RFR: JDK-8300531: MSVC CFlags look suspicious [v2]

[Justin King]

On Thu, 19 Jan 2023 19:23:30 GMT, Erik Joelsson <erikj at openjdk.org> wrote:

> Changing the global optimization flags is a pretty big and potentially intrusive change. It's quite possible that the current flags need a re-evaluation, since they were chosen a long time ago, for a much older version of Visual Studio. But, doing that evaluation is going to take some work. What is the impact on footprint and performance? How thoroughly have you tested that the increased optimization level isn't triggering something in Hotspot? We have quite a bit of history of compiler optimizations not working well with certain things that are done in the JVM.

Yes, I need to get my personal box back together so I can see the results on Windows. The main drawback of the changes is going to be binary size, the question is out much. I'll move this back to draft until I can see for myself. Based on compiler explorer -O2 is much more optimal than -O1 for certain things.

-------------

PR: https://git.openjdk.org/jdk/pull/12073