RFR: 8371893: [macOS aarch64] use dead_strip linker option to reduce binary size

[Matthias Baesken]

On Wed, 19 Nov 2025 18:53:34 GMT, Chris Plummer <cjplummer at openjdk.org> wrote:

> This seems to work:
> 
> ```
> extern void* _ZTV8Metadata[];
> 
> __attribute__((used))
>  void* foo() {
>   return _ZTV8Metadata[0];
> }
> ```
> 
> You can put this anywhere since it does not reference any hotspot types. It just needs to be linked in with libjvm. Note I tried putting the "used" attribute on _ZTV8Metadata and getting rid of the foo() part, but I got the following warning and the vtable was dead stripped:
> 
> `warning: 'used' attribute ignored on a non-definition declaration [-Wignored-attributes]`


Thanks for the testing and providing the workaround.  Too bad   that the 'retain' and 'used' are only function attributes, this makes things a bit harder.

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PR Comment: https://git.openjdk.org/jdk/pull/28319#issuecomment-3558408585