On Fri, 24 Mar 2023 17:12:26 GMT, Julian Waters <jwat...@openjdk.org> wrote:
> A previous argument against link time optimization support that we have for > gcc is that it was extremely slow. After some checks it turns out we are > passing rather inefficient flags to gcc in optimized builds. Changing these > flags to run the linker optimizations in parallel and passing additional > flags to the compiler have the ability to speed this process up > significantly. Also fixes some incorrect flags passed to ld for linking as > well make/autoconf/flags-ldflags.m4 line 73: > 71: fi > 72: > 73: # Moved optimization flags to JvmFeatures.gmk, was -Wl,-O1 Please delete. This type of comment has no context when not seen in this PR. Nobody knows something else used to be here. make/hotspot/lib/JvmFeatures.gmk line 172: > 170: JVM_OPTIMIZATION := HIGHEST_JVM > 171: ifeq ($(call isCompiler, gcc), true) > 172: JVM_CFLAGS_FEATURES += -flto=$(JOBS) -fuse-linker-plugin > -fno-strict-aliasing -fno-fat-lto-objects `-fno-fat-lto-objects` has been the default for a while now ( at least gcc 10+) make/hotspot/lib/JvmFeatures.gmk line 173: > 171: ifeq ($(call isCompiler, gcc), true) > 172: JVM_CFLAGS_FEATURES += -flto=$(JOBS) -fuse-linker-plugin > -fno-strict-aliasing -fno-fat-lto-objects > 173: JVM_LDFLAGS_FEATURES += -O3 -flto=$(JOBS) -fuse-linker-plugin > -fno-strict-aliasing Shouldn't the `-O3` be using the `OPTIMIZATION` level in case it has been overridden from `HIGHEST_JVM`? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/13180#discussion_r1148798280 PR Review Comment: https://git.openjdk.org/jdk/pull/13180#discussion_r1148808588 PR Review Comment: https://git.openjdk.org/jdk/pull/13180#discussion_r1148811223
