[Bug c/51628] __attribute__((packed)) is unsafe in some cases (i.e. add -Waddress-of-packed-member, etc.)

[hjl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51628

--- Comment #61 from hjl at gcc dot gnu.org <hjl at gcc dot gnu.org> ---
Author: hjl
Date: Fri Jan 18 13:05:18 2019
New Revision: 268075

URL: https://gcc.gnu.org/viewcvs?rev=268075&root=gcc&view=rev
Log:
c-family: Update unaligned adress of packed member check

Check unaligned pointer conversion and strip NOPS.

gcc/c-family/

        PR c/51628
        PR c/88664
        * c-common.h (warn_for_address_or_pointer_of_packed_member):
        Remove the boolean argument.
        * c-warn.c (check_address_of_packed_member): Renamed to ...
        (check_address_or_pointer_of_packed_member): This.  Also
        warn pointer conversion.
        (check_and_warn_address_of_packed_member): Renamed to ...
        (check_and_warn_address_or_pointer_of_packed_member): This.
        Also warn pointer conversion.
        (warn_for_address_or_pointer_of_packed_member): Remove the
        boolean argument.  Don't check pointer conversion here.

gcc/c

        PR c/51628
        PR c/88664
        * c-typeck.c (convert_for_assignment): Upate the
        warn_for_address_or_pointer_of_packed_member call.

gcc/cp

        PR c/51628
        PR c/88664
        * call.c (convert_for_arg_passing): Upate the
        warn_for_address_or_pointer_of_packed_member call.
        * typeck.c (convert_for_assignment): Likewise.

gcc/testsuite/

        PR c/51628
        PR c/88664
        * c-c++-common/pr51628-33.c: New test.
        * c-c++-common/pr51628-35.c: New test.
        * c-c++-common/pr88664-1.c: Likewise.
        * c-c++-common/pr88664-2.c: Likewise.
        * gcc.dg/pr51628-34.c: Likewise.

Added:
    trunk/gcc/testsuite/c-c++-common/pr51628-33.c
    trunk/gcc/testsuite/c-c++-common/pr51628-35.c
    trunk/gcc/testsuite/c-c++-common/pr88664-1.c
    trunk/gcc/testsuite/c-c++-common/pr88664-2.c
    trunk/gcc/testsuite/gcc.dg/pr51628-34.c
Modified:
    trunk/gcc/c-family/ChangeLog
    trunk/gcc/c-family/c-common.h
    trunk/gcc/c-family/c-warn.c
    trunk/gcc/c/ChangeLog
    trunk/gcc/c/c-typeck.c
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/call.c
    trunk/gcc/cp/typeck.c
    trunk/gcc/testsuite/ChangeLog