[release-branch.go1.12] cmd/vendor/golang.org/x/tools/go/analysis: update from release-branch.go1.12

$ ./update-xtools.sh
Copied /Users/rsc/src/golang.org/x/tools@aa829657 to .
$ cd ~/src/golang.org/x/tools
$ git log -n1 aa829657
commit aa82965741a9fecd12b026fbb3d3c6ed3231b8f8 (HEAD -> release-branch.go1.12, origin/release-branch.go1.12)
Author:     Daniel Martí <mvdan@mvdan.cc>
AuthorDate: Fri Mar 1 11:00:19 2019 +0000
Commit:     Brad Fitzpatrick <bradfitz@golang.org>
CommitDate: Wed Mar 13 21:06:03 2019 +0000
...
$

Picks up cmd/vet fixes that have been inadvertently missed in point releases so far.

Fixes #30399.
Fixes #30465.

Change-Id: Ibcfaac51d134205b986b32f857d54006b19c896a
Reviewed-on: https://go-review.googlesource.com/c/go/+/174519
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

12 files changed, 49 insertions, 54 deletions

diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/analysis.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/analysis.go
index 21baa02a8d..4d8a6e5e7d 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/analysis.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/analysis.go
@@ -87,6 +87,7 @@ type Pass struct {
 	OtherFiles []string       // names of non-Go files of this package
 	Pkg        *types.Package // type information about the package
 	TypesInfo  *types.Info    // type information about the syntax trees
+	TypesSizes types.Sizes    // function for computing sizes of types
 
 	// Report reports a Diagnostic, a finding about a specific location
 	// in the analyzed source code such as a potential mistake.
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/doc.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/doc.go
index f925849ab5..2d44b0458a 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/doc.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/doc.go
@@ -246,7 +246,7 @@ An Analyzer that uses facts must declare their types:
 
 	var Analyzer = &analysis.Analyzer{
 		Name:       "printf",
-		FactTypes: []reflect.Type{reflect.TypeOf(new(isWrapper))},
+		FactTypes: []analysis.Fact{new(isWrapper)},
 		...
 	}
 
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go
index dce1ef7bd5..6403d7783a 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go
@@ -114,7 +114,8 @@ func init() {
 			// library we cannot assume types.SizesFor is consistent with arches.
 			// For now, assume 64-bit norms and print a warning.
 			// But this warning should really be deferred until we attempt to use
-			// arch, which is very unlikely.
+			// arch, which is very unlikely. Better would be
+			// to defer size computation until we have Pass.TypesSizes.
 			arch.sizes = types.SizesFor("gc", "amd64")
 			log.Printf("unknown architecture %s", arch.name)
 		}
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/cgocall/cgocall.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/cgocall/cgocall.go
index 993f1ce3c4..1e4fac8595 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/cgocall/cgocall.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/cgocall/cgocall.go
@@ -9,7 +9,6 @@ package cgocall
 import (
 	"fmt"
 	"go/ast"
-	"go/build"
 	"go/format"
 	"go/parser"
 	"go/token"
@@ -45,7 +44,7 @@ func run(pass *analysis.Pass) (interface{}, error) {
 		return nil, nil // doesn't use cgo
 	}
 
-	cgofiles, info, err := typeCheckCgoSourceFiles(pass.Fset, pass.Pkg, pass.Files, pass.TypesInfo)
+	cgofiles, info, err := typeCheckCgoSourceFiles(pass.Fset, pass.Pkg, pass.Files, pass.TypesInfo, pass.TypesSizes)
 	if err != nil {
 		return nil, err
 	}
@@ -171,7 +170,7 @@ func checkCgo(fset *token.FileSet, f *ast.File, info *types.Info, reportf func(t
 // limited ourselves here to preserving function bodies and initializer
 // expressions since that is all that the cgocall analyzer needs.
 //
-func typeCheckCgoSourceFiles(fset *token.FileSet, pkg *types.Package, files []*ast.File, info *types.Info) ([]*ast.File, *types.Info, error) {
+func typeCheckCgoSourceFiles(fset *token.FileSet, pkg *types.Package, files []*ast.File, info *types.Info, sizes types.Sizes) ([]*ast.File, *types.Info, error) {
 	const thispkg = "·this·"
 
