</code>
-      has been updated to version 2018i. Note that this ZIP file is
-      only used if a time zone database is not provided by the operating
-      system.
-    </p>
-
-</dl><!-- lib/time -->
-
 <dl id="math"><dt><a href="/pkg/math/">math</a></dt>
   <dd>
     <p><!-- CL 153059 -->
@@ -689,6 +687,20 @@ for {
 
 </dl><!-- net/http -->
 
+<dl id="net/url"><dt><a href="/pkg/net/url/">net/url</a></dt>
+  <dd>
+    <p><!-- CL 159157, CL 160178 -->
+      <a href="/pkg/net/url/#Parse"><code>Parse</code></a>,
+      <a href="/pkg/net/url/#ParseRequestURI"><code>ParseRequestURI</code></a>,
+      and
+      <a href="/pkg/net/url/#URL.Parse"><code>URL.Parse</code></a>
+      now return an
+      error for URLs containing ASCII control characters, which includes NULL,
+      tab, and newlines.
+    </p>
+
+</dl><!-- net/url -->
+
 <dl id="net/http/httputil"><dt><a href="/pkg/net/http/httputil/">net/http/httputil</a></dt>
   <dd>
     <p><!-- CL 146437 -->
@@ -912,6 +924,17 @@ for {
     </p>
 </dl><!-- text/template -->
 
+<dl id="time"><dt><a href="/pkg/time/">time</a></dt>
+  <dd>
+    <p><!-- CL 151299 -->
+      The time zone database in <code>$GOROOT/lib/time/zoneinfo.zip</code>
+      has been updated to version 2018i. Note that this ZIP file is
+      only used if a time zone database is not provided by the operating
+      system.
+    </p>
+
+</dl><!-- time -->
+
 <dl id="unsafe"><dt><a href="/pkg/unsafe/">unsafe</a></dt>
   <dd>
     <p><!-- CL 146058 -->

doc/install-source.html

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

misc/cgo/test/testdata/issue30527.go

@@ -0,0 +1,14 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 30527: function call rewriting casts untyped
+// constants to int because of ":=" usage.
+
+package cgotest
+
+import "cgotest/issue30527"
+
+func issue30527G() {
+	issue30527.G(nil)
+}

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

@@ -0,0 +1,19 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package issue30527
+
+import "math"
+
+/*
+#include <inttypes.h>
+
+static void issue30527F(char **p, uint64_t mod, uint32_t unused) {}
+*/
+import "C"
+
+func G(p **C.char) {
+	C.issue30527F(p, math.MaxUint64, 1)
+	C.issue30527F(p, 1<<64-1, Z)
+}

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

@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package issue30527
+
+const (
+	X = 1 << iota
+	Y
+	Z
+)

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

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

src/cmd/cgo/ast.go

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

src/cmd/cgo/gcc.go

@@ -897,21 +897,16 @@ func (p *Package) rewriteCall(f *File, call *Call) (string, bool) {
 			needsUnsafe = true
 		}
 
-		// Explicitly convert untyped constants to the
-		// parameter type, to avoid a type mismatch.
-		if p.isConst(f, arg) {
-			ptype := p.rewriteUnsafe(param.Go)
+		// Use "var x T = ..." syntax to explicitly convert untyped
+		// constants to the parameter type, to avoid a type mismatch.
+		ptype := p.rewriteUnsafe(param.Go)
+
+		if !p.needsPointerCheck(f, param.Go, args[i]) || param.BadPointer {
 			if ptype != param.Go {
 				needsUnsafe = true
 			}
-			arg = &ast.CallExpr{
-				Fun:  ptype,
-				Args: []ast.Expr{arg},
-			}
-		}
-
-		if !p.needsPointerCheck(f, param.Go, args[i]) {
-			fmt.Fprintf(&sb, "_cgo%d := %s; ", i, gofmtPos(arg, origArg.Pos()))
+			fmt.Fprintf(&sb, "var _cgo%d %s = %s; ", i,
+				gofmtLine(ptype), gofmtPos(arg, origArg.Pos()))
 			continue
 		}
 
@@ -1254,47 +1249,6 @@ func (p *Package) isType(t ast.Expr) bool {
 	return false
 }
 
-// isConst reports whether x is an untyped constant expression.
-func (p *Package) isConst(f *File, x ast.Expr) bool {
-	switch x := x.(type) {
-	case *ast.BasicLit:
-		return true
-	case *ast.SelectorExpr:
-		id, ok := x.X.(*ast.Ident)
-		if !ok || id.Name != "C" {
-			return false
-		}
-		name := f.Name[x.Sel.Name]
-		if name != nil {
-			return name.IsConst()
-		}
-	case *ast.Ident:
-		return x.Name == "nil" ||
-			strings.HasPrefix(x.Name, "_Ciconst_") ||
-			strings.HasPrefix(x.Name, "_Cfconst_") ||
-			strings.HasPrefix(x.Name, "_Csconst_") ||
-			consts[x.Name]
-	case *ast.UnaryExpr:
-		return p.isConst(f, x.X)
-	case *ast.BinaryExpr:
-		return p.isConst(f, x.X) && p.isConst(f, x.Y)
-	case *ast.ParenExpr:
-		return p.isConst(f, x.X)
-	case *ast.CallExpr:
-		// Calling the builtin function complex on two untyped
-		// constants returns an untyped constant.
-		// TODO: It's possible to construct a case that will
-		// erroneously succeed if there is a local function
-		// named "complex", shadowing the builtin, that returns
-		// a numeric type. I can't think of any cases that will
-		// erroneously fail.
-		if id, ok := x.Fun.(*ast.Ident); ok && id.Name == "complex" && len(x.Args) == 2 {
-			return p.isConst(f, x.Args[0]) && p.isConst(f, x.Args[1])
-		}
-	}
-	return false
-}
-
 // isVariable reports whether x is a variable, possibly with field references.
 func (p *Package) isVariable(x ast.Expr) bool {
 	switch x := x.(type) {
@@ -2511,13 +2465,16 @@ func (c *typeConv) Type(dtype dwarf.Type, pos token.Pos) *Type {
 			// Treat this typedef as a uintptr.
 			s := *sub
 			s.Go = c.uintptr
+			s.BadPointer = true
 			sub = &s
 			// Make sure we update any previously computed type.
 			if oldType := typedef[name.Name]; oldType != nil {
 				oldType.Go = sub.Go
+				oldType.BadPointer = true
 			}
 		}
 		t.Go = name
+		t.BadPointer = sub.BadPointer
 		if unionWithPointer[sub.Go] {
 			unionWithPointer[t.Go] = true
 		}
@@ -2527,6 +2484,7 @@ func (c *typeConv) Type(dtype dwarf.Type, pos token.Pos) *Type {
 		if oldType == nil {
 			tt := *t
 			tt.Go = sub.Go
+			tt.BadPointer = sub.BadPointer
 			typedef[name.Name] = &tt
 		}
 

src/cmd/cgo/main.go

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

@@ -129,6 +129,7 @@ func TestPackagesFor(p *Package, cover *TestCover) (pmain, ptest, pxtest *Packag
 		ptest.Internal.Imports = append(imports, p.Internal.Imports...)
 		ptest.Internal.RawImports = str.StringList(rawTestImports, p.Internal.RawImports)
 		ptest.Internal.ForceLibrary = true
+		ptest.Internal.BuildInfo = ""
 		ptest.Internal.Build = new(build.Package)
 		*ptest.Internal.Build = *p.Internal.Build
 		m := map[string][]token.Position{}
@@ -186,6 +187,7 @@ func TestPackagesFor(p *Package, cover *TestCover) (pmain, ptest, pxtest *Packag
 		},
 		Internal: PackageInternal{
 			Build:      &build.Package{Name: "main"},
+			BuildInfo:  p.Internal.BuildInfo,
 			Asmflags:   p.Internal.Asmflags,
 			Gcflags:    p.Internal.Gcflags,
 			Ldflags:    p.Internal.Ldflags,
@@ -266,17 +268,8 @@ func TestPackagesFor(p *Package, cover *TestCover) (pmain, ptest, pxtest *Packag
 	pmain.Imports = pmain.Imports[:w]
 	pmain.Internal.RawImports = str.StringList(pmain.Imports)
 
