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From: "hubicka at kam dot mff.cuni.cz" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug ipa/95558] [9/10/11/12 Regression] Invalid IPA optimizations
 based on weak definition
Date: Mon, 17 Jan 2022 17:32:10 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D95558

--- Comment #8 from hubicka at kam dot mff.cuni.cz ---
> > Do weak aliases fall under some implicit ODR here?
>=20
> The whole definition of "weak" is that it entitles you to make a definiti=
on
> that will be exempt from ODR, where a non-weak definition, if any, replac=
es it.

I fixed recently bug in pure-const discovery which made us to add
attributes to weaks while it should not, so perhaps this bug is gone.
For non-inline functions we should handle those as interposable.
Concerning warning, I we make difference between may and must warnings.
I think this is still useful do be diagnosed for user to consider
(perhaps there is a reason why all overwritters has to be weak), so I
think we should porduce may form of warning.

I will take a look.=