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From: "marxin at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug lto/102649] GCC 9.3.1 LTO bug -- incorrect function call, bad
 stack arguments pushed
Date: Tue, 12 Oct 2021 13:10:48 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102649

--- Comment #3 from Martin Li=C5=A1ka <marxin at gcc dot gnu.org> ---
All right, so being in the described situation I would recommend the follow=
ing
steps:

1) please try bisecting GCC revisions and find the first on that fixed the
issue in between version 9.x and 10.x release. That would tell us more.

2) You can experiment with -fno-lto, which you can use for a subset of obje=
ct
files (the rest will be built with LTO). Doing that, you will be able to
isolate that to a minimal set of objects that need -flto in order to expose=
 the
issue.

3) You can use -fdump-tree-all for LTO linking step and you can investigate=
 if
the caller really calls the function with an argument being set to 0.=