From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25533 invoked by alias); 14 Feb 2003 15:26:45 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 25521 invoked from network); 14 Feb 2003 15:26:45 -0000 Received: from unknown (HELO crack.them.org) (65.125.64.184) by 172.16.49.205 with SMTP; 14 Feb 2003 15:26:45 -0000 Received: from nevyn.them.org ([66.93.61.169] ident=mail) by crack.them.org with asmtp (Exim 3.12 #1 (Debian)) id 18jjcQ-0000N1-00; Fri, 14 Feb 2003 11:27:22 -0600 Received: from drow by nevyn.them.org with local (Exim 3.36 #1 (Debian)) id 18jhjH-000065-00; Fri, 14 Feb 2003 10:26:19 -0500 Date: Fri, 14 Feb 2003 15:26:00 -0000 From: Daniel Jacobowitz To: Michal Ludvig Cc: Daniel Berlin , gdb , gcc@sources.redhat.com Subject: Re: Reference to .debug_loc Message-ID: <20030214152619.GD30416@nevyn.them.org> Mail-Followup-To: Michal Ludvig , Daniel Berlin , gdb , gcc@sources.redhat.com References: <3E4D03F3.40103@suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3E4D03F3.40103@suse.cz> User-Agent: Mutt/1.5.1i X-SW-Source: 2003-02/txt/msg00238.txt.bz2 On Fri, Feb 14, 2003 at 03:57:55PM +0100, Michal Ludvig wrote: > Hi again, > when location lists are in use, .debug_info looks like this: > > .section .debug_info > .long 0x187 # Length of Compilation Unit Info > .value 0x2 # DWARF version number > .long .Ldebug_abbrev0 # Offset Into Abbrev. Section > .byte 0x8 # Pointer Size (in bytes) > .uleb128 0x1 # (DIE (0xb) DW_TAG_compile_unit) > .long .Ldebug_line0 # DW_AT_stmt_list > .quad .Letext0 # DW_AT_high_pc > .quad .Ltext0 # DW_AT_low_pc > .byte 0x1 # DW_AT_language > [...] > .uleb128 0x3 # (DIE (0x50) DW_TAG_formal_parameter) > .long .LASF2 # DW_AT_name: "value" > .byte 0x1 # DW_AT_decl_file > .byte 0x2 # DW_AT_decl_line > .long 0x8f # DW_AT_type > .long .LLST0-.Ldebug_loc0 # DW_AT_location > > So, the reference to .debug_loc on the last line of the example > (DW_AT_location) is an offset within that section, ie. it's 0 (NULL) for > the first entry with a location list. However when I link several .o > files together, each of them have DW_AT_location entries based at the > same NULL. > > This time I realy can't see a way to find out at what position in the > resulting (ie. linked from several ones) .debug_loc should I start > reading for a given compilation unit. > > Should there be something more in the CU header? Something similar to > .long .Ldebug_abbrev0 # Offset Into Abbrev. Section > For example > .long .Ldebug_loc0 # Offset Into Loclist Section > > Or is there another way? At a guess it should be like DW_AT_ranges: .long .Ldebug_ranges0+0x0 # DW_AT_ranges I.E. dw2_asm_output_offset, rather than dw2_asm_output_delta, in GCC. -- Daniel Jacobowitz MontaVista Software Debian GNU/Linux Developer