From: "Guillermo E. Martinez" <guillermo.e.martinez@oracle.com>
To: Mark Wielaard <mark@klomp.org>
Cc: Nick Clifton <nickc@redhat.com>, elfutils-devel@sourceware.org
Subject: Re: [PATCH v3] strip: keep .ctf section in stripped file
Date: Tue, 7 Mar 2023 14:47:57 -0600 [thread overview]
Message-ID: <20230307204757.iroxwejwyvupaz2v@kamehouse> (raw)
In-Reply-To: <cf925c95a1b9cc155b2275ebe9d74a2e81c36899.camel@klomp.org>
On Tue, Mar 07, 2023 at 03:50:01PM +0100, Mark Wielaard wrote:
> Hi Nick, Hi Guillermo,
>
Hi Mark,
> On Sat, 2023-03-04 at 08:00 -0600, Guillermo E. Martinez wrote:
> > Hello,
> >
> > On Fri, Mar 03, 2023 at 12:24:19PM +0000, Nick Clifton wrote:
> > > Hi Mark,
> > >
> > > > > > I am mainly wondering why binutils strip already seems to keep ".ctf"
> > > > > > sections (even without -g).
> > >
> > > > Right. But I am wondering how that mechanism works with binutils strip.
> > > > Apparently we do something different in eu-strip which makes it
> > > > necessary to add a --keep-ctf option based on the section name. It
> > > > would be good if we figured out how/what we can do to keep the
> > > > different strip utilities in sync.
> > >
> > > I think that the function that does this is "is_strip_section_1" in
> >
> > That's right, this function decided whether the section will be striped
> > out by default, if it has set `SEC_DEBUGGING' in BFD section flags then
> > section is removed by the default. For `.ctf' this flag is not set
> > because in `_bfd_elf_make_section_from_shdr' when BFD sections are
> > building it uses the section's name: ".debug", ".gnu.debuglto_.debug_",
> > ".gnu.linkonce.wi.", ".zdebug", "lines", ".stab", etc, to set
> > `SEC_DEBUGGING' flag.
> >
> > > binutils/objcopy.c. If an input section has the BSF_DEBUGGING flag
> > > set (an internal flag to he BFD library, but basically it should be
> > > set for all debug sections, including .ctf sections I think), then
> > > the basic decision is to keep the section unless -g is used.
>
> OK, that is interesting. So given the .ctf section is NOT marked as
> SEC_DEBUGGING binutils strip basically never strips it.
>
> While eu-strip does strip it by default (since it is a non-loadable
> PROGBITS section), but keeps it with -g (which only strips the
> explicitly named .debug sections).
>
> But both binutils strip and eu-strip do have --keep-section=.ctf which
> would explicitly keep it even without -g, and both have --remove-
> section=.ctf which always removes the section.
>
> So binutils strip and eu-strip aren't totally identical with the
> default flags, but with --keep-section=.ctf and --remove-section=.ctf
> they seem to do the same thing.
>
> So I am not sure we really need a --keep-ctf flag for eu-strip (unless
> we also get it for binutils strip). My preference would be to just
> recommend a user use --keep-section=.ctf or --remove-section=.ctf to
> indicate what they want.
>
Oh, I see. My first motivation to add `--keep-ctf' in `eu-strip' is
because it's used by `find-debuginfo.sh' script to build the debug RPM
packages:
`eu-strip --remove-comment $r $g ${keep_remove_args} -f "$1" "$2" || exit'
So, `eu-strip' removes `.ctf' section by default.
In this case I'll prepare a patch updating `find-debuginfo.sh' to add
`--keep-section=.ctf' to `eu-strip' to preserve such section.
Thanks for your comments!
guillermo
next prev parent reply other threads:[~2023-03-07 20:48 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-31 2:26 [PATCH] " Guillermo E. Martinez
2022-05-31 7:06 ` Mark Wielaard
2022-05-31 10:26 ` Jose E. Marchesi
2022-05-31 12:50 ` Jose E. Marchesi
2022-06-01 4:34 ` Guillermo E. Martinez
2022-06-01 15:55 ` [PATCHv2] " Guillermo E. Martinez
2022-12-20 21:35 ` Mark Wielaard
2023-02-22 16:42 ` Mark Wielaard
2023-02-22 16:59 ` Jose E. Marchesi
2023-02-22 17:12 ` Guillermo E. Martinez
2023-02-22 23:04 ` Mark Wielaard
2023-02-23 18:34 ` Guillermo E. Martinez
2023-02-23 18:42 ` [PATCH v3] " Guillermo E. Martinez
2023-02-24 11:51 ` Mark Wielaard
2023-02-24 16:48 ` Guillermo E. Martinez
2023-02-28 12:24 ` Mark Wielaard
2023-02-28 12:45 ` Nick Clifton
2023-02-28 12:59 ` Nick Clifton
2023-02-28 14:27 ` Mark Wielaard
2023-03-03 2:40 ` Guillermo E. Martinez
2023-03-03 12:15 ` Mark Wielaard
2023-03-03 12:24 ` Nick Clifton
2023-03-04 14:00 ` Guillermo E. Martinez
2023-03-07 14:50 ` Mark Wielaard
2023-03-07 20:47 ` Guillermo E. Martinez [this message]
2023-03-08 17:45 ` Nix
2023-03-09 23:08 ` Mark Wielaard
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230307204757.iroxwejwyvupaz2v@kamehouse \
--to=guillermo.e.martinez@oracle.com \
--cc=elfutils-devel@sourceware.org \
--cc=mark@klomp.org \
--cc=nickc@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).