[Bug middle-end/96384] [11 Regression] bogus -Wstringop-overflow= storing into multidimensional array with index in range

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96384

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Martin Sebor <mse...@gcc.gnu.org>:

https://gcc.gnu.org/g:de05c19d5fd661ae16dd75a895b49d32d12f5edc

commit r11-3826-gde05c19d5fd661ae16dd75a895b49d32d12f5edc
Author: Martin Sebor <mse...@redhat.com>
Date:   Fri Oct 9 13:56:53 2020 -0600

    Correct handling of indices into arrays with elements larger than 1 (PR
c++/96511)

    Resolves:
    PR c++/96511 - Incorrect -Wplacement-new on POINTER_PLUS into an array with
4-byte elements
    PR middle-end/96384 - bogus -Wstringop-overflow= storing into
multidimensional array with index in range

    gcc/ChangeLog:

            PR c++/96511
            PR middle-end/96384
            * builtins.c (get_range): Return full range of type when neither
            value nor its range is available.  Fail for ranges inverted due
            to the signedness of offsets.
            (compute_objsize): Handle more special array members.  Handle
            POINTER_PLUS_EXPR and VIEW_CONVERT_EXPR that come up in front end
            code.
            (access_ref::offset_bounded): Define new member function.
            * builtins.h (access_ref::eval): New data member.
            (access_ref::offset_bounded): New member function.
            (access_ref::offset_zero): New member function.
            (compute_objsize): Declare a new overload.
            * gimple-array-bounds.cc (array_bounds_checker::check_array_ref):
Use
            enum special_array_member.
            * tree.c (component_ref_size): Use special_array_member.
            * tree.h (special_array_member): Define a new type.
            (component_ref_size): Change signature.

    gcc/cp/ChangeLog:

            PR c++/96511
            PR middle-end/96384
            * init.c (warn_placement_new_too_small): Call builtin_objsize
instead
            of duplicating what it does.

    gcc/testsuite/ChangeLog:

            PR c++/96511
            PR middle-end/96384
            * g++.dg/init/strlen.C: Add expected warning.
            * g++.dg/warn/Wplacement-new-size-1.C: Relax warnings.
            * g++.dg/warn/Wplacement-new-size-2.C: Same.
            * g++.dg/warn/Wplacement-new-size-6.C: Same.
            * gcc.dg/Warray-bounds-58.c: Adjust
            * gcc.dg/Wstringop-overflow-37.c: Same.
            * g++.dg/warn/Wplacement-new-size-7.C: New test.