This is a tracking bug for Change: LTO Build Improvements For more details, see: https://fedoraproject.org/wiki/Changes/LTOBuildImprovements Currently all packages that are not opted out of LTO include -ffat-lto-objects in their build flags. This proposal would remove -ffat-lto-objects from the default LTO flags and only use it for packages that actually need it.
This has landed. https://src.fedoraproject.org/rpms/fedora-release/pull-request/181
(In reply to Matthew Miller from comment #1) > This has landed. > https://src.fedoraproject.org/rpms/fedora-release/pull-request/181 It does not seem to be related. Are you sure you referenced the PR in the right ticket?
not sure this belongs here, but renderdoc with lto broke earlier in a way that isn't noticeable without running it https://bugzilla.redhat.com/show_bug.cgi?id=1955122 unsure if -ffat-lto-objects makes it work
@mattdm That update was for rhbz1944428 right? I don't think this change has landed.
I'm confused about the status of this change: https://fedoraproject.org/wiki/Changes/LTOBuildImprovements says it's accepted for F35, links to a FesCo ticket which accepted it for F34, and that ticket links to an unrelated devel-ml-post. Also, the change mentions "The feature owner (Jeff Law) will need to settle on a suitable RPM macro to indicate an opt-in" and I see no such macro there. (I can change build flags myself, of course.) The bug here references an unrelated dist-git PR. This adds quite some confusion to a topic which can be confusing as is already for us poor little packagers who are not build chain experts. Maybe, as a starter, document (in that change) the location of the default flags or how to check them.
OK, so by https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/I3FP5V56NKCU24XDJDCMIOFQ2B6YQLMY/ the change owner left RH and the change is not implemented. I take it that means: We build with fat LTO everywhere and there is no special opt-in or opt-out other than adding build flags directly. Do we have "%{_lto_cflags}" or is that a SuSE-only thing?
This bug appears to have been reported against 'rawhide' during the Fedora Linux 36 development cycle. Changing version to 36.