RFR: 8307858: [REDO] JDK-8307194 Add make target for optionally building a complete set of all JDK and hotspot libjvm static libraries [v4]

[Jiangli Zhou]

On Wed, 24 May 2023 20:52:38 GMT, Erik Joelsson <erikj at openjdk.org> wrote:

> > My build job is still running, but it has failed in two distinct ways already. See below for mac fix. Our cross build of arm32 fails with this message:
> > ```
> > [2023-05-24T19:25:15,310Z] /opt/mach5/mesos/work_dir/jib-master/install/jpg/infra/builddeps/devkit-linux_x64-to-linux_arm/gcc8.2.0-Fedora27+1.0/devkit-linux_x64-to-linux_arm-gcc8.2.0-Fedora27+1.0.tar.gz/x86_64-linux-gnu-to-arm-linux-gnueabihf/bin/../lib/gcc/arm-linux-gnueabihf/8.2.0/../../../../arm-linux-gnueabihf/bin/ld: fatal error: cannot mix -r with dynamic object /opt/mach5/mesos/work_dir/jib-master/install/jpg/infra/builddeps/devkit-linux_x64-to-linux_arm/gcc8.2.0-Fedora27+1.0/devkit-linux_x64-to-linux_arm-gcc8.2.0-Fedora27+1.0.tar.gz/x86_64-linux-gnu-to-arm-linux-gnueabihf/bin/../lib/gcc/arm-linux-gnueabihf/8.2.0/../../../../arm-linux-gnueabihf/lib/libstdc++.so
> > ```
> 
> If this is a problem with your partial link solution, then perhaps just employing the relative path trick for the `ar` command line on mac could be enough to handle long paths and lots of object files? That appears to be how we handle it with clang for linking already due to @-file problems.

The partial linking was originally suggested by C++/Clang toolchain folks to mitigate linker overhead that was observed during final executable link time. For a static library containing any object file (`.o`) that was compiled with ThinLTO (https://clang.llvm.org/docs/ThinLTO.html) enabled, linking an executable using the static library without distributed ThinLTO could experience more overhead and slow down linking. Solving the macosx `ar` limitation is a side-effect/benefit of using partial linking. We probably would want to include the partial linking even without the `ar` limitation.

Is it possible `$$($1_SYSROOT_LDFLAGS)` pulled in `libstdc++.so` as part of the input for partial linking with the linux-aarch64 cross build?

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PR Comment: https://git.openjdk.org/jdk/pull/14064#issuecomment-1561969001