src/jdk.compiler/share/classes/com/sun/tools/javac/code/Source.java

*** 237,10 ***
--- 237,12 ---
          RECORDS(JDK16, Fragments.FeatureRecords, DiagKind.PLURAL),
          SEALED_CLASSES(JDK17, Fragments.FeatureSealedClasses, DiagKind.PLURAL),
          CASE_NULL(JDK17, Fragments.FeatureCaseNull, DiagKind.NORMAL),
          PATTERN_SWITCH(JDK17, Fragments.FeaturePatternSwitch, DiagKind.PLURAL),
          REDUNDANT_STRICTFP(JDK17),
+         PRIMITIVE_CLASSES(JDK18, Fragments.FeaturePrimitiveClasses, DiagKind.PLURAL),
+         VALUE_CLASSES(JDK18, Fragments.FeatureValueClasses, DiagKind.PLURAL),
          ;
  
          enum DiagKind {
              NORMAL,
              PLURAL;