* [Bug default/24345] New: Dwz invalidates debug sections generated by --emit-relocs
@ 2019-01-01 0:00 vries at gcc dot gnu.org
2019-01-01 0:00 ` [Bug default/24345] " vries at gcc dot gnu.org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: vries at gcc dot gnu.org @ 2019-01-01 0:00 UTC (permalink / raw)
To: dwz
https://sourceware.org/bugzilla/show_bug.cgi?id=24345
Bug ID: 24345
Summary: Dwz invalidates debug sections generated by
--emit-relocs
Product: dwz
Version: unspecified
Status: NEW
Severity: normal
Priority: P2
Component: default
Assignee: nobody at sourceware dot org
Reporter: vries at gcc dot gnu.org
CC: dwz at sourceware dot org
Target Milestone: ---
When compiling hello world, we can keep the relocations in the executable using
linker option --emit-relocs:
...
$ gcc hello.c -g -Wl,--emit-relocs
...
So we have:
...
[35] .debug_info PROGBITS 0000000000000000 000011a0
00000000000005bb 0000000000000000 0 0 1
[36] .rela.debug_info RELA 0000000000000000 00003138
0000000000000c78 0000000000000018 I 44 35 8
...
Using readelf, we find f.i. this string relocation:
...
$ readelf -r -w a.out
Relocation section '.rela.debug_info' at offset 0x3138 contains 133 entries:
Offset Info Type Sym. Value Sym. Name +
Addend
000000000024 00200000000a R_X86_64_32 0000000000000000 .debug_str + 1a
...
for this location:
...
<24> DW_AT_comp_dir : (indirect string, offset: 0x1a):
/home/abuild/rpmbuild/BUILD/glibc-2.26/csu
...
However, if we run dwz, then .debug_info is modified:
...
<24> DW_AT_encoding : 5 (signed)
...
but .rela.debug_info is not.
So, dwz breaks the validity of .rela.debug_info.
--
You are receiving this mail because:
You are on the CC list for the bug.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug default/24345] Dwz invalidates debug sections generated by --emit-relocs
2019-01-01 0:00 [Bug default/24345] New: Dwz invalidates debug sections generated by --emit-relocs vries at gcc dot gnu.org
@ 2019-01-01 0:00 ` vries at gcc dot gnu.org
2019-01-01 0:00 ` vries at gcc dot gnu.org
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: vries at gcc dot gnu.org @ 2019-01-01 0:00 UTC (permalink / raw)
To: dwz
https://sourceware.org/bugzilla/show_bug.cgi?id=24345
Tom de Vries <vries at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at redhat dot com
--- Comment #1 from Tom de Vries <vries at gcc dot gnu.org> ---
I'm not sure how this should be addressed.
Refusing to optimize when finding debug .rela sections would fix this, but it
would also hurt linux kernel debug info compression, so that's probably not a
good idea.
I suppose ideally, we'd update the .rela sections (see also PR24344).
For now, we could drop the .rela sections, since they're broken.
At the very least, we have to emit a warning letting the user know that debug
.rela sections are broken.
--
You are receiving this mail because:
You are on the CC list for the bug.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug default/24345] Dwz invalidates debug sections generated by --emit-relocs
2019-01-01 0:00 [Bug default/24345] New: Dwz invalidates debug sections generated by --emit-relocs vries at gcc dot gnu.org
2019-01-01 0:00 ` [Bug default/24345] " vries at gcc dot gnu.org
@ 2019-01-01 0:00 ` vries at gcc dot gnu.org
2020-09-13 14:50 ` mark at klomp dot org
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: vries at gcc dot gnu.org @ 2019-01-01 0:00 UTC (permalink / raw)
To: dwz
https://sourceware.org/bugzilla/show_bug.cgi?id=24345
Tom de Vries <vries at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Severity|normal |enhancement
--
You are receiving this mail because:
You are on the CC list for the bug.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug default/24345] Dwz invalidates debug sections generated by --emit-relocs
2019-01-01 0:00 [Bug default/24345] New: Dwz invalidates debug sections generated by --emit-relocs vries at gcc dot gnu.org
2019-01-01 0:00 ` [Bug default/24345] " vries at gcc dot gnu.org
2019-01-01 0:00 ` vries at gcc dot gnu.org
@ 2020-09-13 14:50 ` mark at klomp dot org
2021-02-12 14:31 ` mark at klomp dot org
2021-02-12 14:35 ` mark at klomp dot org
4 siblings, 0 replies; 6+ messages in thread
From: mark at klomp dot org @ 2020-09-13 14:50 UTC (permalink / raw)
To: dwz
https://sourceware.org/bugzilla/show_bug.cgi?id=24345
Mark Wielaard <mark at klomp dot org> changed:
What |Removed |Added
----------------------------------------------------------------------------
See Also| |https://sourceware.org/bugz
| |illa/show_bug.cgi?id=24344
--
You are receiving this mail because:
You are on the CC list for the bug.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug default/24345] Dwz invalidates debug sections generated by --emit-relocs
2019-01-01 0:00 [Bug default/24345] New: Dwz invalidates debug sections generated by --emit-relocs vries at gcc dot gnu.org
` (2 preceding siblings ...)
2020-09-13 14:50 ` mark at klomp dot org
@ 2021-02-12 14:31 ` mark at klomp dot org
2021-02-12 14:35 ` mark at klomp dot org
4 siblings, 0 replies; 6+ messages in thread
From: mark at klomp dot org @ 2021-02-12 14:31 UTC (permalink / raw)
To: dwz
https://sourceware.org/bugzilla/show_bug.cgi?id=24345
Mark Wielaard <mark at klomp dot org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |vt at altlinux dot org
--- Comment #2 from Mark Wielaard <mark at klomp dot org> ---
*** Bug 27029 has been marked as a duplicate of this bug. ***
--
You are receiving this mail because:
You are on the CC list for the bug.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug default/24345] Dwz invalidates debug sections generated by --emit-relocs
2019-01-01 0:00 [Bug default/24345] New: Dwz invalidates debug sections generated by --emit-relocs vries at gcc dot gnu.org
` (3 preceding siblings ...)
2021-02-12 14:31 ` mark at klomp dot org
@ 2021-02-12 14:35 ` mark at klomp dot org
4 siblings, 0 replies; 6+ messages in thread
From: mark at klomp dot org @ 2021-02-12 14:35 UTC (permalink / raw)
To: dwz
https://sourceware.org/bugzilla/show_bug.cgi?id=24345
Mark Wielaard <mark at klomp dot org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |mark at klomp dot org
--- Comment #3 from Mark Wielaard <mark at klomp dot org> ---
See also this gcc discussion about --emit-relocs:
https://gcc.gnu.org/pipermail/gcc/2020-December/234405.html
And this elfutils one:
https://sourceware.org/pipermail/elfutils-devel/2020q4/003237.html
--
You are receiving this mail because:
You are on the CC list for the bug.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-02-12 14:35 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-01-01 0:00 [Bug default/24345] New: Dwz invalidates debug sections generated by --emit-relocs vries at gcc dot gnu.org
2019-01-01 0:00 ` [Bug default/24345] " vries at gcc dot gnu.org
2019-01-01 0:00 ` vries at gcc dot gnu.org
2020-09-13 14:50 ` mark at klomp dot org
2021-02-12 14:31 ` mark at klomp dot org
2021-02-12 14:35 ` mark at klomp dot org
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).