[Bug middle-end/102633] [11/12 Regression] warning for self-initialization despite -Wno-init-self

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102633

--- Comment #11 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Jakub Jelinek
<jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:aabebf76e9d9a805ea5b443d4ee4f49f13155d87

commit r12-9160-gaabebf76e9d9a805ea5b443d4ee4f49f13155d87
Author: Marek Polacek <polacek@redhat.com>
Date:   Tue Jul 26 13:55:58 2022 -0400

    c-family: Honor -Wno-init-self for cv-qual vars [PR102633]

    Since r11-5188-g32934a4f45a721, we drop qualifiers during l-to-r
    conversion by creating a NOP_EXPR.  For e.g.

      const int i = i;

    that means that the DECL_INITIAL is '(int) i' and not 'i' anymore.
    Consequently, we don't suppress_warning here:

    711     case DECL_EXPR:
    715       if (VAR_P (DECL_EXPR_DECL (*expr_p))
    716           && !DECL_EXTERNAL (DECL_EXPR_DECL (*expr_p))
    717           && !TREE_STATIC (DECL_EXPR_DECL (*expr_p))
    718           && (DECL_INITIAL (DECL_EXPR_DECL (*expr_p)) == DECL_EXPR_DECL
(*expr_p))
    719           && !warn_init_self)
    720         suppress_warning (DECL_EXPR_DECL (*expr_p), OPT_Winit_self);

    because of the check on line 718 -- (int) i is not i.  So -Wno-init-self
    doesn't disable the warning as it's supposed to.

    The following patch fixes it by moving the suppress_warning call from
    c_gimplify_expr to the front ends, at points where we haven't created
    the NOP_EXPR yet.

            PR middle-end/102633

    gcc/c-family/ChangeLog:

            * c-gimplify.cc (c_gimplify_expr) <case DECL_EXPR>: Don't call
            suppress_warning here.

    gcc/c/ChangeLog:

            * c-parser.cc (c_parser_initializer): Add new tree parameter.  Use
it.
            Call suppress_warning.
            (c_parser_declaration_or_fndef): Pass d down to
c_parser_initializer.
            (c_parser_omp_declare_reduction): Pass omp_priv down to
            c_parser_initializer.

    gcc/cp/ChangeLog:

            * decl.cc (cp_finish_decl): Call suppress_warning.

    gcc/testsuite/ChangeLog:

            * c-c++-common/Winit-self1.c: New test.
            * c-c++-common/Winit-self2.c: New test.

    (cherry picked from commit 04ce2400b35225302e0d6883bb0817378180f5d7)