diff --git a/parser/lexer.go b/parser/lexer.go
index 9484c14ad6..3adfb47ffb 100644
--- a/parser/lexer.go
+++ b/parser/lexer.go
@@ -211,9 +211,11 @@ func (s *Scanner) Lex(v *yySymType) int {
 	case quotedIdentifier:
 		tok = identifier
 	}
-	if tok == unicode.ReplacementChar && s.r.eof() {
-		return 0
+
+	if tok == unicode.ReplacementChar {
+		return invalid
 	}
+
 	return tok
 }
 
diff --git a/parser/lexer_test.go b/parser/lexer_test.go
index 9bcddf7eeb..6da200367c 100644
--- a/parser/lexer_test.go
+++ b/parser/lexer_test.go
@@ -356,18 +356,18 @@ func (s *testLexerSuite) TestSQLModeANSIQuotes(c *C) {
 
 func (s *testLexerSuite) TestIllegal(c *C) {
 	table := []testCaseItem{
-		{"'", 0},
-		{"'fu", 0},
-		{"'\\n", 0},
-		{"'\\", 0},
+		{"'", invalid},
+		{"'fu", invalid},
+		{"'\\n", invalid},
+		{"'\\", invalid},
 		{fmt.Sprintf("%c", 0), invalid},
-		{"`", 0},
-		{`"`, 0},
-		{"@`", 0},
-		{"@'", 0},
-		{`@"`, 0},
-		{"@@`", 0},
-		{"@@global.`", 0},
+		{"`", invalid},
+		{`"`, invalid},
+		{"@`", invalid},
+		{"@'", invalid},
+		{`@"`, invalid},
+		{"@@`", invalid},
+		{"@@global.`", invalid},
 	}
 	runTest(c, table)
 }