Many thanks Erik and Julian for the pointers, I'll explore the --with-build-jdk suggestion, and opened a bug report: - https://bugs.openjdk.org/browse/JDK-8334617
On Thu, Jun 20, 2024 at 9:53 AM <erik.joels...@oracle.com> wrote: > > On 6/20/24 01:01, Sanne Grinovero wrote: > > Hi all, > > > > I was hoping to build a custom JVM which would only have G1GC as a > > garbage collector, for some experiments. > > > > Essentially I'm running: > > > >> bash configure --with-jvm-variants=custom > >> --with-jvm-features=cds,compiler1,compiler2,g1gc,jfr,jni-check,jvmci,jvmti,management,services,link-time-opt > >> --enable-generate-classlist --disable-manpages > >> --with-vendor-name=Experiments > > However then during the "make images" step, this will fail when the > > jmod(s) are being created, with a long sequence of errors such as: > > > > Creating java.security.jgss.jmod > > Error occurred during initialization of VM > > Option -XX:+UseSerialGC not supported > > > > The same build succeeds if I add the "serialgc" in the list of > > selected features. > > > > Should I open a bug report? > > I've verified that both the `master` branch and `jdk23` are affected, > > and so is the `premain` branch on the Leyden fork. > Yes, I think that may be warranted, however see workaround below. > > I'm assuming that it should be supported to build a JVM without the > > serialgc implementation since it's listed as a feature and therefore > > I'd expect it to be OK to disable it, however I'm wondering about this > > explicitly stated need during the jmod building process; is there > > perhaps a specific need for these to be built with the serialgc, or is > > this just a hint meant to make the build more efficient? > > There is no specific need, this is just for efficiency. Using the > "small" java configuration, saves considerable user time for small short > lived java processes. We currently don't take any limitations in the > configuration for the built JDK into account when using it as the > "BUILD_JDK" during the build. Perhaps we should. On the other hand, if > you are building a limited JDK through configuration options, it can > often be adviceable to supply a separate BUILD_JDK (for performing the > build steps that need a JDK N). This can be done by first building a > standard configuration and then pointing to that JDK image with the > configure arg --with-build-jdk. > > /Erik > > > Many thanks, > > Sanne Grinovero > > >