-	if ptest != p {
-		// We have made modifications to the package p being tested
-		// and are rebuilding p (as ptest).
-		// Arrange to rebuild all packages q such that
-		// the test depends on q and q depends on p.
-		// This makes sure that q sees the modifications to p.
-		// Strictly speaking, the rebuild is only necessary if the
-		// modifications to p change its export metadata, but
-		// determining that is a bit tricky, so we rebuild always.
-		recompileForTest(pmain, p, ptest, pxtest)
-	}
+	// Replace pmain's transitive dependencies with test copies, as necessary.
+	recompileForTest(pmain, p, ptest, pxtest)
 
 	// Should we apply coverage analysis locally,
 	// only for this package and only for this test?
@@ -323,6 +316,14 @@ Search:
 	return stk
 }
 
+// recompileForTest copies and replaces certain packages in pmain's dependency
+// graph. This is necessary for two reasons. First, if ptest is different than
+// preal, packages that import the package under test should get ptest instead
+// of preal. This is particularly important if pxtest depends on functionality
+// exposed in test sources in ptest. Second, if there is a main package
+// (other than pmain) anywhere, we need to clear p.Internal.BuildInfo in
+// the test copy to prevent link conflicts. This may happen if both -coverpkg
+// and the command line patterns include multiple main packages.
 func recompileForTest(pmain, preal, ptest, pxtest *Package) {
 	// The "test copy" of preal is ptest.
 	// For each package that depends on preal, make a "test copy"
@@ -352,6 +353,7 @@ func recompileForTest(pmain, preal, ptest, pxtest *Package) {
 			copy(p1.Imports, p.Imports)
 			p = p1
 			p.Target = ""
+			p.Internal.BuildInfo = ""
 		}
 
 		// Update p.Internal.Imports to use test copies.
@@ -361,6 +363,13 @@ func recompileForTest(pmain, preal, ptest, pxtest *Package) {
 				p.Internal.Imports[i] = p1
 			}
 		}
+
+		// Don't compile build info from a main package. This can happen
+		// if -coverpkg patterns include main packages, since those packages
+		// are imported by pmain. See golang.org/issue/30907.
+		if p.Internal.BuildInfo != "" && p != pmain {
+			split()
+		}
 	}
 }
 

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

src/crypto/rc4/rc4.go

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

src/crypto/tls/handshake_client.go

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

src/crypto/tls/handshake_client_test.go

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

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

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

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

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

src/crypto/tls/tls.go

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

src/database/sql/driver/driver.go

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

src/internal/fmtsort/sort.go

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

src/internal/fmtsort/sort_test.go

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

src/internal/poll/fd_windows.go

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

src/net/http/httptrace/trace.go

@@ -152,7 +152,7 @@ type ClientTrace struct {
 	WroteHeaders func()
 
 	// Wait100Continue is called if the Request specified
-	// "Expected: 100-continue" and the Transport has written the
+	// "Expect: 100-continue" and the Transport has written the
 	// request headers but is waiting for "100 Continue" from the
 	// server before writing the request body.
 	Wait100Continue func()

src/net/http/httputil/reverseproxy.go

@@ -389,6 +389,11 @@ func (p *ReverseProxy) copyResponse(dst io.Writer, src io.Reader, flushInterval
 				latency: flushInterval,
 			}
 			defer mlw.stop()
+
+			// set up initial timer so headers get flushed even if body writes are delayed
+			mlw.flushPending = true
+			mlw.t = time.AfterFunc(flushInterval, mlw.delayedFlush)
+
 			dst = mlw
 		}
 	}

src/net/http/httputil/reverseproxy_test.go

@@ -9,6 +9,7 @@ package httputil
 import (
 	"bufio"
 	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -317,6 +318,47 @@ func TestReverseProxyFlushInterval(t *testing.T) {
 	}
 }
 
+func TestReverseProxyFlushIntervalHeaders(t *testing.T) {
+	const expected = "hi"
+	stopCh := make(chan struct{})
+	backend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Add("MyHeader", expected)
+		w.WriteHeader(200)
+		w.(http.Flusher).Flush()
+		<-stopCh
+	}))
+	defer backend.Close()
+	defer close(stopCh)
+
+	backendURL, err := url.Parse(backend.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	proxyHandler := NewSingleHostReverseProxy(backendURL)
+	proxyHandler.FlushInterval = time.Microsecond
+
+	frontend := httptest.NewServer(proxyHandler)
+	defer frontend.Close()
+
+	req, _ := http.NewRequest("GET", frontend.URL, nil)
+	req.Close = true
+
+	ctx, cancel := context.WithTimeout(req.Context(), 10*time.Second)
+	defer cancel()
+	req = req.WithContext(ctx)
+
+	res, err := frontend.Client().Do(req)
+	if err != nil {
+		t.Fatalf("Get: %v", err)
+	}
+	defer res.Body.Close()
+
+	if res.Header.Get("MyHeader") != expected {
+		t.Errorf("got header %q; expected %q", res.Header.Get("MyHeader"), expected)
+	}
+}
+
 func TestReverseProxyCancelation(t *testing.T) {
 	const backendResponse = "I am the backend"
 

src/net/lookup.go

@@ -262,8 +262,9 @@ func (r *Resolver) lookupIPAddr(ctx context.Context, network, host string) ([]IP
 	// only the values in context. See Issue 28600.
 	lookupGroupCtx, lookupGroupCancel := context.WithCancel(withUnexpiredValuesPreserved(ctx))
 
+	lookupKey := network + "\000" + host
 	dnsWaitGroup.Add(1)
-	ch, called := r.getLookupGroup().DoChan(host, func() (interface{}, error) {
+	ch, called := r.getLookupGroup().DoChan(lookupKey, func() (interface{}, error) {
 		defer dnsWaitGroup.Done()
 		return testHookLookupIP(lookupGroupCtx, resolverFunc, network, host)
 	})
@@ -280,7 +281,7 @@ func (r *Resolver) lookupIPAddr(ctx context.Context, network, host string) ([]IP
 		// let the lookup continue uncanceled, and let later
 		// lookups with the same key share the result.
 		// See issues 8602, 20703, 22724.
-		if r.getLookupGroup().ForgetUnshared(host) {
+		if r.getLookupGroup().ForgetUnshared(lookupKey) {
 			lookupGroupCancel()
 		} else {
 			go func() {

src/net/lookup_test.go

@@ -16,6 +16,7 @@ import (
 	"sort"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 )
@@ -253,14 +254,11 @@ func TestLookupGmailTXT(t *testing.T) {
 	}
 }
 
-var lookupGooglePublicDNSAddrTests = []struct {
-	addr, name string
-}{
-	{"8.8.8.8", ".google.com."},
-	{"8.8.4.4", ".google.com."},
-
-	{"2001:4860:4860::8888", ".google.com."},
-	{"2001:4860:4860::8844", ".google.com."},
+var lookupGooglePublicDNSAddrTests = []string{
+	"8.8.8.8",
+	"8.8.4.4",
+	"2001:4860:4860::8888",
+	"2001:4860:4860::8844",
 }
 
 func TestLookupGooglePublicDNSAddr(t *testing.T) {
@@ -272,8 +270,8 @@ func TestLookupGooglePublicDNSAddr(t *testing.T) {
 
 	defer dnsWaitGroup.Wait()
 
-	for _, tt := range lookupGooglePublicDNSAddrTests {
-		names, err := LookupAddr(tt.addr)
+	for _, ip := range lookupGooglePublicDNSAddrTests {
+		names, err := LookupAddr(ip)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -281,8 +279,8 @@ func TestLookupGooglePublicDNSAddr(t *testing.T) {
 			t.Error("got no record")
 		}
 		for _, name := range names {
-			if !strings.HasSuffix(name, tt.name) {
-				t.Errorf("got %s; want a record containing %s", name, tt.name)
+			if !strings.HasSuffix(name, ".google.com.") && !strings.HasSuffix(name, ".google.") {
+				t.Errorf("got %q; want a record ending in .google.com. or .google.", name)
 			}
 		}
 	}
@@ -658,8 +656,8 @@ func testDots(t *testing.T, mode string) {
 		t.Errorf("LookupAddr(8.8.8.8): %v (mode=%v)", err, mode)
 	} else {
 		for _, name := range names {
-			if !strings.HasSuffix(name, ".google.com.") {
-				t.Errorf("LookupAddr(8.8.8.8) = %v, want names ending in .google.com. with trailing dot (mode=%v)", names, mode)
+			if !strings.HasSuffix(name, ".google.com.") && !strings.HasSuffix(name, ".google.") {
+				t.Errorf("LookupAddr(8.8.8.8) = %v, want names ending in .google.com or .google with trailing dot (mode=%v)", names, mode)
 				break
 			}
 		}
@@ -1096,6 +1094,69 @@ func TestLookupIPAddrPreservesContextValues(t *testing.T) {
 	}
 }
 
