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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/104060] [11/12 Regression]
 -Wmaybe-uninitialized false alarm on address of local array
Date: Mon, 17 Jan 2022 08:45:02 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104060

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2
                 CC|                            |hubicka at gcc dot gnu.org,
                   |                            |msebor at gcc dot gnu.org,
                   |                            |rguenth at gcc dot gnu.org

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Note we can eventually use modref info in the "wrong way" to query whether =
the
argument is dereferenced.  Note it can only alswer the question whether it
may be dereferenced or whether it kills (via stores) a specific range based=
 on
it, both are not an exact match here since modref will conservatively say
the argument is dereferenced.

But I agree with Andrew - with the above we could make the warning only tri=
gger
for local functions GCC saw the body for (or with LTO bodies analyzed during
IPA but now in another LTRANS unit).  That should eventually reduce the num=
ber
of false positives.=