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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/100124] Why is "flexible array member '...' in an otherwise
 empty '...'" an issue?
Date: Tue, 20 Apr 2021 20:30:55 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D100124

--- Comment #7 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Behdad Esfahbod from comment #6)
> > But I will note GCC treats (all) arrays at the end of a POD struct as a
> > flexible one so the question I have is more about the ubsan issue you a=
re
> > running into, is that with GCC or with clang/LLVM?
>=20
> The ubsan issue reported to us is with gcc:
> https://github.com/harfbuzz/harfbuzz/issues/2953#issuecomment-823460893

Can you report that as a bug as GCC's rule is treat all arrays that end a P=
OD
as a flexiable array?  Please include the full preprocessed source that
produces the problem at runtime and the specific version of GCC that is use=
d.=20
This is a GCC bug in mind due to this unless there is another field missing
that is in the source that you are not showing.=