Red Hat Bugzilla – Bug 526533
Rebase of GDB to 7.0, the F12 version
Last modified: 2010-08-19 04:14:34 EDT
Description of problem:
Rebase to the F12 GDB (GDB-7.0) has been considered as the most feasible way to resolve Bug 467502 and Bug 520618 both showing larger problems with threads.
Version-Release number of selected component (if applicable):
Bug 467502 did show some problems in the threads support of FSF GDB 6.8 (which is the base for the current RHEL-5.4 GDB).
While re-evaluating this bugfix Bug 467502 for a new performance Bug 520618 found out various threads regressions. Their fix would require too many patches to backport moreover having issues with the RH PIE (Position-Independent-Executable) patch.
F12 contains already the full fix set tested both in Fedora and by FSF GDB 7.0, the PIE patch compatibility is at least tested by Fedora (+SuSE).
A pre-6.8 regression in Bug 467502 was introduced by:
[8/9] multiple locations
One of the later fixes was:
Re: [RFA] Try2: Ignore breakpoints when reading memory.
A different also required fix was:
Fixes for a couple of infrun bugs (thread hop, revert to step thread).
These patches introduce general restoration from breakpoint shadows which is not required for RHEL-5 but other patches heavily depend on it, incl. my performance fixing patch:
This would mean either
(a) Introduce new untested fixes of the 6.8 threading bugs not based on the
breakpoints shadow restoration patches.
(b) Properly cherry-pick all the breakpoints shadow restoration patches fixing
the threading bugs, incl. rebasement of the RH PIE patch.
Neither of two paths provide small enough change not being tested in the field to be acceptable for RHEL-5.
F12 is now gdb-220.127.116.1190925-2.fc12 which is already from FSF GDB 7.0 branch (gdb_7_0-branch). Formal gdb-7.0 Fedora update should be made soon after the FSF GDB release.
The rebase from Fedora will need some minor .spec adjustments for RHEL as before.
F12 Fedora will need minor fixups for RHEL-5 arches not on Fedora (ia64, s390x).
The rebase will include a full RHEL-5 arches regression test as usual.
Fixed in gdb-7.0-13.el5.
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.