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From: "andi-gcc at firstfloor dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug lto/107014] flatten+lto fails the kernel build
Date: Sun, 25 Sep 2022 19:56:38 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107014

Andi Kleen <andi-gcc at firstfloor dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |andi-gcc at firstfloor dot=
 org

--- Comment #9 from Andi Kleen <andi-gcc at firstfloor dot org> ---
I suspect what happens is that it hits in some kernel initialization functi=
on.
If they don't use initcall the LTO build can all inline them into each other
(because they are only called once) creating a single big initialization
function. With flatten that will create an extremely large function that ta=
kes
a long time to process.

I suspect any use of flatten is better using always_inline, since that affe=
cts
only a single function. Should probably be fixed upstream in the kernel.=