+// Issue 30521: The lookup group should call the resolver for each network.
+func TestLookupIPAddrConcurrentCallsForNetworks(t *testing.T) {
+	origTestHookLookupIP := testHookLookupIP
+	defer func() { testHookLookupIP = origTestHookLookupIP }()
+
+	queries := [][]string{
+		{"udp", "golang.org"},
+		{"udp4", "golang.org"},
+		{"udp6", "golang.org"},
+		{"udp", "golang.org"},
+		{"udp", "golang.org"},
+	}
+	results := map[[2]string][]IPAddr{
+		{"udp", "golang.org"}: {
+			{IP: IPv4(127, 0, 0, 1)},
+			{IP: IPv6loopback},
+		},
+		{"udp4", "golang.org"}: {
+			{IP: IPv4(127, 0, 0, 1)},
+		},
+		{"udp6", "golang.org"}: {
+			{IP: IPv6loopback},
+		},
+	}
+	calls := int32(0)
+	waitCh := make(chan struct{})
+	testHookLookupIP = func(ctx context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+		// We'll block until this is called one time for each different
+		// expected result. This will ensure that the lookup group would wait
+		// for the existing call if it was to be reused.
+		if atomic.AddInt32(&calls, 1) == int32(len(results)) {
+			close(waitCh)
+		}
+		select {
+		case <-waitCh:
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		}
+		return results[[2]string{network, host}], nil
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	wg := sync.WaitGroup{}
+	for _, q := range queries {
+		network := q[0]
+		host := q[1]
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			gotIPs, err := DefaultResolver.lookupIPAddr(ctx, network, host)
+			if err != nil {
+				t.Errorf("lookupIPAddr(%v, %v): unexpected error: %v", network, host, err)
+			}
+			wantIPs := results[[2]string{network, host}]
+			if !reflect.DeepEqual(gotIPs, wantIPs) {
+				t.Errorf("lookupIPAddr(%v, %v): mismatched IPAddr results\n\tGot: %v\n\tWant: %v", network, host, gotIPs, wantIPs)
+			}
+		}()
+	}
+	wg.Wait()
+}
+
 func TestWithUnexpiredValuesPreserved(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 

src/os/path.go

@@ -62,6 +62,7 @@ func MkdirAll(path string, perm FileMode) error {
 // It removes everything it can but returns the first error
 // it encounters. If the path does not exist, RemoveAll
 // returns nil (no error).
+// If there is an error, it will be of type *PathError.
 func RemoveAll(path string) error {
 	return removeAll(path)
 }

src/os/path_unix.go

@@ -51,7 +51,7 @@ func splitPath(path string) (string, string) {
 	// Remove leading directory path
 	for i--; i >= 0; i-- {
 		if path[i] == '/' {
-			dirname = path[:i+1]
+			dirname = path[:i]
 			basename = path[i+1:]
 			break
 		}

src/os/removeall_at.go

@@ -46,13 +46,20 @@ func removeAll(path string) error {
 	}
 	defer parent.Close()
 
-	return removeAllFrom(parent, base)
+	if err := removeAllFrom(parent, base); err != nil {
+		if pathErr, ok := err.(*PathError); ok {
+			pathErr.Path = parentDir + string(PathSeparator) + pathErr.Path
+			err = pathErr
+		}
+		return err
+	}
+	return nil
 }
 
-func removeAllFrom(parent *File, path string) error {
+func removeAllFrom(parent *File, base string) error {
 	parentFd := int(parent.Fd())
 	// Simple case: if Unlink (aka remove) works, we're done.
-	err := unix.Unlinkat(parentFd, path, 0)
+	err := unix.Unlinkat(parentFd, base, 0)
 	if err == nil || IsNotExist(err) {
 		return nil
 	}
@@ -64,18 +71,21 @@ func removeAllFrom(parent *File, path string) error {
 	// whose contents need to be removed.
 	// Otherwise just return the error.
 	if err != syscall.EISDIR && err != syscall.EPERM && err != syscall.EACCES {
-		return err
+		return &PathError{"unlinkat", base, err}
 	}
 
 	// Is this a directory we need to recurse into?
 	var statInfo syscall.Stat_t
-	statErr := unix.Fstatat(parentFd, path, &statInfo, unix.AT_SYMLINK_NOFOLLOW)
+	statErr := unix.Fstatat(parentFd, base, &statInfo, unix.AT_SYMLINK_NOFOLLOW)
 	if statErr != nil {
-		return statErr
+		if IsNotExist(statErr) {
+			return nil
+		}
+		return &PathError{"fstatat", base, statErr}
 	}
 	if statInfo.Mode&syscall.S_IFMT != syscall.S_IFDIR {
-		// Not a directory; return the error from the Remove.
-		return err
+		// Not a directory; return the error from the unix.Unlinkat.
+		return &PathError{"unlinkat", base, err}
 	}
 
 	// Remove the directory's entries.
@@ -84,12 +94,13 @@ func removeAllFrom(parent *File, path string) error {
 		const request = 1024
 
 		// Open the directory to recurse into
-		file, err := openFdAt(parentFd, path)
+		file, err := openFdAt(parentFd, base)
 		if err != nil {
 			if IsNotExist(err) {
 				return nil
 			}
-			return err
+			recurseErr = &PathError{"openfdat", base, err}
+			break
 		}
 
 		names, readErr := file.Readdirnames(request)
@@ -99,12 +110,15 @@ func removeAllFrom(parent *File, path string) error {
 			if IsNotExist(readErr) {
 				return nil
 			}
-			return readErr
+			return &PathError{"readdirnames", base, readErr}
 		}
 
 		for _, name := range names {
 			err := removeAllFrom(file, name)
 			if err != nil {
+				if pathErr, ok := err.(*PathError); ok {
+					pathErr.Path = base + string(PathSeparator) + pathErr.Path
+				}
 				recurseErr = err
 			}
 		}
@@ -123,7 +137,7 @@ func removeAllFrom(parent *File, path string) error {
 	}
 
 	// Remove the directory itself.
-	unlinkError := unix.Unlinkat(parentFd, path, unix.AT_REMOVEDIR)
+	unlinkError := unix.Unlinkat(parentFd, base, unix.AT_REMOVEDIR)
 	if unlinkError == nil || IsNotExist(unlinkError) {
 		return nil
 	}
@@ -131,7 +145,7 @@ func removeAllFrom(parent *File, path string) error {
 	if recurseErr != nil {
 		return recurseErr
 	}
-	return unlinkError
+	return &PathError{"unlinkat", base, unlinkError}
 }
 
 // openFdAt opens path relative to the directory in fd.
@@ -153,7 +167,7 @@ func openFdAt(dirfd int, name string) (*File, error) {
 			continue
 		}
 
-		return nil, &PathError{"openat", name, e}
+		return nil, e
 	}
 
 	if !supportsCloseOnExec {

src/os/removeall_test.go

@@ -294,7 +294,7 @@ func TestRemoveReadOnlyDir(t *testing.T) {
 }
 
 // Issue #29983.
-func TestRemoveAllButReadOnly(t *testing.T) {
+func TestRemoveAllButReadOnlyAndPathError(t *testing.T) {
 	switch runtime.GOOS {
 	case "nacl", "js", "windows":
 		t.Skipf("skipping test on %s", runtime.GOOS)
@@ -355,10 +355,21 @@ func TestRemoveAllButReadOnly(t *testing.T) {
 		defer Chmod(d, 0777)
 	}
 
-	if err := RemoveAll(tempDir); err == nil {
+	err = RemoveAll(tempDir)
+	if err == nil {
 		t.Fatal("RemoveAll succeeded unexpectedly")
 	}
 
