From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id bV72Ikcf8195GwAAWB0awg (envelope-from ) for ; Mon, 04 Jan 2021 08:59:35 -0500 Received: by simark.ca (Postfix, from userid 112) id 814911F0AA; Mon, 4 Jan 2021 08:59:35 -0500 (EST) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=0.3 required=5.0 tests=MAILING_LIST_MULTI,RDNS_NONE, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.2 Received: from sourceware.org (unknown [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id C45591E99A for ; Mon, 4 Jan 2021 08:59:34 -0500 (EST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 31802383F858; Mon, 4 Jan 2021 13:59:34 +0000 (GMT) Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by sourceware.org (Postfix) with ESMTPS id 58EE9383F858 for ; Mon, 4 Jan 2021 13:59:31 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 58EE9383F858 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=tdevries@suse.de X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 786CAACAF for ; Mon, 4 Jan 2021 13:59:30 +0000 (UTC) Date: Mon, 4 Jan 2021 14:59:28 +0100 From: Tom de Vries To: gdb-patches@sourceware.org Subject: [PATCH][gdb/symtab] Remove superfluous end-of-sequence marker Message-ID: <20210104135927.GA3115@delia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: gdb-patches-bounces@sourceware.org Sender: "Gdb-patches" Hi, While working on PR26935 I noticed that when running test-case gdb.base/morestack.exp with target board unix/-m32/-fPIE/-pie and ld linker, I get this linetable fragment for morestack.S using readelf -wL: ... CU: ../../../../libgcc/config/i386/morestack.S: Line number Starting address View Stmt 109 0xc9c x ... 838 0xe03 x - 0xe04 636 0 x 637 0x3 x - 0x4 ... but with "maint info line-table" I get: ... INDEX LINE ADDRESS IS-STMT 0 END 0x00000004 Y 1 109 0x00000c9c Y ... 110 838 0x00000e03 Y 111 END 0x00000e04 Y ... So, apparently the entries with addresses 0x0 and 0x3 are filtered out because the addresses are out of range, but the same doesn't happen with the end-of-seq terminator. Fix this by filtering out end-of-seq terminators that do not actually terminate anything. Tested on x86_64-linux. Any comments? Thanks, - Tom [gdb/symtab] Remove superfluous end-of-sequence marker gdb/ChangeLog: 2021-01-04 Tom de Vries * buildsym.c (buildsym_compunit::record_line): Filter out end-of-seq terminators that do not terminate anything. gdb/testsuite/ChangeLog: 2021-01-04 Tom de Vries * gdb.dwarf2/dw2-out-of-range-end-of-seq.exp: New file. --- gdb/buildsym.c | 8 ++ .../gdb.dwarf2/dw2-out-of-range-end-of-seq.exp | 94 ++++++++++++++++++++++ 2 files changed, 102 insertions(+) diff --git a/gdb/buildsym.c b/gdb/buildsym.c index 1d8c579b7b8..245aecf0c38 100644 --- a/gdb/buildsym.c +++ b/gdb/buildsym.c @@ -714,6 +714,14 @@ buildsym_compunit::record_line (struct subfile *subfile, int line, break; subfile->line_vector->nitems--; } + + /* Ignore an end-of-sequence marker marking an empty sequence. */ + struct linetable_entry *last + = (subfile->line_vector->nitems == 0 + ? nullptr + : &subfile->line_vector->item[subfile->line_vector->nitems - 1]); + if (last == nullptr || last->line == 0) + return; } e = subfile->line_vector->item + subfile->line_vector->nitems++; diff --git a/gdb/testsuite/gdb.dwarf2/dw2-out-of-range-end-of-seq.exp b/gdb/testsuite/gdb.dwarf2/dw2-out-of-range-end-of-seq.exp new file mode 100644 index 00000000000..7a32a01389c --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-out-of-range-end-of-seq.exp @@ -0,0 +1,94 @@ +# Copyright 2021 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +# Check that an out-of-range DW_LNE_end_sequence is removed from the +# line table. + +load_lib dwarf.exp + +# This test can only be run on targets which support DWARF-2 and use gas. +if {![dwarf2_support]} { + verbose "Skipping $gdb_test_file_name." + return 0 +} + +# The .c files use __attribute__. +if [get_compiler_info] { + return -1 +} +if !$gcc_compiled { + verbose "Skipping $gdb_test_file_name." + return 0 +} + +standard_testfile main.c -dw.S + +set asm_file [standard_output_file $srcfile2] +Dwarf::assemble $asm_file { + declare_labels Llines + global srcdir subdir srcfile + + cu {} { + compile_unit { + {language @DW_LANG_C} + {name $srcfile} + {stmt_list $Llines DW_FORM_sec_offset} + } { + subprogram { + {external 1 flag} + {MACRO_AT_func {main}} + } + } + } + + lines {version 2} Llines { + include_dir "${srcdir}/${subdir}" + file_name "$srcfile" 1 + + program { + {DW_LNE_set_address main_label} + {line 1} + {DW_LNS_copy} + + {DW_LNS_advance_pc 1} + {DW_LNE_end_sequence} + + {DW_LNE_set_address 0} + {line 2} + {DW_LNS_copy} + + {DW_LNS_advance_pc 1} + {DW_LNE_end_sequence} + } + } +} + +if { [prepare_for_testing "failed to prepare" ${testfile} \ + [list $srcfile $asm_file] {nodebug}] } { + return -1 +} + +if ![runto_main] { + return -1 +} + +gdb_test_multiple "maint info line-table" "END with address 1 eliminated" { + -re -wrap "END *0x0*1 Y \r\n.*" { + fail $gdb_test_name + } + -re -wrap "" { + pass $gdb_test_name + } +}