qt5-qtwebengine-freeworld vs. aarch64

Hi, since chromium-freeworld, which is based on the same codebase and takes almost twice as long to build on x86_64 as qt5-qtwebengine-freeworld, has had several successful builds on aarch64: https://koji.rpmfusion.org/koji/packageinfo?packageID=506 I have decided to give qt5-qtwebengine-freeworld on aarch64 another try. Unfortunately, my 2 attempts so far have hit strange errors: 1. The first attempt built all the files coming from upstream Chromium, including several *jumbo*.cc ones that had caused trouble in the past, just fine, but then failed near the end building the Qt glue code: at 23703/23802, the build hit an OOM kill building obj/QtWebEngineCore/content_browser_client_qt.o: g++: fatal error: Killed signal terminated program cc1plus (This is one of the last files built as part of the Chromium build, then a successful build would move on to files built using qmake-qt5, which are not counted. But still, this is close to the end of the build process, and the heavy Chromium stuff has already been built at that point.) 2. The second attempt is even stranger: the aarch64 build task: https://koji.rpmfusion.org/koji/taskinfo?taskID=521517 got stuck in a really strange state where there is no log output anymore (there was at the beginning of the build, so it has vanished somewhere in the process). It looks like the builder crashed altogether. Do you have any idea how we can resolve the issue or should I just go back to building the package on x86_64 only? Kevin Kofler