 	// Which files are cgo files?
@@ -269,8 +268,7 @@ func typeCheckCgoSourceFiles(fset *token.FileSet, pkg *types.Package, files []*a
 		Importer: importerFunc(func(path string) (*types.Package, error) {
 			return importMap[path], nil
 		}),
-		// TODO(adonovan): Sizes should probably be provided by analysis.Pass.
-		Sizes: types.SizesFor("gc", build.Default.GOARCH),
+		Sizes: sizes,
 		Error: func(error) {}, // ignore errors (e.g. unused import)
 	}
 
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/composite/composite.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/composite/composite.go
index 9cca7781d0..2abe7c6d51 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/composite/composite.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/composite/composite.go
@@ -21,7 +21,16 @@ const Doc = `check for unkeyed composite literals
 This analyzer reports a diagnostic for composite literals of struct
 types imported from another package that do not use the field-keyed
 syntax. Such literals are fragile because the addition of a new field
-(even if unexported) to the struct will cause compilation to fail.`
+(even if unexported) to the struct will cause compilation to fail.
+
+As an example,
+
+	err = &net.DNSConfigError{err}
+
+should be replaced by:
+
+	err = &net.DNSConfigError{Err: err}
+`
 
 var Analyzer = &analysis.Analyzer{
 	Name:             "composites",
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/inspect/inspect.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/inspect/inspect.go
index bd06549984..8213f63313 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/inspect/inspect.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/inspect/inspect.go
@@ -8,7 +8,11 @@
 //
 // Example of use in another analysis:
 //
-//	import "golang.org/x/tools/go/analysis/passes/inspect"
+//	import (
+//		"golang.org/x/tools/go/analysis"
+//		"golang.org/x/tools/go/analysis/passes/inspect"
+//		"golang.org/x/tools/go/ast/inspector"
+//	)
 //
 //	var Analyzer = &analysis.Analyzer{
 //		...
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go
index c0265aafee..b73ff5e0c3 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go
@@ -453,15 +453,23 @@ func printfNameAndKind(pass *analysis.Pass, call *ast.CallExpr) (fn *types.Func,
 }
 
 // isFormatter reports whether t satisfies fmt.Formatter.
-// Unlike fmt.Stringer, it's impossible to satisfy fmt.Formatter without importing fmt.
-func isFormatter(pass *analysis.Pass, t types.Type) bool {
-	for _, imp := range pass.Pkg.Imports() {
-		if imp.Path() == "fmt" {
-			formatter := imp.Scope().Lookup("Formatter").Type().Underlying().(*types.Interface)
-			return types.Implements(t, formatter)
-		}
+// The only interface method to look for is "Format(State, rune)".
+func isFormatter(typ types.Type) bool {
+	obj, _, _ := types.LookupFieldOrMethod(typ, false, nil, "Format")
+	fn, ok := obj.(*types.Func)
+	if !ok {
+		return false
 	}
-	return false
+	sig := fn.Type().(*types.Signature)
+	return sig.Params().Len() == 2 &&
+		sig.Results().Len() == 0 &&
+		isNamed(sig.Params().At(0).Type(), "fmt", "State") &&
+		types.Identical(sig.Params().At(1).Type(), types.Typ[types.Rune])
+}
+
+func isNamed(T types.Type, pkgpath, name string) bool {
+	named, ok := T.(*types.Named)
+	return ok && named.Obj().Pkg().Path() == pkgpath && named.Obj().Name() == name
 }
 
 // formatState holds the parsed representation of a printf directive such as "%3.*[4]d".
@@ -753,7 +761,7 @@ func okPrintfArg(pass *analysis.Pass, call *ast.CallExpr, state *formatState) (o
 	formatter := false
 	if state.argNum < len(call.Args) {
 		if tv, ok := pass.TypesInfo.Types[call.Args[state.argNum]]; ok {
-			formatter = isFormatter(pass, tv.Type)
+			formatter = isFormatter(tv.Type)
 		}
 	}
 
@@ -831,7 +839,7 @@ func recursiveStringer(pass *analysis.Pass, e ast.Expr) bool {
 	typ := pass.TypesInfo.Types[e].Type
 
 	// It's unlikely to be a recursive stringer if it has a Format method.
-	if isFormatter(pass, typ) {
+	if isFormatter(typ) {
 		return false
 	}
 
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/types.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/types.go
index e8810464cd..12286fd5df 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/types.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/types.go
@@ -2,7 +2,6 @@ package printf
 
 import (
 	"go/ast"
-	"go/build"
 	"go/types"
 
