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From: "wilco at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug libgcc/105708] libgcc: aarch64: init_lse_atomics can race with
 user-defined constructors
Date: Tue, 24 May 2022 11:15:35 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105708

--- Comment #12 from Wilco <wilco at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #11)
> How can changing the constructor priority in libgcc affect anything?
> Constructor priorities are within the same shared library or within the s=
ame
> executable, not inside of the same process.  So, e.g. when using
> libgcc_s.so.1,
> it might change order with other constructors inside of that shared libra=
ry
> (there are likely none), but nothing else.  For libgcc.a, it might affect
> even ctors of the other objects with which the library is linked, but sti=
ll
> not between different shared libraries or binaries.

The outline atomics are linked with each .so (to avoid the PLT and GOT), so
there are multiple copies and any initialization order issues are within the
.so.=