[Bug analyzer/112969] -Wanalyzer-exposure-through-uninit-copy false positive seen on Linux kernel's drivers/net/ethernet/intel/ice/ice_ptp.c

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112969

--- Comment #2 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by David Malcolm <dmalcolm@gcc.gnu.org>:

https://gcc.gnu.org/g:6426d466779fa889bca170e3ff80dbfc6ea8c2e8

commit r14-8428-g6426d466779fa889bca170e3ff80dbfc6ea8c2e8
Author: David Malcolm <dmalcolm@redhat.com>
Date:   Thu Jan 25 10:06:12 2024 -0500

    analyzer: fix defaults in compound assignments from non-zero offsets
[PR112969]

    Confusion in binding_cluster::maybe_get_compound_binding about whether
    offsets are relative to the start of the region or to the start of the
    cluster was leading to incorrect handling of default values, leading
    to false positives from -Wanalyzer-use-of-uninitialized-value, from
    -Wanalyzer-exposure-through-uninit-copy, and other logic errors.

    Fixed thusly.

    gcc/analyzer/ChangeLog:
            PR analyzer/112969
            * store.cc (binding_cluster::maybe_get_compound_binding): When
            populating default_map, express the bit-range of the default key
            for REG relative to REG, rather than to the base region.

    gcc/testsuite/ChangeLog:
            PR analyzer/112969
            * c-c++-common/analyzer/compound-assignment-5.c (test_3): Remove
            xfails, reorder tests.
            * c-c++-common/analyzer/compound-assignment-pr112969.c: New test.
            * gcc.dg/plugin/infoleak-pr112969.c: New test.
            * gcc.dg/plugin/plugin.exp: Add infoleak-pr112969.c to
            analyzer_kernel_plugin.c tests.

    Signed-off-by: David Malcolm <dmalcolm@redhat.com>