From patchwork Fri Feb 10 13:01:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Wielaard X-Patchwork-Id: 64667 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 62DCF385B510 for ; Fri, 10 Feb 2023 13:01:34 +0000 (GMT) X-Original-To: elfutils-devel@sourceware.org Delivered-To: elfutils-devel@sourceware.org Received: from gnu.wildebeest.org (gnu.wildebeest.org [45.83.234.184]) by sourceware.org (Postfix) with ESMTPS id 3754B3858D28 for ; Fri, 10 Feb 2023 13:01:27 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 3754B3858D28 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=klomp.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=klomp.org Received: from r6.localdomain (82-217-174-174.cable.dynamic.v4.ziggo.nl [82.217.174.174]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by gnu.wildebeest.org (Postfix) with ESMTPSA id AF2E230067D8; Fri, 10 Feb 2023 14:01:24 +0100 (CET) Received: by r6.localdomain (Postfix, from userid 1000) id 8DC4F3401CF; Fri, 10 Feb 2023 14:01:24 +0100 (CET) From: Mark Wielaard To: elfutils-devel@sourceware.org Cc: Mark Wielaard Subject: [PATCH] libdw: Handle DW_OP_GNU_uninit in dwarf_getlocation Date: Fri, 10 Feb 2023 14:01:12 +0100 Message-Id: <20230210130112.1093665-1-mark@klomp.org> X-Mailer: git-send-email 2.39.1 MIME-Version: 1.0 X-Spam-Status: No, score=-3036.2 required=5.0 tests=BAYES_00, GIT_PATCH_0, JMQ_SPF_NEUTRAL, KAM_DMARC_STATUS, RCVD_IN_BARRACUDACENTRAL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: elfutils-devel@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Elfutils-devel mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , Errors-To: elfutils-devel-bounces+patchwork=sourceware.org@sourceware.org Sender: "Elfutils-devel" dwarf_getlocation would return an error when it saw a DW_OP_GNU_uninit. Handle it by simply recognizing as a no argument operation. DW_OP_GNU_uninit is emitted by GCC as a marker to flag the location expression as referring to an uninitialized value. Signed-off-by: Mark Wielaard --- libdw/ChangeLog | 5 +++++ libdw/dwarf_getlocation.c | 1 + tests/ChangeLog | 4 ++++ tests/varlocs.c | 6 ++++++ 4 files changed, 16 insertions(+) diff --git a/libdw/ChangeLog b/libdw/ChangeLog index 71e96c88..9bea831e 100644 --- a/libdw/ChangeLog +++ b/libdw/ChangeLog @@ -1,3 +1,8 @@ +2023-02-10 Mark Wielaard + + * dwarf_getlocation.c (__libdw_intern_expression): Handle + DW_OP_GNU_uninit. + 2023-01-22 Mark Wielaard * dwarf_getscopes.c (pc_record): Return nscopes when done. diff --git a/libdw/dwarf_getlocation.c b/libdw/dwarf_getlocation.c index d0d78163..553fdc98 100644 --- a/libdw/dwarf_getlocation.c +++ b/libdw/dwarf_getlocation.c @@ -396,6 +396,7 @@ __libdw_intern_expression (Dwarf *dbg, bool other_byte_order, case DW_OP_form_tls_address: case DW_OP_GNU_push_tls_address: case DW_OP_stack_value: + case DW_OP_GNU_uninit: /* No operand. */ break; diff --git a/tests/ChangeLog b/tests/ChangeLog index 974a3a4f..fd261bc6 100644 --- a/tests/ChangeLog +++ b/tests/ChangeLog @@ -1,3 +1,7 @@ +2023-02-10 Mark Wielaard + + * varlocs.c (print_expr): Handle DW_OP_GNU_uninit. + 2023-02-03 Mark Wielaard * run-addr2line-C-test.sh: Check ELFUTILS_DISABLE_DEMANGLE. diff --git a/tests/varlocs.c b/tests/varlocs.c index d2c13767..8e563fd3 100644 --- a/tests/varlocs.c +++ b/tests/varlocs.c @@ -251,6 +251,12 @@ print_expr (Dwarf_Attribute *attr, Dwarf_Op *expr, Dwarf_Addr addr, int depth) printf ("%s", opname); break; + case DW_OP_GNU_uninit: + /* No arguments. Special. It means the expression describes + an value which hasn't been initialized (yet). */ + printf ("%s", opname); + break; + case DW_OP_call_frame_cfa: /* No arguments. Special. Pushes Call Frame Address as computed by CFI data (dwarf_cfi_addrframe will fetch that info (either from