On Wed, Feb 18, 2015 at 01:54:17PM -0800, H.J. Lu wrote: > On Wed, Feb 18, 2015 at 1:40 PM, Mark Wielaard <m...@redhat.com> wrote: > > On Wed, 2015-02-18 at 12:53 -0800, H.J. Lu wrote: > >> On Wed, Feb 18, 2015 at 12:32 PM, Mark Wielaard <m...@redhat.com> wrote: > >> > That doesn't seem like a smart default. And why is is Linux/x86 only? > >> > Shouldn't that be something that is done explicitly by a distro > >> > configuring binutils after making sure it actually is beneficial > >> > (debuginfo is often compressed in a different way, on the package/file > >> > level or with dwz). And after making sure all tools actually work with > >> > it? There are various tools that don't handle the .zdebug format like > >> > valgrind. And at least elfutils has trouble with it for ET_REL files, > >> > like kernel modules, because relocations don't actually apply anymore to > >> > the section data as is (but only after the decompression). > >> > >> Now it becomes a monthly topic: > >> > >> https://sourceware.org/ml/binutils/2015-01/msg00089.html > > > > Thanks, I hadn't seen that before. Alan Modra makes some good points in > > that thread why it is not a good change: > > https://sourceware.org/ml/binutils/2015-01/msg00135.html > > Do people agree with that? And/Or can the change be reverted for now > > till there is agreement it is a desirable default? > > > > It may not be a good idea for all targets. If you find an issue > on Linux/x86, please file a bug binutils report.
The issue is that this is not something that is target architecture specific. As others have pointed out this isn't something that is target architecture-dependent. So please first get agreement on whether or not to default for the OS (or for all ELF targets or the GNU targets). Otherwise distros will have to revert on a target by target basis to get something consistent. Secondly the bug is not directly in binutils (but there might be an issue between versions compiled with/without zlib support). If .zdebug sections are left in on disk ET_REL files, like kernel modules, there is a problem for programs that don't deal with .zdebug sections (and/or relocations against them) in ET_REL files like elfutils, systemtap, debugedit, dwz, etc. Thanks, Mark
