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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/95663] static_cast checks for null even when
 the pointer is dereferenced
Date: Mon, 15 Jun 2020 13:32:22 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D95663

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

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

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to rguenther@suse.de from comment #8)
> -fdelete-null-pointer-checks optimizes NULL pointer checks _after_ a
> dereference.  This case is first checking and then dereferencing.
> GCC sees

-fdelete-null-pointer-checks is just an option that says that it is ok to
optimize null pointer dereferences.
So, I don't see why we couldn't optimize this out.
-fisolate-erroneous-paths-dereference is documented to add __builtin_trap in
there instead of __builtin_unreachable, I'd say we want (by default) someth=
ing
that will add __builtin_unreachable in those cases instead.=