src/share/classes/com/sun/tools/javac/comp/Attr.java

*** 2989,2998 ****
--- 2989,3000 ----
          Type owntype = types.createErrorType(tree.type);
          if (operator.kind == MTH &&
                  !left.isErroneous() &&
                  !right.isErroneous()) {
              owntype = operator.type.getReturnType();
+             // This will figure out when unboxing can happen and
+             // choose the right comparison operator.
              int opc = chk.checkOperator(tree.lhs.pos(),
                                          (OperatorSymbol)operator,
                                          tree.getTag(),
                                          left,
                                          right);
*** 3016,3028 ****
                      }
                  }
              }
  
              // Check that argument types of a reference ==, != are
!             // castable to each other, (JLS???).
              if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
!                 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
                      log.error(tree.pos(), "incomparable.types", left, right);
                  }
              }
  
              chk.checkDivZero(tree.rhs.pos(), operator, right);
--- 3018,3032 ----
                      }
                  }
              }
  
              // Check that argument types of a reference ==, != are
!             // castable to each other, (JLS 15.21).  Note: unboxing
!             // comparisons will not have an acmp* opc at this point.
              if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
!                 if (!types.isEqualityComparable(left, right,
!                                                 new Warner(tree.pos()))) {
                      log.error(tree.pos(), "incomparable.types", left, right);
                  }
              }
  
              chk.checkDivZero(tree.rhs.pos(), operator, right);