History of using -parameters for JDK builds

[Chen Liang]

Hi Liam,
I believe turning on -parameters is no longer as necessary with the introduction of JDK-8292275<https://bugs.openjdk.org/browse/JDK-8292275>, which enforces emission of relevant access flags for parameters that can affect core reflection behavior.
In addition, parameter name changes are not considered in the CSR process; relying on them would be risky.
Another event of note is that due to JDK-8058322<https://bugs.openjdk.org/browse/JDK-8058322>, such emitted parameters fail core reflection in JDK 8. A fix has since been backported by me.

I believe the main value of parameter is not to reflect on them, but to interpret the contents of signatures and annotations.  They omit some synthetic or mandated parameters, and only MethodParameters inform users which parameters exactly should be omitted.

Regards,
Chen Liang
________________________________
From: compiler-dev <compiler-dev-retn at openjdk.org> on behalf of Liam Miller-Cushon <cushon at google.com>
Sent: Tuesday, January 28, 2025 2:00 PM
To: compiler-dev at openjdk.org <compiler-dev at openjdk.org>
Subject: History of using -parameters for JDK builds

Hi,

I was wondering if anyone on the list knows of prior discussions about using -parameters when building the JDK itself. (compiler-dev@ isn't exactly the right list but I'm not sure where else to ask, enhanced-metadata-spec-discuss@ is archived.)

JEP 118 added support for -parameters and the corresponding model APIs to read parameter names. I understand why the change is opt-in, and there's some related discussion about that on the lists:

https://mail.openjdk.org/pipermail/enhanced-metadata-spec-discuss/2013-May/000200.html
https://mail.openjdk.org/pipermail/enhanced-metadata-spec-discuss/2013-May/000202.html

I was curious if there's been any discussion about enabling the feature specifically when building the JDK itself? All of the general concerns would apply there as well (class file size, compatibility surface).

I understand this isn't a small change, and am not making an argument for doing it, but I'm curious if this has already been considered and there's history on the lists I can read up on.
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