+	// The error should be of type *PathError.
+	// see issue 30491 for details.
+	if pathErr, ok := err.(*PathError); ok {
+		if g, w := pathErr.Path, filepath.Join(tempDir, "b", "y"); g != w {
+			t.Errorf("got %q, expected pathErr.path %q", g, w)
+		}
+	} else {
+		t.Errorf("got %T, expected *os.PathError", err)
+	}
+
 	for _, dir := range dirs {
 		_, err := Stat(filepath.Join(tempDir, dir))
 		if inReadonly(dir) {
@@ -372,3 +383,33 @@ func TestRemoveAllButReadOnly(t *testing.T) {
 		}
 	}
 }
+
+func TestRemoveUnreadableDir(t *testing.T) {
+	switch runtime.GOOS {
+	case "nacl", "js", "windows":
+		t.Skipf("skipping test on %s", runtime.GOOS)
+	}
+
+	if Getuid() == 0 {
+		t.Skip("skipping test when running as root")
+	}
+
+	t.Parallel()
+
+	tempDir, err := ioutil.TempDir("", "TestRemoveAllButReadOnly-")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer RemoveAll(tempDir)
+
+	target := filepath.Join(tempDir, "d0", "d1", "d2")
+	if err := MkdirAll(target, 0755); err != nil {
+		t.Fatal(err)
+	}
+	if err := Chmod(target, 0300); err != nil {
+		t.Fatal(err)
+	}
+	if err := RemoveAll(filepath.Join(tempDir, "d0")); err != nil {
+		t.Fatal(err)
+	}
+}

src/path/filepath/path.go

@@ -96,19 +96,14 @@ func Clean(path string) string {
 		}
 		return originalPath + "."
 	}
-
-	n := len(path)
-	if volLen > 2 && n == 1 && os.IsPathSeparator(path[0]) {
-		// UNC volume name with trailing slash.
-		return FromSlash(originalPath[:volLen])
-	}
 	rooted := os.IsPathSeparator(path[0])
 
 	// Invariants:
 	//	reading from path; r is index of next byte to process.
-	//	writing to out; w is index of next byte to write.
-	//	dotdot is index in out where .. must stop, either because
+	//	writing to buf; w is index of next byte to write.
+	//	dotdot is index in buf where .. must stop, either because
 	//		it is the leading slash or it is a leading ../../.. prefix.
+	n := len(path)
 	out := lazybuf{path: path, volAndPath: originalPath, volLen: volLen}
 	r, dotdot := 0, 0
 	if rooted {

src/path/filepath/path_test.go

@@ -93,9 +93,6 @@ var wincleantests = []PathTest{
 	{`//host/share/foo/../baz`, `\\host\share\baz`},
 	{`\\a\b\..\c`, `\\a\b\c`},
 	{`\\a\b`, `\\a\b`},
-	{`\\a\b\`, `\\a\b`},
-	{`\\folder\share\foo`, `\\folder\share\foo`},
-	{`\\folder\share\foo\`, `\\folder\share\foo`},
 }
 
 func TestClean(t *testing.T) {
@@ -1413,3 +1410,103 @@ func TestIssue29372(t *testing.T) {
 		}
 	}
 }
+
+// Issue 30520 part 1.
+func TestEvalSymlinksAboveRoot(t *testing.T) {
+	testenv.MustHaveSymlink(t)
+
+	t.Parallel()
+
+	tmpDir, err := ioutil.TempDir("", "TestEvalSymlinksAboveRoot")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(tmpDir)
+
+	evalTmpDir, err := filepath.EvalSymlinks(tmpDir)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := os.Mkdir(filepath.Join(evalTmpDir, "a"), 0777); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Symlink(filepath.Join(evalTmpDir, "a"), filepath.Join(evalTmpDir, "b")); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(filepath.Join(evalTmpDir, "a", "file"), nil, 0666); err != nil {
+		t.Fatal(err)
+	}
+
+	// Count the number of ".." elements to get to the root directory.
+	vol := filepath.VolumeName(evalTmpDir)
+	c := strings.Count(evalTmpDir[len(vol):], string(os.PathSeparator))
+	var dd []string
+	for i := 0; i < c+2; i++ {
+		dd = append(dd, "..")
+	}
+
+	wantSuffix := strings.Join([]string{"a", "file"}, string(os.PathSeparator))
+
+	// Try different numbers of "..".
+	for _, i := range []int{c, c + 1, c + 2} {
+		check := strings.Join([]string{evalTmpDir, strings.Join(dd[:i], string(os.PathSeparator)), evalTmpDir[len(vol)+1:], "b", "file"}, string(os.PathSeparator))
+		if resolved, err := filepath.EvalSymlinks(check); err != nil {
+			t.Errorf("EvalSymlinks(%q) failed: %v", check, err)
+		} else if !strings.HasSuffix(resolved, wantSuffix) {
+			t.Errorf("EvalSymlinks(%q) = %q does not end with %q", check, resolved, wantSuffix)
+		} else {
+			t.Logf("EvalSymlinks(%q) = %q", check, resolved)
+		}
+	}
+}
+
+// Issue 30520 part 2.
+func TestEvalSymlinksAboveRootChdir(t *testing.T) {
+	testenv.MustHaveSymlink(t)
+
+	tmpDir, err := ioutil.TempDir("", "TestEvalSymlinksAboveRootChdir")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(tmpDir)
+
+	wd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Chdir(wd)
+
+	if err := os.Chdir(tmpDir); err != nil {
+		t.Fatal(err)
+	}
+
+	subdir := filepath.Join("a", "b")
+	if err := os.MkdirAll(subdir, 0777); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Symlink(subdir, "c"); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(filepath.Join(subdir, "file"), nil, 0666); err != nil {
+		t.Fatal(err)
+	}
+
+	subdir = filepath.Join("d", "e", "f")
+	if err := os.MkdirAll(subdir, 0777); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Chdir(subdir); err != nil {
+		t.Fatal(err)
+	}
+
+	check := filepath.Join("..", "..", "..", "c", "file")
+	wantSuffix := filepath.Join("a", "b", "file")
+	if resolved, err := filepath.EvalSymlinks(check); err != nil {
+		t.Errorf("EvalSymlinks(%q) failed: %v", check, err)
+	} else if !strings.HasSuffix(resolved, wantSuffix) {
+		t.Errorf("EvalSymlinks(%q) = %q does not end with %q", check, resolved, wantSuffix)
+	} else {
+		t.Logf("EvalSymlinks(%q) = %q", check, resolved)
+	}
+}

src/path/filepath/symlink.go

@@ -44,18 +44,26 @@ func walkSymlinks(path string) (string, error) {
 		} else if path[start:end] == ".." {
 			// Back up to previous component if possible.
 			// Note that volLen includes any leading slash.
+
+			// Set r to the index of the last slash in dest,
+			// after the volume.
 			var r int
 			for r = len(dest) - 1; r >= volLen; r-- {
 				if os.IsPathSeparator(dest[r]) {
 					break
 				}
 			}
-			if r < volLen {
+			if r < volLen || dest[r+1:] == ".." {
+				// Either path has no slashes
+				// (it's empty or just "C:")
+				// or it ends in a ".." we had to keep.
+				// Either way, keep this "..".
 				if len(dest) > volLen {
 					dest += pathSeparator
 				}
 				dest += ".."
 			} else {
+				// Discard everything since the last slash.
 				dest = dest[:r]
 			}
 			continue

src/runtime/asm_wasm.s

@@ -443,7 +443,7 @@ TEXT runtime·gcWriteBarrier(SB), NOSPLIT, $16
 	// Record value
 	MOVD R1, 0(R5)
 	// Record *slot
-	MOVD R0, 8(R5)
+	MOVD (R0), 8(R5)
 
 	// Increment wbBuf.next
 	Get R5

src/runtime/crash_test.go

@@ -728,3 +728,15 @@ func TestG0StackOverflow(t *testing.T) {
 
 	runtime.G0StackOverflow()
 }
+
+// Test that panic message is not clobbered.
+// See issue 30150.
+func TestDoublePanic(t *testing.T) {
+	output := runTestProg(t, "testprog", "DoublePanic", "GODEBUG=clobberfree=1")
+	wants := []string{"panic: XXX", "panic: YYY"}
+	for _, want := range wants {
+		if !strings.Contains(output, want) {
+			t.Errorf("output:\n%s\n\nwant output containing: %s", output, want)
+		}
+	}
+}

src/runtime/extern.go

@@ -27,6 +27,10 @@ It is a comma-separated list of name=val pairs setting these named variables:
 	allocfreetrace: setting allocfreetrace=1 causes every allocation to be
 	profiled and a stack trace printed on each object's allocation and free.
 
