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From: "qinzhao at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/101836] __builtin_object_size(P->M, 1) where M is an
 array and the last member of a struct fails
Date: Fri, 10 Jun 2022 20:24:48 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101836

--- Comment #16 from qinzhao at gcc dot gnu.org ---
additional work are needed in order to make this task complete:

1. add one more new gcc option:

-fstrict-flex-arrays

when it's on, only treat the following cases as flexing array:

trailing array with size 0;
trailing array with size 1;
trailing flexible array;

all other trailing arrays with size > 1 will be treated as normal arrays.=20


2. there a lot of places in GCC that currently assume all trailing arrays as
flexible array, we might need to update all these places altogether to make=
 GCC
behavior consistently.=20

As I checked, most of the places used an old routine array_at_struct_end_p,=
 we
might need to replace all the usage of "array_at_struct_end_p" with the new
option + the more strict checking on flexing trailing array.=20

let me know if you have any comments and suggestions.=