diff --git a/README.md b/README.md
index e5affe4..0b78a52 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,8 @@
 
 ## Installation
 
+Golint requires Go 1.5 or later.
+
     go get -u github.com/golang/lint/golint
 
 ## Usage
diff --git a/lint.go b/lint.go
index 060ea5c..52750b9 100644
--- a/lint.go
+++ b/lint.go
@@ -14,6 +14,7 @@
 	"go/parser"
 	"go/printer"
 	"go/token"
+	"go/types"
 	"regexp"
 	"sort"
 	"strconv"
@@ -21,8 +22,7 @@
 	"unicode"
 	"unicode/utf8"
 
-	"golang.org/x/tools/go/gcimporter"
-	"golang.org/x/tools/go/types"
+	"golang.org/x/tools/go/gcimporter15"
 )
 
 const styleGuideBase = "https://golang.org/wiki/CodeReviewComments"
@@ -236,11 +236,30 @@
 
 var gcImporter = gcimporter.Import
 
+// importer implements go/types.Importer.
+// It also implements go/types.ImporterFrom, which was new in Go 1.6,
+// so vendoring will work.
+type importer struct {
+	impFn    func(packages map[string]*types.Package, path, srcDir string) (*types.Package, error)
+	packages map[string]*types.Package
+}
+
+func (i importer) Import(path string) (*types.Package, error) {
+	return i.impFn(i.packages, path, "")
+}
+
+func (i importer) ImportFrom(path, srcDir string, mode types.ImportMode) (*types.Package, error) {
+	return i.impFn(i.packages, path, srcDir)
+}
+
 func (p *pkg) typeCheck() error {
 	config := &types.Config{
 		// By setting a no-op error reporter, the type checker does as much work as possible.
-		Error:  func(error) {},
-		Import: gcImporter,
+		Error: func(error) {},
+		Importer: importer{
+			impFn:    gcImporter,
+			packages: make(map[string]*types.Package),
+		},
 	}
 	info := &types.Info{
 		Types:  make(map[ast.Expr]types.TypeAndValue),
@@ -397,7 +416,7 @@
 		s = ts
 	}
 	// Only non-main packages need to keep to this form.
-	if f.f.Name.Name != "main" && !strings.HasPrefix(s, prefix) {
+	if !f.pkg.main && !strings.HasPrefix(s, prefix) {
 		f.errorf(f.f.Doc, 1, link(ref), category("comments"), `package comment should be of the form "%s..."`, prefix)
 	}
 }
diff --git a/lint_test.go b/lint_test.go
index d4539b2..c12370f 100644
--- a/lint_test.go
+++ b/lint_test.go
@@ -14,14 +14,13 @@
 	"go/parser"
 	"go/printer"
 	"go/token"
+	"go/types"
 	"io/ioutil"
 	"path"
 	"regexp"
 	"strconv"
 	"strings"
 	"testing"
-
-	"golang.org/x/tools/go/types"
 )
 
 var lintMatch = flag.String("lint.match", "", "restrict testdata matches to this pattern")
@@ -274,7 +273,8 @@
 			t.Fatalf("Parsing %q: %v", src, err)
 		}
 		// use the package name as package path
-		pkg, err := types.Check(file.Name.Name, fset, []*ast.File{file})
+		config := &types.Config{}
+		pkg, err := config.Check(file.Name.Name, fset, []*ast.File{file}, nil)
 		if err != nil {
 			t.Fatalf("Type checking %q: %v", src, err)
 		}