RFR: 8219810: javac throws NullPointerException [v4]

[Vicente Romero]

On Wed, 4 Jan 2023 15:59:54 GMT, Archie L. Cobbs <duke at openjdk.org> wrote:

>> JVMS 4.5 states:
>> 
>>> Each field of a class may have at most one of its ACC_PUBLIC, ACC_PRIVATE, and ACC_PROTECTED flags set (JLS §8.3.1), and must not have both its ACC_FINAL and ACC_VOLATILE flags set (JLS §8.3.1.4).
>> 
>> and JVMS 4.6 states:
>> 
>>> Each method of a class may have at most one of its ACC_PUBLIC, ACC_PRIVATE, and ACC_PROTECTED flags set (JLS §8.4.3). 
>> 
>> However, when reading class files these illegal combinations are not actually checked, and this can lead to compiler crashes as in the bug example.
>> 
>> This patch adds checks for these illegal combinations.
>
> Archie L. Cobbs has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Use Flags.toString() to stringify flag bits.

lgtm

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Marked as reviewed by vromero (Reviewer).

PR: https://git.openjdk.org/jdk/pull/10826