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From: "xry111 at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/110368] Incorrect "is used uninitialized" warning message
Date: Sat, 07 Oct 2023 06:36:49 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110368

Xi Ruoyao <xry111 at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |xry111 at gcc dot gnu.org

--- Comment #8 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
(In reply to Sam James from comment #7)
> That said, I suppose we should do better here with -Wstrict-aliasing. No
> level detects it.

I think it's very difficult to make -Wstrict-aliasing really useful.  A
sanitizer at runtime would be much more useful but the develop of such a
sanitizer seems stalled
(https://discourse.llvm.org/t/reviving-typesanitizer-a-sanitizer-to-catch-t=
ype-based-aliasing-violations/).

For now we can only compare the output with or without -fno-strict-aliasing=
.=20
And we are already saying "try -fno-strict-aliasing" in the bug report
guidance.=