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* [Bug debug/54568] New: Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets
@ 2012-09-13 14:32 hjl.tools at gmail dot com
2012-09-13 15:50 ` [Bug debug/54568] " hjl.tools at gmail dot com
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: hjl.tools at gmail dot com @ 2012-09-13 14:32 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54568
Bug #: 54568
Summary: Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME
targets
Classification: Unclassified
Product: gcc
Version: 4.8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: debug
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: hjl.tools@gmail.com
From
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24724#c15
--
On a system whose linker supports --eh-frame-hdr, we will use the version of
_Unwind_Find_FDE in unwind-dw2-fde-dip.c. It will override the version in
unwind-dw2-fde.c by renaming it via #define. This file is selected by
libgcc/config/t-eh-dw2-dip. It will still call the version of
_Unwind_Find_FDE, but that function will only look through files registered by
__register_frame_info_bases. __register_frame_info_bases is called by
crtstuff.c, but it is only called on systems whose linker does not support
--eh-frame-hdr.
--
On PT_GNU_EH_FRAME targets, even __register_frame_info_bases isn't
defined/used, we still include unwind-dw2-fde.c and call its
_Unwind_Find_FDE as _Unwind_Find_registered_FDE. Should we skip
the whole thing?
^ permalink raw reply [flat|nested] 5+ messages in thread* [Bug debug/54568] Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets 2012-09-13 14:32 [Bug debug/54568] New: Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets hjl.tools at gmail dot com @ 2012-09-13 15:50 ` hjl.tools at gmail dot com 2012-09-13 16:11 ` jakub at gcc dot gnu.org ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: hjl.tools at gmail dot com @ 2012-09-13 15:50 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54568 H.J. Lu <hjl.tools at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jakub at redhat dot com --- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> 2012-09-13 15:50:08 UTC --- It is needed by crtbeginT.o for -static since PT_GNU_EH_FRAME isn't used for static executables. However, dl_iterate_phdr works fine with libc.a from glibc. Jakub, do you remember why PT_GNU_EH_FRAME isn't used on static executables? ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug debug/54568] Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets 2012-09-13 14:32 [Bug debug/54568] New: Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets hjl.tools at gmail dot com 2012-09-13 15:50 ` [Bug debug/54568] " hjl.tools at gmail dot com @ 2012-09-13 16:11 ` jakub at gcc dot gnu.org 2012-09-13 16:18 ` hjl.tools at gmail dot com 2012-09-13 22:23 ` [Bug debug/54568] --eh-frame-hdr should also be enabled for static executable hjl.tools at gmail dot com 3 siblings, 0 replies; 5+ messages in thread From: jakub at gcc dot gnu.org @ 2012-09-13 16:11 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54568 Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jakub at gcc dot gnu.org --- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-09-13 16:11:12 UTC --- Think about libraries built with older GCC versions or built with older binutils. Those would still call the register routines instead of building .eh_frame_hdr. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug debug/54568] Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets 2012-09-13 14:32 [Bug debug/54568] New: Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets hjl.tools at gmail dot com 2012-09-13 15:50 ` [Bug debug/54568] " hjl.tools at gmail dot com 2012-09-13 16:11 ` jakub at gcc dot gnu.org @ 2012-09-13 16:18 ` hjl.tools at gmail dot com 2012-09-13 22:23 ` [Bug debug/54568] --eh-frame-hdr should also be enabled for static executable hjl.tools at gmail dot com 3 siblings, 0 replies; 5+ messages in thread From: hjl.tools at gmail dot com @ 2012-09-13 16:18 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54568 --- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> 2012-09-13 16:18:24 UTC --- (In reply to comment #2) > Think about libraries built with older GCC versions or built with older > binutils. Those would still call the register routines instead of building > .eh_frame_hdr. We are talking static executables here. .eh-frame-hdr section is generated by the linker to create static executable and we know --eh-frame-hdr works with the linker. Why shouldn't --eh-frame-hdr work for static executable linked with libraries built with older GCC versions or built with older binutils? ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug debug/54568] --eh-frame-hdr should also be enabled for static executable 2012-09-13 14:32 [Bug debug/54568] New: Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets hjl.tools at gmail dot com ` (2 preceding siblings ...) 2012-09-13 16:18 ` hjl.tools at gmail dot com @ 2012-09-13 22:23 ` hjl.tools at gmail dot com 3 siblings, 0 replies; 5+ messages in thread From: hjl.tools at gmail dot com @ 2012-09-13 22:23 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54568 H.J. Lu <hjl.tools at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Summary|Unused codes in |--eh-frame-hdr should also |unwind-dw2-fde.c on |be enabled for static |PT_GNU_EH_FRAME targets |executable --- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> 2012-09-13 22:23:08 UTC --- The old interface is needed for DSO and executable created by the older binutils. However, it has nothing to with -static. Also for Android targets, there is no old DSO. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2012-09-13 22:23 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2012-09-13 14:32 [Bug debug/54568] New: Unused codes in unwind-dw2-fde.c on PT_GNU_EH_FRAME targets hjl.tools at gmail dot com 2012-09-13 15:50 ` [Bug debug/54568] " hjl.tools at gmail dot com 2012-09-13 16:11 ` jakub at gcc dot gnu.org 2012-09-13 16:18 ` hjl.tools at gmail dot com 2012-09-13 22:23 ` [Bug debug/54568] --eh-frame-hdr should also be enabled for static executable hjl.tools at gmail dot com
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