From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Received: (qmail 7298 invoked from network); 9 Jan 2003 14:35:26 -0000 Received: from unknown (HELO hub.ott.qnx.com) (209.226.137.76) by 209.249.29.67 with SMTP; 9 Jan 2003 14:35:26 -0000 Received: from smtp.ott.qnx.com (smtp.ott.qnx.com [10.0.2.158]) by hub.ott.qnx.com (8.9.3/8.9.3) with ESMTP id JAA31205; Thu, 9 Jan 2003 09:27:09 -0500 Received: from node109 (node109 [10.0.0.109]) by smtp.ott.qnx.com (8.8.8/8.6.12) with ESMTP id JAA25496; Thu, 9 Jan 2003 09:35:13 -0500 Date: Thu, 09 Jan 2003 14:35:00 -0000 From: Colin Burgess X-Sender: cburgess@node109.ott.qnx.com To: Kevin Buettner cc: Kris Warkentin , Paul Koning , gdb@sources.redhat.com, Peter van der Veen Subject: Re: relocation of shared libs not based at 0 In-Reply-To: <1030108222435.ZM25608@localhost.localdomain> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SW-Source: 2003-01/txt/msg00127.txt.bz2 You already have architecture dependant code in fetch_link_map_offsets, couldn't you do something similar for relocate_section_addresses? On Wed, 8 Jan 2003, Kevin Buettner wrote: > On Jan 8, 4:52pm, Kris Warkentin wrote: > > > This works fine on QNX and (I assume) NetBSD so it looks rather like we just > > have a difference of opinion on how the shared object loader should fill > > things in. We wanted to keep our linker's behaviour for some future > > enhancements (pre-relocating shared objects on flash memory, etc.) so I was > > hoping the fix below (Paul's code with some extra comments) might be > > acceptable. That way Paul and I could just define LM_ADDR_IS_NOT_LOAD_BASE > > in our tm-.h and we'd be off to the races. > > > > static void > > svr4_relocate_section_addresses (struct so_list *so, > > struct section_table *sec) > > { > > #if LM_ADDR_IS_NOT_LOAD_BASE > > /* On some platforms, (ie. QNX, NetBSD) LM_ADDR is the assigned > > address, not the offset. > > The addresses are formed as follows: > > LM_ADDR is the target address where the shared library file > > is mapped, so the actual section start address is LM_ADDR plus > > the section offset within the shared library file. The end > > address is that plus the section length. Note that we pay no > > attention to the section start address as recorded in the > > library header. > > */ > > sec->endaddr = svr4_truncate_ptr (sec->endaddr - sec->addr + > > sec->the_bfd_section->filepos + > > LM_ADDR (so)); > > sec->addr = svr4_truncate_ptr (sec->the_bfd_section->filepos + > > LM_ADDR (so)); > > #else > > sec->addr = svr4_truncate_ptr (sec->addr + LM_ADDR (so)); > > sec->endaddr = svr4_truncate_ptr (sec->endaddr + LM_ADDR (so)); > > #endif > > } > > The problem that I have with the above is that it's not possible to > build a cross debugger that'll have shared library support for both > Linux and NetBSD. > > If we could somehow detect (perhaps via the osabi mechanism) that we > have one of the lm-addr-is-not-load-base platforms and enable that > code at runtime, I wouldn't mind... > > Kevin > -- cburgess@qnx.com