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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/102606] large array in a dead-code is not optimized
 away at -O0
Date: Tue, 05 Oct 2021 16:17:46 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102606

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

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

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Or VLA.
Anyway, even at -O0 we can optimize away some if (0)s, but we need assurance
that there are no labels in there and that the code really dead.  So, e.g. =
if
constexpr (0) can be optimized away because there is a language guarantee t=
hat
one can't jump into those bodies.=