https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104369
--- Comment #1 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by David Malcolm <dmalc...@gcc.gnu.org>: https://gcc.gnu.org/g:3ef328c293a336df0aead2d72c0c5ed9781a9861 commit r12-7040-g3ef328c293a336df0aead2d72c0c5ed9781a9861 Author: David Malcolm <dmalc...@redhat.com> Date: Wed Feb 2 16:39:12 2022 -0500 analyzer: fixes to realloc-handling [PR104369] This patch fixes various issues with how -fanalyzer handles "realloc" seen when debugging PR analyzer/104369. Previously it wasn't correctly copying over the contents of the old buffer for the success-with-move case, leading to false -Wanalyzer-use-of-uninitialized-value diagnostics. I also noticed that -fanalyzer failed to properly handle "realloc" for cases where the ptr's region had unknown dynamic extents, and an ICE for the case where a tainted value is used as a realloc size argument. This patch fixes these issues, including the false uninit diagnostics seen in PR analyzer/104369. gcc/analyzer/ChangeLog: PR analyzer/104369 * engine.cc (exploded_graph::process_node): Use the node for any diagnostics, avoiding ICE if a bifurcation update adds a saved_diagnostic, such as for a tainted realloc size. * region-model-impl-calls.cc (region_model::impl_call_realloc::success_no_move::update_model): Require the old pointer to be non-NULL to be able successfully grow in place. Use model->deref_rvalue rather than maybe_get_region to support the old pointer being symbolic. (region_model::impl_call_realloc::success_with_move::update_model): Likewise. Add a constraint that the new pointer != the old pointer. Use a sized_region when setting the value of the new region. Handle the case where we don't know the dynamic size of the old region by marking the new region as unknown. * sm-taint.cc (tainted_allocation_size::tainted_allocation_size): Update assertion to also allow for MEMSPACE_UNKNOWN. (tainted_allocation_size::emit): Likewise. (region_model::check_dynamic_size_for_taint): Likewise. gcc/testsuite/ChangeLog: PR analyzer/104369 * gcc.dg/analyzer/pr104369-1.c: New test. * gcc.dg/analyzer/pr104369-2.c: New test. * gcc.dg/analyzer/realloc-3.c: New test. * gcc.dg/analyzer/realloc-4.c: New test. * gcc.dg/analyzer/taint-realloc.c: New test. Signed-off-by: David Malcolm <dmalc...@redhat.com>