+	clobberfree: setting clobberfree=1 causes the garbage collector to
+	clobber the memory content of an object with bad content when it frees
+	the object.
+
 	cgocheck: setting cgocheck=0 disables all checks for packages
 	using cgo to incorrectly pass Go pointers to non-Go code.
 	Setting cgocheck=1 (the default) enables relatively cheap
@@ -123,7 +127,7 @@ It is a comma-separated list of name=val pairs setting these named variables:
 	IDs will refer to the ID of the goroutine at the time of creation; it's possible for this
 	ID to be reused for another goroutine. Setting N to 0 will report no ancestry information.
 
-The net and net/http packages also refer to debugging variables in GODEBUG.
+The net, net/http, and crypto/tls packages also refer to debugging variables in GODEBUG.
 See the documentation for those packages for details.
 
 The GOMAXPROCS variable limits the number of operating system threads that

src/runtime/mgcmark.go

@@ -709,7 +709,20 @@ func scanstack(gp *g, gcw *gcWork) {
 		return true
 	}
 	gentraceback(^uintptr(0), ^uintptr(0), 0, gp, 0, nil, 0x7fffffff, scanframe, nil, 0)
+
+	// Find additional pointers that point into the stack from the heap.
+	// Currently this includes defers and panics. See also function copystack.
 	tracebackdefers(gp, scanframe, nil)
+	for d := gp._defer; d != nil; d = d.link {
+		// tracebackdefers above does not scan the func value, which could
+		// be a stack allocated closure. See issue 30453.
+		if d.fn != nil {
+			scanblock(uintptr(unsafe.Pointer(&d.fn)), sys.PtrSize, &oneptrmask[0], gcw, &state)
+		}
+	}
+	if gp._panic != nil {
+		state.putPtr(uintptr(unsafe.Pointer(gp._panic)))
+	}
 
 	// Find and scan all reachable stack objects.
 	state.buildIndex()

src/runtime/mgcsweep.go

@@ -291,7 +291,7 @@ func (s *mspan) sweep(preserve bool) bool {
 		}
 	}
 
-	if debug.allocfreetrace != 0 || raceenabled || msanenabled {
+	if debug.allocfreetrace != 0 || debug.clobberfree != 0 || raceenabled || msanenabled {
 		// Find all newly freed objects. This doesn't have to
 		// efficient; allocfreetrace has massive overhead.
 		mbits := s.markBitsForBase()
@@ -302,6 +302,9 @@ func (s *mspan) sweep(preserve bool) bool {
 				if debug.allocfreetrace != 0 {
 					tracefree(unsafe.Pointer(x), size)
 				}
+				if debug.clobberfree != 0 {
+					clobberfree(unsafe.Pointer(x), size)
+				}
 				if raceenabled {
 					racefree(unsafe.Pointer(x), size)
 				}
@@ -446,3 +449,12 @@ retry:
 		traceGCSweepDone()
 	}
 }
+
+// clobberfree sets the memory content at x to bad content, for debugging
+// purposes.
+func clobberfree(x unsafe.Pointer, size uintptr) {
+	// size (span.elemsize) is always a multiple of 4.
+	for i := uintptr(0); i < size; i += 4 {
+		*(*uint32)(add(x, i)) = 0xdeadbeef
+	}
+}

src/runtime/os_windows.go

@@ -29,6 +29,7 @@ const (
 //go:cgo_import_dynamic runtime._GetProcessAffinityMask GetProcessAffinityMask%3 "kernel32.dll"
 //go:cgo_import_dynamic runtime._GetQueuedCompletionStatus GetQueuedCompletionStatus%5 "kernel32.dll"
 //go:cgo_import_dynamic runtime._GetStdHandle GetStdHandle%1 "kernel32.dll"
+//go:cgo_import_dynamic runtime._GetSystemDirectoryA GetSystemDirectoryA%2 "kernel32.dll"
 //go:cgo_import_dynamic runtime._GetSystemInfo GetSystemInfo%1 "kernel32.dll"
 //go:cgo_import_dynamic runtime._GetThreadContext GetThreadContext%2 "kernel32.dll"
 //go:cgo_import_dynamic runtime._LoadLibraryW LoadLibraryW%1 "kernel32.dll"
@@ -47,12 +48,9 @@ const (
 //go:cgo_import_dynamic runtime._VirtualAlloc VirtualAlloc%4 "kernel32.dll"
 //go:cgo_import_dynamic runtime._VirtualFree VirtualFree%3 "kernel32.dll"
 //go:cgo_import_dynamic runtime._VirtualQuery VirtualQuery%3 "kernel32.dll"
-//go:cgo_import_dynamic runtime._WSAGetOverlappedResult WSAGetOverlappedResult%5 "ws2_32.dll"
 //go:cgo_import_dynamic runtime._WaitForSingleObject WaitForSingleObject%2 "kernel32.dll"
 //go:cgo_import_dynamic runtime._WriteConsoleW WriteConsoleW%5 "kernel32.dll"
 //go:cgo_import_dynamic runtime._WriteFile WriteFile%5 "kernel32.dll"
-//go:cgo_import_dynamic runtime._timeBeginPeriod timeBeginPeriod%1 "winmm.dll"
-//go:cgo_import_dynamic runtime._timeEndPeriod timeEndPeriod%1 "winmm.dll"
 
 type stdFunction unsafe.Pointer
 
@@ -75,6 +73,7 @@ var (
 	_GetProcessAffinityMask,
 	_GetQueuedCompletionStatus,
 	_GetStdHandle,
+	_GetSystemDirectoryA,
 	_GetSystemInfo,
 	_GetSystemTimeAsFileTime,
 	_GetThreadContext,
@@ -96,12 +95,9 @@ var (
 	_VirtualAlloc,
 	_VirtualFree,
 	_VirtualQuery,
-	_WSAGetOverlappedResult,
 	_WaitForSingleObject,
 	_WriteConsoleW,
 	_WriteFile,
-	_timeBeginPeriod,
-	_timeEndPeriod,
 	_ stdFunction
 
 	// Following syscalls are only available on some Windows PCs.
@@ -109,6 +105,7 @@ var (
 	_AddDllDirectory,
 	_AddVectoredContinueHandler,
 	_GetQueuedCompletionStatusEx,
+	_LoadLibraryExA,
 	_LoadLibraryExW,
 	_ stdFunction
 
@@ -126,6 +123,12 @@ var (
 	// links wrong printf function to cgo executable (see issue
 	// 12030 for details).
 	_NtWaitForSingleObject stdFunction
+
+	// These are from non-kernel32.dll, so we prefer to LoadLibraryEx them.
+	_timeBeginPeriod,
+	_timeEndPeriod,
+	_WSAGetOverlappedResult,
+	_ stdFunction
 )
 
 // Function to be called by windows CreateThread
@@ -173,6 +176,26 @@ func windowsFindfunc(lib uintptr, name []byte) stdFunction {
 	return stdFunction(unsafe.Pointer(f))
 }
 
+var sysDirectory [521]byte
+var sysDirectoryLen uintptr
+
+func windowsLoadSystemLib(name []byte) uintptr {
+	if useLoadLibraryEx {
+		return stdcall3(_LoadLibraryExA, uintptr(unsafe.Pointer(&name[0])), 0, _LOAD_LIBRARY_SEARCH_SYSTEM32)
+	} else {
+		if sysDirectoryLen == 0 {
+			l := stdcall2(_GetSystemDirectoryA, uintptr(unsafe.Pointer(&sysDirectory[0])), uintptr(len(sysDirectory)-1))
+			if l == 0 || l > uintptr(len(sysDirectory)-1) {
+				throw("Unable to determine system directory")
+			}
+			sysDirectory[l] = '\\'
+			sysDirectoryLen = l + 1
+		}
+		absName := append(sysDirectory[:sysDirectoryLen], name...)
+		return stdcall1(_LoadLibraryA, uintptr(unsafe.Pointer(&absName[0])))
+	}
+}
+
 func loadOptionalSyscalls() {
 	var kernel32dll = []byte("kernel32.dll\000")
 	k32 := stdcall1(_LoadLibraryA, uintptr(unsafe.Pointer(&kernel32dll[0])))
@@ -182,17 +205,19 @@ func loadOptionalSyscalls() {
 	_AddDllDirectory = windowsFindfunc(k32, []byte("AddDllDirectory\000"))
 	_AddVectoredContinueHandler = windowsFindfunc(k32, []byte("AddVectoredContinueHandler\000"))
 	_GetQueuedCompletionStatusEx = windowsFindfunc(k32, []byte("GetQueuedCompletionStatusEx\000"))
+	_LoadLibraryExA = windowsFindfunc(k32, []byte("LoadLibraryExA\000"))
 	_LoadLibraryExW = windowsFindfunc(k32, []byte("LoadLibraryExW\000"))
+	useLoadLibraryEx = (_LoadLibraryExW != nil && _LoadLibraryExA != nil && _AddDllDirectory != nil)
 
