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From: "amonakov at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/106943] GCC building clang/llvm with LTO flags causes ICE
 in clang
Date: Sat, 13 May 2023 06:30:09 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106943

--- Comment #31 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
(In reply to Xi Ruoyao from comment #28)
> "To put it simply, operator delete for class User inspects memory of the
> object after the end of its lifetime. This shows as a use-after-dtor error
> when running under MemorySanitizer."
>=20
> So it seems technically we'll need -fno-lifetime-dse here?  Our docs say
> -flifetime-dse only "preserve stores before the constructor starts" but
> "still treat the object as dead after the destructor".

Agreed, -fno-lifetime-dse seems appropriate here. Thank you for proposing a
patch on the LLVM side!=