3 files changed, 17 insertions, 20 deletions
diff --git a/src/debug/pe/file.go b/src/debug/pe/file.go
index de4bb9b736..06c160105f 100644
--- a/src/debug/pe/file.go
+++ b/src/debug/pe/file.go
@@ -20,6 +20,7 @@ import (
 	"compress/zlib"
 	"debug/dwarf"
 	"encoding/binary"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -165,7 +166,7 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		}
 		r2 := r
 		if sh.PointerToRawData == 0 { // .bss must have all 0s
-			r2 = zeroReaderAt{}
+			r2 = &nobitsSectionReader{}
 		}
 		s.sr = io.NewSectionReader(r2, int64(s.SectionHeader.Offset), int64(s.SectionHeader.Size))
 		s.ReaderAt = s.sr
@@ -182,15 +183,10 @@ func NewFile(r io.ReaderAt) (*File, error) {
 	return f, nil
 }
 
-// zeroReaderAt is ReaderAt that reads 0s.
-type zeroReaderAt struct{}
+type nobitsSectionReader struct{}
 
-// ReadAt writes len(p) 0s into p.
-func (w zeroReaderAt) ReadAt(p []byte, off int64) (n int, err error) {
-	for i := range p {
-		p[i] = 0
-	}
-	return len(p), nil
+func (*nobitsSectionReader) ReadAt(p []byte, off int64) (n int, err error) {
+	return 0, errors.New("unexpected read from section with uninitialized data")
 }
 
 // getString extracts a string from symbol string table.
@@ -363,6 +359,9 @@ func (f *File) ImportedSymbols() ([]string, error) {
 	var ds *Section
 	ds = nil
 	for _, s := range f.Sections {
+		if s.Offset == 0 {
+			continue
+		}
 		// We are using distance between s.VirtualAddress and idd.VirtualAddress
 		// to avoid potential overflow of uint32 caused by addition of s.VirtualSize
 		// to s.VirtualAddress.
diff --git a/src/debug/pe/file_test.go b/src/debug/pe/file_test.go
index 5368e08ad7..3d960ab7f3 100644
--- a/src/debug/pe/file_test.go
+++ b/src/debug/pe/file_test.go
@@ -511,17 +511,9 @@ main(void)
 	if bss == nil {
 		t.Fatal("could not find .bss section")
 	}
-	data, err := bss.Data()
-	if err != nil {
-		t.Fatal(err)
-	}
-	if len(data) == 0 {
-		t.Fatalf("%s file .bss section cannot be empty", objpath)
-	}
-	for _, b := range data {
-		if b != 0 {
-			t.Fatalf(".bss section has non zero bytes: %v", data)
-		}
+	// We expect an error from bss.Data, as there are no contents.
+	if _, err := bss.Data(); err == nil {
+		t.Error("bss.Data succeeded, expected error")
 	}
 }
 
diff --git a/src/debug/pe/section.go b/src/debug/pe/section.go
index fabb47af2e..70d0c220ce 100644
--- a/src/debug/pe/section.go
+++ b/src/debug/pe/section.go
@@ -97,11 +97,17 @@ type Section struct {
 }
 
 // Data reads and returns the contents of the PE section s.
+//
+// If s.Offset is 0, the section has no contents,
+// and Data will always return a non-nil error.
 func (s *Section) Data() ([]byte, error) {
 	return saferio.ReadDataAt(s.sr, uint64(s.Size), 0)
 }
 
 // Open returns a new ReadSeeker reading the PE section s.
+//
+// If s.Offset is 0, the section has no contents, and all calls
+// to the returned reader will return a non-nil error.
 func (s *Section) Open() io.ReadSeeker {
 	return io.NewSectionReader(s.sr, 0, 1<<63-1)
 }