 	var advapi32dll = []byte("advapi32.dll\000")
-	a32 := stdcall1(_LoadLibraryA, uintptr(unsafe.Pointer(&advapi32dll[0])))
+	a32 := windowsLoadSystemLib(advapi32dll)
 	if a32 == 0 {
 		throw("advapi32.dll not found")
 	}
 	_RtlGenRandom = windowsFindfunc(a32, []byte("SystemFunction036\000"))
 
 	var ntdll = []byte("ntdll.dll\000")
-	n32 := stdcall1(_LoadLibraryA, uintptr(unsafe.Pointer(&ntdll[0])))
+	n32 := windowsLoadSystemLib(ntdll)
 	if n32 == 0 {
 		throw("ntdll.dll not found")
 	}
@@ -205,6 +230,27 @@ func loadOptionalSyscalls() {
 		}
 	}
 
+	var winmmdll = []byte("winmm.dll\000")
+	m32 := windowsLoadSystemLib(winmmdll)
+	if m32 == 0 {
+		throw("winmm.dll not found")
+	}
+	_timeBeginPeriod = windowsFindfunc(m32, []byte("timeBeginPeriod\000"))
+	_timeEndPeriod = windowsFindfunc(m32, []byte("timeEndPeriod\000"))
+	if _timeBeginPeriod == nil || _timeEndPeriod == nil {
+		throw("timeBegin/EndPeriod not found")
+	}
+
+	var ws232dll = []byte("ws2_32.dll\000")
+	ws232 := windowsLoadSystemLib(ws232dll)
+	if ws232 == 0 {
+		throw("ws2_32.dll not found")
+	}
+	_WSAGetOverlappedResult = windowsFindfunc(ws232, []byte("WSAGetOverlappedResult\000"))
+	if _WSAGetOverlappedResult == nil {
+		throw("WSAGetOverlappedResult not found")
+	}
+
 	if windowsFindfunc(n32, []byte("wine_get_version\000")) != nil {
 		// running on Wine
 		initWine(k32)
@@ -311,8 +357,6 @@ func osinit() {
 
 	loadOptionalSyscalls()
 
-	useLoadLibraryEx = (_LoadLibraryExW != nil && _AddDllDirectory != nil)
-
 	disableWER()
 
 	initExceptionHandler()

src/runtime/runtime-lldb_test.go

@@ -139,6 +139,7 @@ func TestLldbPython(t *testing.T) {
 	if final := os.Getenv("GOROOT_FINAL"); final != "" && runtime.GOROOT() != final {
 		t.Skip("gdb test can fail with GOROOT_FINAL pending")
 	}
+	testenv.SkipFlaky(t, 31188)
 
 	checkLldbPython(t)
 

src/runtime/runtime1.go

@@ -301,6 +301,7 @@ type dbgVar struct {
 var debug struct {
 	allocfreetrace     int32
 	cgocheck           int32
+	clobberfree        int32
 	efence             int32
 	gccheckmark        int32
 	gcpacertrace       int32
@@ -318,6 +319,7 @@ var debug struct {
 
 var dbgvars = []dbgVar{
 	{"allocfreetrace", &debug.allocfreetrace},
+	{"clobberfree", &debug.clobberfree},
 	{"cgocheck", &debug.cgocheck},
 	{"efence", &debug.efence},
 	{"gccheckmark", &debug.gccheckmark},

src/runtime/stack_test.go

@@ -787,3 +787,11 @@ func TestTracebackAncestors(t *testing.T) {
 		}
 	}
 }
+
+// Test that defer closure is correctly scanned when the stack is scanned.
+func TestDeferLiveness(t *testing.T) {
+	output := runTestProg(t, "testprog", "DeferLiveness", "GODEBUG=clobberfree=1")
+	if output != "" {
+		t.Errorf("output:\n%s\n\nwant no output", output)
+	}
+}

src/runtime/syscall_windows.go

@@ -104,9 +104,13 @@ func compileCallback(fn eface, cleanstack bool) (code uintptr) {
 
 const _LOAD_LIBRARY_SEARCH_SYSTEM32 = 0x00000800
 
+// When available, this function will use LoadLibraryEx with the filename
+// parameter and the important SEARCH_SYSTEM32 argument. But on systems that
+// do not have that option, absoluteFilepath should contain a fallback
+// to the full path inside of system32 for use with vanilla LoadLibrary.
 //go:linkname syscall_loadsystemlibrary syscall.loadsystemlibrary
 //go:nosplit
-func syscall_loadsystemlibrary(filename *uint16) (handle, err uintptr) {
+func syscall_loadsystemlibrary(filename *uint16, absoluteFilepath *uint16) (handle, err uintptr) {
 	lockOSThread()
 	defer unlockOSThread()
 	c := &getg().m.syscall
@@ -121,15 +125,9 @@ func syscall_loadsystemlibrary(filename *uint16) (handle, err uintptr) {
 		}{filename, 0, _LOAD_LIBRARY_SEARCH_SYSTEM32}
 		c.args = uintptr(noescape(unsafe.Pointer(&args)))
 	} else {
-		// User doesn't have KB2533623 installed. The caller
-		// wanted to only load the filename DLL from the
-		// System32 directory but that facility doesn't exist,
-		// so just load it the normal way. This is a potential
-		// security risk, but so is not installing security
-		// updates.
 		c.fn = getLoadLibrary()
 		c.n = 1
-		c.args = uintptr(noescape(unsafe.Pointer(&filename)))
+		c.args = uintptr(noescape(unsafe.Pointer(&absoluteFilepath)))
 	}
 
 	cgocall(asmstdcallAddr, unsafe.Pointer(c))

src/runtime/testdata/testprog/crash.go

@@ -11,6 +11,7 @@ import (
 
 func init() {
 	register("Crash", Crash)
+	register("DoublePanic", DoublePanic)
 }
 
 func test(name string) {
@@ -43,3 +44,23 @@ func Crash() {
 	testInNewThread("second-new-thread")
 	test("main-again")
 }
+
+type P string
+
+func (p P) String() string {
+	// Try to free the "YYY" string header when the "XXX"
+	// panic is stringified.
+	runtime.GC()
+	runtime.GC()
+	runtime.GC()
+	return string(p)
+}
+
+// Test that panic message is not clobbered.
+// See issue 30150.
+func DoublePanic() {
+	defer func() {
+		panic(P("YYY"))
+	}()
+	panic(P("XXX"))
+}

src/runtime/testdata/testprog/gc.go

@@ -18,6 +18,7 @@ func init() {
 	register("GCFairness2", GCFairness2)
 	register("GCSys", GCSys)
 	register("GCPhys", GCPhys)
+	register("DeferLiveness", DeferLiveness)
 }
 
 func GCSys() {
@@ -207,3 +208,25 @@ func GCPhys() {
 	fmt.Println("OK")
 	runtime.KeepAlive(saved)
 }
+
+// Test that defer closure is correctly scanned when the stack is scanned.
+func DeferLiveness() {
+	var x [10]int
+	escape(&x)
+	fn := func() {
+		if x[0] != 42 {
+			panic("FAIL")
+		}
+	}
+	defer fn()
+
+	x[0] = 42
+	runtime.GC()
+	runtime.GC()
+	runtime.GC()
+}
+
+//go:noinline
+func escape(x interface{}) { sink2 = x; sink2 = nil }
+
+var sink2 interface{}

src/syscall/dll_windows.go

@@ -28,7 +28,7 @@ func Syscall12(trap, nargs, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12 ui
 func Syscall15(trap, nargs, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15 uintptr) (r1, r2 uintptr, err Errno)
 func Syscall18(trap, nargs, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17, a18 uintptr) (r1, r2 uintptr, err Errno)
 func loadlibrary(filename *uint16) (handle uintptr, err Errno)
-func loadsystemlibrary(filename *uint16) (handle uintptr, err Errno)
+func loadsystemlibrary(filename *uint16, absoluteFilepath *uint16) (handle uintptr, err Errno)
 func getprocaddress(handle uintptr, procname *uint8) (proc uintptr, err Errno)
 
