src/share/classes/com/sun/tools/javac/code/Symtab.java

*** 146,155 ****
--- 146,156 ----
      public final Type deprecatedType;
      public final Type suppressWarningsType;
      public final Type inheritedType;
      public final Type proprietaryType;
      public final Type systemType;
+     public final Type autoCloseableType;
  
      /** The symbol representing the length field of an array.
       */
      public final VarSymbol lengthVar;
  
*** 157,166 ****
--- 158,170 ----
      public final OperatorSymbol nullcheck;
  
      /** The symbol representing the final finalize method on enums */
      public final MethodSymbol enumFinalFinalize;
  
+     /** The symbol representing the close method on TWR AutoCloseable type */
+     public final MethodSymbol autoCloseableClose;
+ 
      /** The predefined type that belongs to a tag.
       */
      public final Type[] typeOfTag = new Type[TypeTags.TypeTagCount];
  
      /** The name of the class that belongs to a basix type tag.
*** 442,451 ****
--- 446,461 ----
          retentionType = enterClass("java.lang.annotation.Retention");
          deprecatedType = enterClass("java.lang.Deprecated");
          suppressWarningsType = enterClass("java.lang.SuppressWarnings");
          inheritedType = enterClass("java.lang.annotation.Inherited");
          systemType = enterClass("java.lang.System");
+         autoCloseableType = enterClass("java.lang.AutoCloseable");
+         autoCloseableClose = new MethodSymbol(PUBLIC,
+                              names.close,
+                              new MethodType(List.<Type>nil(), voidType,
+                                             List.of(exceptionType), methodClass),
+                              autoCloseableType.tsym);
  
          synthesizeEmptyInterfaceIfMissing(cloneableType);
          synthesizeEmptyInterfaceIfMissing(serializableType);
          synthesizeEmptyInterfaceIfMissing(polymorphicSignatureType);
          synthesizeBoxTypeIfMissing(doubleType);