On Wed, 4 Sep 2024 23:24:13 GMT, Jiangli Zhou <jian...@openjdk.org> wrote:
>> As a prerequisite for Hermetic Java, we need a statically linked `java` >> launcher. It should behave like the normal, dynamically linked `java` >> launcher, except that all JDK native libraries should be statically, not >> dynamically, linked. >> >> This patch is the first step towards this goal. It will generate a >> `static-jdk` image with a statically linked launcher. This launcher is >> missing several native libs, however, and does therefore not behave like a >> proper dynamic java. One of the reasons for this is that local symbol hiding >> in static libraries are not implemented yet, which causes symbol clashes >> when linking all static libraries together. This will be addressed in an >> upcoming patch. >> >> All changes in the `src` directory are copied from, or inspired by, changes >> made in [the hermetic-java-runtime branch in Project >> Leyden](https://github.com/openjdk/leyden/tree/hermetic-java-runtime). > > make/StaticLibs.gmk line 1: > >> 1: # > > Perhaps also consider adopting StaticLink.gmk file name from the > https://github.com/openjdk/leyden/tree/hermetic-java-runtime/ branch, as we > are mostly doing the static linking here. Creating the static libs is handled > elsewhere. My intention is to move all relevant handling of static linking into this file. > make/StaticLibs.gmk line 118: > >> 116: OPTIMIZATION := HIGH, \ >> 117: STATIC_LAUNCHER := true, \ >> 118: LDFLAGS := $(JAVASTATIC_LINK_LDFLAGS), \ > > I could be missing something, but I don't see where is > $JAVASTATIC_LINK_LDFLAGS defined. > > On a related notes, I think we need to include $JVM_LDFLAGS when linking the > static "java". See > https://bugs.openjdk.org/browse/JDK-8339522?focusedId=14702923&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-14702923. You are right, this is dead code. Thanks for spotting this. During my experimentation, I tried passing along LDFLAGS from the individual libraries as well, but it turned out not to be a good idea -- the way we have used them were to modify some special properties on a single dynamic library, which did not apply to the static library as a whole. However, there is a risk that we in the future need to add LDFLAGS to a library that also needs to be carried over to the static launcher. If this happens, I guess we need to separate between LDFLAGS_ONLY_FOR_THIS_DLL and LDFLAGS_ALSO_FOR_STATIC_LINKING. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/20837#discussion_r1745180739 PR Review Comment: https://git.openjdk.org/jdk/pull/20837#discussion_r1745180044