 // A DLL implements access to a single DLL.
@@ -37,6 +37,26 @@ type DLL struct {
 	Handle Handle
 }
 
+// We use this for computing the absolute path for system DLLs on systems
+// where SEARCH_SYSTEM32 is not available.
+var systemDirectoryPrefix string
+
+func init() {
+	n := uint32(MAX_PATH)
+	for {
+		b := make([]uint16, n)
+		l, e := getSystemDirectory(&b[0], n)
+		if e != nil {
+			panic("Unable to determine system directory: " + e.Error())
+		}
+		if l <= n {
+			systemDirectoryPrefix = UTF16ToString(b[:l]) + "\\"
+			break
+		}
+		n = l
+	}
+}
+
 // LoadDLL loads the named DLL file into memory.
 //
 // If name is not an absolute path and is not a known system DLL used by
@@ -53,7 +73,11 @@ func LoadDLL(name string) (*DLL, error) {
 	var h uintptr
 	var e Errno
 	if sysdll.IsSystemDLL[name] {
-		h, e = loadsystemlibrary(namep)
+		absoluteFilepathp, err := UTF16PtrFromString(systemDirectoryPrefix + name)
+		if err != nil {
+			return nil, err
+		}
+		h, e = loadsystemlibrary(namep, absoluteFilepathp)
 	} else {
 		h, e = loadlibrary(namep)
 	}

src/syscall/security_windows.go

@@ -290,6 +290,7 @@ type Tokenprimarygroup struct {
 //sys	OpenProcessToken(h Handle, access uint32, token *Token) (err error) = advapi32.OpenProcessToken
 //sys	GetTokenInformation(t Token, infoClass uint32, info *byte, infoLen uint32, returnedLen *uint32) (err error) = advapi32.GetTokenInformation
 //sys	GetUserProfileDirectory(t Token, dir *uint16, dirLen *uint32) (err error) = userenv.GetUserProfileDirectoryW
+//sys	getSystemDirectory(dir *uint16, dirLen uint32) (len uint32, err error) = kernel32.GetSystemDirectoryW
 
 // An access token contains the security information for a logon session.
 // The system creates an access token when a user logs on, and every

src/syscall/syscall_linux_test.go

@@ -360,10 +360,23 @@ func TestSyscallNoError(t *testing.T) {
 		strconv.FormatUint(uint64(-uid), 10) + " / " +
 		strconv.FormatUint(uint64(uid), 10)
 	if got != want {
+		if filesystemIsNoSUID(tmpBinary) {
+			t.Skip("skipping test when temp dir is mounted nosuid")
+		}
 		t.Errorf("expected %s, got %s", want, got)
 	}
 }
 
+// filesystemIsNoSUID reports whether the filesystem for the given
+// path is mounted nosuid.
+func filesystemIsNoSUID(path string) bool {
+	var st syscall.Statfs_t
+	if syscall.Statfs(path, &st) != nil {
+		return false
+	}
+	return st.Flags&syscall.MS_NOSUID != 0
+}
+
 func syscallNoError() {
 	// Test that the return value from SYS_GETEUID32 (which cannot fail)
 	// doesn't get treated as an error (see https://golang.org/issue/22924)

src/syscall/zsyscall_windows.go

@@ -190,6 +190,7 @@ var (
 	procOpenProcessToken                   = modadvapi32.NewProc("OpenProcessToken")
 	procGetTokenInformation                = modadvapi32.NewProc("GetTokenInformation")
 	procGetUserProfileDirectoryW           = moduserenv.NewProc("GetUserProfileDirectoryW")
+	procGetSystemDirectoryW                = modkernel32.NewProc("GetSystemDirectoryW")
 )
 
 func GetLastError() (lasterr error) {
@@ -1916,3 +1917,16 @@ func GetUserProfileDirectory(t Token, dir *uint16, dirLen *uint32) (err error) {
 	}
 	return
 }
+
+func getSystemDirectory(dir *uint16, dirLen uint32) (len uint32, err error) {
+	r0, _, e1 := Syscall(procGetSystemDirectoryW.Addr(), 2, uintptr(unsafe.Pointer(dir)), uintptr(dirLen), 0)
+	len = uint32(r0)
+	if len == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = EINVAL
+		}
+	}
+	return
+}

src/text/template/exec.go

@@ -576,6 +576,13 @@ func (s *state) evalField(dot reflect.Value, fieldName string, node parse.Node,
 	}
 	typ := receiver.Type()
 	receiver, isNil := indirect(receiver)
+	if receiver.Kind() == reflect.Interface && isNil {
+		// Calling a method on a nil interface can't work. The
+		// MethodByName method call below would panic.
+		s.errorf("nil pointer evaluating %s.%s", typ, fieldName)
+		return zero
+	}
+
 	// Unless it's an interface, need to get to a value of type *T to guarantee
 	// we see all methods of T and *T.
 	ptr := receiver

src/text/template/exec_test.go

@@ -58,8 +58,10 @@ type T struct {
 	Empty3 interface{}
 	Empty4 interface{}
 	// Non-empty interfaces.
-	NonEmptyInterface    I
-	NonEmptyInterfacePtS *I
+	NonEmptyInterface         I
+	NonEmptyInterfacePtS      *I
+	NonEmptyInterfaceNil      I
+	NonEmptyInterfaceTypedNil I
 	// Stringer.
 	Str fmt.Stringer
 	Err error
@@ -141,24 +143,25 @@ var tVal = &T{
 		{"one": 1, "two": 2},
 		{"eleven": 11, "twelve": 12},
 	},
-	Empty1:               3,
-	Empty2:               "empty2",
-	Empty3:               []int{7, 8},
-	Empty4:               &U{"UinEmpty"},
-	NonEmptyInterface:    &T{X: "x"},
-	NonEmptyInterfacePtS: &siVal,
-	Str:                  bytes.NewBuffer([]byte("foozle")),
-	Err:                  errors.New("erroozle"),
-	PI:                   newInt(23),
-	PS:                   newString("a string"),
-	PSI:                  newIntSlice(21, 22, 23),
-	BinaryFunc:           func(a, b string) string { return fmt.Sprintf("[%s=%s]", a, b) },
-	VariadicFunc:         func(s ...string) string { return fmt.Sprint("<", strings.Join(s, "+"), ">") },
-	VariadicFuncInt:      func(a int, s ...string) string { return fmt.Sprint(a, "=<", strings.Join(s, "+"), ">") },
-	NilOKFunc:            func(s *int) bool { return s == nil },
-	ErrFunc:              func() (string, error) { return "bla", nil },
-	PanicFunc:            func() string { panic("test panic") },
-	Tmpl:                 Must(New("x").Parse("test template")), // "x" is the value of .X
+	Empty1:                    3,
+	Empty2:                    "empty2",
+	Empty3:                    []int{7, 8},
+	Empty4:                    &U{"UinEmpty"},
+	NonEmptyInterface:         &T{X: "x"},
+	NonEmptyInterfacePtS:      &siVal,
+	NonEmptyInterfaceTypedNil: (*T)(nil),
+	Str:                       bytes.NewBuffer([]byte("foozle")),
+	Err:                       errors.New("erroozle"),
+	PI:                        newInt(23),
+	PS:                        newString("a string"),
+	PSI:                       newIntSlice(21, 22, 23),
+	BinaryFunc:                func(a, b string) string { return fmt.Sprintf("[%s=%s]", a, b) },
+	VariadicFunc:              func(s ...string) string { return fmt.Sprint("<", strings.Join(s, "+"), ">") },
+	VariadicFuncInt:           func(a int, s ...string) string { return fmt.Sprint(a, "=<", strings.Join(s, "+"), ">") },
+	NilOKFunc:                 func(s *int) bool { return s == nil },
+	ErrFunc:                   func() (string, error) { return "bla", nil },
+	PanicFunc:                 func() string { panic("test panic") },
+	Tmpl:                      Must(New("x").Parse("test template")), // "x" is the value of .X
 }
 
 var tSliceOfNil = []*T{nil}
@@ -365,6 +368,7 @@ var execTests = []execTest{
 	{".NilOKFunc not nil", "{{call .NilOKFunc .PI}}", "false", tVal, true},
 	{".NilOKFunc nil", "{{call .NilOKFunc nil}}", "true", tVal, true},
 	{"method on nil value from slice", "-{{range .}}{{.Method1 1234}}{{end}}-", "-1234-", tSliceOfNil, true},
+	{"method on typed nil interface value", "{{.NonEmptyInterfaceTypedNil.Method0}}", "M0", tVal, true},
 
