diff --git a/semantic/checker.go b/semantic/checker.go
index 40f07874..de929723 100644
--- a/semantic/checker.go
+++ b/semantic/checker.go
@@ -145,11 +145,28 @@ func (c *checker) CheckStructLikes(t *parser.Thrift) (warns []string, err error)
 				warns = append(warns, fmt.Sprintf("non-positive ID %d of field %q in %q",
 					f.ID, f.Name, s.Name))
 			}
+			if containByteType(f.Type) {
+				warns = append(warns, fmt.Sprintf("field %q in %q is still using 'byte'. The 'byte' type is a compatibility alias for 'i8'. Use 'i8' to emphasize the signedness of this type. If you want to generate '[]byte', please use 'binary' in thrift IDL.",
+					f.Name, s.Name))
+			}
 		}
 	}
 	return
 }
 
+func containByteType(t *parser.Type) bool {
+	if parser.Typename2TypeID(t.Name) == parser.BYTE {
+		return true
+	}
+	if t.KeyType != nil && containByteType(t.KeyType) {
+		return true
+	}
+	if t.ValueType != nil && containByteType(t.ValueType) {
+		return true
+	}
+	return false
+}
+
 // CheckUnions checks the semantics of union nodes.
 func (c *checker) CheckUnions(t *parser.Thrift) (warns []string, err error) {
 	for _, u := range t.Unions {
diff --git a/version/version.go b/version/version.go
index 20fcf801..a68f9439 100644
--- a/version/version.go
+++ b/version/version.go
@@ -14,4 +14,4 @@
 
 package version
 
-const ThriftgoVersion = "0.3.18"
+const ThriftgoVersion = "0.3.19"