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From: "msebor at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c/101836] __builtin_object_size(P->M, 1) where M is an array
 and the last member of a struct fails
Date: Wed, 13 Oct 2021 02:11:00 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101836

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-10-13
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
                 CC|                            |msebor at gcc dot gnu.org,
                   |                            |siddhesh at redhat dot com

--- Comment #4 from Martin Sebor <msebor at gcc dot gnu.org> ---
I'm not sure how feasible it is to change __builtin_object_size or to add an
option to control this behavior but I agree that treating all trailing arra=
ys
as flexible array members is overly permissive and unhelpful (GCC warnings =
like
-Warray-bounds are stricter and treat only zero and one-element arrays that
way).  Let me confirm this request and CC Siddhesh who just submitted a pat=
ch
for __builtin_dynamic_object_size.  Maybe that's a way toward something
stricter.=