 	// Function call builtin.
 	{".BinaryFunc", "{{call .BinaryFunc `1` `2`}}", "[1=2]", tVal, true},
@@ -1492,6 +1496,11 @@ func TestExecutePanicDuringCall(t *testing.T) {
 			"{{call .PanicFunc}}", tVal,
 			`template: t:1:2: executing "t" at <call .PanicFunc>: error calling call: test panic`,
 		},
+		{
+			"method call on nil interface",
+			"{{.NonEmptyInterfaceNil.Method0}}", tVal,
+			`template: t:1:23: executing "t" at <.NonEmptyInterfaceNil.Method0>: nil pointer evaluating template.I.Method0`,
+		},
 	}
 	for _, tc := range tests {
 		b := new(bytes.Buffer)

test/checkbce.go

@@ -33,9 +33,7 @@ func f1(a [256]int, i int) {
 
 	if 4 <= i && i < len(a) {
 		useInt(a[i])
-		useInt(a[i-1]) // ERROR "Found IsInBounds$"
-		// TODO: 'if 4 <= i && i < len(a)' gets rewritten to 'if uint(i - 4) < 256 - 4',
-		// which the bounds checker cannot yet use to infer that the next line doesn't need a bounds check.
+		useInt(a[i-1])
 		useInt(a[i-4])
 	}
 }

test/escape_because.go

@@ -43,7 +43,7 @@ func f2(q *int) { // ERROR "from &u \(address-of\) at escape_because.go:43$" "fr
 	sink = &u // ERROR "&u escapes to heap$" "from &u \(interface-converted\) at escape_because.go:43$" "from sink \(assigned to top level variable\) at escape_because.go:43$"
 }
 
-func f3(r *int) interface{} { // ERROR "from \[\]\*int literal \(slice-literal-element\) at escape_because.go:47$" "from c \(assigned\) at escape_because.go:47$" "from c \(interface-converted\) at escape_because.go:48$" "from ~r1 \(return\) at escape_because.go:48$" "leaking param: r to result ~r1 level=-1$"
+func f3(r *int) interface{} { // ERROR "from \[\]\*int literal \(slice-literal-element\) at escape_because.go:47$" "from c \(assigned\) at escape_because.go:47$" "from c \(interface-converted\) at escape_because.go:48$" "from ~r1 \(return\) at escape_because.go:48$" "leaking param: r"
 	c := []*int{r} // ERROR "\[\]\*int literal escapes to heap$" "from c \(assigned\) at escape_because.go:47$" "from c \(interface-converted\) at escape_because.go:48$" "from ~r1 \(return\) at escape_because.go:48$"
 	return c       // "return" // ERROR "c escapes to heap$" "from ~r1 \(return\) at escape_because.go:48$"
 }

test/escape_param.go

@@ -424,3 +424,18 @@ func h(x *Node) { // ERROR "leaking param: x"
 	Sink = g(y)
 	f(y)
 }
+
+// interface(in) -> out
+// See also issue 29353.
+
+// Convert to a non-direct interface, require an allocation and
+// copy x to heap (not to result).
+func param14a(x [4]*int) interface{} { // ERROR "leaking param: x$"
+	return x // ERROR "x escapes to heap"
+}
+
+// Convert to a direct interface, does not need an allocation.
+// So x only leaks to result.
+func param14b(x *int) interface{} { // ERROR "leaking param: x to result ~r1 level=0"
+	return x // ERROR "x escapes to heap"
+}

test/fixedbugs/issue29215.go

@@ -16,3 +16,20 @@ func f() {
         }
         _ = s == "bbb"
 }
+
+// Another case: load from negative offset of a symbol
+// in dead code (issue 30257).
+func g() {
+	var i int
+	var s string
+
+	if true {
+		s = "a"
+	}
+
+	if f := 0.0; -f < 0 {
+		i = len(s[:4])
+	}
+
+	_ = s[i-1:0] != "bb" && true
+}

test/fixedbugs/issue30476.go

@@ -0,0 +1,30 @@
+// run
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 30476: KeepAlive didn't keep stack object alive.
+
+package main
+
+import "runtime"
+
+func main() {
+	x := new([10]int)
+	runtime.SetFinalizer(x, func(*[10]int) { panic("FAIL: finalizer runs") })
+	p := &T{x, 0}
+	use(p)
+	runtime.GC()
+	runtime.GC()
+	runtime.GC()
+	runtime.KeepAlive(p)
+}
+
+type T struct {
+	x *[10]int
+	y int
+}
+
+//go:noinline
+func use(*T) {}

test/fixedbugs/issue30566a.go

@@ -0,0 +1,23 @@
+// run
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "fmt"
+
+//go:noinline
+func ident(s string) string { return s }
+
+func returnSecond(x bool, s string) string { return s }
+
+func identWrapper(s string) string { return ident(s) }
+
+func main() {
+	got := returnSecond((false || identWrapper("bad") != ""), ident("good"))
+	if got != "good" {
+		panic(fmt.Sprintf("wanted \"good\", got \"%s\"", got))
+	}
+}

test/fixedbugs/issue30566b.go

@@ -0,0 +1,27 @@
+// run
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+)
+
+func main() {
+	_, _ = false || g(1), g(2)
+	if !bytes.Equal(x, []byte{1, 2}) {
+		panic(fmt.Sprintf("wanted [1,2], got %v", x))
+	}
+}
+
+var x []byte
+
+//go:noinline
+func g(b byte) bool {
+	x = append(x, b)
+	return false
+}

test/fixedbugs/issue30956.go

@@ -0,0 +1,32 @@
+// run
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Check for compile generated static data for literal
+// composite struct
+
+package main
+
+import "fmt"
+
+type X struct {
+	V interface{}
+
+	a int
+	b int
+	c int
+}
+
+func pr(x X) {
+	fmt.Println(x.V)
+}
+
+func main() {
+	pr(X{
+		V: struct {
+			A int
+		}{42},
+	})
+}

test/fixedbugs/issue30956.out

@@ -0,0 +1 @@
+{42}

test/fixedbugs/issue30977.go

@@ -0,0 +1,52 @@
+// run
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 30977: write barrier call clobbers volatile
+// value when there are multiple uses of the value.
+
+package main
+
+import "runtime"
+
+type T struct {
+	a, b, c, d, e string
+}
+
+//go:noinline
+func g() T {
+	return T{"a", "b", "c", "d", "e"}
+}
+
+//go:noinline
+func f() {
+	// The compiler optimizes this to direct copying
+	// the call result to both globals, with write
+	// barriers. The first write barrier call clobbers
+	// the result of g on stack.
+	X = g()
+	Y = X
+}
+
+var X, Y T
+
+const N = 1000
+
+func main() {
+	// Keep GC running so the write barrier is on.
+	go func() {
+		for {
+			runtime.GC()
+		}
+	}()
+
+	for i := 0; i < N; i++ {
+		runtime.Gosched()
+		f()
+		if X != Y {
+			panic("FAIL")
+		}
+	}
+}

test/live.go

@@ -572,7 +572,7 @@ func f36() {
 func f37() {
 	if (m33[byteptr()] == 0 || // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
 		m33[byteptr()] == 0) && // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
-		m33[byteptr()] == 0 { // ERROR "stack object .autotmp_[0-9]+ interface \{\}"
+		m33[byteptr()] == 0 {
 		printnl()
 		return
 	}
@@ -697,9 +697,10 @@ func f41(p, q *int) (r *int) { // ERROR "live at entry to f41: p q$"
 
 func f42() {
 	var p, q, r int
-	f43([]*int{&p,&q,&r}) // ERROR "stack object .autotmp_[0-9]+ \[3\]\*int$"
-	f43([]*int{&p,&r,&q})
-	f43([]*int{&q,&p,&r})
+	f43([]*int{&p, &q, &r}) // ERROR "stack object .autotmp_[0-9]+ \[3\]\*int$"
+	f43([]*int{&p, &r, &q})
+	f43([]*int{&q, &p, &r})
 }
+
 //go:noescape
 func f43(a []*int)