RFR: 8342303: Segfault in update_inherited_vtable: AppCDS, old bytecode, and redefineClasses

[Calvin Cheung]

On Wed, 23 Oct 2024 17:15:53 GMT, Calvin Cheung <ccheung at openjdk.org> wrote:

> A simple fix to avoid referencing invalid vtable and itable entires in `InstanceKlass::restore_unshareable_info` if a class is not linked during CDS dump time.
> 
> Passed tiers 1 - 4 testing.
> 
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I've added two tests:

- redefine a super class loaded by the boot class loader;
- redefine an old super class loaded by the AppClassLoader.

Also simplified the OldClassAndRedefineClass.java test.

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PR Comment: https://git.openjdk.org/jdk/pull/21667#issuecomment-2445361621