 	"golang.org/x/tools/go/analysis"
@@ -39,7 +38,7 @@ func matchArgTypeInternal(pass *analysis.Pass, t printfArgType, typ types.Type,
 		}
 	}
 	// If the type implements fmt.Formatter, we have nothing to check.
-	if isFormatter(pass, typ) {
+	if isFormatter(typ) {
 		return true
 	}
 	// If we can use a string, might arg (dynamically) implement the Stringer or Error interface?
@@ -235,5 +234,3 @@ func matchStructArgType(pass *analysis.Pass, t printfArgType, typ *types.Struct,
 	}
 	return true
 }
-
-var archSizes = types.SizesFor("gc", build.Default.GOARCH)
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/shift/shift.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/shift/shift.go
index 56b150b2b1..39f54573c9 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/shift/shift.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/shift/shift.go
@@ -12,10 +12,8 @@ package shift
 
 import (
 	"go/ast"
-	"go/build"
 	"go/constant"
 	"go/token"
-	"go/types"
 
 	"golang.org/x/tools/go/analysis"
 	"golang.org/x/tools/go/analysis/passes/inspect"
@@ -93,36 +91,9 @@ func checkLongShift(pass *analysis.Pass, node ast.Node, x, y ast.Expr) {
 	if t == nil {
 		return
 	}
-	b, ok := t.Underlying().(*types.Basic)
-	if !ok {
-		return
-	}
-	var size int64
-	switch b.Kind() {
-	case types.Uint8, types.Int8:
-		size = 8
-	case types.Uint16, types.Int16:
-		size = 16
-	case types.Uint32, types.Int32:
-		size = 32
-	case types.Uint64, types.Int64:
-		size = 64
-	case types.Int, types.Uint:
-		size = uintBitSize
-	case types.Uintptr:
-		size = uintptrBitSize
-	default:
-		return
-	}
+	size := 8 * pass.TypesSizes.Sizeof(t)
 	if amt >= size {
 		ident := analysisutil.Format(pass.Fset, x)
 		pass.Reportf(node.Pos(), "%s (%d bits) too small for shift of %d", ident, size, amt)
 	}
 }
-
-var (
-	uintBitSize    = 8 * archSizes.Sizeof(types.Typ[types.Uint])
-	uintptrBitSize = 8 * archSizes.Sizeof(types.Typ[types.Uintptr])
-)
-
-var archSizes = types.SizesFor("gc", build.Default.GOARCH)
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/structtag/structtag.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/structtag/structtag.go
index 2b67c376ba..5b27208e91 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/structtag/structtag.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/passes/structtag/structtag.go
@@ -96,6 +96,11 @@ func checkTagDuplicates(pass *analysis.Pass, tag, key string, nearest, field *ty
 	}
 	if val == "" || val[0] == ',' {
 		if field.Anonymous() {
+			// Disable this check enhancement in Go 1.12.1; some
+			// false positives were spotted in the initial 1.12
+			// release. See https://golang.org/issues/30465.
+			return
+
 			typ, ok := field.Type().Underlying().(*types.Struct)
 			if !ok {
 				return
diff --git a/src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go b/src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go
index 76dabc28b9..ba2e66fed2 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/analysis/unitchecker/unitchecker.go
@@ -329,6 +329,7 @@ func run(fset *token.FileSet, cfg *Config, analyzers []*analysis.Analyzer) ([]re
 				OtherFiles:        cfg.NonGoFiles,
 				Pkg:               pkg,
 				TypesInfo:         info,
+				TypesSizes:        tc.Sizes,
 				ResultOf:          inputs,
 				Report:            func(d analysis.Diagnostic) { act.diagnostics = append(act.diagnostics, d) },
 				ImportObjectFact:  facts.ImportObjectFact,
diff --git a/src/cmd/vendor/golang.org/x/tools/go/ast/inspector/inspector.go b/src/cmd/vendor/golang.org/x/tools/go/ast/inspector/inspector.go
index db88a95109..ddbdd3f08f 100644
--- a/src/cmd/vendor/golang.org/x/tools/go/ast/inspector/inspector.go
+++ b/src/cmd/vendor/golang.org/x/tools/go/ast/inspector/inspector.go
@@ -14,7 +14,7 @@
 // Experiments suggest the inspector's traversals are about 2.5x faster
 // than ast.Inspect, but it may take around 5 traversals for this
 // benefit to amortize the inspector's construction cost.
-// If efficiency is the primary concern, do not use use Inspector for
+// If efficiency is the primary concern, do not use Inspector for
 // one-off traversals.
 package inspector