[arch-dev-public] RFC Final Comment Period: Enable LTO by default

[Allan McRae]

An RFC has now entered Final Comment Period. In 14 days, discussion will
end and the proposal will either be accepted, rejected or withdrawn:

https://gitlab.archlinux.org/archlinux/rfcs/-/merge_requests/4

Please visit the above link for discussion.


Summary: Enable LTO by default in our packages.


In the interests of a fair discussion, I will highlight the disadvantage
that was brought up during the initial discussion period:

The use of LTO can cause the memory usage of GBD to markedly increase.
It can also make debugging more difficult due to inlining across build
units.

Interestingly, the increased memory usage was bought up due to packages
that already use LTO in their build system!  But should be a
consideration for larger pieces of software.


Note that this RFC can not be implemented until pacman-6.0 is release
(which may or may not be a while away), unless a couple of small patches
are backported by the package maintainer.  It may be worth timing this
RFC and the buildflags one to occur at the same time.