diff --git a/parser/fcode_block.go b/parser/fcode_block.go
index 8d36ffe..a837d2b 100644
--- a/parser/fcode_block.go
+++ b/parser/fcode_block.go
@@ -47,12 +47,14 @@ func (b *fencedCodeBlockParser) Open(parent ast.Node, reader text.Reader, pc Con
 		rest := line[i:]
 		left := util.TrimLeftSpaceLength(rest)
 		right := util.TrimRightSpaceLength(rest)
-		infoStart, infoStop := segment.Start+i+left, segment.Stop-right
-		value := rest[left : len(rest)-right]
-		if fenceChar == '`' && bytes.IndexByte(value, '`') > -1 {
-			return nil, NoChildren
-		} else if infoStart != infoStop {
-			info = ast.NewTextSegment(text.NewSegment(infoStart, infoStop))
+		if left < len(rest)-right {
+			infoStart, infoStop := segment.Start+i+left, segment.Stop-right
+			value := rest[left : len(rest)-right]
+			if fenceChar == '`' && bytes.IndexByte(value, '`') > -1 {
+				return nil, NoChildren
+			} else if infoStart != infoStop {
+				info = ast.NewTextSegment(text.NewSegment(infoStart, infoStop))
+			}
 		}
 	}
 	pc.Set(fencedCodeBlockInfoKey, &fenceData{fenceChar, findent, oFenceLength})
diff --git a/util/util.go b/util/util.go
index 7664d6f..c2bac4a 100644
--- a/util/util.go
+++ b/util/util.go
@@ -117,6 +117,7 @@ func VisualizeSpaces(bs []byte) []byte {
 	bs = bytes.Replace(bs, []byte(" "), []byte("[SPACE]"), -1)
 	bs = bytes.Replace(bs, []byte("\t"), []byte("[TAB]"), -1)
 	bs = bytes.Replace(bs, []byte("\n"), []byte("[NEWLINE]\n"), -1)
+	bs = bytes.Replace(bs, []byte("\r"), []byte("[CR]\n"), -1)
 	return bs
 }