RFR: 8349754: Invalid "early reference" error when class extends an outer class [v3]

[Archie Cobbs]

On Tue, 13 May 2025 16:04:33 GMT, Archie Cobbs <acobbs at openjdk.org> wrote:

>> The compiler is generating a bogus error for this input:
>> 
>> $ cat Outer.java
>> class Outer {
>>     private int i;
>>     class Sub extends Outer {
>>         Sub() {
>>             i = 42;
>>             super();
>>         }
>>     }
>> }
>> $ javac --enable-preview --source 24 Outer.java
>> Outer.java:5: error: cannot reference i before supertype constructor has been called
>>             i = 42;
>>             ^
>> Note: Outer.java uses preview features of Java SE 24.
>> Note: Recompile with -Xlint:preview for details.
>> 1 error 
>> 
>> 
>> The trick here is that the expression `i` refers to `Outer.this.i`, not `this.i`, but the error checking logic is mistakenly assuming the latter. This patch adds an exception for this case, which happens when the field is `private` and declared in a class which is both a superclass and an outer class.
>
> Archie Cobbs has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains three commits:
> 
>  - Merge branch 'master' into JDK-8349754 to fix conflict.
>  - Simplify logic using Symbol.isMemberOf() per review suggestion.
>  - Fix incorrect "early reference" error.

Thanks for the review!

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PR Comment: https://git.openjdk.org/jdk/pull/23545#issuecomment-2884431411