On Wed, 29 Oct 2025 12:59:07 GMT, Matthias Baesken <[email protected]> wrote:
>> We currently have support for LTO (link time optimization) for >> Hotspot/libjvm, that can be enabled as a JVM feature. >> But for other JDK native libs, we do not have support for this feature. >> LTO and sometimes lead to faster and also in some cases smaller binaries, so >> support for this might be interesting also for other libs and not only >> libjvm. > > Matthias Baesken has updated the pull request incrementally with one > additional commit since the last revision: > > Do not enable LTO for some libs in this PR This change on its own doesn't do anything. Do you plan on following up immediately with a set of suggested libs to enable this on? Have you noticed any impact on build performance when enabling this on any JDK libs? I very much doubt any component owner is going to test and apply this on their own. Without that, this is a dead feature and I wouldn't want it to go in. I wonder if it would be a good idea to add a global on/off switch (configure arg) for this whole thing, I'm really not sure. It kind of depends on what the impact is. If the impact is unknown, then a global on/off switch, default off, would let every distributor evaluate this on their own. That would of course also require that at least some libs have this enabled. make/common/NativeCompilation.gmk line 101: > 99: # SYSROOT_LDFLAGS the linker flags for using the specific sysroot > 100: # OPTIMIZATION sets optimization level to NONE, LOW, HIGH, HIGHEST, > HIGHEST_JVM, SIZE > 101: # LINK_TIME_OPTIMIZATION if set to true, it enables additionally link > time optimization Suggestion: # LINK_TIME_OPTIMIZATION if set to true, enables link time optimization ------------- PR Review: https://git.openjdk.org/jdk/pull/27976#pullrequestreview-3393619643 PR Review Comment: https://git.openjdk.org/jdk/pull/27976#discussion_r2473244871
