On Thu, 11 Aug 2022 04:18:58 GMT, Julian Waters <jwat...@openjdk.org> wrote:
> The support for Link Time Optimization in the JDK's make system could do with > some cleaning up, at the moment it simply assumes the compiler is gcc and > sets the flags as such. Instead of introducing changes in bulk, as a first > step, it would be good to simply supply the appropriate flags depending on > the compiler and refine the flags for the one existing compiler with support > for it. In practice the latter just means adding the proper > -fuse-linker-plugin to gcc compile step when link-time-opt is specified, as > without it the compiler generates both native code and information rich > representation for Link Time Optimization. With this flag, native code > generation is disabled and object files will contain only code required for > Link Time Optimization, thus speeding up compile times as well. I'll leave it to build folk to approve this. Making this contingent on using gcc seems reasonable. But I think we may end up just removing this anyway. Thanks. make/hotspot/lib/JvmFeatures.gmk line 173: > 171: ifeq ($(call check-jvm-feature, link-time-opt), true) > 172: ifeq ($(call isCompiler, gcc), true) > 173: # NOTE: Disable automatic opimization level and let the explicit > cflag control existing typo: opimization ------------- PR: https://git.openjdk.org/jdk/pull/9829