https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63272
--- Comment #8 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:9d6a0f388eb048f8d87f47af78f07b5ce513bfe6 commit r12-6606-g9d6a0f388eb048f8d87f47af78f07b5ce513bfe6 Author: Martin Sebor <mse...@redhat.com> Date: Sat Jan 15 16:41:40 2022 -0700 Add -Wdangling-pointer [PR63272]. Resolves: PR c/63272 - GCC should warn when using pointer to dead scoped variable with in the same function gcc/c-family/ChangeLog: PR c/63272 * c.opt (-Wdangling-pointer): New option. gcc/ChangeLog: PR c/63272 * diagnostic-spec.c (nowarn_spec_t::nowarn_spec_t): Handle -Wdangling-pointer. * doc/invoke.texi (-Wdangling-pointer): Document new option. * gimple-ssa-warn-access.cc (pass_waccess::clone): Set new member. (pass_waccess::check_pointer_uses): New function. (pass_waccess::gimple_call_return_arg): New function. (pass_waccess::gimple_call_return_arg_ref): New function. (pass_waccess::check_call_dangling): New function. (pass_waccess::check_dangling_uses): New function overloads. (pass_waccess::check_dangling_stores): New function. (pass_waccess::check_dangling_stores): New function. (pass_waccess::m_clobbers): New data member. (pass_waccess::m_func): New data member. (pass_waccess::m_run_number): New data member. (pass_waccess::m_check_dangling_p): New data member. (pass_waccess::check_alloca): Check m_early_checks_p. (pass_waccess::check_alloc_size_call): Same. (pass_waccess::check_strcat): Same. (pass_waccess::check_strncat): Same. (pass_waccess::check_stxcpy): Same. (pass_waccess::check_stxncpy): Same. (pass_waccess::check_strncmp): Same. (pass_waccess::check_memop_access): Same. (pass_waccess::check_read_access): Same. (pass_waccess::check_builtin): Call check_pointer_uses. (pass_waccess::warn_invalid_pointer): Add arguments. (is_auto_decl): New function. (pass_waccess::check_stmt): New function. (pass_waccess::check_block): Call check_stmt. (pass_waccess::execute): Call check_dangling_uses, check_dangling_stores. Empty m_clobbers. * passes.def (pass_warn_access): Invoke pass two more times. gcc/testsuite/ChangeLog: PR c/63272 * g++.dg/warn/Wfree-nonheap-object-6.C: Disable valid warnings. * g++.dg/warn/ref-temp1.C: Prune expected warning. * gcc.dg/uninit-pr50476.c: Expect a new warning. * c-c++-common/Wdangling-pointer-2.c: New test. * c-c++-common/Wdangling-pointer-3.c: New test. * c-c++-common/Wdangling-pointer-4.c: New test. * c-c++-common/Wdangling-pointer-5.c: New test. * c-c++-common/Wdangling-pointer-6.c: New test. * c-c++-common/Wdangling-pointer.c: New test. * g++.dg/warn/Wdangling-pointer-2.C: New test. * g++.dg/warn/Wdangling-pointer.C: New test. * gcc.dg/Wdangling-pointer-2.c: New test. * gcc.dg/Wdangling-pointer.c: New test.